// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 2007+ Copyright (c) Evgeniy Polyakov <johnpol@2ka.mipt.ru>
 * All rights reserved.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/mod_devicetable.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>
#include <linux/highmem.h>
#include <linux/crypto.h>
#include <linux/hw_random.h>
#include <linux/ktime.h>

#include <crypto/algapi.h>
#include <crypto/internal/des.h>
#include <crypto/internal/skcipher.h>

static char hifn_pll_ref[sizeof("extNNN")] = "ext";
module_param_string(hifn_pll_ref, hifn_pll_ref, sizeof(hifn_pll_ref), 0444);
MODULE_PARM_DESC(hifn_pll_ref,
                 "PLL reference clock (pci[freq] or ext[freq], default ext)");

static atomic_t hifn_dev_number;

#define ACRYPTO_OP_DECRYPT      0
#define ACRYPTO_OP_ENCRYPT      1
#define ACRYPTO_OP_HMAC         2
#define ACRYPTO_OP_RNG          3

#define ACRYPTO_MODE_ECB                0
#define ACRYPTO_MODE_CBC                1
#define ACRYPTO_MODE_CFB                2
#define ACRYPTO_MODE_OFB                3

#define ACRYPTO_TYPE_AES_128    0
#define ACRYPTO_TYPE_AES_192    1
#define ACRYPTO_TYPE_AES_256    2
#define ACRYPTO_TYPE_3DES       3
#define ACRYPTO_TYPE_DES        4

#define PCI_VENDOR_ID_HIFN              0x13A3
#define PCI_DEVICE_ID_HIFN_7955         0x0020
#define PCI_DEVICE_ID_HIFN_7956         0x001d

/* I/O region sizes */

#define HIFN_BAR0_SIZE                  0x1000
#define HIFN_BAR1_SIZE                  0x2000
#define HIFN_BAR2_SIZE                  0x8000

/* DMA registres */

#define HIFN_DMA_CRA                    0x0C    /* DMA Command Ring Address */
#define HIFN_DMA_SDRA                   0x1C    /* DMA Source Data Ring Address */
#define HIFN_DMA_RRA                    0x2C    /* DMA Result Ring Address */
#define HIFN_DMA_DDRA                   0x3C    /* DMA Destination Data Ring Address */
#define HIFN_DMA_STCTL                  0x40    /* DMA Status and Control */
#define HIFN_DMA_INTREN                 0x44    /* DMA Interrupt Enable */
#define HIFN_DMA_CFG1                   0x48    /* DMA Configuration #1 */
#define HIFN_DMA_CFG2                   0x6C    /* DMA Configuration #2 */
#define HIFN_CHIP_ID                    0x98    /* Chip ID */

/*
 * Processing Unit Registers (offset from BASEREG0)
 */
#define HIFN_0_PUDATA           0x00    /* Processing Unit Data */
#define HIFN_0_PUCTRL           0x04    /* Processing Unit Control */
#define HIFN_0_PUISR            0x08    /* Processing Unit Interrupt Status */
#define HIFN_0_PUCNFG           0x0c    /* Processing Unit Configuration */
#define HIFN_0_PUIER            0x10    /* Processing Unit Interrupt Enable */
#define HIFN_0_PUSTAT           0x14    /* Processing Unit Status/Chip ID */
#define HIFN_0_FIFOSTAT         0x18    /* FIFO Status */
#define HIFN_0_FIFOCNFG         0x1c    /* FIFO Configuration */
#define HIFN_0_SPACESIZE        0x20    /* Register space size */

/* Processing Unit Control Register (HIFN_0_PUCTRL) */
#define HIFN_PUCTRL_CLRSRCFIFO  0x0010  /* clear source fifo */
#define HIFN_PUCTRL_STOP        0x0008  /* stop pu */
#define HIFN_PUCTRL_LOCKRAM     0x0004  /* lock ram */
#define HIFN_PUCTRL_DMAENA      0x0002  /* enable dma */
#define HIFN_PUCTRL_RESET       0x0001  /* Reset processing unit */

/* Processing Unit Interrupt Status Register (HIFN_0_PUISR) */
#define HIFN_PUISR_CMDINVAL     0x8000  /* Invalid command interrupt */
#define HIFN_PUISR_DATAERR      0x4000  /* Data error interrupt */
#define HIFN_PUISR_SRCFIFO      0x2000  /* Source FIFO ready interrupt */
#define HIFN_PUISR_DSTFIFO      0x1000  /* Destination FIFO ready interrupt */
#define HIFN_PUISR_DSTOVER      0x0200  /* Destination overrun interrupt */
#define HIFN_PUISR_SRCCMD       0x0080  /* Source command interrupt */
#define HIFN_PUISR_SRCCTX       0x0040  /* Source context interrupt */
#define HIFN_PUISR_SRCDATA      0x0020  /* Source data interrupt */
#define HIFN_PUISR_DSTDATA      0x0010  /* Destination data interrupt */
#define HIFN_PUISR_DSTRESULT    0x0004  /* Destination result interrupt */

/* Processing Unit Configuration Register (HIFN_0_PUCNFG) */
#define HIFN_PUCNFG_DRAMMASK    0xe000  /* DRAM size mask */
#define HIFN_PUCNFG_DSZ_256K    0x0000  /* 256k dram */
#define HIFN_PUCNFG_DSZ_512K    0x2000  /* 512k dram */
#define HIFN_PUCNFG_DSZ_1M      0x4000  /* 1m dram */
#define HIFN_PUCNFG_DSZ_2M      0x6000  /* 2m dram */
#define HIFN_PUCNFG_DSZ_4M      0x8000  /* 4m dram */
#define HIFN_PUCNFG_DSZ_8M      0xa000  /* 8m dram */
#define HIFN_PUNCFG_DSZ_16M     0xc000  /* 16m dram */
#define HIFN_PUCNFG_DSZ_32M     0xe000  /* 32m dram */
#define HIFN_PUCNFG_DRAMREFRESH 0x1800  /* DRAM refresh rate mask */
#define HIFN_PUCNFG_DRFR_512    0x0000  /* 512 divisor of ECLK */
#define HIFN_PUCNFG_DRFR_256    0x0800  /* 256 divisor of ECLK */
#define HIFN_PUCNFG_DRFR_128    0x1000  /* 128 divisor of ECLK */
#define HIFN_PUCNFG_TCALLPHASES 0x0200  /* your guess is as good as mine... */
#define HIFN_PUCNFG_TCDRVTOTEM  0x0100  /* your guess is as good as mine... */
#define HIFN_PUCNFG_BIGENDIAN   0x0080  /* DMA big endian mode */
#define HIFN_PUCNFG_BUS32       0x0040  /* Bus width 32bits */
#define HIFN_PUCNFG_BUS16       0x0000  /* Bus width 16 bits */
#define HIFN_PUCNFG_CHIPID      0x0020  /* Allow chipid from PUSTAT */
#define HIFN_PUCNFG_DRAM        0x0010  /* Context RAM is DRAM */
#define HIFN_PUCNFG_SRAM        0x0000  /* Context RAM is SRAM */
#define HIFN_PUCNFG_COMPSING    0x0004  /* Enable single compression context */
#define HIFN_PUCNFG_ENCCNFG     0x0002  /* Encryption configuration */

/* Processing Unit Interrupt Enable Register (HIFN_0_PUIER) */
#define HIFN_PUIER_CMDINVAL     0x8000  /* Invalid command interrupt */
#define HIFN_PUIER_DATAERR      0x4000  /* Data error interrupt */
#define HIFN_PUIER_SRCFIFO      0x2000  /* Source FIFO ready interrupt */
#define HIFN_PUIER_DSTFIFO      0x1000  /* Destination FIFO ready interrupt */
#define HIFN_PUIER_DSTOVER      0x0200  /* Destination overrun interrupt */
#define HIFN_PUIER_SRCCMD       0x0080  /* Source command interrupt */
#define HIFN_PUIER_SRCCTX       0x0040  /* Source context interrupt */
#define HIFN_PUIER_SRCDATA      0x0020  /* Source data interrupt */
#define HIFN_PUIER_DSTDATA      0x0010  /* Destination data interrupt */
#define HIFN_PUIER_DSTRESULT    0x0004  /* Destination result interrupt */

/* Processing Unit Status Register/Chip ID (HIFN_0_PUSTAT) */
#define HIFN_PUSTAT_CMDINVAL    0x8000  /* Invalid command interrupt */
#define HIFN_PUSTAT_DATAERR     0x4000  /* Data error interrupt */
#define HIFN_PUSTAT_SRCFIFO     0x2000  /* Source FIFO ready interrupt */
#define HIFN_PUSTAT_DSTFIFO     0x1000  /* Destination FIFO ready interrupt */
#define HIFN_PUSTAT_DSTOVER     0x0200  /* Destination overrun interrupt */
#define HIFN_PUSTAT_SRCCMD      0x0080  /* Source command interrupt */
#define HIFN_PUSTAT_SRCCTX      0x0040  /* Source context interrupt */
#define HIFN_PUSTAT_SRCDATA     0x0020  /* Source data interrupt */
#define HIFN_PUSTAT_DSTDATA     0x0010  /* Destination data interrupt */
#define HIFN_PUSTAT_DSTRESULT   0x0004  /* Destination result interrupt */
#define HIFN_PUSTAT_CHIPREV     0x00ff  /* Chip revision mask */
#define HIFN_PUSTAT_CHIPENA     0xff00  /* Chip enabled mask */
#define HIFN_PUSTAT_ENA_2       0x1100  /* Level 2 enabled */
#define HIFN_PUSTAT_ENA_1       0x1000  /* Level 1 enabled */
#define HIFN_PUSTAT_ENA_0       0x3000  /* Level 0 enabled */
#define HIFN_PUSTAT_REV_2       0x0020  /* 7751 PT6/2 */
#define HIFN_PUSTAT_REV_3       0x0030  /* 7751 PT6/3 */

/* FIFO Status Register (HIFN_0_FIFOSTAT) */
#define HIFN_FIFOSTAT_SRC       0x7f00  /* Source FIFO available */
#define HIFN_FIFOSTAT_DST       0x007f  /* Destination FIFO available */

/* FIFO Configuration Register (HIFN_0_FIFOCNFG) */
#define HIFN_FIFOCNFG_THRESHOLD 0x0400  /* must be written as 1 */

/*
 * DMA Interface Registers (offset from BASEREG1)
 */
#define HIFN_1_DMA_CRAR         0x0c    /* DMA Command Ring Address */
#define HIFN_1_DMA_SRAR         0x1c    /* DMA Source Ring Address */
#define HIFN_1_DMA_RRAR         0x2c    /* DMA Result Ring Address */
#define HIFN_1_DMA_DRAR         0x3c    /* DMA Destination Ring Address */
#define HIFN_1_DMA_CSR          0x40    /* DMA Status and Control */
#define HIFN_1_DMA_IER          0x44    /* DMA Interrupt Enable */
#define HIFN_1_DMA_CNFG         0x48    /* DMA Configuration */
#define HIFN_1_PLL              0x4c    /* 795x: PLL config */
#define HIFN_1_7811_RNGENA      0x60    /* 7811: rng enable */
#define HIFN_1_7811_RNGCFG      0x64    /* 7811: rng config */
#define HIFN_1_7811_RNGDAT      0x68    /* 7811: rng data */
#define HIFN_1_7811_RNGSTS      0x6c    /* 7811: rng status */
#define HIFN_1_7811_MIPSRST     0x94    /* 7811: MIPS reset */
#define HIFN_1_REVID            0x98    /* Revision ID */
#define HIFN_1_UNLOCK_SECRET1   0xf4
#define HIFN_1_UNLOCK_SECRET2   0xfc
#define HIFN_1_PUB_RESET        0x204   /* Public/RNG Reset */
#define HIFN_1_PUB_BASE         0x300   /* Public Base Address */
#define HIFN_1_PUB_OPLEN        0x304   /* Public Operand Length */
#define HIFN_1_PUB_OP           0x308   /* Public Operand */
#define HIFN_1_PUB_STATUS       0x30c   /* Public Status */
#define HIFN_1_PUB_IEN          0x310   /* Public Interrupt enable */
#define HIFN_1_RNG_CONFIG       0x314   /* RNG config */
#define HIFN_1_RNG_DATA         0x318   /* RNG data */
#define HIFN_1_PUB_MEM          0x400   /* start of Public key memory */
#define HIFN_1_PUB_MEMEND       0xbff   /* end of Public key memory */

