MLK-10958 imx: mx6ul support Bus Encryption Engine

This patch is to support Bus Encryption Engine(BEE) for i.MX 6UL.
Supported feature:
1. SNVS key and soft key
2. CTR and ECB mode
3. Specify address region to bee.

Two commands are included:
bee init [key] [mode] [start] [end] - BEE block initial
    "Example: bee init 1 1 0x80000000 0x80010000\n"
bee test [region]
    "Example: bee test 1\n"

Mapping:
[0x10000000 - (0x10000000 + size - 1)] : [start - (start + size - 1)]
[0x30000000 - (0x30000000 + IRAM_SIZE - 1)] : [IRAM_BASE_ADDR -
(IRAM_BASE_ADDR + IRAM_SIZE - 1)]

Whatever start is, start - (start + size -1) will be fixed mapping to
0x10000000 - (0x10000000 + size - 1)

Since default AES region's protected size is SZ_512M, so
on mx6ul evk board, you can not simply run 'bee init', it will
overlap with uboot execution environment, you can use
'bee init 0 0 0x80000000 0x81000000'.

If want to use bee, Need to define CONFIG_CMD_BEE in board configuration
header file, since CONFIG_CMD_BEE default is not enabled.

Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
(cherry picked from commit 29b9bdbbdac9678dba9b7bc2d3662598e9c548a5)
(cherry picked from commit 6d45292ff7e7020a48842f033f8a337daabe4476)

3 files changed, 463 insertions, 1 deletions

diff --git a/arch/arm/cpu/armv7/mx6/Kconfig b/arch/arm/cpu/armv7/mx6/Kconfig
index 744d67a..2757451 100644
--- a/arch/arm/cpu/armv7/mx6/Kconfig
+++ b/arch/arm/cpu/armv7/mx6/Kconfig
@@ -58,6 +58,12 @@ config MX6_DDRCAL
 	  Say "Y" if your board uses dynamic (per-boot) DDR calibration.
 	  If unsure, say N.
 
