/*
 * AMD Cryptographic Coprocessor (CCP) driver
 *
 * Copyright (C) 2013,2017 Advanced Micro Devices, Inc.
 *
 * Author: Tom Lendacky <thomas.lendacky@amd.com>
 * Author: Gary R Hook <gary.hook@amd.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef __CCP_DEV_H__
#define __CCP_DEV_H__

#include <linux/device.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/dmapool.h>
#include <linux/hw_random.h>
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/irqreturn.h>
#include <linux/dmaengine.h>

#include "sp-dev.h"

#define MAX_CCP_NAME_LEN                16
#define MAX_DMAPOOL_NAME_LEN            32

#define MAX_HW_QUEUES                   5
#define MAX_CMD_QLEN                    100

#define TRNG_RETRIES                    10

#define CACHE_NONE                      0x00
#define CACHE_WB_NO_ALLOC               0xb7

/****** Register Mappings ******/
#define Q_MASK_REG                      0x000
#define TRNG_OUT_REG                    0x00c
#define IRQ_MASK_REG                    0x040
#define IRQ_STATUS_REG                  0x200

#define DEL_CMD_Q_JOB                   0x124
#define DEL_Q_ACTIVE                    0x00000200
#define DEL_Q_ID_SHIFT                  6

#define CMD_REQ0                        0x180
#define CMD_REQ_INCR                    0x04

#define CMD_Q_STATUS_BASE               0x210
#define CMD_Q_INT_STATUS_BASE           0x214
#define CMD_Q_STATUS_INCR               0x20

#define CMD_Q_CACHE_BASE                0x228
#define CMD_Q_CACHE_INC                 0x20

#define CMD_Q_ERROR(__qs)               ((__qs) & 0x0000003f)
#define CMD_Q_DEPTH(__qs)               (((__qs) >> 12) & 0x0000000f)

/* ------------------------ CCP Version 5 Specifics ------------------------ */
#define CMD5_QUEUE_MASK_OFFSET          0x00
#define CMD5_QUEUE_PRIO_OFFSET          0x04
#define CMD5_REQID_CONFIG_OFFSET        0x08
#define CMD5_CMD_TIMEOUT_OFFSET         0x10
#define LSB_PUBLIC_MASK_LO_OFFSET       0x18
#define LSB_PUBLIC_MASK_HI_OFFSET       0x1C
#define LSB_PRIVATE_MASK_LO_OFFSET      0x20
#define LSB_PRIVATE_MASK_HI_OFFSET      0x24
#define CMD5_PSP_CCP_VERSION            0x100

#define CMD5_Q_CONTROL_BASE             0x0000
#define CMD5_Q_TAIL_LO_BASE             0x0004
#define CMD5_Q_HEAD_LO_BASE             0x0008
#define CMD5_Q_INT_ENABLE_BASE          0x000C
#define CMD5_Q_INTERRUPT_STATUS_BASE    0x0010

#define CMD5_Q_STATUS_BASE              0x0100
#define CMD5_Q_INT_STATUS_BASE          0x0104
#define CMD5_Q_DMA_STATUS_BASE          0x0108
#define CMD5_Q_DMA_READ_STATUS_BASE     0x010C
#define CMD5_Q_DMA_WRITE_STATUS_BASE    0x0110
#define CMD5_Q_ABORT_BASE               0x0114
#define CMD5_Q_AX_CACHE_BASE            0x0118

#define CMD5_CONFIG_0_OFFSET            0x6000
#define CMD5_TRNG_CTL_OFFSET            0x6008
#define CMD5_AES_MASK_OFFSET            0x6010
#define CMD5_CLK_GATE_CTL_OFFSET        0x603C

/* Address offset between two virtual queue registers */
#define CMD5_Q_STATUS_INCR              0x1000

/* Bit masks */
#define CMD5_Q_RUN                      0x1
#define CMD5_Q_HALT                     0x2
#define CMD5_Q_MEM_LOCATION             0x4
#define CMD5_Q_SIZE                     0x1F
#define CMD5_Q_SHIFT                    3
#define COMMANDS_PER_QUEUE              16
#define QUEUE_SIZE_VAL                  ((ffs(COMMANDS_PER_QUEUE) - 2) & \
                                          CMD5_Q_SIZE)
#define Q_PTR_MASK                      (2 << (QUEUE_SIZE_VAL + 5) - 1)
#define Q_DESC_SIZE                     sizeof(struct ccp5_desc)
#define Q_SIZE(n)                       (COMMANDS_PER_QUEUE*(n))

