/* SPDX-License-Identifier: GPL-2.0 */
/*
 * sun8i-ss.h - hardware cryptographic offloader for
 * Allwinner A80/A83T SoC
 *
 * Copyright (C) 2016-2019 Corentin LABBE <clabbe.montjoie@gmail.com>
 */
#include <crypto/aes.h>
#include <crypto/des.h>
#include <crypto/engine.h>
#include <crypto/rng.h>
#include <crypto/skcipher.h>
#include <linux/atomic.h>
#include <linux/debugfs.h>
#include <linux/crypto.h>
#include <crypto/internal/hash.h>
#include <crypto/md5.h>
#include <crypto/sha1.h>
#include <crypto/sha2.h>

#define SS_START        1

#define SS_ENCRYPTION           0
#define SS_DECRYPTION           BIT(6)

#define SS_ALG_AES              0
#define SS_ALG_DES              (1 << 2)
#define SS_ALG_3DES             (2 << 2)
#define SS_ALG_MD5              (3 << 2)
#define SS_ALG_PRNG             (4 << 2)
#define SS_ALG_SHA1             (6 << 2)
#define SS_ALG_SHA224           (7 << 2)
#define SS_ALG_SHA256           (8 << 2)

#define SS_CTL_REG              0x00
#define SS_INT_CTL_REG          0x04
#define SS_INT_STA_REG          0x08
#define SS_KEY_ADR_REG          0x10
#define SS_IV_ADR_REG           0x18
#define SS_SRC_ADR_REG          0x20
#define SS_DST_ADR_REG          0x28
#define SS_LEN_ADR_REG          0x30

#define SS_ID_NOTSUPP           0xFF

#define SS_ID_CIPHER_AES        0
#define SS_ID_CIPHER_DES        1
#define SS_ID_CIPHER_DES3       2
#define SS_ID_CIPHER_MAX        3

#define SS_ID_OP_ECB    0
#define SS_ID_OP_CBC    1
#define SS_ID_OP_MAX    2

#define SS_AES_128BITS 0
#define SS_AES_192BITS 1
#define SS_AES_256BITS 2

#define SS_OP_ECB       0
#define SS_OP_CBC       (1 << 13)

#define SS_ID_HASH_MD5  0
#define SS_ID_HASH_SHA1 1
#define SS_ID_HASH_SHA224       2
#define SS_ID_HASH_SHA256       3
#define SS_ID_HASH_MAX  4

#define SS_FLOW0        BIT(30)
#define SS_FLOW1        BIT(31)

#define SS_PRNG_CONTINUE        BIT(18)

#define MAX_SG 8

#define MAXFLOW 2

#define SS_MAX_CLOCKS 2

#define SS_DIE_ID_SHIFT 20
#define SS_DIE_ID_MASK  0x07

#define PRNG_DATA_SIZE (160 / 8)
#define PRNG_SEED_SIZE DIV_ROUND_UP(175, 8)

#define MAX_PAD_SIZE 4096

/*
 * struct ss_clock - Describe clocks used by sun8i-ss
 * @name:       Name of clock needed by this variant
 * @freq:       Frequency to set for each clock
 * @max_freq:   Maximum frequency for each clock
 */
struct ss_clock {
        const char *name;
        unsigned long freq;
        unsigned long max_freq;
};

/*
 * struct ss_variant - Describe SS capability for each variant hardware
 * @alg_cipher: list of supported ciphers. for each SS_ID_ this will give the
 *              coresponding SS_ALG_XXX value
 * @alg_hash:   list of supported hashes. for each SS_ID_ this will give the
 *              corresponding SS_ALG_XXX value
 * @op_mode:    list of supported block modes
 * @ss_clks:    list of clock needed by this variant
 */
struct ss_variant {
        char alg_cipher[SS_ID_CIPHER_MAX];
        char alg_hash[SS_ID_HASH_MAX];
        u32 op_mode[SS_ID_OP_MAX];
        struct ss_clock ss_clks[SS_MAX_CLOCKS];
};

struct sginfo {
        u32 addr;
        u32 len;
};

