[PATCH u-boot v2019.04-aspeed-openbmc v2 02/10] crypto: Add driver for Aspeed HACE

[Joel Stanley <joel@jms.id.au>]

The HACE supports MD5, SHA1 and SHA2 family hash functions. This driver
uses it in a polling mode to perform hash calculations over buffers
placed in DRAM.

Co-developed-by: Klaus Heinrich Kiwi <klaus@linux.vnet.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
---
 configs/ast2600_openbmc_spl_emmc_defconfig |   1 +
 drivers/crypto/Kconfig                     |  19 ++
 drivers/crypto/Makefile                    |   1 +
 drivers/crypto/aspeed_hace.c               | 266 +++++++++++++++++++++
 4 files changed, 287 insertions(+)
 create mode 100644 drivers/crypto/aspeed_hace.c

diff --git a/configs/ast2600_openbmc_spl_emmc_defconfig b/configs/ast2600_openbmc_spl_emmc_defconfig
index 5a4d66da1cea..f58a677f1914 100644
--- a/configs/ast2600_openbmc_spl_emmc_defconfig
+++ b/configs/ast2600_openbmc_spl_emmc_defconfig
@@ -97,6 +97,7 @@ CONFIG_SYSCON=y
 CONFIG_SPL_OF_TRANSLATE=y
 CONFIG_CLK=y
 CONFIG_SPL_CLK=y
+CONFIG_ASPEED_HACE=y
 CONFIG_DM_GPIO=y
 CONFIG_ASPEED_GPIO=y
 CONFIG_DM_I2C=y
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 1ea116be7503..e92037d88906 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -2,4 +2,23 @@ menu "Hardware crypto devices"
 
 source drivers/crypto/fsl/Kconfig
 
+config ASPEED_HACE
+	bool "ASPEED Hash and Crypto Engine"
+	depends on ASPEED_AST2600
+	imply SHA_HW_ACCEL
+	imply SHA_PROG_HW_ACCEL
+	imply SHA512
+	imply SHA512_ALGO
+	imply CMD_HASH
+	help
+	 Select this option to enable a driver for using the SHA engine in
+	 the ASPEED BMC SoCs.
+
+	 Enabling this allows the use of SHA operations in hardware without requiring the
+	 SHA software implementations, saving code size.
+
+	 Due to hardware limitations it cannot be used with a FIT placed in SPI
+	 FLASH. Data can only be hashed if it is in SDRAM, making this relevant
+	 for MMC and network boot only.
+
 endmenu
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index efbd1d3fca05..ac93b1295954 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -4,5 +4,6 @@
 # 	http://www.samsung.com
 