#define INT_COMPLETION                  0x1
#define INT_ERROR                       0x2
#define INT_QUEUE_STOPPED               0x4
#define INT_EMPTY_QUEUE                 0x8
#define SUPPORTED_INTERRUPTS            (INT_COMPLETION | INT_ERROR)

#define LSB_REGION_WIDTH                5
#define MAX_LSB_CNT                     8

#define LSB_SIZE                        16
#define LSB_ITEM_SIZE                   32
#define PLSB_MAP_SIZE                   (LSB_SIZE)
#define SLSB_MAP_SIZE                   (MAX_LSB_CNT * LSB_SIZE)

#define LSB_ENTRY_NUMBER(LSB_ADDR)      (LSB_ADDR / LSB_ITEM_SIZE)

/* ------------------------ CCP Version 3 Specifics ------------------------ */
#define REQ0_WAIT_FOR_WRITE             0x00000004
#define REQ0_INT_ON_COMPLETE            0x00000002
#define REQ0_STOP_ON_COMPLETE           0x00000001

#define REQ0_CMD_Q_SHIFT                9
#define REQ0_JOBID_SHIFT                3

/****** REQ1 Related Values ******/
#define REQ1_PROTECT_SHIFT              27
#define REQ1_ENGINE_SHIFT               23
#define REQ1_KEY_KSB_SHIFT              2

#define REQ1_EOM                        0x00000002
#define REQ1_INIT                       0x00000001

/* AES Related Values */
#define REQ1_AES_TYPE_SHIFT             21
#define REQ1_AES_MODE_SHIFT             18
#define REQ1_AES_ACTION_SHIFT           17
#define REQ1_AES_CFB_SIZE_SHIFT         10

/* XTS-AES Related Values */
#define REQ1_XTS_AES_SIZE_SHIFT         10

/* SHA Related Values */
#define REQ1_SHA_TYPE_SHIFT             21

/* RSA Related Values */
#define REQ1_RSA_MOD_SIZE_SHIFT         10

/* Pass-Through Related Values */
#define REQ1_PT_BW_SHIFT                12
#define REQ1_PT_BS_SHIFT                10

/* ECC Related Values */
#define REQ1_ECC_AFFINE_CONVERT         0x00200000
#define REQ1_ECC_FUNCTION_SHIFT         18

/****** REQ4 Related Values ******/
#define REQ4_KSB_SHIFT                  18
#define REQ4_MEMTYPE_SHIFT              16

/****** REQ6 Related Values ******/
#define REQ6_MEMTYPE_SHIFT              16

/****** Key Storage Block ******/
#define KSB_START                       77
#define KSB_END                         127
#define KSB_COUNT                       (KSB_END - KSB_START + 1)
#define CCP_SB_BITS                     256

#define CCP_JOBID_MASK                  0x0000003f

/* ------------------------ General CCP Defines ------------------------ */

#define CCP_DMA_DFLT                    0x0
#define CCP_DMA_PRIV                    0x1
#define CCP_DMA_PUB                     0x2

#define CCP_DMAPOOL_MAX_SIZE            64
#define CCP_DMAPOOL_ALIGN               BIT(5)

#define CCP_REVERSE_BUF_SIZE            64

#define CCP_AES_KEY_SB_COUNT            1
#define CCP_AES_CTX_SB_COUNT            1

#define CCP_XTS_AES_KEY_SB_COUNT        1
#define CCP5_XTS_AES_KEY_SB_COUNT       2
#define CCP_XTS_AES_CTX_SB_COUNT        1

#define CCP_DES3_KEY_SB_COUNT           1
#define CCP_DES3_CTX_SB_COUNT           1

#define CCP_SHA_SB_COUNT                1

#define CCP_RSA_MAX_WIDTH               4096
#define CCP5_RSA_MAX_WIDTH              16384

#define CCP_PASSTHRU_BLOCKSIZE          256
#define CCP_PASSTHRU_MASKSIZE           32
#define CCP_PASSTHRU_SB_COUNT           1

#define CCP_ECC_MODULUS_BYTES           48      /* 384-bits */
#define CCP_ECC_MAX_OPERANDS            6
#define CCP_ECC_MAX_OUTPUTS             3
#define CCP_ECC_SRC_BUF_SIZE            448
#define CCP_ECC_DST_BUF_SIZE            192
#define CCP_ECC_OPERAND_SIZE            64
#define CCP_ECC_OUTPUT_SIZE             64
#define CCP_ECC_RESULT_OFFSET           60
#define CCP_ECC_RESULT_SUCCESS          0x0001

