crypto: amlogic - Add crypto accelerator for amlogic GXL

This patch adds support for the amlogic GXL cryptographic offloader present
on GXL SoCs.

This driver supports AES cipher in CBC/ECB mode.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/Kconfig

@@ -808,4 +808,6 @@ config CRYPTO_DEV_CCREE
 
 source "drivers/crypto/hisilicon/Kconfig"
 
+source "drivers/crypto/amlogic/Kconfig"
+
 endif # CRYPTO_HW

drivers/crypto/Makefile

@@ -48,3 +48,4 @@ obj-$(CONFIG_CRYPTO_DEV_BCM_SPU) += bcm/
 obj-$(CONFIG_CRYPTO_DEV_SAFEXCEL) += inside-secure/
 obj-$(CONFIG_CRYPTO_DEV_ARTPEC6) += axis/
 obj-y += hisilicon/
+obj-$(CONFIG_CRYPTO_DEV_AMLOGIC_GXL) += amlogic/

drivers/crypto/amlogic/Kconfig

+config CRYPTO_DEV_AMLOGIC_GXL
+	tristate "Support for amlogic cryptographic offloader"
+	default y if ARCH_MESON
+	select CRYPTO_BLKCIPHER
+	select CRYPTO_ENGINE
+	select CRYPTO_ECB
+	select CRYPTO_CBC
+	select CRYPTO_AES
+	help
+	  Select y here to have support for the cryptographic offloader
+	  available on Amlogic GXL SoC.
+	  This hardware handles AES ciphers in ECB/CBC mode.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called amlogic-gxl-crypto.
+
+config CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	bool "Enable amlogic stats"
+	depends on CRYPTO_DEV_AMLOGIC_GXL
+	depends on DEBUG_FS
+	help
+	  Say y to enable amlogic-crypto debug stats.
+	  This will create /sys/kernel/debug/gxl-crypto/stats for displaying
+	  the number of requests per flow and per algorithm.

drivers/crypto/amlogic/Makefile

+obj-$(CONFIG_CRYPTO_DEV_AMLOGIC_GXL) += amlogic-gxl-crypto.o
+amlogic-gxl-crypto-y := amlogic-gxl-core.o amlogic-gxl-cipher.o

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 <linux/clk.h>
+#include <linux/crypto.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <crypto/internal/skcipher.h>
+#include <linux/dma-mapping.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 = {
+			.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_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,
+	}
+},
+{
+	.type = CRYPTO_ALG_TYPE_SKCIPHER,
+	.blockmode = MESON_OPMODE_ECB,
+	.alg.skcipher = {
+		.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_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,
+	}
+},
+};
+
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+static int meson_dbgfs_read(struct seq_file *seq, void *v)
+{
+	struct meson_dev *mc = seq->private;
+	int i;
+
+	for (i = 0; i < MAXFLOW; i++)
+		seq_printf(seq, "Channel %d: nreq %lu\n", i, mc->chanlist[i].stat_req);
+
+	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.cra_driver_name,
+				   mc_algs[i].alg.skcipher.base.cra_name,
+				   mc_algs[i].stat_req, mc_algs[i].stat_fb);
+			break;
+		}
+	}
+	return 0;
+}
+
+static int meson_dbgfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, meson_dbgfs_read, inode->i_private);
+}
+
+static const struct file_operations meson_debugfs_fops = {
+	.owner = THIS_MODULE,
+	.open = meson_dbgfs_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+#endif
+
+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--;
+			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_register_skcipher(&mc_algs[i].alg.skcipher);
+			if (err) {
+				dev_err(mc->dev, "Fail to register %s\n",
+					mc_algs[i].alg.skcipher.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_unregister_skcipher(&mc_algs[i].alg.skcipher);
+			break;
+		}
+	}
+}
+
+static int meson_crypto_probe(struct platform_device *pdev)
+{
+	struct meson_dev *mc;
+	int err, i;
+
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	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)) {
+		err = PTR_ERR(mc->base);
+		dev_err(&pdev->dev, "Cannot request MMIO err=%d\n", err);
+		return err;
+	}
+	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;
+	}
+
+	mc->irqs = devm_kcalloc(mc->dev, MAXFLOW, sizeof(int), GFP_KERNEL);
+	for (i = 0; i < MAXFLOW; i++) {
+		mc->irqs[i] = platform_get_irq(pdev, i);
+		if (mc->irqs[i] < 0) {
+			dev_err(mc->dev, "Cannot get IRQ for flow %d\n", i);
+			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;
+
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	mc->dbgfs_dir = debugfs_create_dir("gxl-crypto", NULL);
+	debugfs_create_file("stats", 0444, mc->dbgfs_dir, mc, &meson_debugfs_fops);
+#endif
+
+	return 0;
+error_alg:
+	meson_unregister_algs(mc);
+error_flow:
+	meson_free_chanlist(mc, MAXFLOW);
+	clk_disable_unprepare(mc->busclk);
+	return err;
+}
+
+static int 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);
+
+	clk_disable_unprepare(mc->busclk);
+	return 0;
+}
+
+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>");