+config CMD_BEE
+	bool "Enable commands for Bus Encryption Engine(BEE)"
+	depends on MX6UL
+	help
+	  Set "Y" to enable the bee commands 
+
 choice
 	prompt "MX6 board select"
 	optional
diff --git a/arch/arm/cpu/armv7/mx6/Makefile b/arch/arm/cpu/armv7/mx6/Makefile
index 024f703..d240f3a 100644
--- a/arch/arm/cpu/armv7/mx6/Makefile
+++ b/arch/arm/cpu/armv7/mx6/Makefile
@@ -2,7 +2,7 @@
 # (C) Copyright 2000-2006
 # Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 #
-# (C) Copyright 2011 Freescale Semiconductor, Inc.
+# (C) Copyright 2011-2015 Freescale Semiconductor, Inc.
 #
 # SPDX-License-Identifier:	GPL-2.0+
 #
@@ -11,3 +11,6 @@ obj-y	:= soc.o clock.o
 obj-$(CONFIG_SPL_BUILD)	     += ddr.o
 obj-$(CONFIG_MP)             += mp.o
 obj-$(CONFIG_MX6UL_LITESOM)  += litesom.o
+ifdef CONFIG_MX6UL
+obj-$(CONFIG_CMD_BEE)        += bee.o
+endif
diff --git a/arch/arm/cpu/armv7/mx6/bee.c b/arch/arm/cpu/armv7/mx6/bee.c
new file mode 100644
index 0000000..a4bd76d
--- /dev/null
+++ b/arch/arm/cpu/armv7/mx6/bee.c
@@ -0,0 +1,453 @@
+/*
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <asm/io.h>
+#include <asm/arch/mx6_bee.h>
+#include <linux/errno.h>
+#include <asm/system.h>
+#include <common.h>
+#include <command.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#if (defined(CONFIG_SYS_DCACHE_OFF) || defined(CONFIG_SYS_ICACHE_OFF))
+#error "Bee needs Cache Open"
+#endif
+
+struct bee_parameters {
+	int key_method;
+	int mode;
+	u32 start1;
+	u32 size1;
+	u32 start2;
+	u32 size2;
+};
+
+#define SOFT_KEY 0
+#define SNVS_KEY 1
+
+#define ECB_MODE 0
+#define CTR_MODE 1
+
+#define AES_REGION0_ADDR	0x10000000
+#define AES_REGION1_ADDR	0x30000000
+
+static struct bee_parameters para;
+static int bee_inited;
+
+union key_soft {
+	u8 s_key[16];
+	u32 b_key[4];
+};
+
+union key_soft key_bad;
+
+/* software version */
+u8 hw_get_random_byte(void)
+{
+	static u32 lcg_state;
+	static u32 nb_soft = 9876543;
+#define MAX_SOFT_RNG 1024
+	static const u32 a = 1664525;
+	static const u32 c = 1013904223;
+	nb_soft = (nb_soft + 1) % MAX_SOFT_RNG;
+	lcg_state = (a * lcg_state + c);
+	return (u8) (lcg_state >> 24);
+}
+
+/*
+ * Lock bee GPR0 bits
+ * Only reset can release these bits.
+ */
+static int bee_lock(void)
+{
+	int val;
+
+	val = readl(BEE_BASE_ADDR + GPR0);
+	val |= (GPR0_CTRL_CLK_EN_LOCK | GPR0_CTRL_SFTRST_N_LOCK |
+		GPR0_CTRL_AES_MODE_LOCK | GPR0_SEC_LEVEL_LOCK |
+		GPR0_AES_KEY_SEL_LOCK | GPR0_BEE_ENABLE_LOCK);
+	writel(val, BEE_BASE_ADDR + GPR0);
+
+	return 0;
+}
+
+/* Only check bee enable lock is enough */
+static int bee_locked(void)
+{
+	int val;
+
+	val = readl(BEE_BASE_ADDR + GPR0);
+
+	return val & GPR0_BEE_ENABLE_LOCK ? 1 : 0;
+}
+
+int bee_init(struct bee_parameters *p)
+{
+	int i;
+	union key_soft *key = &key_bad;
+	u32 value;
+
+	if (bee_locked()) {
+		printf("BEE already enabled and locked.\n");
+		return CMD_RET_FAILURE;
+	}
+
+	/* CLKGATE, SFTRST */
+	writel(GPR0_CTRL_CLK_EN | GPR0_CTRL_SFTRST_N, BEE_BASE_ADDR + GPR0);
+	/* OFFSET_ADDR0 */
+	writel(p->start1 >> 16, BEE_BASE_ADDR + GPR1);
+	/*
+	 * OFFSET_ADDR1
+	 * Default protect IRAM region, if what you want to protect
+	 * bigger that 512M which is the max size that one AES region
+	 * can protect, we need AES region 1 to cover.
+	 */
+	writel(p->start2 >> 16, BEE_BASE_ADDR + GPR2);
+
+	if (p->key_method == SOFT_KEY) {
