root/drivers/crypto/amlogic/amlogic-gxl-core.c
// SPDX-License-Identifier: GPL-2.0
/*
 * amlgoic-core.c - hardware cryptographic offloader for Amlogic GXL SoC
 *
 * Copyright (C) 2018-2019 Corentin Labbe <clabbe@baylibre.com>
 *
 * Core file which registers crypto algorithms supported by the hardware.
 */

#include <crypto/engine.h>
#include <crypto/internal/skcipher.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>

#include "amlogic-gxl.h"

static irqreturn_t meson_irq_handler(int irq, void *data)
{
        struct meson_dev *mc = (struct meson_dev *)data;
        int flow;
        u32 p;

        for (flow = 0; flow < MAXFLOW; flow++) {
                if (mc->irqs[flow] == irq) {
                        p = readl(mc->base + ((0x04 + flow) << 2));
                        if (p) {
                                writel_relaxed(0xF, mc->base + ((0x4 + flow) << 2));
                                mc->chanlist[flow].status = 1;
                                complete(&mc->chanlist[flow].complete);
                                return IRQ_HANDLED;
                        }
                        dev_err(mc->dev, "%s %d Got irq for flow %d but ctrl is empty\n", __func__, irq, flow);
                }
        }

        dev_err(mc->dev, "%s %d from unknown irq\n", __func__, irq);
        return IRQ_HANDLED;
}

static struct meson_alg_template mc_algs[] = {
{
        .type = CRYPTO_ALG_TYPE_SKCIPHER,
        .blockmode = MESON_OPMODE_CBC,
        .alg.skcipher.base = {
                .base = {
                        .cra_name = "cbc(aes)",
                        .cra_driver_name = "cbc-aes-gxl",
                        .cra_priority = 400,
                        .cra_blocksize = AES_BLOCK_SIZE,
                        .cra_flags = CRYPTO_ALG_TYPE_SKCIPHER |
                                CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY |
                                CRYPTO_ALG_NEED_FALLBACK,
                        .cra_ctxsize = sizeof(struct meson_cipher_tfm_ctx),
                        .cra_module = THIS_MODULE,
                        .cra_alignmask = 0xf,
                        .cra_init = meson_cipher_init,
                        .cra_exit = meson_cipher_exit,
                },
                .min_keysize    = AES_MIN_KEY_SIZE,
                .max_keysize    = AES_MAX_KEY_SIZE,
                .ivsize         = AES_BLOCK_SIZE,
                .setkey         = meson_aes_setkey,
                .encrypt        = meson_skencrypt,
                .decrypt        = meson_skdecrypt,
        },
        .alg.skcipher.op = {
                .do_one_request = meson_handle_cipher_request,
        },
},
{
        .type = CRYPTO_ALG_TYPE_SKCIPHER,
        .blockmode = MESON_OPMODE_ECB,
        .alg.skcipher.base = {
                .base = {
                        .cra_name = "ecb(aes)",
                        .cra_driver_name = "ecb-aes-gxl",
                        .cra_priority = 400,
                        .cra_blocksize = AES_BLOCK_SIZE,
                        .cra_flags = CRYPTO_ALG_TYPE_SKCIPHER |
                                CRYPTO_ALG_ASYNC | CRYPTO_ALG_ALLOCATES_MEMORY |
                                CRYPTO_ALG_NEED_FALLBACK,
                        .cra_ctxsize = sizeof(struct meson_cipher_tfm_ctx),
                        .cra_module = THIS_MODULE,
                        .cra_alignmask = 0xf,
                        .cra_init = meson_cipher_init,
                        .cra_exit = meson_cipher_exit,
                },
                .min_keysize    = AES_MIN_KEY_SIZE,
                .max_keysize    = AES_MAX_KEY_SIZE,
                .setkey         = meson_aes_setkey,
                .encrypt        = meson_skencrypt,
                .decrypt        = meson_skdecrypt,
        },
        .alg.skcipher.op = {
                .do_one_request = meson_handle_cipher_request,
        },
},
};

static int meson_debugfs_show(struct seq_file *seq, void *v)
{
        struct meson_dev *mc __maybe_unused = seq->private;
        int i;

        for (i = 0; i < MAXFLOW; i++)
                seq_printf(seq, "Channel %d: nreq %lu\n", i,
#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
                           mc->chanlist[i].stat_req);
#else
                           0ul);
#endif

        for (i = 0; i < ARRAY_SIZE(mc_algs); i++) {
                switch (mc_algs[i].type) {
                case CRYPTO_ALG_TYPE_SKCIPHER:
                        seq_printf(seq, "%s %s %lu %lu\n",
                                   mc_algs[i].alg.skcipher.base.base.cra_driver_name,
                                   mc_algs[i].alg.skcipher.base.base.cra_name,
#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
                                   mc_algs[i].stat_req, mc_algs[i].stat_fb);
#else
                                   0ul, 0ul);
#endif
                        break;
                }
        }
        return 0;
}
DEFINE_SHOW_ATTRIBUTE(meson_debugfs);

static void meson_free_chanlist(struct meson_dev *mc, int i)
{
        while (i >= 0) {
                crypto_engine_exit(mc->chanlist[i].engine);
                if (mc->chanlist[i].tl)
                        dma_free_coherent(mc->dev, sizeof(struct meson_desc) * MAXDESC,
                                          mc->chanlist[i].tl,
                                          mc->chanlist[i].t_phy);
                i--;
        }
}