/* DMA Status and Control Register (HIFN_1_DMA_CSR) */
#define HIFN_DMACSR_D_CTRLMASK  0xc0000000      /* Destinition Ring Control */
#define HIFN_DMACSR_D_CTRL_NOP  0x00000000      /* Dest. Control: no-op */
#define HIFN_DMACSR_D_CTRL_DIS  0x40000000      /* Dest. Control: disable */
#define HIFN_DMACSR_D_CTRL_ENA  0x80000000      /* Dest. Control: enable */
#define HIFN_DMACSR_D_ABORT     0x20000000      /* Destinition Ring PCIAbort */
#define HIFN_DMACSR_D_DONE      0x10000000      /* Destinition Ring Done */
#define HIFN_DMACSR_D_LAST      0x08000000      /* Destinition Ring Last */
#define HIFN_DMACSR_D_WAIT      0x04000000      /* Destinition Ring Waiting */
#define HIFN_DMACSR_D_OVER      0x02000000      /* Destinition Ring Overflow */
#define HIFN_DMACSR_R_CTRL      0x00c00000      /* Result Ring Control */
#define HIFN_DMACSR_R_CTRL_NOP  0x00000000      /* Result Control: no-op */
#define HIFN_DMACSR_R_CTRL_DIS  0x00400000      /* Result Control: disable */
#define HIFN_DMACSR_R_CTRL_ENA  0x00800000      /* Result Control: enable */
#define HIFN_DMACSR_R_ABORT     0x00200000      /* Result Ring PCI Abort */
#define HIFN_DMACSR_R_DONE      0x00100000      /* Result Ring Done */
#define HIFN_DMACSR_R_LAST      0x00080000      /* Result Ring Last */
#define HIFN_DMACSR_R_WAIT      0x00040000      /* Result Ring Waiting */
#define HIFN_DMACSR_R_OVER      0x00020000      /* Result Ring Overflow */
#define HIFN_DMACSR_S_CTRL      0x0000c000      /* Source Ring Control */
#define HIFN_DMACSR_S_CTRL_NOP  0x00000000      /* Source Control: no-op */
#define HIFN_DMACSR_S_CTRL_DIS  0x00004000      /* Source Control: disable */
#define HIFN_DMACSR_S_CTRL_ENA  0x00008000      /* Source Control: enable */
#define HIFN_DMACSR_S_ABORT     0x00002000      /* Source Ring PCI Abort */
#define HIFN_DMACSR_S_DONE      0x00001000      /* Source Ring Done */
#define HIFN_DMACSR_S_LAST      0x00000800      /* Source Ring Last */
#define HIFN_DMACSR_S_WAIT      0x00000400      /* Source Ring Waiting */
#define HIFN_DMACSR_ILLW        0x00000200      /* Illegal write (7811 only) */
#define HIFN_DMACSR_ILLR        0x00000100      /* Illegal read (7811 only) */
#define HIFN_DMACSR_C_CTRL      0x000000c0      /* Command Ring Control */
#define HIFN_DMACSR_C_CTRL_NOP  0x00000000      /* Command Control: no-op */
#define HIFN_DMACSR_C_CTRL_DIS  0x00000040      /* Command Control: disable */
#define HIFN_DMACSR_C_CTRL_ENA  0x00000080      /* Command Control: enable */
#define HIFN_DMACSR_C_ABORT     0x00000020      /* Command Ring PCI Abort */
#define HIFN_DMACSR_C_DONE      0x00000010      /* Command Ring Done */
#define HIFN_DMACSR_C_LAST      0x00000008      /* Command Ring Last */
#define HIFN_DMACSR_C_WAIT      0x00000004      /* Command Ring Waiting */
#define HIFN_DMACSR_PUBDONE     0x00000002      /* Public op done (7951 only) */
#define HIFN_DMACSR_ENGINE      0x00000001      /* Command Ring Engine IRQ */

/* DMA Interrupt Enable Register (HIFN_1_DMA_IER) */
#define HIFN_DMAIER_D_ABORT     0x20000000      /* Destination Ring PCIAbort */
#define HIFN_DMAIER_D_DONE      0x10000000      /* Destination Ring Done */
#define HIFN_DMAIER_D_LAST      0x08000000      /* Destination Ring Last */
#define HIFN_DMAIER_D_WAIT      0x04000000      /* Destination Ring Waiting */
#define HIFN_DMAIER_D_OVER      0x02000000      /* Destination Ring Overflow */
#define HIFN_DMAIER_R_ABORT     0x00200000      /* Result Ring PCI Abort */
#define HIFN_DMAIER_R_DONE      0x00100000      /* Result Ring Done */
#define HIFN_DMAIER_R_LAST      0x00080000      /* Result Ring Last */
#define HIFN_DMAIER_R_WAIT      0x00040000      /* Result Ring Waiting */
#define HIFN_DMAIER_R_OVER      0x00020000      /* Result Ring Overflow */
#define HIFN_DMAIER_S_ABORT     0x00002000      /* Source Ring PCI Abort */
#define HIFN_DMAIER_S_DONE      0x00001000      /* Source Ring Done */
#define HIFN_DMAIER_S_LAST      0x00000800      /* Source Ring Last */
#define HIFN_DMAIER_S_WAIT      0x00000400      /* Source Ring Waiting */
#define HIFN_DMAIER_ILLW        0x00000200      /* Illegal write (7811 only) */
#define HIFN_DMAIER_ILLR        0x00000100      /* Illegal read (7811 only) */
#define HIFN_DMAIER_C_ABORT     0x00000020      /* Command Ring PCI Abort */
#define HIFN_DMAIER_C_DONE      0x00000010      /* Command Ring Done */
#define HIFN_DMAIER_C_LAST      0x00000008      /* Command Ring Last */
#define HIFN_DMAIER_C_WAIT      0x00000004      /* Command Ring Waiting */
#define HIFN_DMAIER_PUBDONE     0x00000002      /* public op done (7951 only) */
#define HIFN_DMAIER_ENGINE      0x00000001      /* Engine IRQ */

/* DMA Configuration Register (HIFN_1_DMA_CNFG) */
#define HIFN_DMACNFG_BIGENDIAN  0x10000000      /* big endian mode */
#define HIFN_DMACNFG_POLLFREQ   0x00ff0000      /* Poll frequency mask */
#define HIFN_DMACNFG_UNLOCK     0x00000800
#define HIFN_DMACNFG_POLLINVAL  0x00000700      /* Invalid Poll Scalar */
#define HIFN_DMACNFG_LAST       0x00000010      /* Host control LAST bit */
#define HIFN_DMACNFG_MODE       0x00000004      /* DMA mode */
#define HIFN_DMACNFG_DMARESET   0x00000002      /* DMA Reset # */
#define HIFN_DMACNFG_MSTRESET   0x00000001      /* Master Reset # */

/* PLL configuration register */
#define HIFN_PLL_REF_CLK_HBI    0x00000000      /* HBI reference clock */
#define HIFN_PLL_REF_CLK_PLL    0x00000001      /* PLL reference clock */
#define HIFN_PLL_BP             0x00000002      /* Reference clock bypass */
#define HIFN_PLL_PK_CLK_HBI     0x00000000      /* PK engine HBI clock */
#define HIFN_PLL_PK_CLK_PLL     0x00000008      /* PK engine PLL clock */
#define HIFN_PLL_PE_CLK_HBI     0x00000000      /* PE engine HBI clock */
#define HIFN_PLL_PE_CLK_PLL     0x00000010      /* PE engine PLL clock */
#define HIFN_PLL_RESERVED_1     0x00000400      /* Reserved bit, must be 1 */
#define HIFN_PLL_ND_SHIFT       11              /* Clock multiplier shift */
#define HIFN_PLL_ND_MULT_2      0x00000000      /* PLL clock multiplier 2 */
#define HIFN_PLL_ND_MULT_4      0x00000800      /* PLL clock multiplier 4 */
#define HIFN_PLL_ND_MULT_6      0x00001000      /* PLL clock multiplier 6 */
#define HIFN_PLL_ND_MULT_8      0x00001800      /* PLL clock multiplier 8 */
#define HIFN_PLL_ND_MULT_10     0x00002000      /* PLL clock multiplier 10 */
#define HIFN_PLL_ND_MULT_12     0x00002800      /* PLL clock multiplier 12 */
#define HIFN_PLL_IS_1_8         0x00000000      /* charge pump (mult. 1-8) */
#define HIFN_PLL_IS_9_12        0x00010000      /* charge pump (mult. 9-12) */

#define HIFN_PLL_FCK_MAX        266             /* Maximum PLL frequency */

/* Public key reset register (HIFN_1_PUB_RESET) */
#define HIFN_PUBRST_RESET       0x00000001      /* reset public/rng unit */

/* Public base address register (HIFN_1_PUB_BASE) */
#define HIFN_PUBBASE_ADDR       0x00003fff      /* base address */

/* Public operand length register (HIFN_1_PUB_OPLEN) */
#define HIFN_PUBOPLEN_MOD_M     0x0000007f      /* modulus length mask */
#define HIFN_PUBOPLEN_MOD_S     0               /* modulus length shift */
#define HIFN_PUBOPLEN_EXP_M     0x0003ff80      /* exponent length mask */
#define HIFN_PUBOPLEN_EXP_S     7               /* exponent length shift */
#define HIFN_PUBOPLEN_RED_M     0x003c0000      /* reducend length mask */
#define HIFN_PUBOPLEN_RED_S     18              /* reducend length shift */

/* Public operation register (HIFN_1_PUB_OP) */
#define HIFN_PUBOP_AOFFSET_M    0x0000007f      /* A offset mask */
#define HIFN_PUBOP_AOFFSET_S    0               /* A offset shift */
#define HIFN_PUBOP_BOFFSET_M    0x00000f80      /* B offset mask */
#define HIFN_PUBOP_BOFFSET_S    7               /* B offset shift */
#define HIFN_PUBOP_MOFFSET_M    0x0003f000      /* M offset mask */
#define HIFN_PUBOP_MOFFSET_S    12              /* M offset shift */
#define HIFN_PUBOP_OP_MASK      0x003c0000      /* Opcode: */
#define HIFN_PUBOP_OP_NOP       0x00000000      /*  NOP */
#define HIFN_PUBOP_OP_ADD       0x00040000      /*  ADD */
#define HIFN_PUBOP_OP_ADDC      0x00080000      /*  ADD w/carry */
#define HIFN_PUBOP_OP_SUB       0x000c0000      /*  SUB */
#define HIFN_PUBOP_OP_SUBC      0x00100000      /*  SUB w/carry */
#define HIFN_PUBOP_OP_MODADD    0x00140000      /*  Modular ADD */
#define HIFN_PUBOP_OP_MODSUB    0x00180000      /*  Modular SUB */
#define HIFN_PUBOP_OP_INCA      0x001c0000      /*  INC A */
#define HIFN_PUBOP_OP_DECA      0x00200000      /*  DEC A */
#define HIFN_PUBOP_OP_MULT      0x00240000      /*  MULT */
#define HIFN_PUBOP_OP_MODMULT   0x00280000      /*  Modular MULT */
#define HIFN_PUBOP_OP_MODRED    0x002c0000      /*  Modular RED */
#define HIFN_PUBOP_OP_MODEXP    0x00300000      /*  Modular EXP */

/* Public status register (HIFN_1_PUB_STATUS) */
#define HIFN_PUBSTS_DONE        0x00000001      /* operation done */
#define HIFN_PUBSTS_CARRY       0x00000002      /* carry */

/* Public interrupt enable register (HIFN_1_PUB_IEN) */
#define HIFN_PUBIEN_DONE        0x00000001      /* operation done interrupt */

/* Random number generator config register (HIFN_1_RNG_CONFIG) */
#define HIFN_RNGCFG_ENA         0x00000001      /* enable rng */

#define HIFN_NAMESIZE                   32
#define HIFN_MAX_RESULT_ORDER           5

#define HIFN_D_CMD_RSIZE                (24 * 1)
#define HIFN_D_SRC_RSIZE                (80 * 1)
#define HIFN_D_DST_RSIZE                (80 * 1)
#define HIFN_D_RES_RSIZE                (24 * 1)

#define HIFN_D_DST_DALIGN               4

#define HIFN_QUEUE_LENGTH               (HIFN_D_CMD_RSIZE - 1)

#define AES_MIN_KEY_SIZE                16
#define AES_MAX_KEY_SIZE                32

#define HIFN_DES_KEY_LENGTH             8
#define HIFN_3DES_KEY_LENGTH            24
#define HIFN_MAX_CRYPT_KEY_LENGTH       AES_MAX_KEY_SIZE
#define HIFN_IV_LENGTH                  8
#define HIFN_AES_IV_LENGTH              16
#define HIFN_MAX_IV_LENGTH              HIFN_AES_IV_LENGTH

#define HIFN_MAC_KEY_LENGTH             64
#define HIFN_MD5_LENGTH                 16
#define HIFN_SHA1_LENGTH                20
#define HIFN_MAC_TRUNC_LENGTH           12

#define HIFN_MAX_COMMAND                (8 + 8 + 8 + 64 + 260)
#define HIFN_MAX_RESULT                 (8 + 4 + 4 + 20 + 4)
#define HIFN_USED_RESULT                12

struct hifn_desc {
        volatile __le32         l;
        volatile __le32         p;
};

struct hifn_dma {
        struct hifn_desc        cmdr[HIFN_D_CMD_RSIZE + 1];
        struct hifn_desc        srcr[HIFN_D_SRC_RSIZE + 1];
        struct hifn_desc        dstr[HIFN_D_DST_RSIZE + 1];
        struct hifn_desc        resr[HIFN_D_RES_RSIZE + 1];

        u8                      command_bufs[HIFN_D_CMD_RSIZE][HIFN_MAX_COMMAND];
        u8                      result_bufs[HIFN_D_CMD_RSIZE][HIFN_MAX_RESULT];

        /*
         *  Our current positions for insertion and removal from the descriptor
         *  rings.
         */
        volatile int            cmdi, srci, dsti, resi;
        volatile int            cmdu, srcu, dstu, resu;
        int                     cmdk, srck, dstk, resk;
};

