// SPDX-License-Identifier: GPL-2.0-only
/*
 * Crypto acceleration support for Rockchip RK3288
 *
 * Copyright (c) 2015, Fuzhou Rockchip Electronics Co., Ltd
 *
 * Author: Zain Wang <zain.wang@rock-chips.com>
 *
 * Some ideas are from marvell/cesa.c and s5p-sss.c driver.
 */

#include <linux/unaligned.h>
#include <crypto/internal/hash.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include "rk3288_crypto.h"

/*
 * IC can not process zero message hash,
 * so we put the fixed hash out when met zero message.
 */

static bool rk_ahash_need_fallback(struct ahash_request *req)
{
        struct scatterlist *sg;

        sg = req->src;
        while (sg) {
                if (!IS_ALIGNED(sg->offset, sizeof(u32))) {
                        return true;
                }
                if (sg->length % 4) {
                        return true;
                }
                sg = sg_next(sg);
        }
        return false;
}

static int rk_ahash_digest_fb(struct ahash_request *areq)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(areq);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
        struct rk_ahash_ctx *tfmctx = crypto_ahash_ctx(tfm);
        struct ahash_alg *alg = crypto_ahash_alg(tfm);
        struct rk_crypto_tmp *algt = container_of(alg, struct rk_crypto_tmp, alg.hash.base);

        algt->stat_fb++;

        ahash_request_set_tfm(&rctx->fallback_req, tfmctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   areq->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   areq->base.complete, areq->base.data);
        ahash_request_set_crypt(&rctx->fallback_req, areq->src, areq->result,
                                areq->nbytes);

        return crypto_ahash_digest(&rctx->fallback_req);
}

static int zero_message_process(struct ahash_request *req)
{
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        int rk_digest_size = crypto_ahash_digestsize(tfm);

        switch (rk_digest_size) {
        case SHA1_DIGEST_SIZE:
                memcpy(req->result, sha1_zero_message_hash, rk_digest_size);
                break;
        case SHA256_DIGEST_SIZE:
                memcpy(req->result, sha256_zero_message_hash, rk_digest_size);
                break;
        case MD5_DIGEST_SIZE:
                memcpy(req->result, md5_zero_message_hash, rk_digest_size);
                break;
        default:
                return -EINVAL;
        }

        return 0;
}

static void rk_ahash_reg_init(struct ahash_request *req,
                              struct rk_crypto_info *dev)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        int reg_status;

        reg_status = CRYPTO_READ(dev, RK_CRYPTO_CTRL) |
                     RK_CRYPTO_HASH_FLUSH | _SBF(0xffff, 16);
        CRYPTO_WRITE(dev, RK_CRYPTO_CTRL, reg_status);

        reg_status = CRYPTO_READ(dev, RK_CRYPTO_CTRL);
        reg_status &= (~RK_CRYPTO_HASH_FLUSH);
        reg_status |= _SBF(0xffff, 16);
        CRYPTO_WRITE(dev, RK_CRYPTO_CTRL, reg_status);

        memset_io(dev->reg + RK_CRYPTO_HASH_DOUT_0, 0, 32);

        CRYPTO_WRITE(dev, RK_CRYPTO_INTENA, RK_CRYPTO_HRDMA_ERR_ENA |
                                            RK_CRYPTO_HRDMA_DONE_ENA);

        CRYPTO_WRITE(dev, RK_CRYPTO_INTSTS, RK_CRYPTO_HRDMA_ERR_INT |
                                            RK_CRYPTO_HRDMA_DONE_INT);

        CRYPTO_WRITE(dev, RK_CRYPTO_HASH_CTRL, rctx->mode |
                                               RK_CRYPTO_HASH_SWAP_DO);

        CRYPTO_WRITE(dev, RK_CRYPTO_CONF, RK_CRYPTO_BYTESWAP_HRFIFO |
                                          RK_CRYPTO_BYTESWAP_BRFIFO |
                                          RK_CRYPTO_BYTESWAP_BTFIFO);

