root/drivers/crypto/rockchip/rk3288_crypto.c
// 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 "rk3288_crypto.h"
#include <crypto/engine.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/skcipher.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/reset.h>
#include <linux/spinlock.h>

static struct rockchip_ip rocklist = {
        .dev_list = LIST_HEAD_INIT(rocklist.dev_list),
        .lock = __SPIN_LOCK_UNLOCKED(rocklist.lock),
};

struct rk_crypto_info *get_rk_crypto(void)
{
        struct rk_crypto_info *first;

        spin_lock(&rocklist.lock);
        first = list_first_entry_or_null(&rocklist.dev_list,
                                         struct rk_crypto_info, list);
        list_rotate_left(&rocklist.dev_list);
        spin_unlock(&rocklist.lock);
        return first;
}

static const struct rk_variant rk3288_variant = {
        .num_clks = 4,
        .rkclks = {
                { "sclk", 150000000},
        }
};

static const struct rk_variant rk3328_variant = {
        .num_clks = 3,
};

static const struct rk_variant rk3399_variant = {
        .num_clks = 3,
};

static int rk_crypto_get_clks(struct rk_crypto_info *dev)
{
        int i, j, err;
        unsigned long cr;

        dev->num_clks = devm_clk_bulk_get_all(dev->dev, &dev->clks);
        if (dev->num_clks < dev->variant->num_clks) {
                dev_err(dev->dev, "Missing clocks, got %d instead of %d\n",
                        dev->num_clks, dev->variant->num_clks);
                return -EINVAL;
        }

        for (i = 0; i < dev->num_clks; i++) {
                cr = clk_get_rate(dev->clks[i].clk);
                for (j = 0; j < ARRAY_SIZE(dev->variant->rkclks); j++) {
                        if (dev->variant->rkclks[j].max == 0)
                                continue;
                        if (strcmp(dev->variant->rkclks[j].name, dev->clks[i].id))
                                continue;
                        if (cr > dev->variant->rkclks[j].max) {
                                err = clk_set_rate(dev->clks[i].clk,
                                                   dev->variant->rkclks[j].max);
                                if (err)
                                        dev_err(dev->dev, "Fail downclocking %s from %lu to %lu\n",
                                                dev->variant->rkclks[j].name, cr,
                                                dev->variant->rkclks[j].max);
                                else
                                        dev_info(dev->dev, "Downclocking %s from %lu to %lu\n",
                                                 dev->variant->rkclks[j].name, cr,
                                                 dev->variant->rkclks[j].max);
                        }
                }
        }
        return 0;
}

static int rk_crypto_enable_clk(struct rk_crypto_info *dev)
{
        int err;

        err = clk_bulk_prepare_enable(dev->num_clks, dev->clks);
        if (err)
                dev_err(dev->dev, "Could not enable clock clks\n");

        return err;
}

static void rk_crypto_disable_clk(struct rk_crypto_info *dev)
{
        clk_bulk_disable_unprepare(dev->num_clks, dev->clks);
}

/*
 * Power management strategy: The device is suspended until a request
 * is handled. For avoiding suspend/resume yoyo, the autosuspend is set to 2s.
 */
static int rk_crypto_pm_suspend(struct device *dev)
{
        struct rk_crypto_info *rkdev = dev_get_drvdata(dev);

        rk_crypto_disable_clk(rkdev);
        reset_control_assert(rkdev->rst);

        return 0;
}

static int rk_crypto_pm_resume(struct device *dev)
{
        struct rk_crypto_info *rkdev = dev_get_drvdata(dev);
        int ret;

        ret = rk_crypto_enable_clk(rkdev);
        if (ret)
                return ret;

        reset_control_deassert(rkdev->rst);
        return 0;

}

static const struct dev_pm_ops rk_crypto_pm_ops = {
        SET_RUNTIME_PM_OPS(rk_crypto_pm_suspend, rk_crypto_pm_resume, NULL)
};

static int rk_crypto_pm_init(struct rk_crypto_info *rkdev)
{
        int err;

        pm_runtime_use_autosuspend(rkdev->dev);
        pm_runtime_set_autosuspend_delay(rkdev->dev, 2000);

        err = pm_runtime_set_suspended(rkdev->dev);
        if (err)
                return err;
        pm_runtime_enable(rkdev->dev);
        return err;
}

static void rk_crypto_pm_exit(struct rk_crypto_info *rkdev)
{
        pm_runtime_disable(rkdev->dev);
}

static irqreturn_t rk_crypto_irq_handle(int irq, void *dev_id)
{
        struct rk_crypto_info *dev  = platform_get_drvdata(dev_id);
        u32 interrupt_status;

        interrupt_status = CRYPTO_READ(dev, RK_CRYPTO_INTSTS);
        CRYPTO_WRITE(dev, RK_CRYPTO_INTSTS, interrupt_status);

        dev->status = 1;
        if (interrupt_status & 0x0a) {
                dev_warn(dev->dev, "DMA Error\n");
                dev->status = 0;
        }
        complete(&dev->complete);