#define HIFN_FLAG_CMD_BUSY      (1 << 0)
#define HIFN_FLAG_SRC_BUSY      (1 << 1)
#define HIFN_FLAG_DST_BUSY      (1 << 2)
#define HIFN_FLAG_RES_BUSY      (1 << 3)
#define HIFN_FLAG_OLD_KEY       (1 << 4)

#define HIFN_DEFAULT_ACTIVE_NUM 5

struct hifn_device {
        char                    name[HIFN_NAMESIZE];

        int                     irq;

        struct pci_dev          *pdev;
        void __iomem            *bar[3];

        void                    *desc_virt;
        dma_addr_t              desc_dma;

        u32                     dmareg;

        void                    *sa[HIFN_D_RES_RSIZE];

        spinlock_t              lock;

        u32                     flags;
        int                     active, started;
        struct delayed_work     work;
        unsigned long           reset;
        unsigned long           success;
        unsigned long           prev_success;

        u8                      snum;

        struct tasklet_struct   tasklet;

        struct crypto_queue     queue;
        struct list_head        alg_list;

        unsigned int            pk_clk_freq;

#ifdef CONFIG_CRYPTO_DEV_HIFN_795X_RNG
        unsigned int            rng_wait_time;
        ktime_t                 rngtime;
        struct hwrng            rng;
#endif
};

#define HIFN_D_LENGTH                   0x0000ffff
#define HIFN_D_NOINVALID                0x01000000
#define HIFN_D_MASKDONEIRQ              0x02000000
#define HIFN_D_DESTOVER                 0x04000000
#define HIFN_D_OVER                     0x08000000
#define HIFN_D_LAST                     0x20000000
#define HIFN_D_JUMP                     0x40000000
#define HIFN_D_VALID                    0x80000000

struct hifn_base_command {
        volatile __le16         masks;
        volatile __le16         session_num;
        volatile __le16         total_source_count;
        volatile __le16         total_dest_count;
};

#define HIFN_BASE_CMD_COMP              0x0100  /* enable compression engine */
#define HIFN_BASE_CMD_PAD               0x0200  /* enable padding engine */
#define HIFN_BASE_CMD_MAC               0x0400  /* enable MAC engine */
#define HIFN_BASE_CMD_CRYPT             0x0800  /* enable crypt engine */
#define HIFN_BASE_CMD_DECODE            0x2000
#define HIFN_BASE_CMD_SRCLEN_M          0xc000
#define HIFN_BASE_CMD_SRCLEN_S          14
#define HIFN_BASE_CMD_DSTLEN_M          0x3000
#define HIFN_BASE_CMD_DSTLEN_S          12
#define HIFN_BASE_CMD_LENMASK_HI        0x30000
#define HIFN_BASE_CMD_LENMASK_LO        0x0ffff

/*
 * Structure to help build up the command data structure.
 */
struct hifn_crypt_command {
        volatile __le16         masks;
        volatile __le16         header_skip;
        volatile __le16         source_count;
        volatile __le16         reserved;
};

#define HIFN_CRYPT_CMD_ALG_MASK         0x0003          /* algorithm: */
#define HIFN_CRYPT_CMD_ALG_DES          0x0000          /*   DES */
#define HIFN_CRYPT_CMD_ALG_3DES         0x0001          /*   3DES */
#define HIFN_CRYPT_CMD_ALG_RC4          0x0002          /*   RC4 */
#define HIFN_CRYPT_CMD_ALG_AES          0x0003          /*   AES */
#define HIFN_CRYPT_CMD_MODE_MASK        0x0018          /* Encrypt mode: */
#define HIFN_CRYPT_CMD_MODE_ECB         0x0000          /*   ECB */
#define HIFN_CRYPT_CMD_MODE_CBC         0x0008          /*   CBC */
#define HIFN_CRYPT_CMD_MODE_CFB         0x0010          /*   CFB */
#define HIFN_CRYPT_CMD_MODE_OFB         0x0018          /*   OFB */
#define HIFN_CRYPT_CMD_CLR_CTX          0x0040          /* clear context */
#define HIFN_CRYPT_CMD_KSZ_MASK         0x0600          /* AES key size: */
#define HIFN_CRYPT_CMD_KSZ_128          0x0000          /*  128 bit */
#define HIFN_CRYPT_CMD_KSZ_192          0x0200          /*  192 bit */
#define HIFN_CRYPT_CMD_KSZ_256          0x0400          /*  256 bit */
#define HIFN_CRYPT_CMD_NEW_KEY          0x0800          /* expect new key */
#define HIFN_CRYPT_CMD_NEW_IV           0x1000          /* expect new iv */
#define HIFN_CRYPT_CMD_SRCLEN_M         0xc000
#define HIFN_CRYPT_CMD_SRCLEN_S         14

/*
 * Structure to help build up the command data structure.
 */
struct hifn_mac_command {
        volatile __le16 masks;
        volatile __le16 header_skip;
        volatile __le16 source_count;
        volatile __le16 reserved;
};

#define HIFN_MAC_CMD_ALG_MASK           0x0001
#define HIFN_MAC_CMD_ALG_SHA1           0x0000
#define HIFN_MAC_CMD_ALG_MD5            0x0001
#define HIFN_MAC_CMD_MODE_MASK          0x000c
#define HIFN_MAC_CMD_MODE_HMAC          0x0000
#define HIFN_MAC_CMD_MODE_SSL_MAC       0x0004
#define HIFN_MAC_CMD_MODE_HASH          0x0008
#define HIFN_MAC_CMD_MODE_FULL          0x0004
#define HIFN_MAC_CMD_TRUNC              0x0010
#define HIFN_MAC_CMD_RESULT             0x0020
#define HIFN_MAC_CMD_APPEND             0x0040
#define HIFN_MAC_CMD_SRCLEN_M           0xc000
#define HIFN_MAC_CMD_SRCLEN_S           14

/*
 * MAC POS IPsec initiates authentication after encryption on encodes
 * and before decryption on decodes.
 */
#define HIFN_MAC_CMD_POS_IPSEC          0x0200
#define HIFN_MAC_CMD_NEW_KEY            0x0800

struct hifn_comp_command {
        volatile __le16         masks;
        volatile __le16         header_skip;
        volatile __le16         source_count;
        volatile __le16         reserved;
};

#define HIFN_COMP_CMD_SRCLEN_M          0xc000
#define HIFN_COMP_CMD_SRCLEN_S          14
#define HIFN_COMP_CMD_ONE               0x0100  /* must be one */
#define HIFN_COMP_CMD_CLEARHIST         0x0010  /* clear history */
#define HIFN_COMP_CMD_UPDATEHIST        0x0008  /* update history */
#define HIFN_COMP_CMD_LZS_STRIP0        0x0004  /* LZS: strip zero */
#define HIFN_COMP_CMD_MPPC_RESTART      0x0004  /* MPPC: restart */
#define HIFN_COMP_CMD_ALG_MASK          0x0001  /* compression mode: */
#define HIFN_COMP_CMD_ALG_MPPC          0x0001  /*   MPPC */
#define HIFN_COMP_CMD_ALG_LZS           0x0000  /*   LZS */

struct hifn_base_result {
        volatile __le16         flags;
        volatile __le16         session;
        volatile __le16         src_cnt;                /* 15:0 of source count */
        volatile __le16         dst_cnt;                /* 15:0 of dest count */
};

#define HIFN_BASE_RES_DSTOVERRUN        0x0200  /* destination overrun */
#define HIFN_BASE_RES_SRCLEN_M          0xc000  /* 17:16 of source count */
#define HIFN_BASE_RES_SRCLEN_S          14
#define HIFN_BASE_RES_DSTLEN_M          0x3000  /* 17:16 of dest count */
#define HIFN_BASE_RES_DSTLEN_S          12

struct hifn_comp_result {
        volatile __le16         flags;
        volatile __le16         crc;
};

#define HIFN_COMP_RES_LCB_M             0xff00  /* longitudinal check byte */
#define HIFN_COMP_RES_LCB_S             8
#define HIFN_COMP_RES_RESTART           0x0004  /* MPPC: restart */
#define HIFN_COMP_RES_ENDMARKER         0x0002  /* LZS: end marker seen */
#define HIFN_COMP_RES_SRC_NOTZERO       0x0001  /* source expired */

struct hifn_mac_result {
        volatile __le16         flags;
        volatile __le16         reserved;
        /* followed by 0, 6, 8, or 10 u16's of the MAC, then crypt */
};

#define HIFN_MAC_RES_MISCOMPARE         0x0002  /* compare failed */
#define HIFN_MAC_RES_SRC_NOTZERO        0x0001  /* source expired */

struct hifn_crypt_result {
        volatile __le16         flags;
        volatile __le16         reserved;
};

#define HIFN_CRYPT_RES_SRC_NOTZERO      0x0001  /* source expired */

#ifndef HIFN_POLL_FREQUENCY
#define HIFN_POLL_FREQUENCY     0x1
#endif

#ifndef HIFN_POLL_SCALAR
#define HIFN_POLL_SCALAR        0x0
#endif

#define HIFN_MAX_SEGLEN         0xffff          /* maximum dma segment len */
#define HIFN_MAX_DMALEN         0x3ffff         /* maximum dma length */

struct hifn_crypto_alg {
        struct list_head        entry;
        struct skcipher_alg     alg;
        struct hifn_device      *dev;
};

#define ASYNC_SCATTERLIST_CACHE 16

#define ASYNC_FLAGS_MISALIGNED  (1 << 0)

struct hifn_cipher_walk {
        struct scatterlist      cache[ASYNC_SCATTERLIST_CACHE];
        u32                     flags;
        int                     num;
};

struct hifn_context {
        u8                      key[HIFN_MAX_CRYPT_KEY_LENGTH];
        struct hifn_device      *dev;
        unsigned int            keysize;
};

struct hifn_request_context {
        u8                      *iv;
        unsigned int            ivsize;
        u8                      op, type, mode, unused;
        struct hifn_cipher_walk walk;
};

#define crypto_alg_to_hifn(a)   container_of(a, struct hifn_crypto_alg, alg)

static inline u32 hifn_read_0(struct hifn_device *dev, u32 reg)
{
        return readl(dev->bar[0] + reg);
}

static inline u32 hifn_read_1(struct hifn_device *dev, u32 reg)
{
        return readl(dev->bar[1] + reg);
}

static inline void hifn_write_0(struct hifn_device *dev, u32 reg, u32 val)
{
        writel((__force u32)cpu_to_le32(val), dev->bar[0] + reg);
}

static inline void hifn_write_1(struct hifn_device *dev, u32 reg, u32 val)
{
        writel((__force u32)cpu_to_le32(val), dev->bar[1] + reg);
}

static void hifn_wait_puc(struct hifn_device *dev)
{
        int i;
        u32 ret;

        for (i = 10000; i > 0; --i) {
                ret = hifn_read_0(dev, HIFN_0_PUCTRL);
                if (!(ret & HIFN_PUCTRL_RESET))
                        break;

                udelay(1);
        }

        if (!i)
                dev_err(&dev->pdev->dev, "Failed to reset PUC unit.\n");
}

static void hifn_reset_puc(struct hifn_device *dev)
{
        hifn_write_0(dev, HIFN_0_PUCTRL, HIFN_PUCTRL_DMAENA);
        hifn_wait_puc(dev);
}

static void hifn_stop_device(struct hifn_device *dev)
{
        hifn_write_1(dev, HIFN_1_DMA_CSR,
                HIFN_DMACSR_D_CTRL_DIS | HIFN_DMACSR_R_CTRL_DIS |
                HIFN_DMACSR_S_CTRL_DIS | HIFN_DMACSR_C_CTRL_DIS);
        hifn_write_0(dev, HIFN_0_PUIER, 0);
        hifn_write_1(dev, HIFN_1_DMA_IER, 0);
}

static void hifn_reset_dma(struct hifn_device *dev, int full)
{
        hifn_stop_device(dev);

        /*
         * Setting poll frequency and others to 0.
         */
        hifn_write_1(dev, HIFN_1_DMA_CNFG, HIFN_DMACNFG_MSTRESET |
                        HIFN_DMACNFG_DMARESET | HIFN_DMACNFG_MODE);
        mdelay(1);

        /*
         * Reset DMA.
         */
        if (full) {
                hifn_write_1(dev, HIFN_1_DMA_CNFG, HIFN_DMACNFG_MODE);
                mdelay(1);
        } else {
                hifn_write_1(dev, HIFN_1_DMA_CNFG, HIFN_DMACNFG_MODE |
                                HIFN_DMACNFG_MSTRESET);
                hifn_reset_puc(dev);
        }

        hifn_write_1(dev, HIFN_1_DMA_CNFG, HIFN_DMACNFG_MSTRESET |
                        HIFN_DMACNFG_DMARESET | HIFN_DMACNFG_MODE);

        hifn_reset_puc(dev);
}

static u32 hifn_next_signature(u32 a, u_int cnt)
{
        int i;
        u32 v;

        for (i = 0; i < cnt; i++) {
                /* get the parity */
                v = a & 0x80080125;
                v ^= v >> 16;
                v ^= v >> 8;
                v ^= v >> 4;
                v ^= v >> 2;
                v ^= v >> 1;

                a = (v & 1) ^ (a << 1);
        }

        return a;
}

static struct pci2id {
        u_short         pci_vendor;
        u_short         pci_prod;
        char            card_id[13];
} pci2id[] = {
        {
                PCI_VENDOR_ID_HIFN,
                PCI_DEVICE_ID_HIFN_7955,
                { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                  0x00, 0x00, 0x00, 0x00, 0x00 }
        },
        {
                PCI_VENDOR_ID_HIFN,
                PCI_DEVICE_ID_HIFN_7956,
                { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                  0x00, 0x00, 0x00, 0x00, 0x00 }
        }
};

