crypto: allwinner - Add sun8i-ss cryptographic offloader

The Security System is an hardware cryptographic offloader present
on Allwinner SoCs A80 and A83T.
It is different from the previous sun4i-ss.

This driver supports AES cipher in CBC and ECB mode.
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/allwinner/Kconfig

@@ -58,3 +58,30 @@ config CRYPTO_DEV_SUN8I_CE_DEBUG
 	  Say y to enable sun8i-ce debug stats.
 	  This will create /sys/kernel/debug/sun8i-ce/stats for displaying
 	  the number of requests per flow and per algorithm.
+
+config CRYPTO_DEV_SUN8I_SS
+	tristate "Support for Allwinner Security System cryptographic offloader"
+	select CRYPTO_BLKCIPHER
+	select CRYPTO_ENGINE
+	select CRYPTO_ECB
+	select CRYPTO_CBC
+	select CRYPTO_AES
+	select CRYPTO_DES
+	depends on CRYPTO_DEV_ALLWINNER
+	depends on PM
+	help
+	  Select y here to have support for the Security System available on
+	  Allwinner SoC A80, A83T.
+	  The Security System handle AES/3DES ciphers in ECB/CBC mode.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called sun8i-ss.
+
+config CRYPTO_DEV_SUN8I_SS_DEBUG
+	bool "Enable sun8i-ss stats"
+	depends on CRYPTO_DEV_SUN8I_SS
+	depends on DEBUG_FS
+	help
+	  Say y to enable sun8i-ss debug stats.
+	  This will create /sys/kernel/debug/sun8i-ss/stats for displaying
+	  the number of requests per flow and per algorithm.

drivers/crypto/allwinner/Makefile

 obj-$(CONFIG_CRYPTO_DEV_SUN4I_SS) += sun4i-ss/
 obj-$(CONFIG_CRYPTO_DEV_SUN8I_CE) += sun8i-ce/
+obj-$(CONFIG_CRYPTO_DEV_SUN8I_SS) += sun8i-ss/

drivers/crypto/allwinner/sun8i-ss/Makefile

+obj-$(CONFIG_CRYPTO_DEV_SUN8I_SS) += sun8i-ss.o
+sun8i-ss-y += sun8i-ss-core.o sun8i-ss-cipher.o

drivers/crypto/allwinner/sun8i-ss/sun8i-ss.h

+/* 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/skcipher.h>
+#include <linux/atomic.h>
+#include <linux/debugfs.h>
+#include <linux/crypto.h>
+
+#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_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_FLOW0	BIT(30)
+#define SS_FLOW1	BIT(31)
+
+#define MAX_SG 8
+
+#define MAXFLOW 2
+
+#define SS_MAX_CLOCKS 2
+
+#define SS_DIE_ID_SHIFT	20
+#define SS_DIE_ID_MASK	0x07
+
+/*
+ * 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
+ * @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];
+	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
+ */
+struct sun8i_ss_flow {
+	struct crypto_engine *engine;
+	struct completion complete;
+	int status;
+#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 IV
+ * @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 biv
+ * @keylen:	keylen for this request
+ * @biv:	buffer which contain the IV
+ */
+struct sun8i_cipher_req_ctx {
+	struct sginfo t_src[MAX_SG];
+	struct sginfo t_dst[MAX_SG];
+	u32 p_key;
+	u32 p_iv;
+	u32 method;
+	u32 op_mode;
+	u32 op_dir;
+	int flow;
+	unsigned int ivlen;
+	unsigned int keylen;
+	void *biv;
+};
+
+/*
+ * struct sun8i_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
+ * @ss:			pointer to the private data of driver handling this TFM
+ * @fallback_tfm:	pointer to the fallback TFM
+ */
+struct sun8i_cipher_tfm_ctx {
+	struct crypto_engine_ctx enginectx;
+	u32 *key;
+	u32 keylen;
+	struct sun8i_ss_dev *ss;
+	struct crypto_sync_skcipher *fallback_tfm;
+};
+
+/*
+ * 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:		total of all data len done on this template
+ */
+struct sun8i_ss_alg_template {
+	u32 type;
+	u32 ss_algo_id;
+	u32 ss_blockmode;
+	struct sun8i_ss_dev *ss;
+	union {
+		struct skcipher_alg skcipher;
+	} alg;
+#ifdef CONFIG_CRYPTO_DEV_SUN8I_SS_DEBUG
+	unsigned long stat_req;
+	unsigned long stat_fb;
+#endif
+};
+
+int sun8i_ss_enqueue(struct crypto_async_request *areq, u32 type);
+
+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_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);