+		for (i = 0; i < 16; i++)
+			key->s_key[i] = hw_get_random_byte();
+		/* AES 128 key from software */
+		/* aes0_key0_w0 */
+		writel(key->b_key[0], BEE_BASE_ADDR + GPR3);
+		/* aes0_key0_w1 */
+		writel(key->b_key[1], BEE_BASE_ADDR + GPR4);
+		/* aes0_key0_w2 */
+		writel(key->b_key[2], BEE_BASE_ADDR + GPR5);
+		/* aes0_key0_w3 */
+		writel(key->b_key[3], BEE_BASE_ADDR + GPR6);
+	}
+
+	if (p->mode == ECB_MODE) {
+		value = GPR0_CTRL_CLK_EN | GPR0_CTRL_SFTRST_N |
+			GPR0_SEC_LEVEL_3 | GPR0_AES_KEY_SEL_SNVS |
+			GPR0_BEE_ENABLE | GPR0_CTRL_AES_MODE_ECB;
+		if (p->key_method == SOFT_KEY)
+			value = GPR0_CTRL_CLK_EN | GPR0_CTRL_SFTRST_N |
+				GPR0_SEC_LEVEL_3 | GPR0_AES_KEY_SEL_SOFT |
+				GPR0_BEE_ENABLE | GPR0_CTRL_AES_MODE_ECB;
+		writel(value, BEE_BASE_ADDR + GPR0);
+	} else {
+		for (i = 0; i < 16; i++)
+			key->s_key[i] = hw_get_random_byte();
+		/* aes_key1_w0 */
+		writel(key->b_key[0], BEE_BASE_ADDR + GPR8);
+		/* aes_key1_w1 */
+		writel(key->b_key[1], BEE_BASE_ADDR + GPR9);
+		/* aes_key1_w2 */
+		writel(key->b_key[2], BEE_BASE_ADDR + GPR10);
+		/* aes_key1_w3 */
+		writel(key->b_key[3], BEE_BASE_ADDR + GPR11);
+
+		value = GPR0_CTRL_CLK_EN | GPR0_CTRL_SFTRST_N |
+			GPR0_SEC_LEVEL_3 | GPR0_AES_KEY_SEL_SNVS |
+			GPR0_BEE_ENABLE | GPR0_CTRL_AES_MODE_CTR;
+		if (p->key_method == SOFT_KEY)
+			value = GPR0_CTRL_CLK_EN | GPR0_CTRL_SFTRST_N |
+				GPR0_SEC_LEVEL_3 | GPR0_AES_KEY_SEL_SOFT |
+				GPR0_BEE_ENABLE | GPR0_CTRL_AES_MODE_CTR;
+		writel(value, BEE_BASE_ADDR + GPR0);
+	}
+
+	bee_lock();
+
+	printf("BEE is settings as: %s mode, %s %d key\n",
+	       (p->mode == ECB_MODE) ? "ECB" : "CTR",
+	       (p->key_method == SOFT_KEY) ? "SOFT" : "SNVS HW",
+	       (p->mode == ECB_MODE) ? 128 : 256);
+
+	return CMD_RET_SUCCESS;
+}
+
+int bee_test(struct bee_parameters *p, int region)
+{
+	u32 result = 0, range, address;
+	int i, val;
+	/*
+	 * Test instruction running in AES Region:
+	 * int test(void)
+	 * {
+	 *	return 0x55aa55aa;
+	 * }
+	 * Assemble:
+	 * 0xe59f0000: ldr r0, [pc]
+	 * 0xe12fff1e: bx lr
+	 * 0x55aa55aa: 0x55aa55aa
+	 */
+	u32 inst[3] = {0xe59f0000, 0xe12fff1e, 0x55aa55aa};
+
+	/* Cache enabled? */
+	if ((get_cr() & (CR_I | CR_C)) != (CR_I | CR_C)) {
+		printf("Enable dcache and icache first!\n");
+		return CMD_RET_FAILURE;
+	}
+
+	printf("Test Region %d\nBegin Data test: Writing... ", region);
+
+	range = (region == 0) ? p->size1 : p->size2;
+	address = (region == 0) ? AES_REGION0_ADDR : AES_REGION1_ADDR;
+	for (i = 0; i < range; i = i + 4)
+		writel(i, address + i);
+
+	printf("Finshed Write!\n");
+
+	flush_dcache_range(address, address + range);
+
+	printf("Reading... ");
+	for (i = 0; i < range; i = i + 4) {
+		val = readl(address + i);
+		if (val != i)
+			result++;
+	}
+	printf("Finshed Read!\n");
+
+	if (result > 0)
+		printf("BEE Data Test check Failed!\n");
+	else
+		printf("BEE Data Test Check Passed!\n");
+
+	for (i = 0; i < ARRAY_SIZE(inst); i++)
+		writel(inst[i], address + (i * 4));
+
+	flush_dcache_range(address, address + sizeof(inst));
+
+	val = ((int (*)(void))address)();
+
+	printf("\nBee Instruction test, Program:\n"
+	       "int test(void)\n"
+	       "{\n"
+	       "      return 0x55aa55aa;\n"
+	       "}\n"
+	       "Assemble:\n"
+	       "0xe59f0000: ldr r0, [pc]\n"
+	       "0xe12fff1e: bx lr\n"
+	       "0x55aa55aa: 0x55aa55aa\n"