#ifdef CONFIG_CRYPTO_DEV_HIFN_795X_RNG
static int hifn_rng_data_present(struct hwrng *rng, int wait)
{
        struct hifn_device *dev = (struct hifn_device *)rng->priv;
        s64 nsec;

        nsec = ktime_to_ns(ktime_sub(ktime_get(), dev->rngtime));
        nsec -= dev->rng_wait_time;
        if (nsec <= 0)
                return 1;
        if (!wait)
                return 0;
        ndelay(nsec);
        return 1;
}

static int hifn_rng_data_read(struct hwrng *rng, u32 *data)
{
        struct hifn_device *dev = (struct hifn_device *)rng->priv;

        *data = hifn_read_1(dev, HIFN_1_RNG_DATA);
        dev->rngtime = ktime_get();
        return 4;
}

static int hifn_register_rng(struct hifn_device *dev)
{
        /*
         * We must wait at least 256 Pk_clk cycles between two reads of the rng.
         */
        dev->rng_wait_time      = DIV_ROUND_UP_ULL(NSEC_PER_SEC,
                                                   dev->pk_clk_freq) * 256;

        dev->rng.name           = dev->name;
        dev->rng.data_present   = hifn_rng_data_present,
        dev->rng.data_read      = hifn_rng_data_read,
        dev->rng.priv           = (unsigned long)dev;

        return hwrng_register(&dev->rng);
}

static void hifn_unregister_rng(struct hifn_device *dev)
{
        hwrng_unregister(&dev->rng);
}
#else
#define hifn_register_rng(dev)          0
#define hifn_unregister_rng(dev)
#endif

static int hifn_init_pubrng(struct hifn_device *dev)
{
        int i;

        hifn_write_1(dev, HIFN_1_PUB_RESET, hifn_read_1(dev, HIFN_1_PUB_RESET) |
                        HIFN_PUBRST_RESET);

        for (i = 100; i > 0; --i) {
                mdelay(1);

                if ((hifn_read_1(dev, HIFN_1_PUB_RESET) & HIFN_PUBRST_RESET) == 0)
                        break;
        }

        if (!i) {
                dev_err(&dev->pdev->dev, "Failed to initialise public key engine.\n");
        } else {
                hifn_write_1(dev, HIFN_1_PUB_IEN, HIFN_PUBIEN_DONE);
                dev->dmareg |= HIFN_DMAIER_PUBDONE;
                hifn_write_1(dev, HIFN_1_DMA_IER, dev->dmareg);

                dev_dbg(&dev->pdev->dev, "Public key engine has been successfully initialised.\n");
        }

        /* Enable RNG engine. */

        hifn_write_1(dev, HIFN_1_RNG_CONFIG,
                        hifn_read_1(dev, HIFN_1_RNG_CONFIG) | HIFN_RNGCFG_ENA);
        dev_dbg(&dev->pdev->dev, "RNG engine has been successfully initialised.\n");

#ifdef CONFIG_CRYPTO_DEV_HIFN_795X_RNG
        /* First value must be discarded */
        hifn_read_1(dev, HIFN_1_RNG_DATA);
        dev->rngtime = ktime_get();
#endif
        return 0;
}

static int hifn_enable_crypto(struct hifn_device *dev)
{
        u32 dmacfg, addr;
        char *offtbl = NULL;
        int i;

        for (i = 0; i < ARRAY_SIZE(pci2id); i++) {
                if (pci2id[i].pci_vendor == dev->pdev->vendor &&
                                pci2id[i].pci_prod == dev->pdev->device) {
                        offtbl = pci2id[i].card_id;
                        break;
                }
        }

        if (!offtbl) {
                dev_err(&dev->pdev->dev, "Unknown card!\n");
                return -ENODEV;
        }

        dmacfg = hifn_read_1(dev, HIFN_1_DMA_CNFG);

        hifn_write_1(dev, HIFN_1_DMA_CNFG,
                        HIFN_DMACNFG_UNLOCK | HIFN_DMACNFG_MSTRESET |
                        HIFN_DMACNFG_DMARESET | HIFN_DMACNFG_MODE);
        mdelay(1);
        addr = hifn_read_1(dev, HIFN_1_UNLOCK_SECRET1);
        mdelay(1);
        hifn_write_1(dev, HIFN_1_UNLOCK_SECRET2, 0);
        mdelay(1);

        for (i = 0; i < 12; ++i) {
                addr = hifn_next_signature(addr, offtbl[i] + 0x101);
                hifn_write_1(dev, HIFN_1_UNLOCK_SECRET2, addr);

                mdelay(1);
        }
        hifn_write_1(dev, HIFN_1_DMA_CNFG, dmacfg);

        dev_dbg(&dev->pdev->dev, "%s %s.\n", dev->name, pci_name(dev->pdev));

        return 0;
}

static void hifn_init_dma(struct hifn_device *dev)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        u32 dptr = dev->desc_dma;
        int i;

        for (i = 0; i < HIFN_D_CMD_RSIZE; ++i)
                dma->cmdr[i].p = __cpu_to_le32(dptr +
                                offsetof(struct hifn_dma, command_bufs[i][0]));
        for (i = 0; i < HIFN_D_RES_RSIZE; ++i)
                dma->resr[i].p = __cpu_to_le32(dptr +
                                offsetof(struct hifn_dma, result_bufs[i][0]));

        /* Setup LAST descriptors. */
        dma->cmdr[HIFN_D_CMD_RSIZE].p = __cpu_to_le32(dptr +
                        offsetof(struct hifn_dma, cmdr[0]));
        dma->srcr[HIFN_D_SRC_RSIZE].p = __cpu_to_le32(dptr +
                        offsetof(struct hifn_dma, srcr[0]));
        dma->dstr[HIFN_D_DST_RSIZE].p = __cpu_to_le32(dptr +
                        offsetof(struct hifn_dma, dstr[0]));
        dma->resr[HIFN_D_RES_RSIZE].p = __cpu_to_le32(dptr +
                        offsetof(struct hifn_dma, resr[0]));

        dma->cmdu = dma->srcu = dma->dstu = dma->resu = 0;
        dma->cmdi = dma->srci = dma->dsti = dma->resi = 0;
        dma->cmdk = dma->srck = dma->dstk = dma->resk = 0;
}

/*
 * Initialize the PLL. We need to know the frequency of the reference clock
 * to calculate the optimal multiplier. For PCI we assume 66MHz, since that
 * allows us to operate without the risk of overclocking the chip. If it
 * actually uses 33MHz, the chip will operate at half the speed, this can be
 * overridden by specifying the frequency as module parameter (pci33).
 *
 * Unfortunately the PCI clock is not very suitable since the HIFN needs a
 * stable clock and the PCI clock frequency may vary, so the default is the
 * external clock. There is no way to find out its frequency, we default to
 * 66MHz since according to Mike Ham of HiFn, almost every board in existence
 * has an external crystal populated at 66MHz.
 */
static void hifn_init_pll(struct hifn_device *dev)
{
        unsigned int freq, m;
        u32 pllcfg;

        pllcfg = HIFN_1_PLL | HIFN_PLL_RESERVED_1;

        if (strncmp(hifn_pll_ref, "ext", 3) == 0)
                pllcfg |= HIFN_PLL_REF_CLK_PLL;
        else
                pllcfg |= HIFN_PLL_REF_CLK_HBI;

        if (hifn_pll_ref[3] != '\0')
                freq = simple_strtoul(hifn_pll_ref + 3, NULL, 10);
        else {
                freq = 66;
                dev_info(&dev->pdev->dev, "assuming %uMHz clock speed, override with hifn_pll_ref=%.3s<frequency>\n",
                         freq, hifn_pll_ref);
        }

        m = HIFN_PLL_FCK_MAX / freq;

        pllcfg |= (m / 2 - 1) << HIFN_PLL_ND_SHIFT;
        if (m <= 8)
                pllcfg |= HIFN_PLL_IS_1_8;
        else
                pllcfg |= HIFN_PLL_IS_9_12;

        /* Select clock source and enable clock bypass */
        hifn_write_1(dev, HIFN_1_PLL, pllcfg |
                     HIFN_PLL_PK_CLK_HBI | HIFN_PLL_PE_CLK_HBI | HIFN_PLL_BP);

        /* Let the chip lock to the input clock */
        mdelay(10);

        /* Disable clock bypass */
        hifn_write_1(dev, HIFN_1_PLL, pllcfg |
                     HIFN_PLL_PK_CLK_HBI | HIFN_PLL_PE_CLK_HBI);

        /* Switch the engines to the PLL */
        hifn_write_1(dev, HIFN_1_PLL, pllcfg |
                     HIFN_PLL_PK_CLK_PLL | HIFN_PLL_PE_CLK_PLL);

        /*
         * The Fpk_clk runs at half the total speed. Its frequency is needed to
         * calculate the minimum time between two reads of the rng. Since 33MHz
         * is actually 33.333... we overestimate the frequency here, resulting
         * in slightly larger intervals.
         */
        dev->pk_clk_freq = 1000000 * (freq + 1) * m / 2;
}

static void hifn_init_registers(struct hifn_device *dev)
{
        u32 dptr = dev->desc_dma;

        /* Initialization magic... */
        hifn_write_0(dev, HIFN_0_PUCTRL, HIFN_PUCTRL_DMAENA);
        hifn_write_0(dev, HIFN_0_FIFOCNFG, HIFN_FIFOCNFG_THRESHOLD);
        hifn_write_0(dev, HIFN_0_PUIER, HIFN_PUIER_DSTOVER);

        /* write all 4 ring address registers */
        hifn_write_1(dev, HIFN_1_DMA_CRAR, dptr +
                                offsetof(struct hifn_dma, cmdr[0]));
        hifn_write_1(dev, HIFN_1_DMA_SRAR, dptr +
                                offsetof(struct hifn_dma, srcr[0]));
        hifn_write_1(dev, HIFN_1_DMA_DRAR, dptr +
                                offsetof(struct hifn_dma, dstr[0]));
        hifn_write_1(dev, HIFN_1_DMA_RRAR, dptr +
                                offsetof(struct hifn_dma, resr[0]));

        mdelay(2);
#if 0
        hifn_write_1(dev, HIFN_1_DMA_CSR,
            HIFN_DMACSR_D_CTRL_DIS | HIFN_DMACSR_R_CTRL_DIS |
            HIFN_DMACSR_S_CTRL_DIS | HIFN_DMACSR_C_CTRL_DIS |
            HIFN_DMACSR_D_ABORT | HIFN_DMACSR_D_DONE | HIFN_DMACSR_D_LAST |
            HIFN_DMACSR_D_WAIT | HIFN_DMACSR_D_OVER |
            HIFN_DMACSR_R_ABORT | HIFN_DMACSR_R_DONE | HIFN_DMACSR_R_LAST |
            HIFN_DMACSR_R_WAIT | HIFN_DMACSR_R_OVER |

            HIFN_DMACSR_S_ABORT | HIFN_DMACSR_S_DONE | HIFN_DMACSR_S_LAST |
            HIFN_DMACSR_S_WAIT |
            HIFN_DMACSR_C_ABORT | HIFN_DMACSR_C_DONE | HIFN_DMACSR_C_LAST |
            HIFN_DMACSR_C_WAIT |
            HIFN_DMACSR_ENGINE |
            HIFN_DMACSR_PUBDONE);
#else
        hifn_write_1(dev, HIFN_1_DMA_CSR,
            HIFN_DMACSR_C_CTRL_ENA | HIFN_DMACSR_S_CTRL_ENA |
            HIFN_DMACSR_D_CTRL_ENA | HIFN_DMACSR_R_CTRL_ENA |
            HIFN_DMACSR_D_ABORT | HIFN_DMACSR_D_DONE | HIFN_DMACSR_D_LAST |
            HIFN_DMACSR_D_WAIT | HIFN_DMACSR_D_OVER |
            HIFN_DMACSR_R_ABORT | HIFN_DMACSR_R_DONE | HIFN_DMACSR_R_LAST |
            HIFN_DMACSR_R_WAIT | HIFN_DMACSR_R_OVER |
            HIFN_DMACSR_S_ABORT | HIFN_DMACSR_S_DONE | HIFN_DMACSR_S_LAST |
            HIFN_DMACSR_S_WAIT |
            HIFN_DMACSR_C_ABORT | HIFN_DMACSR_C_DONE | HIFN_DMACSR_C_LAST |
            HIFN_DMACSR_C_WAIT |
            HIFN_DMACSR_ENGINE |
            HIFN_DMACSR_PUBDONE);
#endif
        hifn_read_1(dev, HIFN_1_DMA_CSR);

        dev->dmareg |= HIFN_DMAIER_R_DONE | HIFN_DMAIER_C_ABORT |
            HIFN_DMAIER_D_OVER | HIFN_DMAIER_R_OVER |
            HIFN_DMAIER_S_ABORT | HIFN_DMAIER_D_ABORT | HIFN_DMAIER_R_ABORT |
            HIFN_DMAIER_ENGINE;
        dev->dmareg &= ~HIFN_DMAIER_C_WAIT;