#define CCP_SB_BYTES                    32

struct ccp_op;
struct ccp_device;
struct ccp_cmd;
struct ccp_fns;

struct ccp_dma_cmd {
        struct list_head entry;

        struct ccp_cmd ccp_cmd;
};

struct ccp_dma_desc {
        struct list_head entry;

        struct ccp_device *ccp;

        struct list_head pending;
        struct list_head active;

        enum dma_status status;
        struct dma_async_tx_descriptor tx_desc;
        size_t len;
};

struct ccp_dma_chan {
        struct ccp_device *ccp;

        spinlock_t lock;
        struct list_head created;
        struct list_head pending;
        struct list_head active;
        struct list_head complete;

        struct tasklet_struct cleanup_tasklet;

        enum dma_status status;
        struct dma_chan dma_chan;
};

struct ccp_cmd_queue {
        struct ccp_device *ccp;

        /* Queue identifier */
        u32 id;

        /* Queue dma pool */
        struct dma_pool *dma_pool;

        /* Queue base address (not neccessarily aligned)*/
        struct ccp5_desc *qbase;

        /* Aligned queue start address (per requirement) */
        struct mutex q_mutex ____cacheline_aligned;
        unsigned int qidx;

        /* Version 5 has different requirements for queue memory */
        unsigned int qsize;
        dma_addr_t qbase_dma;
        dma_addr_t qdma_tail;

        /* Per-queue reserved storage block(s) */
        u32 sb_key;
        u32 sb_ctx;

        /* Bitmap of LSBs that can be accessed by this queue */
        DECLARE_BITMAP(lsbmask, MAX_LSB_CNT);
        /* Private LSB that is assigned to this queue, or -1 if none.
         * Bitmap for my private LSB, unused otherwise
         */
        int lsb;
        DECLARE_BITMAP(lsbmap, PLSB_MAP_SIZE);

        /* Queue processing thread */
        struct task_struct *kthread;
        unsigned int active;
        unsigned int suspended;

        /* Number of free command slots available */
        unsigned int free_slots;

        /* Interrupt masks */
        u32 int_ok;
        u32 int_err;

        /* Register addresses for queue */
        void __iomem *reg_control;
        void __iomem *reg_tail_lo;
        void __iomem *reg_head_lo;
        void __iomem *reg_int_enable;
        void __iomem *reg_interrupt_status;
        void __iomem *reg_status;
        void __iomem *reg_int_status;
        void __iomem *reg_dma_status;
        void __iomem *reg_dma_read_status;
        void __iomem *reg_dma_write_status;
        u32 qcontrol; /* Cached control register */

        /* Status values from job */
        u32 int_status;
        u32 q_status;
        u32 q_int_status;
        u32 cmd_error;

        /* Interrupt wait queue */
        wait_queue_head_t int_queue;
        unsigned int int_rcvd;

        /* Per-queue Statistics */
        unsigned long total_ops;
        unsigned long total_aes_ops;
        unsigned long total_xts_aes_ops;
        unsigned long total_3des_ops;
        unsigned long total_sha_ops;
        unsigned long total_rsa_ops;
        unsigned long total_pt_ops;
        unsigned long total_ecc_ops;
} ____cacheline_aligned;

struct ccp_device {
        struct list_head entry;

        struct ccp_vdata *vdata;
        unsigned int ord;
        char name[MAX_CCP_NAME_LEN];
        char rngname[MAX_CCP_NAME_LEN];

        struct device *dev;
        struct sp_device *sp;

        /* Bus specific device information
         */
        void *dev_specific;
        unsigned int qim;
        unsigned int irq;
        bool use_tasklet;
        struct tasklet_struct irq_tasklet;

        /* I/O area used for device communication. The register mapping
         * starts at an offset into the mapped bar.
         *   The CMD_REQx registers and the Delete_Cmd_Queue_Job register
         *   need to be protected while a command queue thread is accessing
         *   them.
         */
        struct mutex req_mutex ____cacheline_aligned;
        void __iomem *io_regs;

        /* Master lists that all cmds are queued on. Because there can be
         * more than one CCP command queue that can process a cmd a separate
         * backlog list is neeeded so that the backlog completion call
         * completes before the cmd is available for execution.
         */
        spinlock_t cmd_lock ____cacheline_aligned;
        unsigned int cmd_count;
        struct list_head cmd;
        struct list_head backlog;