        return IRQ_HANDLED;
}

static struct rk_crypto_tmp *rk_cipher_algs[] = {
        &rk_ecb_aes_alg,
        &rk_cbc_aes_alg,
        &rk_ecb_des_alg,
        &rk_cbc_des_alg,
        &rk_ecb_des3_ede_alg,
        &rk_cbc_des3_ede_alg,
        &rk_ahash_sha1,
        &rk_ahash_sha256,
        &rk_ahash_md5,
};

static int rk_crypto_debugfs_show(struct seq_file *seq, void *v)
{
        struct rk_crypto_info *dd;
        unsigned int i;

        spin_lock(&rocklist.lock);
        list_for_each_entry(dd, &rocklist.dev_list, list) {
                seq_printf(seq, "%s %s requests: %lu\n",
                           dev_driver_string(dd->dev), dev_name(dd->dev),
                           dd->nreq);
        }
        spin_unlock(&rocklist.lock);

        for (i = 0; i < ARRAY_SIZE(rk_cipher_algs); i++) {
                if (!rk_cipher_algs[i]->dev)
                        continue;
                switch (rk_cipher_algs[i]->type) {
                case CRYPTO_ALG_TYPE_SKCIPHER:
                        seq_printf(seq, "%s %s reqs=%lu fallback=%lu\n",
                                   rk_cipher_algs[i]->alg.skcipher.base.base.cra_driver_name,
                                   rk_cipher_algs[i]->alg.skcipher.base.base.cra_name,
                                   rk_cipher_algs[i]->stat_req, rk_cipher_algs[i]->stat_fb);
                        seq_printf(seq, "\tfallback due to length: %lu\n",
                                   rk_cipher_algs[i]->stat_fb_len);
                        seq_printf(seq, "\tfallback due to alignment: %lu\n",
                                   rk_cipher_algs[i]->stat_fb_align);
                        seq_printf(seq, "\tfallback due to SGs: %lu\n",
                                   rk_cipher_algs[i]->stat_fb_sgdiff);
                        break;
                case CRYPTO_ALG_TYPE_AHASH:
                        seq_printf(seq, "%s %s reqs=%lu fallback=%lu\n",
                                   rk_cipher_algs[i]->alg.hash.base.halg.base.cra_driver_name,
                                   rk_cipher_algs[i]->alg.hash.base.halg.base.cra_name,
                                   rk_cipher_algs[i]->stat_req, rk_cipher_algs[i]->stat_fb);
                        break;
                }
        }
        return 0;
}

DEFINE_SHOW_ATTRIBUTE(rk_crypto_debugfs);

static void register_debugfs(struct rk_crypto_info *crypto_info)
{
        struct dentry *dbgfs_dir __maybe_unused;
        struct dentry *dbgfs_stats __maybe_unused;

        /* Ignore error of debugfs */
        dbgfs_dir = debugfs_create_dir("rk3288_crypto", NULL);
        dbgfs_stats = debugfs_create_file("stats", 0444, dbgfs_dir, &rocklist,
                                          &rk_crypto_debugfs_fops);

#ifdef CONFIG_CRYPTO_DEV_ROCKCHIP_DEBUG
        rocklist.dbgfs_dir = dbgfs_dir;
        rocklist.dbgfs_stats = dbgfs_stats;
#endif
}

static int rk_crypto_register(struct rk_crypto_info *crypto_info)
{
        unsigned int i, k;
        int err = 0;

        for (i = 0; i < ARRAY_SIZE(rk_cipher_algs); i++) {
                rk_cipher_algs[i]->dev = crypto_info;
                switch (rk_cipher_algs[i]->type) {
                case CRYPTO_ALG_TYPE_SKCIPHER:
                        dev_info(crypto_info->dev, "Register %s as %s\n",
                                 rk_cipher_algs[i]->alg.skcipher.base.base.cra_name,
                                 rk_cipher_algs[i]->alg.skcipher.base.base.cra_driver_name);
                        err = crypto_engine_register_skcipher(&rk_cipher_algs[i]->alg.skcipher);
                        break;
                case CRYPTO_ALG_TYPE_AHASH:
                        dev_info(crypto_info->dev, "Register %s as %s\n",
                                 rk_cipher_algs[i]->alg.hash.base.halg.base.cra_name,
                                 rk_cipher_algs[i]->alg.hash.base.halg.base.cra_driver_name);
                        err = crypto_engine_register_ahash(&rk_cipher_algs[i]->alg.hash);
                        break;
                default:
                        dev_err(crypto_info->dev, "unknown algorithm\n");
                }
                if (err)
                        goto err_cipher_algs;
        }
        return 0;

err_cipher_algs:
        for (k = 0; k < i; k++) {
                if (rk_cipher_algs[i]->type == CRYPTO_ALG_TYPE_SKCIPHER)
                        crypto_engine_unregister_skcipher(&rk_cipher_algs[k]->alg.skcipher);
                else
                        crypto_engine_unregister_ahash(&rk_cipher_algs[i]->alg.hash);
        }
        return err;
}

static void rk_crypto_unregister(void)
{
        unsigned int i;

