xref: /openbmc/linux/arch/arm/mach-exynos/firmware.c (revision 78700c0a)
1 /*
2  * Copyright (C) 2012 Samsung Electronics.
3  * Kyungmin Park <kyungmin.park@samsung.com>
4  * Tomasz Figa <t.figa@samsung.com>
5  *
6  * This program is free software,you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/io.h>
13 #include <linux/init.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 
17 #include <asm/cacheflush.h>
18 #include <asm/cputype.h>
19 #include <asm/firmware.h>
20 #include <asm/hardware/cache-l2x0.h>
21 #include <asm/suspend.h>
22 
23 #include "common.h"
24 #include "smc.h"
25 
26 #define EXYNOS_BOOT_ADDR	0x8
27 #define EXYNOS_BOOT_FLAG	0xc
28 
29 static void exynos_save_cp15(void)
30 {
31 	/* Save Power control and Diagnostic registers */
32 	asm ("mrc p15, 0, %0, c15, c0, 0\n"
33 	     "mrc p15, 0, %1, c15, c0, 1\n"
34 	     : "=r" (cp15_save_power), "=r" (cp15_save_diag)
35 	     : : "cc");
36 }
37 
38 static int exynos_do_idle(unsigned long mode)
39 {
40 	switch (mode) {
41 	case FW_DO_IDLE_AFTR:
42 		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
43 			exynos_save_cp15();
44 		__raw_writel(virt_to_phys(exynos_cpu_resume_ns),
45 			     sysram_ns_base_addr + 0x24);
46 		__raw_writel(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
47 		if (soc_is_exynos3250()) {
48 			flush_cache_all();
49 			exynos_smc(SMC_CMD_SAVE, OP_TYPE_CORE,
50 				   SMC_POWERSTATE_IDLE, 0);
51 			exynos_smc(SMC_CMD_SHUTDOWN, OP_TYPE_CLUSTER,
52 				   SMC_POWERSTATE_IDLE, 0);
53 		} else
54 			exynos_smc(SMC_CMD_CPU0AFTR, 0, 0, 0);
55 		break;
56 	case FW_DO_IDLE_SLEEP:
57 		exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
58 	}
59 	return 0;
60 }
61 
62 static int exynos_cpu_boot(int cpu)
63 {
64 	/*
65 	 * Exynos3250 doesn't need to send smc command for secondary CPU boot
66 	 * because Exynos3250 removes WFE in secure mode.
67 	 */
68 	if (soc_is_exynos3250())
69 		return 0;
70 
71 	/*
72 	 * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
73 	 * But, Exynos4212 has only one secondary CPU so second parameter
74 	 * isn't used for informing secure firmware about CPU id.
75 	 */
76 	if (soc_is_exynos4212())
77 		cpu = 0;
78 
79 	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
80 	return 0;
81 }
82 
83 static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
84 {
85 	void __iomem *boot_reg;
86 
87 	if (!sysram_ns_base_addr)
88 		return -ENODEV;
89 
90 	boot_reg = sysram_ns_base_addr + 0x1c;
91 
92 	/*
93 	 * Almost all Exynos-series of SoCs that run in secure mode don't need
94 	 * additional offset for every CPU, with Exynos4412 being the only
95 	 * exception.
96 	 */
97 	if (soc_is_exynos4412())
98 		boot_reg += 4 * cpu;
99 
100 	__raw_writel(boot_addr, boot_reg);
101 	return 0;
102 }
103 
104 static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
105 {
106 	void __iomem *boot_reg;
107 
108 	if (!sysram_ns_base_addr)
109 		return -ENODEV;
110 
111 	boot_reg = sysram_ns_base_addr + 0x1c;
112 
113 	if (soc_is_exynos4412())
114 		boot_reg += 4 * cpu;
115 
116 	*boot_addr = __raw_readl(boot_reg);
117 	return 0;
118 }
119 
120 static int exynos_cpu_suspend(unsigned long arg)
121 {
122 	flush_cache_all();
123 	outer_flush_all();
124 
125 	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
126 
127 	pr_info("Failed to suspend the system\n");
128 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
129 	return 1;
130 }
131 
132 static int exynos_suspend(void)
133 {
134 	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
135 		exynos_save_cp15();
136 
137 	writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
138 	writel(virt_to_phys(exynos_cpu_resume_ns),
139 		sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
140 
141 	return cpu_suspend(0, exynos_cpu_suspend);
142 }
143 
144 static int exynos_resume(void)
145 {
146 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
147 
148 	return 0;
149 }
150 
151 static const struct firmware_ops exynos_firmware_ops = {
152 	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
153 	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
154 	.get_cpu_boot_addr	= exynos_get_cpu_boot_addr,
155 	.cpu_boot		= exynos_cpu_boot,
156 	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
157 	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
158 };
159 
160 static void exynos_l2_write_sec(unsigned long val, unsigned reg)
161 {
162 	static int l2cache_enabled;
163 
164 	switch (reg) {
165 	case L2X0_CTRL:
166 		if (val & L2X0_CTRL_EN) {
167 			/*
168 			 * Before the cache can be enabled, due to firmware
169 			 * design, SMC_CMD_L2X0INVALL must be called.
170 			 */
171 			if (!l2cache_enabled) {
172 				exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
173 				l2cache_enabled = 1;
174 			}
175 		} else {
176 			l2cache_enabled = 0;
177 		}
178 		exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
179 		break;
180 
181 	case L2X0_DEBUG_CTRL:
182 		exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
183 		break;
184 
185 	default:
186 		WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
187 	}
188 }
189 
190 static void exynos_l2_configure(const struct l2x0_regs *regs)
191 {
192 	exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
193 		   regs->prefetch_ctrl);
194 	exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
195 }
196 
197 void __init exynos_firmware_init(void)
198 {
199 	struct device_node *nd;
200 	const __be32 *addr;
201 
202 	nd = of_find_compatible_node(NULL, NULL,
203 					"samsung,secure-firmware");
204 	if (!nd)
205 		return;
206 
207 	addr = of_get_address(nd, 0, NULL, NULL);
208 	if (!addr) {
209 		pr_err("%s: No address specified.\n", __func__);
210 		return;
211 	}
212 
213 	pr_info("Running under secure firmware.\n");
214 
215 	register_firmware_ops(&exynos_firmware_ops);
216 
217 	/*
218 	 * Exynos 4 SoCs (based on Cortex A9 and equipped with L2C-310),
219 	 * running under secure firmware, require certain registers of L2
220 	 * cache controller to be written in secure mode. Here .write_sec
221 	 * callback is provided to perform necessary SMC calls.
222 	 */
223 	if (IS_ENABLED(CONFIG_CACHE_L2X0) &&
224 	    read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
225 		outer_cache.write_sec = exynos_l2_write_sec;
226 		outer_cache.configure = exynos_l2_configure;
227 	}
228 }
229 
230 #define REG_CPU_STATE_ADDR	(sysram_ns_base_addr + 0x28)
231 #define BOOT_MODE_MASK		0x1f
232 
233 void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
234 {
235 	unsigned int tmp;
236 
237 	tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
238 
239 	if (mode & BOOT_MODE_MASK)
240 		tmp &= ~BOOT_MODE_MASK;
241 
242 	tmp |= mode;
243 	__raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
244 }
245 
246 void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
247 {
248 	unsigned int tmp;
249 
250 	tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
251 	tmp &= ~mode;
252 	__raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
253 }
254