        CRYPTO_WRITE(dev, RK_CRYPTO_HASH_MSG_LEN, req->nbytes);
}

static int rk_ahash_init(struct ahash_request *req)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        struct rk_ahash_ctx *ctx = crypto_ahash_ctx(tfm);

        ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   req->base.complete, req->base.data);

        return crypto_ahash_init(&rctx->fallback_req);
}

static int rk_ahash_update(struct ahash_request *req)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        struct rk_ahash_ctx *ctx = crypto_ahash_ctx(tfm);

        ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   req->base.complete, req->base.data);
        ahash_request_set_crypt(&rctx->fallback_req, req->src, NULL, req->nbytes);

        return crypto_ahash_update(&rctx->fallback_req);
}

static int rk_ahash_final(struct ahash_request *req)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        struct rk_ahash_ctx *ctx = crypto_ahash_ctx(tfm);

        ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   req->base.complete, req->base.data);
        ahash_request_set_crypt(&rctx->fallback_req, NULL, req->result, 0);

        return crypto_ahash_final(&rctx->fallback_req);
}

static int rk_ahash_finup(struct ahash_request *req)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        struct rk_ahash_ctx *ctx = crypto_ahash_ctx(tfm);

        ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   req->base.complete, req->base.data);
        ahash_request_set_crypt(&rctx->fallback_req, req->src, req->result,
                                req->nbytes);

        return crypto_ahash_finup(&rctx->fallback_req);
}

static int rk_ahash_import(struct ahash_request *req, const void *in)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        struct rk_ahash_ctx *ctx = crypto_ahash_ctx(tfm);

        ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   req->base.complete, req->base.data);

        return crypto_ahash_import(&rctx->fallback_req, in);
}

static int rk_ahash_export(struct ahash_request *req, void *out)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
        struct rk_ahash_ctx *ctx = crypto_ahash_ctx(tfm);

        ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback_tfm);
        ahash_request_set_callback(&rctx->fallback_req,
                                   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP,
                                   req->base.complete, req->base.data);

        return crypto_ahash_export(&rctx->fallback_req, out);
}

static int rk_ahash_digest(struct ahash_request *req)
{
        struct rk_ahash_rctx *rctx = ahash_request_ctx(req);
        struct rk_crypto_info *dev;
        struct crypto_engine *engine;

        if (rk_ahash_need_fallback(req))
                return rk_ahash_digest_fb(req);

        if (!req->nbytes)
                return zero_message_process(req);

        dev = get_rk_crypto();

        rctx->dev = dev;
        engine = dev->engine;

        return crypto_transfer_hash_request_to_engine(engine, req);
}

static void crypto_ahash_dma_start(struct rk_crypto_info *dev, struct scatterlist *sg)
{
        CRYPTO_WRITE(dev, RK_CRYPTO_HRDMAS, sg_dma_address(sg));
        CRYPTO_WRITE(dev, RK_CRYPTO_HRDMAL, sg_dma_len(sg) / 4);
        CRYPTO_WRITE(dev, RK_CRYPTO_CTRL, RK_CRYPTO_HASH_START |
                                          (RK_CRYPTO_HASH_START << 16));
}

static int rk_hash_prepare(struct crypto_engine *engine, void *breq)
{
        struct ahash_request *areq = container_of(breq, struct ahash_request, base);
        struct rk_ahash_rctx *rctx = ahash_request_ctx(areq);
        struct rk_crypto_info *rkc = rctx->dev;
        int ret;

        ret = dma_map_sg(rkc->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
        if (ret <= 0)
                return -EINVAL;

        rctx->nrsg = ret;

        return 0;
}

static void rk_hash_unprepare(struct crypto_engine *engine, void *breq)
{
        struct ahash_request *areq = container_of(breq, struct ahash_request, base);
        struct rk_ahash_rctx *rctx = ahash_request_ctx(areq);
        struct rk_crypto_info *rkc = rctx->dev;