        hifn_write_1(dev, HIFN_1_DMA_IER, dev->dmareg);
        hifn_read_1(dev, HIFN_1_DMA_IER);
#if 0
        hifn_write_0(dev, HIFN_0_PUCNFG, HIFN_PUCNFG_ENCCNFG |
                    HIFN_PUCNFG_DRFR_128 | HIFN_PUCNFG_TCALLPHASES |
                    HIFN_PUCNFG_TCDRVTOTEM | HIFN_PUCNFG_BUS32 |
                    HIFN_PUCNFG_DRAM);
#else
        hifn_write_0(dev, HIFN_0_PUCNFG, 0x10342);
#endif
        hifn_init_pll(dev);

        hifn_write_0(dev, HIFN_0_PUISR, HIFN_PUISR_DSTOVER);
        hifn_write_1(dev, HIFN_1_DMA_CNFG, HIFN_DMACNFG_MSTRESET |
            HIFN_DMACNFG_DMARESET | HIFN_DMACNFG_MODE | HIFN_DMACNFG_LAST |
            ((HIFN_POLL_FREQUENCY << 16 ) & HIFN_DMACNFG_POLLFREQ) |
            ((HIFN_POLL_SCALAR << 8) & HIFN_DMACNFG_POLLINVAL));
}

static int hifn_setup_base_command(struct hifn_device *dev, u8 *buf,
                unsigned dlen, unsigned slen, u16 mask, u8 snum)
{
        struct hifn_base_command *base_cmd;
        u8 *buf_pos = buf;

        base_cmd = (struct hifn_base_command *)buf_pos;
        base_cmd->masks = __cpu_to_le16(mask);
        base_cmd->total_source_count =
                __cpu_to_le16(slen & HIFN_BASE_CMD_LENMASK_LO);
        base_cmd->total_dest_count =
                __cpu_to_le16(dlen & HIFN_BASE_CMD_LENMASK_LO);

        dlen >>= 16;
        slen >>= 16;
        base_cmd->session_num = __cpu_to_le16(snum |
            ((slen << HIFN_BASE_CMD_SRCLEN_S) & HIFN_BASE_CMD_SRCLEN_M) |
            ((dlen << HIFN_BASE_CMD_DSTLEN_S) & HIFN_BASE_CMD_DSTLEN_M));

        return sizeof(struct hifn_base_command);
}

static int hifn_setup_crypto_command(struct hifn_device *dev,
                u8 *buf, unsigned dlen, unsigned slen,
                u8 *key, int keylen, u8 *iv, int ivsize, u16 mode)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        struct hifn_crypt_command *cry_cmd;
        u8 *buf_pos = buf;
        u16 cmd_len;

        cry_cmd = (struct hifn_crypt_command *)buf_pos;

        cry_cmd->source_count = __cpu_to_le16(dlen & 0xffff);
        dlen >>= 16;
        cry_cmd->masks = __cpu_to_le16(mode |
                        ((dlen << HIFN_CRYPT_CMD_SRCLEN_S) &
                         HIFN_CRYPT_CMD_SRCLEN_M));
        cry_cmd->header_skip = 0;
        cry_cmd->reserved = 0;

        buf_pos += sizeof(struct hifn_crypt_command);

        dma->cmdu++;
        if (dma->cmdu > 1) {
                dev->dmareg |= HIFN_DMAIER_C_WAIT;
                hifn_write_1(dev, HIFN_1_DMA_IER, dev->dmareg);
        }

        if (keylen) {
                memcpy(buf_pos, key, keylen);
                buf_pos += keylen;
        }
        if (ivsize) {
                memcpy(buf_pos, iv, ivsize);
                buf_pos += ivsize;
        }

        cmd_len = buf_pos - buf;

        return cmd_len;
}

static int hifn_setup_cmd_desc(struct hifn_device *dev,
                struct hifn_context *ctx, struct hifn_request_context *rctx,
                void *priv, unsigned int nbytes)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        int cmd_len, sa_idx;
        u8 *buf, *buf_pos;
        u16 mask;

        sa_idx = dma->cmdi;
        buf_pos = buf = dma->command_bufs[dma->cmdi];

        mask = 0;
        switch (rctx->op) {
        case ACRYPTO_OP_DECRYPT:
                mask = HIFN_BASE_CMD_CRYPT | HIFN_BASE_CMD_DECODE;
                break;
        case ACRYPTO_OP_ENCRYPT:
                mask = HIFN_BASE_CMD_CRYPT;
                break;
        case ACRYPTO_OP_HMAC:
                mask = HIFN_BASE_CMD_MAC;
                break;
        default:
                goto err_out;
        }

        buf_pos += hifn_setup_base_command(dev, buf_pos, nbytes,
                        nbytes, mask, dev->snum);

        if (rctx->op == ACRYPTO_OP_ENCRYPT || rctx->op == ACRYPTO_OP_DECRYPT) {
                u16 md = 0;

                if (ctx->keysize)
                        md |= HIFN_CRYPT_CMD_NEW_KEY;
                if (rctx->iv && rctx->mode != ACRYPTO_MODE_ECB)
                        md |= HIFN_CRYPT_CMD_NEW_IV;

                switch (rctx->mode) {
                case ACRYPTO_MODE_ECB:
                        md |= HIFN_CRYPT_CMD_MODE_ECB;
                        break;
                case ACRYPTO_MODE_CBC:
                        md |= HIFN_CRYPT_CMD_MODE_CBC;
                        break;
                case ACRYPTO_MODE_CFB:
                        md |= HIFN_CRYPT_CMD_MODE_CFB;
                        break;
                case ACRYPTO_MODE_OFB:
                        md |= HIFN_CRYPT_CMD_MODE_OFB;
                        break;
                default:
                        goto err_out;
                }

                switch (rctx->type) {
                case ACRYPTO_TYPE_AES_128:
                        if (ctx->keysize != 16)
                                goto err_out;
                        md |= HIFN_CRYPT_CMD_KSZ_128 |
                                HIFN_CRYPT_CMD_ALG_AES;
                        break;
                case ACRYPTO_TYPE_AES_192:
                        if (ctx->keysize != 24)
                                goto err_out;
                        md |= HIFN_CRYPT_CMD_KSZ_192 |
                                HIFN_CRYPT_CMD_ALG_AES;
                        break;
                case ACRYPTO_TYPE_AES_256:
                        if (ctx->keysize != 32)
                                goto err_out;
                        md |= HIFN_CRYPT_CMD_KSZ_256 |
                                HIFN_CRYPT_CMD_ALG_AES;
                        break;
                case ACRYPTO_TYPE_3DES:
                        if (ctx->keysize != 24)
                                goto err_out;
                        md |= HIFN_CRYPT_CMD_ALG_3DES;
                        break;
                case ACRYPTO_TYPE_DES:
                        if (ctx->keysize != 8)
                                goto err_out;
                        md |= HIFN_CRYPT_CMD_ALG_DES;
                        break;
                default:
                        goto err_out;
                }

                buf_pos += hifn_setup_crypto_command(dev, buf_pos,
                                nbytes, nbytes, ctx->key, ctx->keysize,
                                rctx->iv, rctx->ivsize, md);
        }

        dev->sa[sa_idx] = priv;
        dev->started++;

        cmd_len = buf_pos - buf;
        dma->cmdr[dma->cmdi].l = __cpu_to_le32(cmd_len | HIFN_D_VALID |
                        HIFN_D_LAST | HIFN_D_MASKDONEIRQ);

        if (++dma->cmdi == HIFN_D_CMD_RSIZE) {
                dma->cmdr[dma->cmdi].l = __cpu_to_le32(
                        HIFN_D_VALID | HIFN_D_LAST |
                        HIFN_D_MASKDONEIRQ | HIFN_D_JUMP);
                dma->cmdi = 0;
        } else {
                dma->cmdr[dma->cmdi - 1].l |= __cpu_to_le32(HIFN_D_VALID);
        }

        if (!(dev->flags & HIFN_FLAG_CMD_BUSY)) {
                hifn_write_1(dev, HIFN_1_DMA_CSR, HIFN_DMACSR_C_CTRL_ENA);
                dev->flags |= HIFN_FLAG_CMD_BUSY;
        }
        return 0;

err_out:
        return -EINVAL;
}

static int hifn_setup_src_desc(struct hifn_device *dev, struct page *page,
                unsigned int offset, unsigned int size, int last)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        int idx;
        dma_addr_t addr;

        addr = pci_map_page(dev->pdev, page, offset, size, PCI_DMA_TODEVICE);

        idx = dma->srci;

        dma->srcr[idx].p = __cpu_to_le32(addr);
        dma->srcr[idx].l = __cpu_to_le32(size | HIFN_D_VALID |
                        HIFN_D_MASKDONEIRQ | (last ? HIFN_D_LAST : 0));

        if (++idx == HIFN_D_SRC_RSIZE) {
                dma->srcr[idx].l = __cpu_to_le32(HIFN_D_VALID |
                                HIFN_D_JUMP | HIFN_D_MASKDONEIRQ |
                                (last ? HIFN_D_LAST : 0));
                idx = 0;
        }

        dma->srci = idx;
        dma->srcu++;

        if (!(dev->flags & HIFN_FLAG_SRC_BUSY)) {
                hifn_write_1(dev, HIFN_1_DMA_CSR, HIFN_DMACSR_S_CTRL_ENA);
                dev->flags |= HIFN_FLAG_SRC_BUSY;
        }

        return size;
}

static void hifn_setup_res_desc(struct hifn_device *dev)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;

        dma->resr[dma->resi].l = __cpu_to_le32(HIFN_USED_RESULT |
                        HIFN_D_VALID | HIFN_D_LAST);
        /*
         * dma->resr[dma->resi].l = __cpu_to_le32(HIFN_MAX_RESULT | HIFN_D_VALID |
         *                                      HIFN_D_LAST);
         */

        if (++dma->resi == HIFN_D_RES_RSIZE) {
                dma->resr[HIFN_D_RES_RSIZE].l = __cpu_to_le32(HIFN_D_VALID |
                                HIFN_D_JUMP | HIFN_D_MASKDONEIRQ | HIFN_D_LAST);
                dma->resi = 0;
        }

        dma->resu++;

        if (!(dev->flags & HIFN_FLAG_RES_BUSY)) {
                hifn_write_1(dev, HIFN_1_DMA_CSR, HIFN_DMACSR_R_CTRL_ENA);
                dev->flags |= HIFN_FLAG_RES_BUSY;
        }
}

static void hifn_setup_dst_desc(struct hifn_device *dev, struct page *page,
                unsigned offset, unsigned size, int last)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        int idx;
        dma_addr_t addr;

        addr = pci_map_page(dev->pdev, page, offset, size, PCI_DMA_FROMDEVICE);

        idx = dma->dsti;
        dma->dstr[idx].p = __cpu_to_le32(addr);
        dma->dstr[idx].l = __cpu_to_le32(size | HIFN_D_VALID |
                        HIFN_D_MASKDONEIRQ | (last ? HIFN_D_LAST : 0));

        if (++idx == HIFN_D_DST_RSIZE) {
                dma->dstr[idx].l = __cpu_to_le32(HIFN_D_VALID |
                                HIFN_D_JUMP | HIFN_D_MASKDONEIRQ |
                                (last ? HIFN_D_LAST : 0));
                idx = 0;
        }
        dma->dsti = idx;
        dma->dstu++;

        if (!(dev->flags & HIFN_FLAG_DST_BUSY)) {
                hifn_write_1(dev, HIFN_1_DMA_CSR, HIFN_DMACSR_D_CTRL_ENA);
                dev->flags |= HIFN_FLAG_DST_BUSY;
        }
}

static int hifn_setup_dma(struct hifn_device *dev,
                struct hifn_context *ctx, struct hifn_request_context *rctx,
                struct scatterlist *src, struct scatterlist *dst,
                unsigned int nbytes, void *priv)
{
        struct scatterlist *t;
        struct page *spage, *dpage;
        unsigned int soff, doff;
        unsigned int n, len;

        n = nbytes;
        while (n) {
                spage = sg_page(src);
                soff = src->offset;
                len = min(src->length, n);

                hifn_setup_src_desc(dev, spage, soff, len, n - len == 0);

                src++;
                n -= len;
        }

        t = &rctx->walk.cache[0];
        n = nbytes;
        while (n) {
                if (t->length && rctx->walk.flags & ASYNC_FLAGS_MISALIGNED) {
                        BUG_ON(!sg_page(t));
                        dpage = sg_page(t);
                        doff = 0;
                        len = t->length;
                } else {
                        BUG_ON(!sg_page(dst));
                        dpage = sg_page(dst);
                        doff = dst->offset;
                        len = dst->length;
                }
                len = min(len, n);

                hifn_setup_dst_desc(dev, dpage, doff, len, n - len == 0);

                dst++;
                t++;
                n -= len;
        }

        hifn_setup_cmd_desc(dev, ctx, rctx, priv, nbytes);
        hifn_setup_res_desc(dev);
        return 0;
}

static int hifn_cipher_walk_init(struct hifn_cipher_walk *w,
                int num, gfp_t gfp_flags)
{
        int i;

        num = min(ASYNC_SCATTERLIST_CACHE, num);
        sg_init_table(w->cache, num);

        w->num = 0;
        for (i = 0; i < num; ++i) {
                struct page *page = alloc_page(gfp_flags);
                struct scatterlist *s;

                if (!page)
                        break;

                s = &w->cache[i];

                sg_set_page(s, page, PAGE_SIZE, 0);
                w->num++;
        }

        return i;
}

static void hifn_cipher_walk_exit(struct hifn_cipher_walk *w)
{
        int i;

        for (i = 0; i < w->num; ++i) {
                struct scatterlist *s = &w->cache[i];

