/* SPDX-License-Identifier: GPL-2.0 */

#ifndef __NX_842_H__
#define __NX_842_H__

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/ratelimit.h>

/* Restrictions on Data Descriptor List (DDL) and Entry (DDE) buffers
 *
 * From NX P8 workbook, sec 4.9.1 "842 details"
 *   Each DDE buffer is 128 byte aligned
 *   Each DDE buffer size is a multiple of 32 bytes (except the last)
 *   The last DDE buffer size is a multiple of 8 bytes
 */
#define DDE_BUFFER_ALIGN        (128)
#define DDE_BUFFER_SIZE_MULT    (32)
#define DDE_BUFFER_LAST_MULT    (8)

/* Arbitrary DDL length limit
 * Allows max buffer size of MAX-1 to MAX pages
 * (depending on alignment)
 */
#define DDL_LEN_MAX             (17)

/* CCW 842 CI/FC masks
 * NX P8 workbook, section 4.3.1, figure 4-6
 * "CI/FC Boundary by NX CT type"
 */
#define CCW_CI_842              (0x00003ff8)
#define CCW_FC_842              (0x00000007)

/* CCW Function Codes (FC) for 842
 * NX P8 workbook, section 4.9, table 4-28
 * "Function Code Definitions for 842 Memory Compression"
 */
#define CCW_FC_842_COMP_NOCRC   (0)
#define CCW_FC_842_COMP_CRC     (1)
#define CCW_FC_842_DECOMP_NOCRC (2)
#define CCW_FC_842_DECOMP_CRC   (3)
#define CCW_FC_842_MOVE         (4)

/* CSB CC Error Types for 842
 * NX P8 workbook, section 4.10.3, table 4-30
 * "Reported Error Types Summary Table"
 */
/* These are all duplicates of existing codes defined in icswx.h. */
#define CSB_CC_TRANSLATION_DUP1 (80)
#define CSB_CC_TRANSLATION_DUP2 (82)
#define CSB_CC_TRANSLATION_DUP3 (84)
#define CSB_CC_TRANSLATION_DUP4 (86)
#define CSB_CC_TRANSLATION_DUP5 (92)
#define CSB_CC_TRANSLATION_DUP6 (94)
#define CSB_CC_PROTECTION_DUP1  (81)
#define CSB_CC_PROTECTION_DUP2  (83)
#define CSB_CC_PROTECTION_DUP3  (85)
#define CSB_CC_PROTECTION_DUP4  (87)
#define CSB_CC_PROTECTION_DUP5  (93)
#define CSB_CC_PROTECTION_DUP6  (95)
#define CSB_CC_RD_EXTERNAL_DUP1 (89)
#define CSB_CC_RD_EXTERNAL_DUP2 (90)
#define CSB_CC_RD_EXTERNAL_DUP3 (91)
/* These are specific to NX */
/* 842 codes */
#define CSB_CC_TPBC_GT_SPBC     (64) /* no error, but >1 comp ratio */
#define CSB_CC_CRC_MISMATCH     (65) /* decomp crc mismatch */
#define CSB_CC_TEMPL_INVALID    (66) /* decomp invalid template value */
#define CSB_CC_TEMPL_OVERFLOW   (67) /* decomp template shows data after end */
/* sym crypt codes */
#define CSB_CC_DECRYPT_OVERFLOW (64)
/* asym crypt codes */
#define CSB_CC_MINV_OVERFLOW    (128)
/*
 * HW error - Job did not finish in the maximum time allowed.
 * Job terminated.
 */
#define CSB_CC_HW_EXPIRED_TIMER         (224)
/* These are reserved for hypervisor use */
#define CSB_CC_HYP_RESERVE_START        (240)
#define CSB_CC_HYP_RESERVE_END          (253)
#define CSB_CC_HYP_RESERVE_P9_END       (251)
/* No valid interrupt server (P9 or later). */
#define CSB_CC_HYP_RESERVE_NO_INTR_SERVER       (252)
#define CSB_CC_HYP_NO_HW                (254)
#define CSB_CC_HYP_HANG_ABORTED         (255)