        dma_unmap_sg(rkc->dev, areq->src, sg_nents(areq->src), DMA_TO_DEVICE);
}

static int rk_hash_run(struct crypto_engine *engine, void *breq)
{
        struct ahash_request *areq = container_of(breq, struct ahash_request, base);
        struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
        struct rk_ahash_rctx *rctx = ahash_request_ctx(areq);
        struct ahash_alg *alg = crypto_ahash_alg(tfm);
        struct rk_crypto_tmp *algt = container_of(alg, struct rk_crypto_tmp, alg.hash.base);
        struct scatterlist *sg = areq->src;
        struct rk_crypto_info *rkc = rctx->dev;
        int err;
        int i;
        u32 v;

        err = pm_runtime_resume_and_get(rkc->dev);
        if (err)
                return err;

        err = rk_hash_prepare(engine, breq);
        if (err)
                goto theend;

        rctx->mode = 0;

        algt->stat_req++;
        rkc->nreq++;

        switch (crypto_ahash_digestsize(tfm)) {
        case SHA1_DIGEST_SIZE:
                rctx->mode = RK_CRYPTO_HASH_SHA1;
                break;
        case SHA256_DIGEST_SIZE:
                rctx->mode = RK_CRYPTO_HASH_SHA256;
                break;
        case MD5_DIGEST_SIZE:
                rctx->mode = RK_CRYPTO_HASH_MD5;
                break;
        default:
                err =  -EINVAL;
                goto theend;
        }

        rk_ahash_reg_init(areq, rkc);

        while (sg) {
                reinit_completion(&rkc->complete);
                rkc->status = 0;
                crypto_ahash_dma_start(rkc, sg);
                wait_for_completion_interruptible_timeout(&rkc->complete,
                                                          msecs_to_jiffies(2000));
                if (!rkc->status) {
                        dev_err(rkc->dev, "DMA timeout\n");
                        err = -EFAULT;
                        goto theend;
                }
                sg = sg_next(sg);
        }

        /*
         * it will take some time to process date after last dma
         * transmission.
         *
         * waiting time is relative with the last date len,
         * so cannot set a fixed time here.
         * 10us makes system not call here frequently wasting
         * efficiency, and make it response quickly when dma
         * complete.
         */
        readl_poll_timeout(rkc->reg + RK_CRYPTO_HASH_STS, v, v == 0, 10, 1000);

        for (i = 0; i < crypto_ahash_digestsize(tfm) / 4; i++) {
                v = readl(rkc->reg + RK_CRYPTO_HASH_DOUT_0 + i * 4);
                put_unaligned_le32(v, areq->result + i * 4);
        }

theend:
        pm_runtime_put_autosuspend(rkc->dev);

        rk_hash_unprepare(engine, breq);

        local_bh_disable();
        crypto_finalize_hash_request(engine, breq, err);
        local_bh_enable();

        return 0;
}

static int rk_hash_init_tfm(struct crypto_ahash *tfm)
{
        struct rk_ahash_ctx *tctx = crypto_ahash_ctx(tfm);
        const char *alg_name = crypto_ahash_alg_name(tfm);
        struct ahash_alg *alg = crypto_ahash_alg(tfm);
        struct rk_crypto_tmp *algt = container_of(alg, struct rk_crypto_tmp, alg.hash.base);

        /* for fallback */
        tctx->fallback_tfm = crypto_alloc_ahash(alg_name, 0,
                                                CRYPTO_ALG_NEED_FALLBACK);
        if (IS_ERR(tctx->fallback_tfm)) {
                dev_err(algt->dev->dev, "Could not load fallback driver.\n");
                return PTR_ERR(tctx->fallback_tfm);
        }

        crypto_ahash_set_reqsize(tfm,
                                 sizeof(struct rk_ahash_rctx) +
                                 crypto_ahash_reqsize(tctx->fallback_tfm));