                __free_page(sg_page(s));

                s->length = 0;
        }

        w->num = 0;
}

static int skcipher_add(unsigned int *drestp, struct scatterlist *dst,
                unsigned int size, unsigned int *nbytesp)
{
        unsigned int copy, drest = *drestp, nbytes = *nbytesp;
        int idx = 0;

        if (drest < size || size > nbytes)
                return -EINVAL;

        while (size) {
                copy = min3(drest, size, dst->length);

                size -= copy;
                drest -= copy;
                nbytes -= copy;

                pr_debug("%s: copy: %u, size: %u, drest: %u, nbytes: %u.\n",
                         __func__, copy, size, drest, nbytes);

                dst++;
                idx++;
        }

        *nbytesp = nbytes;
        *drestp = drest;

        return idx;
}

static int hifn_cipher_walk(struct skcipher_request *req,
                struct hifn_cipher_walk *w)
{
        struct scatterlist *dst, *t;
        unsigned int nbytes = req->cryptlen, offset, copy, diff;
        int idx, tidx, err;

        tidx = idx = 0;
        offset = 0;
        while (nbytes) {
                if (idx >= w->num && (w->flags & ASYNC_FLAGS_MISALIGNED))
                        return -EINVAL;

                dst = &req->dst[idx];

                pr_debug("\n%s: dlen: %u, doff: %u, offset: %u, nbytes: %u.\n",
                         __func__, dst->length, dst->offset, offset, nbytes);

                if (!IS_ALIGNED(dst->offset, HIFN_D_DST_DALIGN) ||
                    !IS_ALIGNED(dst->length, HIFN_D_DST_DALIGN) ||
                    offset) {
                        unsigned slen = min(dst->length - offset, nbytes);
                        unsigned dlen = PAGE_SIZE;

                        t = &w->cache[idx];

                        err = skcipher_add(&dlen, dst, slen, &nbytes);
                        if (err < 0)
                                return err;

                        idx += err;

                        copy = slen & ~(HIFN_D_DST_DALIGN - 1);
                        diff = slen & (HIFN_D_DST_DALIGN - 1);

                        if (dlen < nbytes) {
                                /*
                                 * Destination page does not have enough space
                                 * to put there additional blocksized chunk,
                                 * so we mark that page as containing only
                                 * blocksize aligned chunks:
                                 *      t->length = (slen & ~(HIFN_D_DST_DALIGN - 1));
                                 * and increase number of bytes to be processed
                                 * in next chunk:
                                 *      nbytes += diff;
                                 */
                                nbytes += diff;

                                /*
                                 * Temporary of course...
                                 * Kick author if you will catch this one.
                                 */
                                pr_err("%s: dlen: %u, nbytes: %u, slen: %u, offset: %u.\n",
                                       __func__, dlen, nbytes, slen, offset);
                                pr_err("%s: please contact author to fix this "
                                       "issue, generally you should not catch "
                                       "this path under any condition but who "
                                       "knows how did you use crypto code.\n"
                                       "Thank you.\n",  __func__);
                                BUG();
                        } else {
                                copy += diff + nbytes;

                                dst = &req->dst[idx];

                                err = skcipher_add(&dlen, dst, nbytes, &nbytes);
                                if (err < 0)
                                        return err;

                                idx += err;
                        }

                        t->length = copy;
                        t->offset = offset;
                } else {
                        nbytes -= min(dst->length, nbytes);
                        idx++;
                }

                tidx++;
        }

        return tidx;
}

static int hifn_setup_session(struct skcipher_request *req)
{
        struct hifn_context *ctx = crypto_tfm_ctx(req->base.tfm);
        struct hifn_request_context *rctx = skcipher_request_ctx(req);
        struct hifn_device *dev = ctx->dev;
        unsigned long dlen, flags;
        unsigned int nbytes = req->cryptlen, idx = 0;
        int err = -EINVAL, sg_num;
        struct scatterlist *dst;

        if (rctx->iv && !rctx->ivsize && rctx->mode != ACRYPTO_MODE_ECB)
                goto err_out_exit;

        rctx->walk.flags = 0;

        while (nbytes) {
                dst = &req->dst[idx];
                dlen = min(dst->length, nbytes);

                if (!IS_ALIGNED(dst->offset, HIFN_D_DST_DALIGN) ||
                    !IS_ALIGNED(dlen, HIFN_D_DST_DALIGN))
                        rctx->walk.flags |= ASYNC_FLAGS_MISALIGNED;

                nbytes -= dlen;
                idx++;
        }

        if (rctx->walk.flags & ASYNC_FLAGS_MISALIGNED) {
                err = hifn_cipher_walk_init(&rctx->walk, idx, GFP_ATOMIC);
                if (err < 0)
                        return err;
        }

        sg_num = hifn_cipher_walk(req, &rctx->walk);
        if (sg_num < 0) {
                err = sg_num;
                goto err_out_exit;
        }

        spin_lock_irqsave(&dev->lock, flags);
        if (dev->started + sg_num > HIFN_QUEUE_LENGTH) {
                err = -EAGAIN;
                goto err_out;
        }

        err = hifn_setup_dma(dev, ctx, rctx, req->src, req->dst, req->cryptlen, req);
        if (err)
                goto err_out;

        dev->snum++;

        dev->active = HIFN_DEFAULT_ACTIVE_NUM;
        spin_unlock_irqrestore(&dev->lock, flags);

        return 0;

err_out:
        spin_unlock_irqrestore(&dev->lock, flags);
err_out_exit:
        if (err) {
                dev_info(&dev->pdev->dev, "iv: %p [%d], key: %p [%d], mode: %u, op: %u, "
                         "type: %u, err: %d.\n",
                         rctx->iv, rctx->ivsize,
                         ctx->key, ctx->keysize,
                         rctx->mode, rctx->op, rctx->type, err);
        }

        return err;
}

static int hifn_start_device(struct hifn_device *dev)
{
        int err;

        dev->started = dev->active = 0;
        hifn_reset_dma(dev, 1);

        err = hifn_enable_crypto(dev);
        if (err)
                return err;

        hifn_reset_puc(dev);

        hifn_init_dma(dev);

        hifn_init_registers(dev);

        hifn_init_pubrng(dev);

        return 0;
}

static int skcipher_get(void *saddr, unsigned int *srestp, unsigned int offset,
                struct scatterlist *dst, unsigned int size, unsigned int *nbytesp)
{
        unsigned int srest = *srestp, nbytes = *nbytesp, copy;
        void *daddr;
        int idx = 0;

        if (srest < size || size > nbytes)
                return -EINVAL;

        while (size) {
                copy = min3(srest, dst->length, size);

                daddr = kmap_atomic(sg_page(dst));
                memcpy(daddr + dst->offset + offset, saddr, copy);
                kunmap_atomic(daddr);

                nbytes -= copy;
                size -= copy;
                srest -= copy;
                saddr += copy;
                offset = 0;

                pr_debug("%s: copy: %u, size: %u, srest: %u, nbytes: %u.\n",
                         __func__, copy, size, srest, nbytes);

                dst++;
                idx++;
        }

        *nbytesp = nbytes;
        *srestp = srest;

        return idx;
}

static inline void hifn_complete_sa(struct hifn_device *dev, int i)
{
        unsigned long flags;

        spin_lock_irqsave(&dev->lock, flags);
        dev->sa[i] = NULL;
        dev->started--;
        if (dev->started < 0)
                dev_info(&dev->pdev->dev, "%s: started: %d.\n", __func__,
                         dev->started);
        spin_unlock_irqrestore(&dev->lock, flags);
        BUG_ON(dev->started < 0);
}

static void hifn_process_ready(struct skcipher_request *req, int error)
{
        struct hifn_request_context *rctx = skcipher_request_ctx(req);

        if (rctx->walk.flags & ASYNC_FLAGS_MISALIGNED) {
                unsigned int nbytes = req->cryptlen;
                int idx = 0, err;
                struct scatterlist *dst, *t;
                void *saddr;

                while (nbytes) {
                        t = &rctx->walk.cache[idx];
                        dst = &req->dst[idx];

                        pr_debug("\n%s: sg_page(t): %p, t->length: %u, "
                                "sg_page(dst): %p, dst->length: %u, "
                                "nbytes: %u.\n",
                                __func__, sg_page(t), t->length,
                                sg_page(dst), dst->length, nbytes);

                        if (!t->length) {
                                nbytes -= min(dst->length, nbytes);
                                idx++;
                                continue;
                        }

                        saddr = kmap_atomic(sg_page(t));

                        err = skcipher_get(saddr, &t->length, t->offset,
                                        dst, nbytes, &nbytes);
                        if (err < 0) {
                                kunmap_atomic(saddr);
                                break;
                        }

                        idx += err;
                        kunmap_atomic(saddr);
                }

                hifn_cipher_walk_exit(&rctx->walk);
        }

        req->base.complete(&req->base, error);
}

static void hifn_clear_rings(struct hifn_device *dev, int error)
{
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        int i, u;

        dev_dbg(&dev->pdev->dev, "ring cleanup 1: i: %d.%d.%d.%d, u: %d.%d.%d.%d, "
                        "k: %d.%d.%d.%d.\n",
                        dma->cmdi, dma->srci, dma->dsti, dma->resi,
                        dma->cmdu, dma->srcu, dma->dstu, dma->resu,
                        dma->cmdk, dma->srck, dma->dstk, dma->resk);

        i = dma->resk; u = dma->resu;
        while (u != 0) {
                if (dma->resr[i].l & __cpu_to_le32(HIFN_D_VALID))
                        break;

                if (dev->sa[i]) {
                        dev->success++;
                        dev->reset = 0;
                        hifn_process_ready(dev->sa[i], error);
                        hifn_complete_sa(dev, i);
                }

                if (++i == HIFN_D_RES_RSIZE)
                        i = 0;
                u--;
        }
        dma->resk = i; dma->resu = u;

        i = dma->srck; u = dma->srcu;
        while (u != 0) {
                if (dma->srcr[i].l & __cpu_to_le32(HIFN_D_VALID))
                        break;
                if (++i == HIFN_D_SRC_RSIZE)
                        i = 0;
                u--;
        }
        dma->srck = i; dma->srcu = u;

        i = dma->cmdk; u = dma->cmdu;
        while (u != 0) {
                if (dma->cmdr[i].l & __cpu_to_le32(HIFN_D_VALID))
                        break;
                if (++i == HIFN_D_CMD_RSIZE)
                        i = 0;
                u--;
        }
        dma->cmdk = i; dma->cmdu = u;

        i = dma->dstk; u = dma->dstu;
        while (u != 0) {
                if (dma->dstr[i].l & __cpu_to_le32(HIFN_D_VALID))
                        break;
                if (++i == HIFN_D_DST_RSIZE)
                        i = 0;
                u--;
        }
        dma->dstk = i; dma->dstu = u;

        dev_dbg(&dev->pdev->dev, "ring cleanup 2: i: %d.%d.%d.%d, u: %d.%d.%d.%d, "
                        "k: %d.%d.%d.%d.\n",
                        dma->cmdi, dma->srci, dma->dsti, dma->resi,
                        dma->cmdu, dma->srcu, dma->dstu, dma->resu,
                        dma->cmdk, dma->srck, dma->dstk, dma->resk);
}

static void hifn_work(struct work_struct *work)
{
        struct delayed_work *dw = to_delayed_work(work);
        struct hifn_device *dev = container_of(dw, struct hifn_device, work);
        unsigned long flags;
        int reset = 0;
        u32 r = 0;

        spin_lock_irqsave(&dev->lock, flags);
        if (dev->active == 0) {
                struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;

                if (dma->cmdu == 0 && (dev->flags & HIFN_FLAG_CMD_BUSY)) {
                        dev->flags &= ~HIFN_FLAG_CMD_BUSY;
                        r |= HIFN_DMACSR_C_CTRL_DIS;
                }
                if (dma->srcu == 0 && (dev->flags & HIFN_FLAG_SRC_BUSY)) {
                        dev->flags &= ~HIFN_FLAG_SRC_BUSY;
                        r |= HIFN_DMACSR_S_CTRL_DIS;
                }
                if (dma->dstu == 0 && (dev->flags & HIFN_FLAG_DST_BUSY)) {
                        dev->flags &= ~HIFN_FLAG_DST_BUSY;
                        r |= HIFN_DMACSR_D_CTRL_DIS;
                }
                if (dma->resu == 0 && (dev->flags & HIFN_FLAG_RES_BUSY)) {
                        dev->flags &= ~HIFN_FLAG_RES_BUSY;
                        r |= HIFN_DMACSR_R_CTRL_DIS;
                }
                if (r)
                        hifn_write_1(dev, HIFN_1_DMA_CSR, r);
        } else
                dev->active--;

        if ((dev->prev_success == dev->success) && dev->started)
                reset = 1;
        dev->prev_success = dev->success;
        spin_unlock_irqrestore(&dev->lock, flags);

        if (reset) {
                if (++dev->reset >= 5) {
                        int i;
                        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;