 obj-$(CONFIG_EXYNOS_ACE_SHA)	+= ace_sha.o
+obj-$(CONFIG_ASPEED_HACE)	+= aspeed_hace.o
 obj-y += rsa_mod_exp/
 obj-y += fsl/
diff --git a/drivers/crypto/aspeed_hace.c b/drivers/crypto/aspeed_hace.c
new file mode 100644
index 000000000000..a99fb7c249be
--- /dev/null
+++ b/drivers/crypto/aspeed_hace.c
@@ -0,0 +1,266 @@
+/*
+ * (C) Copyright ASPEED Technology Inc.
+ * Copyright 2021 IBM Corp.
+ *
+ * SPDX-License-Identifier:	GPL-2.0-or-later
+ */
+
+#include <common.h>
+#include <clk.h>
+
+#include <log.h>
+#include <asm/io.h>
+#include <malloc.h>
+#include <hash.h>
+
+#include <dm/device.h>
+#include <dm/fdtaddr.h>
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/iopoll.h>
+
+#define ASPEED_HACE_STS			0x1C
+#define  HACE_RSA_ISR			BIT(13)
+#define  HACE_CRYPTO_ISR		BIT(12)
+#define  HACE_HASH_ISR			BIT(9)
+#define  HACE_RSA_BUSY			BIT(2)
+#define  HACE_CRYPTO_BUSY		BIT(1)
+#define  HACE_HASH_BUSY			BIT(0)
+#define ASPEED_HACE_HASH_SRC		0x20
+#define ASPEED_HACE_HASH_DIGEST_BUFF	0x24
+#define ASPEED_HACE_HASH_KEY_BUFF	0x28
+#define ASPEED_HACE_HASH_DATA_LEN	0x2C
+#define  HACE_SG_LAST			BIT(31)
+#define ASPEED_HACE_HASH_CMD		0x30
+#define  HACE_SHA_BE_EN			BIT(3)
+#define  HACE_MD5_LE_EN			BIT(2)
+#define  HACE_ALGO_MD5			0
+#define  HACE_ALGO_SHA1			BIT(5)
+#define  HACE_ALGO_SHA224		BIT(6)
+#define  HACE_ALGO_SHA256		(BIT(4) | BIT(6))
+#define  HACE_ALGO_SHA512		(BIT(5) | BIT(6))
+#define  HACE_ALGO_SHA384		(BIT(5) | BIT(6) | BIT(10))
+#define  HACE_SG_EN			BIT(18)
+
+#define ASPEED_MAX_SG			32
+
+struct aspeed_sg {
+	u32 len;
+	u32 addr;
+};
+
+struct aspeed_hash_ctx {
+	u32 method;
+	u32 digest_size;
+	u32 len;
+	u32 count;
+	struct aspeed_sg list[ASPEED_MAX_SG]; /* Must be 8 byte aligned */
+};
+
+struct aspeed_hace {
+	struct clk clk;
+};
+
+static phys_addr_t base;
+
+static int aspeed_hace_wait_completion(u32 reg, u32 flag, int timeout_us)
+{
+	u32 val;
+
+	return readl_poll_timeout(reg, val, (val & flag) == flag, timeout_us);
+}
+
+static int digest_object(const void *src, unsigned int length, void *digest,
+		  u32 method)
+{
+	if (!((u32)src & BIT(31))) {
+		debug("HACE src out of bounds: can only copy from SDRAM\n");
+		return -EINVAL;
+	}
+
+	if ((u32)digest & 0x7) {
+		debug("HACE dest alignment incorrect: %p\n", digest);
+		return -EINVAL;
+	}
+
+
+	if (readl(base + ASPEED_HACE_STS) & HACE_HASH_BUSY) {
+		debug("HACE error: engine busy\n");
+		return -EBUSY;
+	}
+
+	/* Clear pending completion status */
+	writel(HACE_HASH_ISR, base + ASPEED_HACE_STS);
+
+	writel((u32)src, base + ASPEED_HACE_HASH_SRC);
+	writel((u32)digest, base + ASPEED_HACE_HASH_DIGEST_BUFF);
+	writel(length, base + ASPEED_HACE_HASH_DATA_LEN);
+	writel(HACE_SHA_BE_EN | method, base + ASPEED_HACE_HASH_CMD);
+
+	/* SHA512 hashing appears to have a througput of about 12MB/s */
+	return aspeed_hace_wait_completion(base + ASPEED_HACE_STS,
+			HACE_HASH_ISR,
+			1000 + (length >> 3));
+}
+
+void hw_sha1(const unsigned char *pbuf, unsigned int buf_len,
+	       unsigned char *pout, unsigned int chunk_size)
+{
+	int rc;
+
+	rc = digest_object(pbuf, buf_len, pout, HACE_ALGO_SHA1);
+	if (rc)
+		debug("HACE failure: %d\n", rc);
+}
+
+void hw_sha256(const unsigned char *pbuf, unsigned int buf_len,