        return 0;
}

static void rk_hash_exit_tfm(struct crypto_ahash *tfm)
{
        struct rk_ahash_ctx *tctx = crypto_ahash_ctx(tfm);

        crypto_free_ahash(tctx->fallback_tfm);
}

struct rk_crypto_tmp rk_ahash_sha1 = {
        .type = CRYPTO_ALG_TYPE_AHASH,
        .alg.hash.base = {
                .init = rk_ahash_init,
                .update = rk_ahash_update,
                .final = rk_ahash_final,
                .finup = rk_ahash_finup,
                .export = rk_ahash_export,
                .import = rk_ahash_import,
                .digest = rk_ahash_digest,
                .init_tfm = rk_hash_init_tfm,
                .exit_tfm = rk_hash_exit_tfm,
                .halg = {
                         .digestsize = SHA1_DIGEST_SIZE,
                         .statesize = sizeof(struct sha1_state),
                         .base = {
                                  .cra_name = "sha1",
                                  .cra_driver_name = "rk-sha1",
                                  .cra_priority = 300,
                                  .cra_flags = CRYPTO_ALG_ASYNC |
                                               CRYPTO_ALG_NEED_FALLBACK,
                                  .cra_blocksize = SHA1_BLOCK_SIZE,
                                  .cra_ctxsize = sizeof(struct rk_ahash_ctx),
                                  .cra_module = THIS_MODULE,
                        }
                }
        },
        .alg.hash.op = {
                .do_one_request = rk_hash_run,
        },
};

struct rk_crypto_tmp rk_ahash_sha256 = {
        .type = CRYPTO_ALG_TYPE_AHASH,
        .alg.hash.base = {
                .init = rk_ahash_init,
                .update = rk_ahash_update,
                .final = rk_ahash_final,
                .finup = rk_ahash_finup,
                .export = rk_ahash_export,
                .import = rk_ahash_import,
                .digest = rk_ahash_digest,
                .init_tfm = rk_hash_init_tfm,
                .exit_tfm = rk_hash_exit_tfm,
                .halg = {
                         .digestsize = SHA256_DIGEST_SIZE,
                         .statesize = sizeof(struct sha256_state),
                         .base = {
                                  .cra_name = "sha256",
                                  .cra_driver_name = "rk-sha256",
                                  .cra_priority = 300,
                                  .cra_flags = CRYPTO_ALG_ASYNC |
                                               CRYPTO_ALG_NEED_FALLBACK,
                                  .cra_blocksize = SHA256_BLOCK_SIZE,
                                  .cra_ctxsize = sizeof(struct rk_ahash_ctx),
                                  .cra_module = THIS_MODULE,
                        }
                }
        },
        .alg.hash.op = {
                .do_one_request = rk_hash_run,
        },
};

struct rk_crypto_tmp rk_ahash_md5 = {
        .type = CRYPTO_ALG_TYPE_AHASH,
        .alg.hash.base = {
                .init = rk_ahash_init,
                .update = rk_ahash_update,
                .final = rk_ahash_final,
                .finup = rk_ahash_finup,
                .export = rk_ahash_export,
                .import = rk_ahash_import,
                .digest = rk_ahash_digest,
                .init_tfm = rk_hash_init_tfm,
                .exit_tfm = rk_hash_exit_tfm,
                .halg = {
                         .digestsize = MD5_DIGEST_SIZE,
                         .statesize = sizeof(struct md5_state),
                         .base = {
                                  .cra_name = "md5",
                                  .cra_driver_name = "rk-md5",
                                  .cra_priority = 300,
                                  .cra_flags = CRYPTO_ALG_ASYNC |
                                               CRYPTO_ALG_NEED_FALLBACK,
                                  .cra_blocksize = SHA1_BLOCK_SIZE,
                                  .cra_ctxsize = sizeof(struct rk_ahash_ctx),
                                  .cra_module = THIS_MODULE,
                        }
                }
        },
        .alg.hash.op = {
                .do_one_request = rk_hash_run,
        },
};