                        dev_info(&dev->pdev->dev,
                                 "r: %08x, active: %d, started: %d, "
                                 "success: %lu: qlen: %u/%u, reset: %d.\n",
                                 r, dev->active, dev->started,
                                 dev->success, dev->queue.qlen, dev->queue.max_qlen,
                                 reset);

                        dev_info(&dev->pdev->dev, "%s: res: ", __func__);
                        for (i = 0; i < HIFN_D_RES_RSIZE; ++i) {
                                pr_info("%x.%p ", dma->resr[i].l, dev->sa[i]);
                                if (dev->sa[i]) {
                                        hifn_process_ready(dev->sa[i], -ENODEV);
                                        hifn_complete_sa(dev, i);
                                }
                        }
                        pr_info("\n");

                        hifn_reset_dma(dev, 1);
                        hifn_stop_device(dev);
                        hifn_start_device(dev);
                        dev->reset = 0;
                }

                tasklet_schedule(&dev->tasklet);
        }

        schedule_delayed_work(&dev->work, HZ);
}

static irqreturn_t hifn_interrupt(int irq, void *data)
{
        struct hifn_device *dev = (struct hifn_device *)data;
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        u32 dmacsr, restart;

        dmacsr = hifn_read_1(dev, HIFN_1_DMA_CSR);

        dev_dbg(&dev->pdev->dev, "1 dmacsr: %08x, dmareg: %08x, res: %08x [%d], "
                        "i: %d.%d.%d.%d, u: %d.%d.%d.%d.\n",
                dmacsr, dev->dmareg, dmacsr & dev->dmareg, dma->cmdi,
                dma->cmdi, dma->srci, dma->dsti, dma->resi,
                dma->cmdu, dma->srcu, dma->dstu, dma->resu);

        if ((dmacsr & dev->dmareg) == 0)
                return IRQ_NONE;

        hifn_write_1(dev, HIFN_1_DMA_CSR, dmacsr & dev->dmareg);

        if (dmacsr & HIFN_DMACSR_ENGINE)
                hifn_write_0(dev, HIFN_0_PUISR, hifn_read_0(dev, HIFN_0_PUISR));
        if (dmacsr & HIFN_DMACSR_PUBDONE)
                hifn_write_1(dev, HIFN_1_PUB_STATUS,
                        hifn_read_1(dev, HIFN_1_PUB_STATUS) | HIFN_PUBSTS_DONE);

        restart = dmacsr & (HIFN_DMACSR_R_OVER | HIFN_DMACSR_D_OVER);
        if (restart) {
                u32 puisr = hifn_read_0(dev, HIFN_0_PUISR);

                dev_warn(&dev->pdev->dev, "overflow: r: %d, d: %d, puisr: %08x, d: %u.\n",
                         !!(dmacsr & HIFN_DMACSR_R_OVER),
                         !!(dmacsr & HIFN_DMACSR_D_OVER),
                        puisr, !!(puisr & HIFN_PUISR_DSTOVER));
                if (!!(puisr & HIFN_PUISR_DSTOVER))
                        hifn_write_0(dev, HIFN_0_PUISR, HIFN_PUISR_DSTOVER);
                hifn_write_1(dev, HIFN_1_DMA_CSR, dmacsr & (HIFN_DMACSR_R_OVER |
                                        HIFN_DMACSR_D_OVER));
        }

        restart = dmacsr & (HIFN_DMACSR_C_ABORT | HIFN_DMACSR_S_ABORT |
                        HIFN_DMACSR_D_ABORT | HIFN_DMACSR_R_ABORT);
        if (restart) {
                dev_warn(&dev->pdev->dev, "abort: c: %d, s: %d, d: %d, r: %d.\n",
                         !!(dmacsr & HIFN_DMACSR_C_ABORT),
                         !!(dmacsr & HIFN_DMACSR_S_ABORT),
                         !!(dmacsr & HIFN_DMACSR_D_ABORT),
                         !!(dmacsr & HIFN_DMACSR_R_ABORT));
                hifn_reset_dma(dev, 1);
                hifn_init_dma(dev);
                hifn_init_registers(dev);
        }

        if ((dmacsr & HIFN_DMACSR_C_WAIT) && (dma->cmdu == 0)) {
                dev_dbg(&dev->pdev->dev, "wait on command.\n");
                dev->dmareg &= ~(HIFN_DMAIER_C_WAIT);
                hifn_write_1(dev, HIFN_1_DMA_IER, dev->dmareg);
        }

        tasklet_schedule(&dev->tasklet);

        return IRQ_HANDLED;
}

static void hifn_flush(struct hifn_device *dev)
{
        unsigned long flags;
        struct crypto_async_request *async_req;
        struct skcipher_request *req;
        struct hifn_dma *dma = (struct hifn_dma *)dev->desc_virt;
        int i;

        for (i = 0; i < HIFN_D_RES_RSIZE; ++i) {
                struct hifn_desc *d = &dma->resr[i];

                if (dev->sa[i]) {
                        hifn_process_ready(dev->sa[i],
                                (d->l & __cpu_to_le32(HIFN_D_VALID)) ? -ENODEV : 0);
                        hifn_complete_sa(dev, i);
                }
        }

        spin_lock_irqsave(&dev->lock, flags);
        while ((async_req = crypto_dequeue_request(&dev->queue))) {
                req = skcipher_request_cast(async_req);
                spin_unlock_irqrestore(&dev->lock, flags);

                hifn_process_ready(req, -ENODEV);

                spin_lock_irqsave(&dev->lock, flags);
        }
        spin_unlock_irqrestore(&dev->lock, flags);
}

static int hifn_setkey(struct crypto_skcipher *cipher, const u8 *key,
                unsigned int len)
{
        struct hifn_context *ctx = crypto_skcipher_ctx(cipher);
        struct hifn_device *dev = ctx->dev;
        int err;

        err = verify_skcipher_des_key(cipher, key);
        if (err)
                return err;

        dev->flags &= ~HIFN_FLAG_OLD_KEY;

        memcpy(ctx->key, key, len);
        ctx->keysize = len;

        return 0;
}

static int hifn_des3_setkey(struct crypto_skcipher *cipher, const u8 *key,
                            unsigned int len)
{
        struct hifn_context *ctx = crypto_skcipher_ctx(cipher);
        struct hifn_device *dev = ctx->dev;
        int err;

        err = verify_skcipher_des3_key(cipher, key);
        if (err)
                return err;

        dev->flags &= ~HIFN_FLAG_OLD_KEY;

        memcpy(ctx->key, key, len);
        ctx->keysize = len;

        return 0;
}

static int hifn_handle_req(struct skcipher_request *req)
{
        struct hifn_context *ctx = crypto_tfm_ctx(req->base.tfm);
        struct hifn_device *dev = ctx->dev;
        int err = -EAGAIN;

        if (dev->started + DIV_ROUND_UP(req->cryptlen, PAGE_SIZE) <= HIFN_QUEUE_LENGTH)
                err = hifn_setup_session(req);

        if (err == -EAGAIN) {
                unsigned long flags;

                spin_lock_irqsave(&dev->lock, flags);
                err = crypto_enqueue_request(&dev->queue, &req->base);
                spin_unlock_irqrestore(&dev->lock, flags);
        }

        return err;
}

static int hifn_setup_crypto_req(struct skcipher_request *req, u8 op,
                u8 type, u8 mode)
{

        struct hifn_context *ctx = crypto_tfm_ctx(req->base.tfm);
        struct hifn_request_context *rctx = skcipher_request_ctx(req);
        unsigned ivsize;

        ivsize = crypto_skcipher_ivsize(crypto_skcipher_reqtfm(req));

        if (req->iv && mode != ACRYPTO_MODE_ECB) {
                if (type == ACRYPTO_TYPE_AES_128)
                        ivsize = HIFN_AES_IV_LENGTH;
                else if (type == ACRYPTO_TYPE_DES)
                        ivsize = HIFN_DES_KEY_LENGTH;
                else if (type == ACRYPTO_TYPE_3DES)
                        ivsize = HIFN_3DES_KEY_LENGTH;
        }

        if (ctx->keysize != 16 && type == ACRYPTO_TYPE_AES_128) {
                if (ctx->keysize == 24)
                        type = ACRYPTO_TYPE_AES_192;
                else if (ctx->keysize == 32)
                        type = ACRYPTO_TYPE_AES_256;
        }

        rctx->op = op;
        rctx->mode = mode;
        rctx->type = type;
        rctx->iv = req->iv;
        rctx->ivsize = ivsize;

        /*
         * HEAVY TODO: needs to kick Herbert XU to write documentation.
         * HEAVY TODO: needs to kick Herbert XU to write documentation.
         * HEAVY TODO: needs to kick Herbert XU to write documentation.
         */

        return hifn_handle_req(req);
}

static int hifn_process_queue(struct hifn_device *dev)
{
        struct crypto_async_request *async_req, *backlog;
        struct skcipher_request *req;
        unsigned long flags;
        int err = 0;

        while (dev->started < HIFN_QUEUE_LENGTH) {
                spin_lock_irqsave(&dev->lock, flags);
                backlog = crypto_get_backlog(&dev->queue);
                async_req = crypto_dequeue_request(&dev->queue);
                spin_unlock_irqrestore(&dev->lock, flags);

                if (!async_req)
                        break;

                if (backlog)
                        backlog->complete(backlog, -EINPROGRESS);

                req = skcipher_request_cast(async_req);

                err = hifn_handle_req(req);
                if (err)
                        break;
        }

        return err;
}

static int hifn_setup_crypto(struct skcipher_request *req, u8 op,
                u8 type, u8 mode)
{
        int err;
        struct hifn_context *ctx = crypto_tfm_ctx(req->base.tfm);
        struct hifn_device *dev = ctx->dev;

        err = hifn_setup_crypto_req(req, op, type, mode);
        if (err)
                return err;

        if (dev->started < HIFN_QUEUE_LENGTH && dev->queue.qlen)
                hifn_process_queue(dev);

        return -EINPROGRESS;
}

/*
 * AES ecryption functions.
 */
static inline int hifn_encrypt_aes_ecb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_ECB);
}
static inline int hifn_encrypt_aes_cbc(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_CBC);
}
static inline int hifn_encrypt_aes_cfb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_CFB);
}
static inline int hifn_encrypt_aes_ofb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_OFB);
}

/*
 * AES decryption functions.
 */
static inline int hifn_decrypt_aes_ecb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_ECB);
}
static inline int hifn_decrypt_aes_cbc(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_CBC);
}
static inline int hifn_decrypt_aes_cfb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_CFB);
}
static inline int hifn_decrypt_aes_ofb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_AES_128, ACRYPTO_MODE_OFB);
}

/*
 * DES ecryption functions.
 */
static inline int hifn_encrypt_des_ecb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_ECB);
}
static inline int hifn_encrypt_des_cbc(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_CBC);
}
static inline int hifn_encrypt_des_cfb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_CFB);
}
static inline int hifn_encrypt_des_ofb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_OFB);
}

/*
 * DES decryption functions.
 */
static inline int hifn_decrypt_des_ecb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_ECB);
}
static inline int hifn_decrypt_des_cbc(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_CBC);
}
static inline int hifn_decrypt_des_cfb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_CFB);
}
static inline int hifn_decrypt_des_ofb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_DES, ACRYPTO_MODE_OFB);
}

/*
 * 3DES ecryption functions.
 */
static inline int hifn_encrypt_3des_ecb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_ECB);
}
static inline int hifn_encrypt_3des_cbc(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_CBC);
}
static inline int hifn_encrypt_3des_cfb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_CFB);
}
static inline int hifn_encrypt_3des_ofb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_ENCRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_OFB);
}

/* 3DES decryption functions. */
static inline int hifn_decrypt_3des_ecb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_ECB);
}
static inline int hifn_decrypt_3des_cbc(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_CBC);
}
static inline int hifn_decrypt_3des_cfb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_CFB);
}
static inline int hifn_decrypt_3des_ofb(struct skcipher_request *req)
{
        return hifn_setup_crypto(req, ACRYPTO_OP_DECRYPT,
                        ACRYPTO_TYPE_3DES, ACRYPTO_MODE_OFB);
}

struct hifn_alg_template {
        char name[CRYPTO_MAX_ALG_NAME];
        char drv_name[CRYPTO_MAX_ALG_NAME];
        unsigned int bsize;
        struct skcipher_alg skcipher;
};

static const struct hifn_alg_template hifn_alg_templates[] = {
        /*
         * 3DES ECB, CBC, CFB and OFB modes.
         */
        {
                .name = "cfb(des3_ede)", .drv_name = "cfb-3des", .bsize = 8,
                .skcipher = {
                        .min_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .setkey         =       hifn_des3_setkey,
                        .encrypt        =       hifn_encrypt_3des_cfb,
                        .decrypt        =       hifn_decrypt_3des_cfb,
                },
        },
        {
                .name = "ofb(des3_ede)", .drv_name = "ofb-3des", .bsize = 8,
                .skcipher = {
                        .min_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .setkey         =       hifn_des3_setkey,
                        .encrypt        =       hifn_encrypt_3des_ofb,
                        .decrypt        =       hifn_decrypt_3des_ofb,
                },
        },
        {
                .name = "cbc(des3_ede)", .drv_name = "cbc-3des", .bsize = 8,
                .skcipher = {
                        .ivsize         =       HIFN_IV_LENGTH,
                        .min_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .setkey         =       hifn_des3_setkey,
                        .encrypt        =       hifn_encrypt_3des_cbc,
                        .decrypt        =       hifn_decrypt_3des_cbc,
                },
        },
        {
                .name = "ecb(des3_ede)", .drv_name = "ecb-3des", .bsize = 8,
                .skcipher = {
                        .min_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_3DES_KEY_LENGTH,
                        .setkey         =       hifn_des3_setkey,
                        .encrypt        =       hifn_encrypt_3des_ecb,
                        .decrypt        =       hifn_decrypt_3des_ecb,
                },
        },