        /* The command queues. These represent the queues available on the
         * CCP that are available for processing cmds
         */
        struct ccp_cmd_queue cmd_q[MAX_HW_QUEUES];
        unsigned int cmd_q_count;

        /* Support for the CCP True RNG
         */
        struct hwrng hwrng;
        unsigned int hwrng_retries;

        /* Support for the CCP DMA capabilities
         */
        struct dma_device dma_dev;
        struct ccp_dma_chan *ccp_dma_chan;
        struct kmem_cache *dma_cmd_cache;
        struct kmem_cache *dma_desc_cache;

        /* A counter used to generate job-ids for cmds submitted to the CCP
         */
        atomic_t current_id ____cacheline_aligned;

        /* The v3 CCP uses key storage blocks (SB) to maintain context for
         * certain operations. To prevent multiple cmds from using the same
         * SB range a command queue reserves an SB range for the duration of
         * the cmd. Each queue, will however, reserve 2 SB blocks for
         * operations that only require single SB entries (eg. AES context/iv
         * and key) in order to avoid allocation contention.  This will reserve
         * at most 10 SB entries, leaving 40 SB entries available for dynamic
         * allocation.
         *
         * The v5 CCP Local Storage Block (LSB) is broken up into 8
         * memrory ranges, each of which can be enabled for access by one
         * or more queues. Device initialization takes this into account,
         * and attempts to assign one region for exclusive use by each
         * available queue; the rest are then aggregated as "public" use.
         * If there are fewer regions than queues, all regions are shared
         * amongst all queues.
         */
        struct mutex sb_mutex ____cacheline_aligned;
        DECLARE_BITMAP(sb, KSB_COUNT);
        wait_queue_head_t sb_queue;
        unsigned int sb_avail;
        unsigned int sb_count;
        u32 sb_start;

        /* Bitmap of shared LSBs, if any */
        DECLARE_BITMAP(lsbmap, SLSB_MAP_SIZE);

        /* Suspend support */
        unsigned int suspending;
        wait_queue_head_t suspend_queue;

        /* DMA caching attribute support */
        unsigned int axcache;

        /* Device Statistics */
        unsigned long total_interrupts;

        /* DebugFS info */
        struct dentry *debugfs_instance;
};

enum ccp_memtype {
        CCP_MEMTYPE_SYSTEM = 0,
        CCP_MEMTYPE_SB,
        CCP_MEMTYPE_LOCAL,
        CCP_MEMTYPE__LAST,
};
#define CCP_MEMTYPE_LSB CCP_MEMTYPE_KSB


struct ccp_dma_info {
        dma_addr_t address;
        unsigned int offset;
        unsigned int length;
        enum dma_data_direction dir;
} __packed __aligned(4);

struct ccp_dm_workarea {
        struct device *dev;
        struct dma_pool *dma_pool;

        u8 *address;
        struct ccp_dma_info dma;
        unsigned int length;
};

struct ccp_sg_workarea {
        struct scatterlist *sg;
        int nents;
        unsigned int sg_used;

        struct scatterlist *dma_sg;
        struct device *dma_dev;
        unsigned int dma_count;
        enum dma_data_direction dma_dir;

        u64 bytes_left;
};

struct ccp_data {
        struct ccp_sg_workarea sg_wa;
        struct ccp_dm_workarea dm_wa;
};

struct ccp_mem {
        enum ccp_memtype type;
        union {
                struct ccp_dma_info dma;
                u32 sb;
        } u;
};

struct ccp_aes_op {
        enum ccp_aes_type type;
        enum ccp_aes_mode mode;
        enum ccp_aes_action action;
        unsigned int size;
};

struct ccp_xts_aes_op {
        enum ccp_aes_type type;
        enum ccp_aes_action action;
        enum ccp_xts_aes_unit_size unit_size;
};

struct ccp_des3_op {
        enum ccp_des3_type type;
        enum ccp_des3_mode mode;
        enum ccp_des3_action action;
};

struct ccp_sha_op {
        enum ccp_sha_type type;
        u64 msg_bits;
};

struct ccp_rsa_op {
        u32 mod_size;
        u32 input_len;
};

struct ccp_passthru_op {
        enum ccp_passthru_bitwise bit_mod;
        enum ccp_passthru_byteswap byte_swap;
};

struct ccp_ecc_op {
        enum ccp_ecc_function function;
};

struct ccp_op {
        struct ccp_cmd_queue *cmd_q;

        u32 jobid;
        u32 ioc;
        u32 soc;
        u32 sb_key;
        u32 sb_ctx;
        u32 init;
        u32 eom;