drivers/crypto/amlogic/amlogic-gxl.h

+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * amlogic.h - hardware cryptographic offloader for Amlogic SoC
+ *
+ * Copyright (C) 2018-2019 Corentin LABBE <clabbe@baylibre.com>
+ */
+#include <crypto/aes.h>
+#include <crypto/engine.h>
+#include <crypto/skcipher.h>
+#include <linux/debugfs.h>
+#include <linux/crypto.h>
+#include <linux/scatterlist.h>
+
+#define MODE_KEY 1
+#define MODE_AES_128 0x8
+#define MODE_AES_192 0x9
+#define MODE_AES_256 0xa
+
+#define MESON_DECRYPT 0
+#define MESON_ENCRYPT 1
+
+#define MESON_OPMODE_ECB 0
+#define MESON_OPMODE_CBC 1
+
+#define MAXFLOW 2
+
+#define MAXDESC 64
+
+/*
+ * struct meson_desc - Descriptor for DMA operations
+ * Note that without datasheet, some are unknown
+ * @len:	length of data to operate
+ * @irq:	Ignored by hardware
+ * @eoc:	End of descriptor
+ * @loop:	Unknown
+ * @mode:	Type of algorithm (AES, SHA)
+ * @begin:	Unknown
+ * @end:	Unknown
+ * @op_mode:	Blockmode (CBC, ECB)
+ * @block:	Unknown
+ * @error:	Unknown
+ * @owner:	owner of the descriptor, 1 own by HW
+ * @t_src:	Physical address of data to read
+ * @t_dst:	Physical address of data to write
+ */
+struct meson_desc {
+	union {
+		u32 t_status;
+		struct {
+			u32 len:17;
+			u32 irq:1;
+			u32 eoc:1;
+			u32 loop:1;
+			u32 mode:4;
+			u32 begin:1;
+			u32 end:1;
+			u32 op_mode:2;
+			u32 enc:1;
+			u32 block:1;
+			u32 error:1;
+			u32 owner:1;
+		};
+	};
+	u32 t_src;
+	u32 t_dst;
+};
+
+/*
+ * struct meson_flow - Information used by each flow
+ * @engine:	ptr to the crypto_engine for this flow
+ * @keylen:	keylen for this flow operation
+ * @complete:	completion for the current task on this flow
+ * @status:	set to 1 by interrupt if task is done
+ * @t_phy:	Physical address of task
+ * @tl:		pointer to the current ce_task for this flow
+ * @stat_req:	number of request done by this flow
+ */
+struct meson_flow {
+	struct crypto_engine *engine;
+	struct completion complete;
+	int status;
+	unsigned int keylen;
+	dma_addr_t t_phy;
+	struct meson_desc *tl;
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	unsigned long stat_req;
+#endif
+};
+
+/*
+ * struct meson_dev - main container for all this driver information
+ * @base:	base address of amlogic-crypto
+ * @busclk:	bus clock for amlogic-crypto
+ * @dev:	the platform device
+ * @chanlist:	array of all flow
+ * @flow:	flow to use in next request
+ * @irqs:	IRQ numbers for amlogic-crypto
+ * @dbgfs_dir:	Debugfs dentry for statistic directory
+ * @dbgfs_stats: Debugfs dentry for statistic counters
+ */
+struct meson_dev {
+	void __iomem *base;
+	struct clk *busclk;
+	struct device *dev;
+	struct meson_flow *chanlist;
+	atomic_t flow;
+	int *irqs;
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	struct dentry *dbgfs_dir;
+#endif
+};
+
+/*
+ * struct meson_cipher_req_ctx - context for a skcipher request
+ * @op_dir:	direction (encrypt vs decrypt) for this request
+ * @flow:	the flow to use for this request
+ */
+struct meson_cipher_req_ctx {
+	u32 op_dir;
+	int flow;
+};
+
+/*
+ * struct meson_cipher_tfm_ctx - context for a skcipher TFM
+ * @enginectx:		crypto_engine used by this TFM
+ * @key:		pointer to key data
+ * @keylen:		len of the key
+ * @keymode:		The keymode(type and size of key) associated with this TFM
+ * @mc:			pointer to the private data of driver handling this TFM
+ * @fallback_tfm:	pointer to the fallback TFM
+ */
+struct meson_cipher_tfm_ctx {
+	struct crypto_engine_ctx enginectx;
+	u32 *key;
+	u32 keylen;
+	u32 keymode;
+	struct meson_dev *mc;
+	struct crypto_sync_skcipher *fallback_tfm;
+};
+
+/*
+ * struct meson_alg_template - crypto_alg template
+ * @type:		the CRYPTO_ALG_TYPE for this template
+ * @blockmode:		the type of block operation
+ * @mc:			pointer to the meson_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:		total of all data len done on this template
+ */
+struct meson_alg_template {
+	u32 type;
+	u32 blockmode;
+	union {
+		struct skcipher_alg skcipher;
+	} alg;
+	struct meson_dev *mc;
+#ifdef CONFIG_CRYPTO_DEV_AMLOGIC_GXL_DEBUG
+	unsigned long stat_req;
+	unsigned long stat_fb;
+#endif
+};
+
+int meson_enqueue(struct crypto_async_request *areq, u32 type);
+
+int meson_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
+		     unsigned int keylen);
+int meson_cipher_init(struct crypto_tfm *tfm);
+void meson_cipher_exit(struct crypto_tfm *tfm);
+int meson_skdecrypt(struct skcipher_request *areq);
+int meson_skencrypt(struct skcipher_request *areq);