        for (i = 0; i < ARRAY_SIZE(rk_cipher_algs); i++) {
                if (rk_cipher_algs[i]->type == CRYPTO_ALG_TYPE_SKCIPHER)
                        crypto_engine_unregister_skcipher(&rk_cipher_algs[i]->alg.skcipher);
                else
                        crypto_engine_unregister_ahash(&rk_cipher_algs[i]->alg.hash);
        }
}

static const struct of_device_id crypto_of_id_table[] = {
        { .compatible = "rockchip,rk3288-crypto",
          .data = &rk3288_variant,
        },
        { .compatible = "rockchip,rk3328-crypto",
          .data = &rk3328_variant,
        },
        { .compatible = "rockchip,rk3399-crypto",
          .data = &rk3399_variant,
        },
        {}
};
MODULE_DEVICE_TABLE(of, crypto_of_id_table);

static int rk_crypto_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct rk_crypto_info *crypto_info, *first;
        int err = 0;

        crypto_info = devm_kzalloc(&pdev->dev,
                                   sizeof(*crypto_info), GFP_KERNEL);
        if (!crypto_info) {
                err = -ENOMEM;
                goto err_crypto;
        }

        crypto_info->dev = &pdev->dev;
        platform_set_drvdata(pdev, crypto_info);

        crypto_info->variant = of_device_get_match_data(&pdev->dev);
        if (!crypto_info->variant) {
                dev_err(&pdev->dev, "Missing variant\n");
                return -EINVAL;
        }

        crypto_info->rst = devm_reset_control_array_get_exclusive(dev);
        if (IS_ERR(crypto_info->rst)) {
                err = PTR_ERR(crypto_info->rst);
                goto err_crypto;
        }

        reset_control_assert(crypto_info->rst);
        usleep_range(10, 20);
        reset_control_deassert(crypto_info->rst);

        crypto_info->reg = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(crypto_info->reg)) {
                err = PTR_ERR(crypto_info->reg);
                goto err_crypto;
        }

        err = rk_crypto_get_clks(crypto_info);
        if (err)
                goto err_crypto;

        crypto_info->irq = platform_get_irq(pdev, 0);
        if (crypto_info->irq < 0) {
                err = crypto_info->irq;
                goto err_crypto;
        }

        err = devm_request_irq(&pdev->dev, crypto_info->irq,
                               rk_crypto_irq_handle, IRQF_SHARED,
                               "rk-crypto", pdev);

        if (err) {
                dev_err(&pdev->dev, "irq request failed.\n");
                goto err_crypto;
        }

        crypto_info->engine = crypto_engine_alloc_init(&pdev->dev, true);
        if (!crypto_info->engine) {
                err = -ENOMEM;
                goto err_crypto;
        }

        crypto_engine_start(crypto_info->engine);
        init_completion(&crypto_info->complete);

        err = rk_crypto_pm_init(crypto_info);
        if (err)
                goto err_pm;

        spin_lock(&rocklist.lock);
        first = list_first_entry_or_null(&rocklist.dev_list,
                                         struct rk_crypto_info, list);
        list_add_tail(&crypto_info->list, &rocklist.dev_list);
        spin_unlock(&rocklist.lock);

        if (!first) {
                err = rk_crypto_register(crypto_info);
                if (err) {
                        dev_err(dev, "Fail to register crypto algorithms");
                        goto err_register_alg;
                }

                register_debugfs(crypto_info);
        }

        return 0;

err_register_alg:
        rk_crypto_pm_exit(crypto_info);
err_pm:
        crypto_engine_exit(crypto_info->engine);
err_crypto:
        dev_err(dev, "Crypto Accelerator not successfully registered\n");
        return err;
}

static void rk_crypto_remove(struct platform_device *pdev)
{
        struct rk_crypto_info *crypto_tmp = platform_get_drvdata(pdev);
        struct rk_crypto_info *first;

        spin_lock_bh(&rocklist.lock);
        list_del(&crypto_tmp->list);
        first = list_first_entry_or_null(&rocklist.dev_list,
                                         struct rk_crypto_info, list);
        spin_unlock_bh(&rocklist.lock);

        if (!first) {
#ifdef CONFIG_CRYPTO_DEV_ROCKCHIP_DEBUG
                debugfs_remove_recursive(rocklist.dbgfs_dir);
#endif
                rk_crypto_unregister();
        }
        rk_crypto_pm_exit(crypto_tmp);
        crypto_engine_exit(crypto_tmp->engine);
}

static struct platform_driver crypto_driver = {
        .probe          = rk_crypto_probe,
        .remove         = rk_crypto_remove,
        .driver         = {
                .name   = "rk3288-crypto",
                .pm             = &rk_crypto_pm_ops,
                .of_match_table = crypto_of_id_table,
        },
};

module_platform_driver(crypto_driver);

MODULE_AUTHOR("Zain Wang <zain.wang@rock-chips.com>");
MODULE_DESCRIPTION("Support for Rockchip's cryptographic engine");
MODULE_LICENSE("GPL");