/*
 * Allocate the channel list structure
 */
static int meson_allocate_chanlist(struct meson_dev *mc)
{
        int i, err;

        mc->chanlist = devm_kcalloc(mc->dev, MAXFLOW,
                                    sizeof(struct meson_flow), GFP_KERNEL);
        if (!mc->chanlist)
                return -ENOMEM;

        for (i = 0; i < MAXFLOW; i++) {
                init_completion(&mc->chanlist[i].complete);

                mc->chanlist[i].engine = crypto_engine_alloc_init(mc->dev, true);
                if (!mc->chanlist[i].engine) {
                        dev_err(mc->dev, "Cannot allocate engine\n");
                        i--;
                        err = -ENOMEM;
                        goto error_engine;
                }
                err = crypto_engine_start(mc->chanlist[i].engine);
                if (err) {
                        dev_err(mc->dev, "Cannot start engine\n");
                        goto error_engine;
                }
                mc->chanlist[i].tl = dma_alloc_coherent(mc->dev,
                                                        sizeof(struct meson_desc) * MAXDESC,
                                                        &mc->chanlist[i].t_phy,
                                                        GFP_KERNEL);
                if (!mc->chanlist[i].tl) {
                        err = -ENOMEM;
                        goto error_engine;
                }
        }
        return 0;
error_engine:
        meson_free_chanlist(mc, i);
        return err;
}

static int meson_register_algs(struct meson_dev *mc)
{
        int err, i;

        for (i = 0; i < ARRAY_SIZE(mc_algs); i++) {
                mc_algs[i].mc = mc;
                switch (mc_algs[i].type) {
                case CRYPTO_ALG_TYPE_SKCIPHER:
                        err = crypto_engine_register_skcipher(&mc_algs[i].alg.skcipher);
                        if (err) {
                                dev_err(mc->dev, "Fail to register %s\n",
                                        mc_algs[i].alg.skcipher.base.base.cra_name);
                                mc_algs[i].mc = NULL;
                                return err;
                        }
                        break;
                }
        }

        return 0;
}

static void meson_unregister_algs(struct meson_dev *mc)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(mc_algs); i++) {
                if (!mc_algs[i].mc)
                        continue;
                switch (mc_algs[i].type) {
                case CRYPTO_ALG_TYPE_SKCIPHER:
                        crypto_engine_unregister_skcipher(&mc_algs[i].alg.skcipher);
                        break;
                }
        }
}

static int meson_crypto_probe(struct platform_device *pdev)
{
        struct meson_dev *mc;
        int err, i;

        mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
        if (!mc)
                return -ENOMEM;

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

        mc->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(mc->base))
                return PTR_ERR(mc->base);

        mc->busclk = devm_clk_get(&pdev->dev, "blkmv");
        if (IS_ERR(mc->busclk)) {
                err = PTR_ERR(mc->busclk);
                dev_err(&pdev->dev, "Cannot get core clock err=%d\n", err);
                return err;
        }

        for (i = 0; i < MAXFLOW; i++) {
                mc->irqs[i] = platform_get_irq(pdev, i);
                if (mc->irqs[i] < 0)
                        return mc->irqs[i];

                err = devm_request_irq(&pdev->dev, mc->irqs[i], meson_irq_handler, 0,
                                       "gxl-crypto", mc);
                if (err < 0) {
                        dev_err(mc->dev, "Cannot request IRQ for flow %d\n", i);
                        return err;
                }
        }

        err = clk_prepare_enable(mc->busclk);
        if (err != 0) {
                dev_err(&pdev->dev, "Cannot prepare_enable busclk\n");
                return err;
        }

        err = meson_allocate_chanlist(mc);
        if (err)
                goto error_flow;

        err = meson_register_algs(mc);
        if (err)
                goto error_alg;

        if (IS_ENABLED(CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG)) {
                struct dentry *dbgfs_dir;

                dbgfs_dir = debugfs_create_dir("gxl-crypto", NULL);
                debugfs_create_file("stats", 0444, dbgfs_dir, mc, &meson_debugfs_fops);

#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
                mc->dbgfs_dir = dbgfs_dir;
#endif
        }

        return 0;
error_alg:
        meson_unregister_algs(mc);
error_flow:
        meson_free_chanlist(mc, MAXFLOW - 1);
        clk_disable_unprepare(mc->busclk);
        return err;
}

static void meson_crypto_remove(struct platform_device *pdev)
{
        struct meson_dev *mc = platform_get_drvdata(pdev);

#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
        debugfs_remove_recursive(mc->dbgfs_dir);
#endif

        meson_unregister_algs(mc);

        meson_free_chanlist(mc, MAXFLOW - 1);

        clk_disable_unprepare(mc->busclk);
}

static const struct of_device_id meson_crypto_of_match_table[] = {
        { .compatible = "amlogic,gxl-crypto", },
        {}
};
MODULE_DEVICE_TABLE(of, meson_crypto_of_match_table);

static struct platform_driver meson_crypto_driver = {
        .probe           = meson_crypto_probe,
        .remove          = meson_crypto_remove,
        .driver          = {
                .name              = "gxl-crypto",
                .of_match_table = meson_crypto_of_match_table,
        },
};

module_platform_driver(meson_crypto_driver);

MODULE_DESCRIPTION("Amlogic GXL cryptographic offloader");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Corentin Labbe <clabbe@baylibre.com>");