/*
 * struct sun8i_ss_flow - Information used by each flow
 * @engine:     ptr to the crypto_engine for this flow
 * @complete:   completion for the current task on this flow
 * @status:     set to 1 by interrupt if task is done
 * @stat_req:   number of request done by this flow
 * @iv:         list of IV to use for each step
 * @biv:        buffer which contain the backuped IV
 * @pad:        padding buffer for hash operations
 * @result:     buffer for storing the result of hash operations
 */
struct sun8i_ss_flow {
        struct crypto_engine *engine;
        struct completion complete;
        int status;
        u8 *iv[MAX_SG];
        u8 *biv;
        void *pad;
        void *result;
#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
        unsigned long stat_req;
#endif
};

/*
 * struct sun8i_ss_dev - main container for all this driver information
 * @base:       base address of SS
 * @ssclks:     clocks used by SS
 * @reset:      pointer to reset controller
 * @dev:        the platform device
 * @mlock:      Control access to device registers
 * @flows:      array of all flow
 * @flow:       flow to use in next request
 * @variant:    pointer to variant specific data
 * @dbgfs_dir:  Debugfs dentry for statistic directory
 * @dbgfs_stats: Debugfs dentry for statistic counters
 */
struct sun8i_ss_dev {
        void __iomem *base;
        struct clk *ssclks[SS_MAX_CLOCKS];
        struct reset_control *reset;
        struct device *dev;
        struct mutex mlock;
        struct sun8i_ss_flow *flows;
        atomic_t flow;
        const struct ss_variant *variant;
#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
        struct dentry *dbgfs_dir;
        struct dentry *dbgfs_stats;
#endif
};

/*
 * struct sun8i_cipher_req_ctx - context for a skcipher request
 * @t_src:              list of mapped SGs with their size
 * @t_dst:              list of mapped SGs with their size
 * @p_key:              DMA address of the key
 * @p_iv:               DMA address of the IVs
 * @niv:                Number of IVs DMA mapped
 * @method:             current algorithm for this request
 * @op_mode:            op_mode for this request
 * @op_dir:             direction (encrypt vs decrypt) for this request
 * @flow:               the flow to use for this request
 * @ivlen:              size of IVs
 * @keylen:             keylen for this request
 * @fallback_req:       request struct for invoking the fallback skcipher TFM
 */
struct sun8i_cipher_req_ctx {
        struct sginfo t_src[MAX_SG];
        struct sginfo t_dst[MAX_SG];
        u32 p_key;
        u32 p_iv[MAX_SG];
        int niv;
        u32 method;
        u32 op_mode;
        u32 op_dir;
        int flow;
        unsigned int ivlen;
        unsigned int keylen;
        struct skcipher_request fallback_req;   // keep at the end
};

/*
 * struct sun8i_cipher_tfm_ctx - context for a skcipher TFM
 * @key:                pointer to key data
 * @keylen:             len of the key
 * @ss:                 pointer to the private data of driver handling this TFM
 * @fallback_tfm:       pointer to the fallback TFM
 */
struct sun8i_cipher_tfm_ctx {
        u32 *key;
        u32 keylen;
        struct sun8i_ss_dev *ss;
        struct crypto_skcipher *fallback_tfm;
};

/*
 * struct sun8i_ss_prng_ctx - context for PRNG TFM
 * @seed:       The seed to use
 * @slen:       The size of the seed
 */
struct sun8i_ss_rng_tfm_ctx {
        void *seed;
        unsigned int slen;
};

/*
 * struct sun8i_ss_hash_tfm_ctx - context for an ahash TFM
 * @fallback_tfm:       pointer to the fallback TFM
 * @ss:                 pointer to the private data of driver handling this TFM
 */
struct sun8i_ss_hash_tfm_ctx {
        struct crypto_ahash *fallback_tfm;
        struct sun8i_ss_dev *ss;
        u8 *ipad;
        u8 *opad;
        u8 key[SHA256_BLOCK_SIZE];
        int keylen;
};