+	       "Runnint at 0x%x\n", address);
+	if (val == 0x55aa55aa)
+		printf("Bee Instruction Test Passed!\n");
+	else
+		printf("Bee Instruction Test Failed!\n");
+
+	return CMD_RET_SUCCESS;
+}
+
+static int region_valid(u32 start, u32 size)
+{
+	if ((start < PHYS_SDRAM) || (start >= (start + size - 1)) ||
+	    (start >= (PHYS_SDRAM + PHYS_SDRAM_SIZE - 1))) {
+		printf("Invalid start 0x%x, size 0x%x\n", start, size);
+		return -EINVAL;
+	}
+
+	if (size > SZ_512M) {
+		printf("The region size exceeds SZ_512M\n");
+		return -EINVAL;
+	}
+
+	if ((start & 0xFFFF) && (size & 0xFFFF)) {
+		printf("start or size not 64KB aligned!\n");
+		return -EINVAL;
+	}
+
+	if ((start + size - 1) >= (gd->start_addr_sp - CONFIG_STACKSIZE)) {
+		printf("Overlap with uboot execution environment!\n"
+		       "Decrease size or start\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int do_bee_init(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char * const argv[])
+{
+	u32 start, size;
+	int ret;
+	struct bee_parameters *p = &para;
+
+#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
+	enum dcache_option option = DCACHE_WRITETHROUGH;
+#else
+	enum dcache_option option = DCACHE_WRITEBACK;
+#endif
+
+	if (argc > 5)
+		return CMD_RET_USAGE;
+
+	/* Cache enabled? */
+	if ((get_cr() & (CR_I | CR_C)) != (CR_I | CR_C)) {
+		/*
+		 * Here we need icache and dcache both enabled, because
+		 * we may take the protected region for instruction and
+		 * data usage. And icache and dcache both enabled are
+		 * better for performance.
+		 */
+		printf("Please enable dcache and icache first!\n");
+		return CMD_RET_FAILURE;
+	}
+
+	p->key_method = SOFT_KEY;
+	p->mode = ECB_MODE;
+	p->start1 = PHYS_SDRAM;
+	p->size1 = SZ_512M;
+	p->start2 = IRAM_BASE_ADDR;
+	p->size2 = IRAM_SIZE;
+
+	if (argc == 2) {
+		p->key_method = (int)simple_strtoul(argv[1], NULL, 16);
+		p->mode = ECB_MODE;
+		p->start1 = PHYS_SDRAM;
+		p->size1 = SZ_512M;
+	} else if (argc == 3) {
+		p->key_method = (int)simple_strtoul(argv[1], NULL, 16);
+		p->mode = (int)simple_strtoul(argv[2], NULL, 10);
+		p->start1 = PHYS_SDRAM;
+		p->size1 = SZ_512M;
+	} else if ((argc == 4) || (argc == 5)) {
+		p->key_method = (int)simple_strtoul(argv[1], NULL, 16);
+		p->mode = (int)simple_strtoul(argv[2], NULL, 10);
+		start = (u32)simple_strtoul(argv[3], NULL, 16);
+		/* Default size that AES Region0 can protected */
+		size = SZ_512M;
+		if (argc == 5)
+			size = (u32)simple_strtoul(argv[4], NULL, 16);
+		p->start1 = start;
+		p->size1 = size;
+	}
+
+	if ((p->key_method != SOFT_KEY) && (p->key_method != SNVS_KEY))
+		return CMD_RET_USAGE;
+
+	if ((p->mode != ECB_MODE) && (p->mode != CTR_MODE))
+		return CMD_RET_USAGE;
+
+	/*
+	 * No need to check region valid for IRAM, since it is fixed.
+	 * Only check DRAM region here.
+	 */
+	if (region_valid(p->start1, p->size1))
+		return CMD_RET_FAILURE;
+
+	ret = bee_init(p);
+	if (ret)
+		return CMD_RET_FAILURE;
+
+	/*
+	 * Set DCACHE OFF to AES REGION0 and AES REGION1 first
+	 * to avoid possible unexcepted cache settings.
+	 */
+	mmu_set_region_dcache_behaviour(AES_REGION0_ADDR, SZ_1G, DCACHE_OFF);
+
+	mmu_set_region_dcache_behaviour(AES_REGION0_ADDR, p->size1, option);
+
+	mmu_set_region_dcache_behaviour(AES_REGION1_ADDR, p->size2, option);
+
+	printf("Access Region 0x%x - 0x%x to protect 0x%x - 0x%x\n"
+	       "Do not directly access 0x%x - 0x%x\n"