/* CCB Completion Modes (CM) for 842
 * NX P8 workbook, section 4.3, figure 4-5
 * "CRB Details - Normal Cop_Req (CL=00, C=1)"
 */
#define CCB_CM_EXTRA_WRITE      (CCB_CM0_ALL_COMPLETIONS & CCB_CM12_STORE)
#define CCB_CM_INTERRUPT        (CCB_CM0_ALL_COMPLETIONS & CCB_CM12_INTERRUPT)

#define LEN_ON_SIZE(pa, size)   ((size) - ((pa) & ((size) - 1)))
#define LEN_ON_PAGE(pa)         LEN_ON_SIZE(pa, PAGE_SIZE)

struct crypto_scomp;

static inline unsigned long nx842_get_pa(void *addr)
{
        if (!is_vmalloc_addr(addr))
                return __pa(addr);

        return page_to_phys(vmalloc_to_page(addr)) + offset_in_page(addr);
}

/**
 * This provides the driver's constraints.  Different nx842 implementations
 * may have varying requirements.  The constraints are:
 *   @alignment:        All buffers should be aligned to this
 *   @multiple:         All buffer lengths should be a multiple of this
 *   @minimum:          Buffer lengths must not be less than this amount
 *   @maximum:          Buffer lengths must not be more than this amount
 *
 * The constraints apply to all buffers and lengths, both input and output,
 * for both compression and decompression, except for the minimum which
 * only applies to compression input and decompression output; the
 * compressed data can be less than the minimum constraint.  It can be
 * assumed that compressed data will always adhere to the multiple
 * constraint.
 *
 * The driver may succeed even if these constraints are violated;
 * however the driver can return failure or suffer reduced performance
 * if any constraint is not met.
 */
struct nx842_constraints {
        int alignment;
        int multiple;
        int minimum;
        int maximum;
};

struct nx842_driver {
        char *name;
        struct module *owner;
        size_t workmem_size;

        struct nx842_constraints *constraints;

        int (*compress)(const unsigned char *in, unsigned int in_len,
                        unsigned char *out, unsigned int *out_len,
                        void *wrkmem);
        int (*decompress)(const unsigned char *in, unsigned int in_len,
                          unsigned char *out, unsigned int *out_len,
                          void *wrkmem);
};

struct nx842_crypto_header_group {
        __be16 padding;                 /* unused bytes at start of group */
        __be32 compressed_length;       /* compressed bytes in group */
        __be32 uncompressed_length;     /* bytes after decompression */
} __packed;

struct nx842_crypto_header {
        /* New members MUST be added within the struct_group() macro below. */
        struct_group_tagged(nx842_crypto_header_hdr, hdr,
                __be16 magic;           /* NX842_CRYPTO_MAGIC */
                __be16 ignore;          /* decompressed end bytes to ignore */
                u8 groups;              /* total groups in this header */
        );
        struct nx842_crypto_header_group group[];
} __packed;
static_assert(offsetof(struct nx842_crypto_header, group) == sizeof(struct nx842_crypto_header_hdr),
              "struct member likely outside of struct_group_tagged()");

#define NX842_CRYPTO_GROUP_MAX  (0x20)

struct nx842_crypto_ctx {
        spinlock_t lock;

        u8 *wmem;
        u8 *sbounce, *dbounce;

        struct nx842_crypto_header_hdr header;
        struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];

        struct nx842_driver *driver;
};

void *nx842_crypto_alloc_ctx(struct nx842_driver *driver);
void nx842_crypto_free_ctx(void *ctx);
int nx842_crypto_compress(struct crypto_scomp *tfm,
                          const u8 *src, unsigned int slen,
                          u8 *dst, unsigned int *dlen, void *ctx);
int nx842_crypto_decompress(struct crypto_scomp *tfm,
                            const u8 *src, unsigned int slen,
                            u8 *dst, unsigned int *dlen, void *ctx);

#endif /* __NX_842_H__ */