/*
 * struct sun8i_ss_hash_reqctx - context for an ahash request
 * @t_src:      list of DMA address and size for source SGs
 * @t_dst:      list of DMA address and size for destination SGs
 * @fallback_req:       pre-allocated fallback request
 * @method:     the register value for the algorithm used by this request
 * @flow:       the flow to use for this request
 */
struct sun8i_ss_hash_reqctx {
        struct sginfo t_src[MAX_SG];
        struct sginfo t_dst[MAX_SG];
        u32 method;
        int flow;

        /* Must be last as it ends in a flexible-array member. */
        struct ahash_request fallback_req;
};

/*
 * struct sun8i_ss_alg_template - crypto_alg template
 * @type:               the CRYPTO_ALG_TYPE for this template
 * @ss_algo_id:         the SS_ID for this template
 * @ss_blockmode:       the type of block operation SS_ID
 * @ss:                 pointer to the sun8i_ss_dev structure associated with
 *                      this template
 * @alg:                one of sub struct must be used
 * @stat_req:           number of request done on this template
 * @stat_fb:            number of request which has fallbacked
 * @stat_bytes:         total data size done by this template
 */
struct sun8i_ss_alg_template {
        u32 type;
        u32 ss_algo_id;
        u32 ss_blockmode;
        struct sun8i_ss_dev *ss;
        union {
                struct skcipher_engine_alg skcipher;
                struct rng_alg rng;
                struct ahash_engine_alg hash;
        } alg;
        unsigned long stat_req;
        unsigned long stat_fb;
        unsigned long stat_bytes;
        unsigned long stat_fb_len;
        unsigned long stat_fb_sglen;
        unsigned long stat_fb_align;
        unsigned long stat_fb_sgnum;
        char fbname[CRYPTO_MAX_ALG_NAME];
};

int sun8i_ss_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
                        unsigned int keylen);
int sun8i_ss_des3_setkey(struct crypto_skcipher *tfm, const u8 *key,
                         unsigned int keylen);
int sun8i_ss_cipher_init(struct crypto_tfm *tfm);
void sun8i_ss_cipher_exit(struct crypto_tfm *tfm);
int sun8i_ss_handle_cipher_request(struct crypto_engine *engine, void *areq);
int sun8i_ss_skdecrypt(struct skcipher_request *areq);
int sun8i_ss_skencrypt(struct skcipher_request *areq);

int sun8i_ss_get_engine_number(struct sun8i_ss_dev *ss);

int sun8i_ss_run_task(struct sun8i_ss_dev *ss, struct sun8i_cipher_req_ctx *rctx, const char *name);
int sun8i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
                           unsigned int slen, u8 *dst, unsigned int dlen);
int sun8i_ss_prng_seed(struct crypto_rng *tfm, const u8 *seed, unsigned int slen);
int sun8i_ss_prng_init(struct crypto_tfm *tfm);
void sun8i_ss_prng_exit(struct crypto_tfm *tfm);

int sun8i_ss_hash_init_tfm(struct crypto_ahash *tfm);
void sun8i_ss_hash_exit_tfm(struct crypto_ahash *tfm);
int sun8i_ss_hash_init(struct ahash_request *areq);
int sun8i_ss_hash_export(struct ahash_request *areq, void *out);
int sun8i_ss_hash_import(struct ahash_request *areq, const void *in);
int sun8i_ss_hash_final(struct ahash_request *areq);
int sun8i_ss_hash_update(struct ahash_request *areq);
int sun8i_ss_hash_finup(struct ahash_request *areq);
int sun8i_ss_hash_digest(struct ahash_request *areq);
int sun8i_ss_hash_run(struct crypto_engine *engine, void *breq);
int sun8i_ss_hmac_setkey(struct crypto_ahash *ahash, const u8 *key,
                         unsigned int keylen);