        /*
         * DES ECB, CBC, CFB and OFB modes.
         */
        {
                .name = "cfb(des)", .drv_name = "cfb-des", .bsize = 8,
                .skcipher = {
                        .min_keysize    =       HIFN_DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_DES_KEY_LENGTH,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_des_cfb,
                        .decrypt        =       hifn_decrypt_des_cfb,
                },
        },
        {
                .name = "ofb(des)", .drv_name = "ofb-des", .bsize = 8,
                .skcipher = {
                        .min_keysize    =       HIFN_DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_DES_KEY_LENGTH,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_des_ofb,
                        .decrypt        =       hifn_decrypt_des_ofb,
                },
        },
        {
                .name = "cbc(des)", .drv_name = "cbc-des", .bsize = 8,
                .skcipher = {
                        .ivsize         =       HIFN_IV_LENGTH,
                        .min_keysize    =       HIFN_DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_DES_KEY_LENGTH,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_des_cbc,
                        .decrypt        =       hifn_decrypt_des_cbc,
                },
        },
        {
                .name = "ecb(des)", .drv_name = "ecb-des", .bsize = 8,
                .skcipher = {
                        .min_keysize    =       HIFN_DES_KEY_LENGTH,
                        .max_keysize    =       HIFN_DES_KEY_LENGTH,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_des_ecb,
                        .decrypt        =       hifn_decrypt_des_ecb,
                },
        },

        /*
         * AES ECB, CBC, CFB and OFB modes.
         */
        {
                .name = "ecb(aes)", .drv_name = "ecb-aes", .bsize = 16,
                .skcipher = {
                        .min_keysize    =       AES_MIN_KEY_SIZE,
                        .max_keysize    =       AES_MAX_KEY_SIZE,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_aes_ecb,
                        .decrypt        =       hifn_decrypt_aes_ecb,
                },
        },
        {
                .name = "cbc(aes)", .drv_name = "cbc-aes", .bsize = 16,
                .skcipher = {
                        .ivsize         =       HIFN_AES_IV_LENGTH,
                        .min_keysize    =       AES_MIN_KEY_SIZE,
                        .max_keysize    =       AES_MAX_KEY_SIZE,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_aes_cbc,
                        .decrypt        =       hifn_decrypt_aes_cbc,
                },
        },
        {
                .name = "cfb(aes)", .drv_name = "cfb-aes", .bsize = 16,
                .skcipher = {
                        .min_keysize    =       AES_MIN_KEY_SIZE,
                        .max_keysize    =       AES_MAX_KEY_SIZE,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_aes_cfb,
                        .decrypt        =       hifn_decrypt_aes_cfb,
                },
        },
        {
                .name = "ofb(aes)", .drv_name = "ofb-aes", .bsize = 16,
                .skcipher = {
                        .min_keysize    =       AES_MIN_KEY_SIZE,
                        .max_keysize    =       AES_MAX_KEY_SIZE,
                        .setkey         =       hifn_setkey,
                        .encrypt        =       hifn_encrypt_aes_ofb,
                        .decrypt        =       hifn_decrypt_aes_ofb,
                },
        },
};

static int hifn_init_tfm(struct crypto_skcipher *tfm)
{
        struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
        struct hifn_crypto_alg *ha = crypto_alg_to_hifn(alg);
        struct hifn_context *ctx = crypto_skcipher_ctx(tfm);

        ctx->dev = ha->dev;
        crypto_skcipher_set_reqsize(tfm, sizeof(struct hifn_request_context));

        return 0;
}

static int hifn_alg_alloc(struct hifn_device *dev, const struct hifn_alg_template *t)
{
        struct hifn_crypto_alg *alg;
        int err;

        alg = kzalloc(sizeof(*alg), GFP_KERNEL);
        if (!alg)
                return -ENOMEM;

        alg->alg = t->skcipher;
        alg->alg.init = hifn_init_tfm;

        snprintf(alg->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", t->name);
        snprintf(alg->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s-%s",
                 t->drv_name, dev->name);

        alg->alg.base.cra_priority = 300;
        alg->alg.base.cra_flags = CRYPTO_ALG_KERN_DRIVER_ONLY | CRYPTO_ALG_ASYNC;
        alg->alg.base.cra_blocksize = t->bsize;
        alg->alg.base.cra_ctxsize = sizeof(struct hifn_context);
        alg->alg.base.cra_alignmask = 0;
        alg->alg.base.cra_module = THIS_MODULE;

        alg->dev = dev;

        list_add_tail(&alg->entry, &dev->alg_list);

        err = crypto_register_skcipher(&alg->alg);
        if (err) {
                list_del(&alg->entry);
                kfree(alg);
        }

        return err;
}

static void hifn_unregister_alg(struct hifn_device *dev)
{
        struct hifn_crypto_alg *a, *n;

        list_for_each_entry_safe(a, n, &dev->alg_list, entry) {
                list_del(&a->entry);
                crypto_unregister_skcipher(&a->alg);
                kfree(a);
        }
}

static int hifn_register_alg(struct hifn_device *dev)
{
        int i, err;

        for (i = 0; i < ARRAY_SIZE(hifn_alg_templates); ++i) {
                err = hifn_alg_alloc(dev, &hifn_alg_templates[i]);
                if (err)
                        goto err_out_exit;
        }

        return 0;

err_out_exit:
        hifn_unregister_alg(dev);
        return err;
}

static void hifn_tasklet_callback(unsigned long data)
{
        struct hifn_device *dev = (struct hifn_device *)data;

        /*
         * This is ok to call this without lock being held,
         * althogh it modifies some parameters used in parallel,
         * (like dev->success), but they are used in process
         * context or update is atomic (like setting dev->sa[i] to NULL).
         */
        hifn_clear_rings(dev, 0);

        if (dev->started < HIFN_QUEUE_LENGTH && dev->queue.qlen)
                hifn_process_queue(dev);
}

static int hifn_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
        int err, i;
        struct hifn_device *dev;
        char name[8];

        err = pci_enable_device(pdev);
        if (err)
                return err;
        pci_set_master(pdev);

        err = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
        if (err)
                goto err_out_disable_pci_device;

        snprintf(name, sizeof(name), "hifn%d",
                        atomic_inc_return(&hifn_dev_number) - 1);

        err = pci_request_regions(pdev, name);
        if (err)
                goto err_out_disable_pci_device;

        if (pci_resource_len(pdev, 0) < HIFN_BAR0_SIZE ||
            pci_resource_len(pdev, 1) < HIFN_BAR1_SIZE ||
            pci_resource_len(pdev, 2) < HIFN_BAR2_SIZE) {
                dev_err(&pdev->dev, "Broken hardware - I/O regions are too small.\n");
                err = -ENODEV;
                goto err_out_free_regions;
        }

        dev = kzalloc(sizeof(struct hifn_device) + sizeof(struct crypto_alg),
                        GFP_KERNEL);
        if (!dev) {
                err = -ENOMEM;
                goto err_out_free_regions;
        }

        INIT_LIST_HEAD(&dev->alg_list);

        snprintf(dev->name, sizeof(dev->name), "%s", name);
        spin_lock_init(&dev->lock);

        for (i = 0; i < 3; ++i) {
                unsigned long addr, size;

                addr = pci_resource_start(pdev, i);
                size = pci_resource_len(pdev, i);

                dev->bar[i] = ioremap(addr, size);
                if (!dev->bar[i]) {
                        err = -ENOMEM;
                        goto err_out_unmap_bars;
                }
        }

        dev->desc_virt = pci_zalloc_consistent(pdev, sizeof(struct hifn_dma),
                                               &dev->desc_dma);
        if (!dev->desc_virt) {
                dev_err(&pdev->dev, "Failed to allocate descriptor rings.\n");
                err = -ENOMEM;
                goto err_out_unmap_bars;
        }

        dev->pdev = pdev;
        dev->irq = pdev->irq;

        for (i = 0; i < HIFN_D_RES_RSIZE; ++i)
                dev->sa[i] = NULL;

        pci_set_drvdata(pdev, dev);

        tasklet_init(&dev->tasklet, hifn_tasklet_callback, (unsigned long)dev);

        crypto_init_queue(&dev->queue, 1);

        err = request_irq(dev->irq, hifn_interrupt, IRQF_SHARED, dev->name, dev);
        if (err) {
                dev_err(&pdev->dev, "Failed to request IRQ%d: err: %d.\n",
                        dev->irq, err);
                dev->irq = 0;
                goto err_out_free_desc;
        }

        err = hifn_start_device(dev);
        if (err)
                goto err_out_free_irq;

        err = hifn_register_rng(dev);
        if (err)
                goto err_out_stop_device;

        err = hifn_register_alg(dev);
        if (err)
                goto err_out_unregister_rng;

        INIT_DELAYED_WORK(&dev->work, hifn_work);
        schedule_delayed_work(&dev->work, HZ);

        dev_dbg(&pdev->dev, "HIFN crypto accelerator card at %s has been "
                "successfully registered as %s.\n",
                pci_name(pdev), dev->name);

        return 0;

err_out_unregister_rng:
        hifn_unregister_rng(dev);
err_out_stop_device:
        hifn_reset_dma(dev, 1);
        hifn_stop_device(dev);
err_out_free_irq:
        free_irq(dev->irq, dev);
        tasklet_kill(&dev->tasklet);
err_out_free_desc:
        pci_free_consistent(pdev, sizeof(struct hifn_dma),
                        dev->desc_virt, dev->desc_dma);

err_out_unmap_bars:
        for (i = 0; i < 3; ++i)
                if (dev->bar[i])
                        iounmap(dev->bar[i]);
        kfree(dev);

err_out_free_regions:
        pci_release_regions(pdev);

err_out_disable_pci_device:
        pci_disable_device(pdev);

        return err;
}

static void hifn_remove(struct pci_dev *pdev)
{
        int i;
        struct hifn_device *dev;

        dev = pci_get_drvdata(pdev);

        if (dev) {
                cancel_delayed_work_sync(&dev->work);

                hifn_unregister_rng(dev);
                hifn_unregister_alg(dev);
                hifn_reset_dma(dev, 1);
                hifn_stop_device(dev);

                free_irq(dev->irq, dev);
                tasklet_kill(&dev->tasklet);

                hifn_flush(dev);

                pci_free_consistent(pdev, sizeof(struct hifn_dma),
                                dev->desc_virt, dev->desc_dma);
                for (i = 0; i < 3; ++i)
                        if (dev->bar[i])
                                iounmap(dev->bar[i]);

                kfree(dev);
        }

        pci_release_regions(pdev);
        pci_disable_device(pdev);
}

static struct pci_device_id hifn_pci_tbl[] = {
        { PCI_DEVICE(PCI_VENDOR_ID_HIFN, PCI_DEVICE_ID_HIFN_7955) },
        { PCI_DEVICE(PCI_VENDOR_ID_HIFN, PCI_DEVICE_ID_HIFN_7956) },
        { 0 }
};
MODULE_DEVICE_TABLE(pci, hifn_pci_tbl);

static struct pci_driver hifn_pci_driver = {
        .name     = "hifn795x",
        .id_table = hifn_pci_tbl,
        .probe    = hifn_probe,
        .remove   = hifn_remove,
};

static int __init hifn_init(void)
{
        unsigned int freq;
        int err;

        /* HIFN supports only 32-bit addresses */
        BUILD_BUG_ON(sizeof(dma_addr_t) != 4);

        if (strncmp(hifn_pll_ref, "ext", 3) &&
            strncmp(hifn_pll_ref, "pci", 3)) {
                pr_err("hifn795x: invalid hifn_pll_ref clock, must be pci or ext");
                return -EINVAL;
        }

        /*
         * For the 7955/7956 the reference clock frequency must be in the
         * range of 20MHz-100MHz. For the 7954 the upper bound is 66.67MHz,
         * but this chip is currently not supported.
         */
        if (hifn_pll_ref[3] != '\0') {
                freq = simple_strtoul(hifn_pll_ref + 3, NULL, 10);
                if (freq < 20 || freq > 100) {
                        pr_err("hifn795x: invalid hifn_pll_ref frequency, must"
                               "be in the range of 20-100");
                        return -EINVAL;
                }
        }

        err = pci_register_driver(&hifn_pci_driver);
        if (err < 0) {
                pr_err("Failed to register PCI driver for %s device.\n",
                       hifn_pci_driver.name);
                return -ENODEV;
        }

        pr_info("Driver for HIFN 795x crypto accelerator chip "
                "has been successfully registered.\n");

        return 0;
}

static void __exit hifn_fini(void)
{
        pci_unregister_driver(&hifn_pci_driver);

        pr_info("Driver for HIFN 795x crypto accelerator chip "
                "has been successfully unregistered.\n");
}

module_init(hifn_init);
module_exit(hifn_fini);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
MODULE_DESCRIPTION("Driver for HIFN 795x crypto accelerator chip.");