+	       unsigned char *pout, unsigned int chunk_size)
+{
+	int rc;
+
+	rc = digest_object(pbuf, buf_len, pout, HACE_ALGO_SHA256);
+	if (rc)
+		debug("HACE failure: %d\n", rc);
+}
+
+void hw_sha512(const unsigned char *pbuf, unsigned int buf_len,
+	       unsigned char *pout, unsigned int chunk_size)
+{
+	int rc;
+
+	rc = digest_object(pbuf, buf_len, pout, HACE_ALGO_SHA512);
+	if (rc)
+		debug("HACE failure: %d\n", rc);
+}
+
+#if IS_ENABLED(CONFIG_SHA_PROG_HW_ACCEL)
+int hw_sha_init(struct hash_algo *algo, void **ctxp)
+{
+	struct aspeed_hash_ctx *ctx;
+	u32 method;
+
+	if (!strcmp(algo->name, "sha1")) {
+		method = HACE_ALGO_SHA1;
+	}
+	else if (!strcmp(algo->name, "sha256")) {
+		method = HACE_ALGO_SHA256;
+	}
+	else if (!strcmp(algo->name, "sha512")) {
+		method = HACE_ALGO_SHA512;
+	}
+	else  {
+		return -ENOTSUPP;
+	}
+
+	ctx = memalign(8, sizeof(*ctx));
+	memset(ctx, '\0', sizeof(*ctx));
+
+	if (ctx == NULL) {
+		debug("HACE error: Cannot allocate memory for context\n");
+		return -ENOMEM;
+	}
+
+	if (((uintptr_t)ctx->list & 0x3) != 0) {
+		printf("HACE error: Invalid alignment for input data\n");
+		return -EINVAL;
+	}
+
+	ctx->method = method | HACE_SG_EN;
+	ctx->digest_size = algo->digest_size;
+	*ctxp = ctx;
+
+	return 0;
+}
+
+int hw_sha_update(struct hash_algo *algo, void *hash_ctx, const void *buf,
+		  unsigned int size, int is_last)
+{
+	struct aspeed_hash_ctx *ctx = hash_ctx;
+	struct aspeed_sg *sg = &ctx->list[ctx->count];
+
+	if (ctx->count >= ARRAY_SIZE(ctx->list)) {
+		debug("HACE error: Reached maximum number of hash segments\n");
+		free(ctx);
+		return -EINVAL;
+	}
+
+	sg->addr = (u32)buf;
+	sg->len = size;
+	if (is_last)
+		sg->len |= HACE_SG_LAST;
+
+	ctx->count++;
+	ctx->len += size;
+
+	return 0;
+}
+
+int hw_sha_finish(struct hash_algo *algo, void *hash_ctx, void *dest_buf, int size)
+{
+	struct aspeed_hash_ctx *ctx = hash_ctx;
+	int rc;
+
+	if (size < ctx->digest_size) {
+		debug("HACE error: insufficient size on destination buffer\n");
+		free(ctx);
+		return -EINVAL;
+	}
+
+	rc = digest_object(ctx->list, ctx->len, dest_buf, ctx->method);
+	if (rc)
+		debug("HACE Scatter-Gather failure\n");
+
+	free(ctx);
+
+	return rc;
+}
+#endif
+
+static int aspeed_hace_probe(struct udevice *dev)
+{
+	struct aspeed_hace *hace = dev_get_priv(dev);
+	int ret;
+
+	ret = clk_get_by_index(dev, 0, &hace->clk);
+	if (ret < 0) {
+		debug("Can't get clock for %s: %d\n", dev->name, ret);
+		return ret;
+	}
+
+	ret = clk_enable(&hace->clk);
+	if (ret) {
+		debug("Failed to enable fsi clock (%d)\n", ret);
+		return ret;
+	}
+
+	/* As the crypto code does not pass us any driver state */
+	base = devfdt_get_addr(dev);
+
+	return ret;
+}
+
+static int aspeed_hace_remove(struct udevice *dev)
+{
+	struct aspeed_hace *hace = dev_get_priv(dev);
+
+	clk_disable(&hace->clk);
+
+	return 0;
+}
+
+static const struct udevice_id aspeed_hace_ids[] = {
+	{ .compatible = "aspeed,ast2600-hace" },
+	{ }
+};
+
+U_BOOT_DRIVER(aspeed_hace) = {
+	.name		= "aspeed_hace",
+	.id		= UCLASS_MISC,
+	.of_match	= aspeed_hace_ids,
+	.probe		= aspeed_hace_probe,
+	.remove 	= aspeed_hace_remove,
+	.priv_auto_alloc_size = sizeof(struct aspeed_hace),
+	.flags  = DM_FLAG_PRE_RELOC,
+};
-- 
2.30.2