        struct ccp_mem src;
        struct ccp_mem dst;
        struct ccp_mem exp;

        union {
                struct ccp_aes_op aes;
                struct ccp_xts_aes_op xts;
                struct ccp_des3_op des3;
                struct ccp_sha_op sha;
                struct ccp_rsa_op rsa;
                struct ccp_passthru_op passthru;
                struct ccp_ecc_op ecc;
        } u;
};

static inline u32 ccp_addr_lo(struct ccp_dma_info *info)
{
        return lower_32_bits(info->address + info->offset);
}

static inline u32 ccp_addr_hi(struct ccp_dma_info *info)
{
        return upper_32_bits(info->address + info->offset) & 0x0000ffff;
}

/**
 * descriptor for version 5 CPP commands
 * 8 32-bit words:
 * word 0: function; engine; control bits
 * word 1: length of source data
 * word 2: low 32 bits of source pointer
 * word 3: upper 16 bits of source pointer; source memory type
 * word 4: low 32 bits of destination pointer
 * word 5: upper 16 bits of destination pointer; destination memory type
 * word 6: low 32 bits of key pointer
 * word 7: upper 16 bits of key pointer; key memory type
 */
struct dword0 {
        unsigned int soc:1;
        unsigned int ioc:1;
        unsigned int rsvd1:1;
        unsigned int init:1;
        unsigned int eom:1;             /* AES/SHA only */
        unsigned int function:15;
        unsigned int engine:4;
        unsigned int prot:1;
        unsigned int rsvd2:7;
};

struct dword3 {
        unsigned int  src_hi:16;
        unsigned int  src_mem:2;
        unsigned int  lsb_cxt_id:8;
        unsigned int  rsvd1:5;
        unsigned int  fixed:1;
};

union dword4 {
        __le32 dst_lo;          /* NON-SHA      */
        __le32 sha_len_lo;      /* SHA          */
};

union dword5 {
        struct {
                unsigned int  dst_hi:16;
                unsigned int  dst_mem:2;
                unsigned int  rsvd1:13;
                unsigned int  fixed:1;
        } fields;
        __le32 sha_len_hi;
};

struct dword7 {
        unsigned int  key_hi:16;
        unsigned int  key_mem:2;
        unsigned int  rsvd1:14;
};

struct ccp5_desc {
        struct dword0 dw0;
        __le32 length;
        __le32 src_lo;
        struct dword3 dw3;
        union dword4 dw4;
        union dword5 dw5;
        __le32 key_lo;
        struct dword7 dw7;
};

void ccp_add_device(struct ccp_device *ccp);
void ccp_del_device(struct ccp_device *ccp);

extern void ccp_log_error(struct ccp_device *, int);

struct ccp_device *ccp_alloc_struct(struct sp_device *sp);
bool ccp_queues_suspended(struct ccp_device *ccp);
int ccp_cmd_queue_thread(void *data);
int ccp_trng_read(struct hwrng *rng, void *data, size_t max, bool wait);

int ccp_run_cmd(struct ccp_cmd_queue *cmd_q, struct ccp_cmd *cmd);

int ccp_register_rng(struct ccp_device *ccp);
void ccp_unregister_rng(struct ccp_device *ccp);
int ccp_dmaengine_register(struct ccp_device *ccp);
void ccp_dmaengine_unregister(struct ccp_device *ccp);

void ccp5_debugfs_setup(struct ccp_device *ccp);
void ccp5_debugfs_destroy(void);

/* Structure for computation functions that are device-specific */
struct ccp_actions {
        int (*aes)(struct ccp_op *);
        int (*xts_aes)(struct ccp_op *);
        int (*des3)(struct ccp_op *);
        int (*sha)(struct ccp_op *);
        int (*rsa)(struct ccp_op *);
        int (*passthru)(struct ccp_op *);
        int (*ecc)(struct ccp_op *);
        u32 (*sballoc)(struct ccp_cmd_queue *, unsigned int);
        void (*sbfree)(struct ccp_cmd_queue *, unsigned int, unsigned int);
        unsigned int (*get_free_slots)(struct ccp_cmd_queue *);
        int (*init)(struct ccp_device *);
        void (*destroy)(struct ccp_device *);
        irqreturn_t (*irqhandler)(int, void *);
};

extern const struct ccp_vdata ccpv3_platform;
extern const struct ccp_vdata ccpv3;
extern const struct ccp_vdata ccpv5a;
extern const struct ccp_vdata ccpv5b;

#endif