+	       "Access Region 0x%x - 0x%x to protect 0x%x - 0x%x\n"
+	       "Do not directly access 0x%x - 0x%x\n",
+	       AES_REGION0_ADDR, AES_REGION0_ADDR + p->size1 - 1,
+	       p->start1, p->start1 + p->size1 - 1,
+	       p->start1, p->start1 + p->size1 - 1,
+	       AES_REGION1_ADDR, AES_REGION1_ADDR + p->size2 - 1,
+	       p->start2, p->start2 + p->size2 - 1,
+	       p->start2, p->start2 + p->size2 - 1);
+
+	bee_inited = 1;
+
+	return CMD_RET_SUCCESS;
+}
+
+static int do_bee_test(cmd_tbl_t *cmdtp, int flag, int argc,
+		       char * const argv[])
+{
+	int ret;
+	int region;
+
+	if (bee_inited == 0) {
+		printf("Bee not initialized, run bee init first!\n");
+		return CMD_RET_FAILURE;
+	}
+	if (argc > 2)
+		return CMD_RET_USAGE;
+
+	region = 0;
+	if (argc == 2)
+		region = (int)simple_strtoul(argv[1], NULL, 16);
+	/* Only two regions are supported, 0 and 1 */
+	if (region >= 2)
+		return CMD_RET_USAGE;
+
+	ret = bee_test(&para, region);
+	if (ret)
+		return CMD_RET_FAILURE;
+
+	return CMD_RET_SUCCESS;
+}
+
+static cmd_tbl_t cmd_bmp_sub[] = {
+	U_BOOT_CMD_MKENT(init, 5, 0, do_bee_init, "", ""),
+	U_BOOT_CMD_MKENT(test, 2, 0, do_bee_test, "", ""),
+};
+
+static int do_bee_ops(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	cmd_tbl_t *c;
+
+	c = find_cmd_tbl(argv[1], &cmd_bmp_sub[0], ARRAY_SIZE(cmd_bmp_sub));
+
+	/* Drop off the 'bee' command argument */
+	argc--;
+	argv++;
+
+	if (c)
+		return  c->cmd(cmdtp, flag, argc, argv);
+	else
+		return CMD_RET_USAGE;
+}
+
+U_BOOT_CMD(
+	bee, CONFIG_SYS_MAXARGS, 1, do_bee_ops,
+	"BEE function test",
+	"init [key] [mode] [start] [size]	- BEE block initial\n"
+	"  key: 0 | 1, 0 means software key, 1 means SNVS random key\n"
+	"  mode: 0 | 1, 0 means ECB mode, 1 means CTR mode\n"
+	"  start: start address that you want to protect\n"
+	"  size: The size of the area that you want to protect\n"
+	"  start and end(start + size) addr both should be 64KB aligned.\n"
+	"\n"
+	" After initialization, the mapping:\n"
+	" 1. [0x10000000 - (0x10000000 + size - 1)] <--->\n"
+	"    [start - (start + size - 1)]\n"
+	"    Here [start - (start + size -1)] is fixed mapping to\n"
+	"    [0x10000000 - (0x10000000 + size - 1)], whatever start is.\n"
+	" 2. [0x30000000 - (0x30000000 + IRAM_SIZE - 1)] <--->\n"
+	"    [IRAM_BASE_ADDR - (IRAM_BASE_ADDR + IRAM_SIZE - 1)]\n"
+	"\n"
+	" Note: Here we only use AES region 0 to protect the DRAM\n"
+	"       area that you specified, max size SZ_512M.\n"
+	"       AES region 1 is used to protect IRAM area.\n"
+	" Example:\n"
+	" 1. bee init 1 1 0xa0000000 0x10000\n"
+	"    Access 0x10000000 - 0x10010000 to protect 0xa0000000 - 0xa0010000\n"
+	" 2. bee init 1 1 0x80000000 0x20000\n"
+	"    Access 0x10000000 - 0x10020000 to protect 0x80000000 - 0x80020000\n"
+	"\n"
+	" Default configuration if only `bee init` without any args:\n"
+	" 1. software key\n"
+	" 2. ECB mode\n"
+	" 3. Address protected:\n"
+	"   Remapped Region0: PHYS_SDRAM - PHYS_SDRAM + SZ_512M\n"
+	"   Remapped Region1: IRAM_BASE_ADDR - IRAM_BASE_ADDR + IRAM_SIZE\n"
+	" 4. Default Mapping for 6UL:\n"
+	"   [0x10000000 - 0x2FFFFFFF] <-> [0x80000000 - 0x9FFFFFFF]\n"
+	"   [0x30000000 - 0x3001FFFF] <-> [0x00900000 - 0x0091FFFF]\n"
+	"\n"
+	"bee test [region]			- BEE function test\n"
+	"  region: 0 | 1, 0 means region0, 1 means regions1\n"
+);
+