xref: /openbmc/u-boot/arch/arm/mach-stm32mp/cpu.c (revision 53deb24d)
1 // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
2 /*
3  * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
4  */
5 #include <common.h>
6 #include <clk.h>
7 #include <asm/io.h>
8 #include <asm/arch/stm32.h>
9 #include <asm/arch/sys_proto.h>
10 #include <dm/uclass.h>
11 
12 /* RCC register */
13 #define RCC_TZCR		(STM32_RCC_BASE + 0x00)
14 #define RCC_DBGCFGR		(STM32_RCC_BASE + 0x080C)
15 #define RCC_BDCR		(STM32_RCC_BASE + 0x0140)
16 #define RCC_MP_APB5ENSETR	(STM32_RCC_BASE + 0x0208)
17 #define RCC_BDCR_VSWRST		BIT(31)
18 #define RCC_BDCR_RTCSRC		GENMASK(17, 16)
19 #define RCC_DBGCFGR_DBGCKEN	BIT(8)
20 
21 /* Security register */
22 #define ETZPC_TZMA1_SIZE	(STM32_ETZPC_BASE + 0x04)
23 #define ETZPC_DECPROT0		(STM32_ETZPC_BASE + 0x10)
24 
25 #define TZC_GATE_KEEPER		(STM32_TZC_BASE + 0x008)
26 #define TZC_REGION_ATTRIBUTE0	(STM32_TZC_BASE + 0x110)
27 #define TZC_REGION_ID_ACCESS0	(STM32_TZC_BASE + 0x114)
28 
29 #define TAMP_CR1		(STM32_TAMP_BASE + 0x00)
30 
31 #define PWR_CR1			(STM32_PWR_BASE + 0x00)
32 #define PWR_CR1_DBP		BIT(8)
33 
34 /* DBGMCU register */
35 #define DBGMCU_IDC		(STM32_DBGMCU_BASE + 0x00)
36 #define DBGMCU_APB4FZ1		(STM32_DBGMCU_BASE + 0x2C)
37 #define DBGMCU_APB4FZ1_IWDG2	BIT(2)
38 #define DBGMCU_IDC_DEV_ID_MASK	GENMASK(11, 0)
39 #define DBGMCU_IDC_DEV_ID_SHIFT	0
40 #define DBGMCU_IDC_REV_ID_MASK	GENMASK(31, 16)
41 #define DBGMCU_IDC_REV_ID_SHIFT	16
42 
43 /* boot interface from Bootrom
44  * - boot instance = bit 31:16
45  * - boot device = bit 15:0
46  */
47 #define BOOTROM_PARAM_ADDR	0x2FFC0078
48 #define BOOTROM_MODE_MASK	GENMASK(15, 0)
49 #define BOOTROM_MODE_SHIFT	0
50 #define BOOTROM_INSTANCE_MASK	 GENMASK(31, 16)
51 #define BOOTROM_INSTANCE_SHIFT	16
52 
53 #if !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD)
54 static void security_init(void)
55 {
56 	/* Disable the backup domain write protection */
57 	/* the protection is enable at each reset by hardware */
58 	/* And must be disable by software */
59 	setbits_le32(PWR_CR1, PWR_CR1_DBP);
60 
61 	while (!(readl(PWR_CR1) & PWR_CR1_DBP))
62 		;
63 
64 	/* If RTC clock isn't enable so this is a cold boot then we need
65 	 * to reset the backup domain
66 	 */
67 	if (!(readl(RCC_BDCR) & RCC_BDCR_RTCSRC)) {
68 		setbits_le32(RCC_BDCR, RCC_BDCR_VSWRST);
69 		while (!(readl(RCC_BDCR) & RCC_BDCR_VSWRST))
70 			;
71 		clrbits_le32(RCC_BDCR, RCC_BDCR_VSWRST);
72 	}
73 
74 	/* allow non secure access in Write/Read for all peripheral */
75 	writel(GENMASK(25, 0), ETZPC_DECPROT0);
76 
77 	/* Open SYSRAM for no secure access */
78 	writel(0x0, ETZPC_TZMA1_SIZE);
79 
80 	/* enable TZC1 TZC2 clock */
81 	writel(BIT(11) | BIT(12), RCC_MP_APB5ENSETR);
82 
83 	/* Region 0 set to no access by default */
84 	/* bit 0 / 16 => nsaid0 read/write Enable
85 	 * bit 1 / 17 => nsaid1 read/write Enable
86 	 * ...
