/*
 * ICSWX api
 *
 * Copyright (C) 2015 IBM Corp.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * This provides the Initiate Coprocessor Store Word Indexed (ICSWX)
 * instruction.  This instruction is used to communicate with PowerPC
 * coprocessors.  This also provides definitions of the structures used
 * to communicate with the coprocessor.
 *
 * The RFC02130: Coprocessor Architecture document is the reference for
 * everything in this file unless otherwise noted.
 */
#ifndef _ARCH_POWERPC_INCLUDE_ASM_ICSWX_H_
#define _ARCH_POWERPC_INCLUDE_ASM_ICSWX_H_

#include <asm/ppc-opcode.h> /* for PPC_ICSWX */

/* Chapter 6.5.8 Coprocessor-Completion Block (CCB) */

#define CCB_VALUE               (0x3fffffffffffffff)
#define CCB_ADDRESS             (0xfffffffffffffff8)
#define CCB_CM                  (0x0000000000000007)
#define CCB_CM0                 (0x0000000000000004)
#define CCB_CM12                (0x0000000000000003)

#define CCB_CM0_ALL_COMPLETIONS (0x0)
#define CCB_CM0_LAST_IN_CHAIN   (0x4)
#define CCB_CM12_STORE          (0x0)
#define CCB_CM12_INTERRUPT      (0x1)

#define CCB_SIZE                (0x10)
#define CCB_ALIGN               CCB_SIZE

struct coprocessor_completion_block {
        __be64 value;
        __be64 address;
} __packed __aligned(CCB_ALIGN);


/* Chapter 6.5.7 Coprocessor-Status Block (CSB) */

#define CSB_V                   (0x80)
#define CSB_F                   (0x04)
#define CSB_CH                  (0x03)
#define CSB_CE_INCOMPLETE       (0x80)
#define CSB_CE_TERMINATION      (0x40)
#define CSB_CE_TPBC             (0x20)

#define CSB_CC_SUCCESS          (0)
#define CSB_CC_INVALID_ALIGN    (1)
#define CSB_CC_OPERAND_OVERLAP  (2)
#define CSB_CC_DATA_LENGTH      (3)
#define CSB_CC_TRANSLATION      (5)
#define CSB_CC_PROTECTION       (6)
#define CSB_CC_RD_EXTERNAL      (7)
#define CSB_CC_INVALID_OPERAND  (8)
#define CSB_CC_PRIVILEGE        (9)
#define CSB_CC_INTERNAL         (10)
#define CSB_CC_WR_EXTERNAL      (12)
#define CSB_CC_NOSPC            (13)
#define CSB_CC_EXCESSIVE_DDE    (14)
#define CSB_CC_WR_TRANSLATION   (15)
#define CSB_CC_WR_PROTECTION    (16)
#define CSB_CC_UNKNOWN_CODE     (17)
#define CSB_CC_ABORT            (18)
#define CSB_CC_TRANSPORT        (20)
#define CSB_CC_SEGMENTED_DDL    (31)
#define CSB_CC_PROGRESS_POINT   (32)
#define CSB_CC_DDE_OVERFLOW     (33)
#define CSB_CC_SESSION          (34)
#define CSB_CC_PROVISION        (36)
#define CSB_CC_CHAIN            (37)
#define CSB_CC_SEQUENCE         (38)
#define CSB_CC_HW               (39)

#define CSB_SIZE                (0x10)
#define CSB_ALIGN               CSB_SIZE

struct coprocessor_status_block {
        u8 flags;
        u8 cs;
        u8 cc;
        u8 ce;
        __be32 count;
        __be64 address;
} __packed __aligned(CSB_ALIGN);


/* Chapter 6.5.10 Data-Descriptor List (DDL)
 * each list contains one or more Data-Descriptor Entries (DDE)
 */

#define DDE_P                   (0x8000)

#define DDE_SIZE                (0x10)
#define DDE_ALIGN               DDE_SIZE

struct data_descriptor_entry {
        __be16 flags;
        u8 count;
        u8 index;
        __be32 length;
        __be64 address;
} __packed __aligned(DDE_ALIGN);


/* Chapter 6.5.2 Coprocessor-Request Block (CRB) */

#define CRB_SIZE                (0x80)
#define CRB_ALIGN               (0x100) /* Errata: requires 256 alignment */

/* Coprocessor Status Block field
 *   ADDRESS    address of CSB
 *   C          CCB is valid
 *   AT         0 = addrs are virtual, 1 = addrs are phys
 *   M          enable perf monitor
 */
#define CRB_CSB_ADDRESS         (0xfffffffffffffff0)
#define CRB_CSB_C               (0x0000000000000008)
#define CRB_CSB_AT              (0x0000000000000002)
#define CRB_CSB_M               (0x0000000000000001)

struct coprocessor_request_block {
        __be32 ccw;
        __be32 flags;
        __be64 csb_addr;

        struct data_descriptor_entry source;
        struct data_descriptor_entry target;

        struct coprocessor_completion_block ccb;

        u8 reserved[48];

        struct coprocessor_status_block csb;
} __packed __aligned(CRB_ALIGN);


/* RFC02167 Initiate Coprocessor Instructions document
 * Chapter 8.2.1.1.1 RS
 * Chapter 8.2.3 Coprocessor Directive
 * Chapter 8.2.4 Execution
 *
 * The CCW must be converted to BE before passing to icswx()
 */

#define CCW_PS                  (0xff000000)
#define CCW_CT                  (0x00ff0000)
#define CCW_CD                  (0x0000ffff)
#define CCW_CL                  (0x0000c000)


/* RFC02167 Initiate Coprocessor Instructions document
 * Chapter 8.2.1 Initiate Coprocessor Store Word Indexed (ICSWX)
 * Chapter 8.2.4.1 Condition Register 0
 */

#define ICSWX_INITIATED         (0x8)
#define ICSWX_BUSY              (0x4)
#define ICSWX_REJECTED          (0x2)
#define ICSWX_XERS0             (0x1)   /* undefined or set from XERSO. */

static inline int icswx(__be32 ccw, struct coprocessor_request_block *crb)
{
        __be64 ccw_reg = ccw;
        u32 cr;

        __asm__ __volatile__(
        PPC_ICSWX(%1,0,%2) "\n"
        "mfcr %0\n"
        : "=r" (cr)
        : "r" (ccw_reg), "r" (crb)
        : "cr0", "memory");

        return (int)((cr >> 28) & 0xf);
}


#endif /* _ARCH_POWERPC_INCLUDE_ASM_ICSWX_H_ */