87 	 * bit 15 / 31 => nsaid15 read/write Enable
88 	 */
89 	writel(0xFFFFFFFF, TZC_REGION_ID_ACCESS0);
90 	/* bit 30 / 31 => Secure Global Enable : write/read */
91 	/* bit 0 / 1 => Region Enable for filter 0/1 */
92 	writel(BIT(0) | BIT(1) | BIT(30) | BIT(31), TZC_REGION_ATTRIBUTE0);
93 
94 	/* Enable Filter 0 and 1 */
95 	setbits_le32(TZC_GATE_KEEPER, BIT(0) | BIT(1));
96 
97 	/* RCC trust zone deactivated */
98 	writel(0x0, RCC_TZCR);
99 
100 	/* TAMP: deactivate the internal tamper
101 	 * Bit 23 ITAMP8E: monotonic counter overflow
102 	 * Bit 20 ITAMP5E: RTC calendar overflow
103 	 * Bit 19 ITAMP4E: HSE monitoring
104 	 * Bit 18 ITAMP3E: LSE monitoring
105 	 * Bit 16 ITAMP1E: RTC power domain supply monitoring
106 	 */
107 	writel(0x0, TAMP_CR1);
108 }
109 
110 /*
111  * Debug init
112  */
113 static void dbgmcu_init(void)
114 {
115 	setbits_le32(RCC_DBGCFGR, RCC_DBGCFGR_DBGCKEN);
116 
117 	/* Freeze IWDG2 if Cortex-A7 is in debug mode */
118 	setbits_le32(DBGMCU_APB4FZ1, DBGMCU_APB4FZ1_IWDG2);
119 }
120 #endif /* !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD) */
121 
122 static u32 get_bootmode(void)
123 {
124 	u32 boot_mode;
125 #if !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD)
126 	u32 bootrom_itf = readl(BOOTROM_PARAM_ADDR);
127 	u32 bootrom_device, bootrom_instance;
128 
129 	bootrom_device =
130 		(bootrom_itf & BOOTROM_MODE_MASK) >> BOOTROM_MODE_SHIFT;
131 	bootrom_instance =
132 		(bootrom_itf & BOOTROM_INSTANCE_MASK) >> BOOTROM_INSTANCE_SHIFT;
133 	boot_mode =
134 		((bootrom_device << BOOT_TYPE_SHIFT) & BOOT_TYPE_MASK) |
135 		((bootrom_instance << BOOT_INSTANCE_SHIFT) &
136 		 BOOT_INSTANCE_MASK);
137 
138 	/* save the boot mode in TAMP backup register */
139 	clrsetbits_le32(TAMP_BOOT_CONTEXT,
140 			TAMP_BOOT_MODE_MASK,
141 			boot_mode << TAMP_BOOT_MODE_SHIFT);
142 #else
143 	/* read TAMP backup register */
144 	boot_mode = (readl(TAMP_BOOT_CONTEXT) & TAMP_BOOT_MODE_MASK) >>
145 		    TAMP_BOOT_MODE_SHIFT;
146 #endif
147 	return boot_mode;
148 }
149 
150 /*
151  * Early system init
152  */
153 int arch_cpu_init(void)
154 {
155 	/* early armv7 timer init: needed for polling */
156 	timer_init();
157 
158 #if !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD)
159 	dbgmcu_init();
160 
161 	security_init();
162 #endif
163 	/* get bootmode from BootRom context: saved in TAMP register */
164 	get_bootmode();
165 
166 	return 0;
167 }
168 
169 void enable_caches(void)
170 {
171 	/* Enable D-cache. I-cache is already enabled in start.S */
172 	dcache_enable();
173 }
174 
175 static u32 read_idc(void)
176 {
177 	setbits_le32(RCC_DBGCFGR, RCC_DBGCFGR_DBGCKEN);
178 
179 	return readl(DBGMCU_IDC);
180 }
181 
182 u32 get_cpu_rev(void)
183 {
184 	return (read_idc() & DBGMCU_IDC_REV_ID_MASK) >> DBGMCU_IDC_REV_ID_SHIFT;
185 }
186 
187 u32 get_cpu_type(void)
188 {
189 	return (read_idc() & DBGMCU_IDC_DEV_ID_MASK) >> DBGMCU_IDC_DEV_ID_SHIFT;
190 }
191 
192 #if defined(CONFIG_DISPLAY_CPUINFO)
193 int print_cpuinfo(void)
194 {
195 	char *cpu_s, *cpu_r;
196 
197 	switch (get_cpu_type()) {
198 	case CPU_STMP32MP15x:
199 		cpu_s = "15x";
200 		break;
201 	default:
202 		cpu_s = "?";
203 		break;
204 	}
205 
206 	switch (get_cpu_rev()) {
207 	case CPU_REVA:
208 		cpu_r = "A";
209 		break;
210 	case CPU_REVB:
211 		cpu_r = "B";
212 		break;
213 	default:
214 		cpu_r = "?";
215 		break;
216 	}
217 
218 	printf("CPU: STM32MP%s.%s\n", cpu_s, cpu_r);
219 
220 	return 0;
221 }
222 #endif /* CONFIG_DISPLAY_CPUINFO */
223 
224 static void setup_boot_mode(void)
225 {
226 	char cmd[60];
227 	u32 boot_ctx = readl(TAMP_BOOT_CONTEXT);
228 	u32 boot_mode =
229 		(boot_ctx & TAMP_BOOT_MODE_MASK) >> TAMP_BOOT_MODE_SHIFT;
230 	int instance = (boot_mode & TAMP_BOOT_INSTANCE_MASK) - 1;
231 
232 	pr_debug("%s: boot_ctx=0x%x => boot_mode=%x, instance=%d\n",
233 		 __func__, boot_ctx, boot_mode, instance);
234 
235 	switch (boot_mode & TAMP_BOOT_DEVICE_MASK) {
236 	case BOOT_SERIAL_UART:
237 		sprintf(cmd, "%d", instance);
238 		env_set("boot_device", "uart");
239 		env_set("boot_instance", cmd);
240 		break;
241 	case BOOT_SERIAL_USB:
242 		env_set("boot_device", "usb");
243 		env_set("boot_instance", "0");
244 		break;
245 	case BOOT_FLASH_SD:
246 	case BOOT_FLASH_EMMC:
247 		sprintf(cmd, "%d", instance);
248 		env_set("boot_device", "mmc");
249 		env_set("boot_instance", cmd);
250 		break;
251 	case BOOT_FLASH_NAND:
252 		env_set("boot_device", "nand");
253 		env_set("boot_instance", "0");
254 		break;
255 	case BOOT_FLASH_NOR:
256 		env_set("boot_device", "nor");
257 		env_set("boot_instance", "0");
258 		break;
259 	default:
260 		pr_debug("unexpected boot mode = %x\n", boot_mode);
261 		break;
262 	}
263 }
264 
265 int arch_misc_init(void)
266 {
267 	setup_boot_mode();
268 
269 	return 0;
270 }
271