xref: /openbmc/linux/arch/arm/mach-exynos/firmware.c (revision a2cce7a9)
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 <mach/map.h>
24 
25 #include "common.h"
26 #include "smc.h"
27 
28 #define EXYNOS_BOOT_ADDR	0x8
29 #define EXYNOS_BOOT_FLAG	0xc
30 
31 static void exynos_save_cp15(void)
32 {
33 	/* Save Power control and Diagnostic registers */
34 	asm ("mrc p15, 0, %0, c15, c0, 0\n"
35 	     "mrc p15, 0, %1, c15, c0, 1\n"
36 	     : "=r" (cp15_save_power), "=r" (cp15_save_diag)
37 	     : : "cc");
38 }
39 
40 static int exynos_do_idle(unsigned long mode)
41 {
42 	switch (mode) {
43 	case FW_DO_IDLE_AFTR:
44 		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
45 			exynos_save_cp15();
46 		__raw_writel(virt_to_phys(exynos_cpu_resume_ns),
47 			     sysram_ns_base_addr + 0x24);
48 		__raw_writel(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
49 		if (soc_is_exynos3250()) {
50 			flush_cache_all();
51 			exynos_smc(SMC_CMD_SAVE, OP_TYPE_CORE,
52 				   SMC_POWERSTATE_IDLE, 0);
53 			exynos_smc(SMC_CMD_SHUTDOWN, OP_TYPE_CLUSTER,
54 				   SMC_POWERSTATE_IDLE, 0);
55 		} else
56 			exynos_smc(SMC_CMD_CPU0AFTR, 0, 0, 0);
57 		break;
58 	case FW_DO_IDLE_SLEEP:
59 		exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
60 	}
61 	return 0;
62 }
63 
64 static int exynos_cpu_boot(int cpu)
65 {
66 	/*
67 	 * Exynos3250 doesn't need to send smc command for secondary CPU boot
68 	 * because Exynos3250 removes WFE in secure mode.
69 	 */
70 	if (soc_is_exynos3250())
71 		return 0;
72 
73 	/*
74 	 * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
75 	 * But, Exynos4212 has only one secondary CPU so second parameter
76 	 * isn't used for informing secure firmware about CPU id.
77 	 */
78 	if (soc_is_exynos4212())
79 		cpu = 0;
80 
81 	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
82 	return 0;
83 }
84 
85 static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
86 {
87 	void __iomem *boot_reg;
88 
89 	if (!sysram_ns_base_addr)
90 		return -ENODEV;
91 
92 	boot_reg = sysram_ns_base_addr + 0x1c;
93 
94 	/*
95 	 * Almost all Exynos-series of SoCs that run in secure mode don't need
96 	 * additional offset for every CPU, with Exynos4412 being the only
97 	 * exception.
98 	 */
99 	if (soc_is_exynos4412())
100 		boot_reg += 4 * cpu;
101 
102 	__raw_writel(boot_addr, boot_reg);
103 	return 0;
104 }
105 
106 static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
107 {
108 	void __iomem *boot_reg;
109 
110 	if (!sysram_ns_base_addr)
111 		return -ENODEV;
112 
113 	boot_reg = sysram_ns_base_addr + 0x1c;
114 
115 	if (soc_is_exynos4412())
116 		boot_reg += 4 * cpu;
117 
118 	*boot_addr = __raw_readl(boot_reg);
119 	return 0;
120 }
121 
122 static int exynos_cpu_suspend(unsigned long arg)
123 {
124 	flush_cache_all();
125 	outer_flush_all();
126 
127 	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
128 
129 	pr_info("Failed to suspend the system\n");
130 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
131 	return 1;
132 }
133 
134 static int exynos_suspend(void)
135 {
136 	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
137 		exynos_save_cp15();
138 
139 	writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
140 	writel(virt_to_phys(exynos_cpu_resume_ns),
141 		sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
142 
143 	return cpu_suspend(0, exynos_cpu_suspend);
144 }
145 
146 static int exynos_resume(void)
147 {
148 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
149 
150 	return 0;
151 }
152 
153 static const struct firmware_ops exynos_firmware_ops = {
154 	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
155 	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
156 	.get_cpu_boot_addr	= exynos_get_cpu_boot_addr,
157 	.cpu_boot		= exynos_cpu_boot,
158 	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
159 	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
160 };
161 
162 static void exynos_l2_write_sec(unsigned long val, unsigned reg)
163 {
164 	static int l2cache_enabled;
165 
166 	switch (reg) {
167 	case L2X0_CTRL:
168 		if (val & L2X0_CTRL_EN) {
169 			/*
170 			 * Before the cache can be enabled, due to firmware
171 			 * design, SMC_CMD_L2X0INVALL must be called.
172 			 */
173 			if (!l2cache_enabled) {
174 				exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
175 				l2cache_enabled = 1;
176 			}
177 		} else {
178 			l2cache_enabled = 0;
179 		}
180 		exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
181 		break;
182 
183 	case L2X0_DEBUG_CTRL:
184 		exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
185 		break;
186 
187 	default:
188 		WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
189 	}
190 }
191 
192 static void exynos_l2_configure(const struct l2x0_regs *regs)
193 {
194 	exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
195 		   regs->prefetch_ctrl);
196 	exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
197 }
198 
199 void __init exynos_firmware_init(void)
200 {
201 	struct device_node *nd;
202 	const __be32 *addr;
203 
204 	nd = of_find_compatible_node(NULL, NULL,
205 					"samsung,secure-firmware");
206 	if (!nd)
207 		return;
208 
209 	addr = of_get_address(nd, 0, NULL, NULL);
210 	if (!addr) {
211 		pr_err("%s: No address specified.\n", __func__);
212 		return;
213 	}
214 
215 	pr_info("Running under secure firmware.\n");
216 
217 	register_firmware_ops(&exynos_firmware_ops);
218 
219 	/*
220 	 * Exynos 4 SoCs (based on Cortex A9 and equipped with L2C-310),
221 	 * running under secure firmware, require certain registers of L2
222 	 * cache controller to be written in secure mode. Here .write_sec
223 	 * callback is provided to perform necessary SMC calls.
224 	 */
225 	if (IS_ENABLED(CONFIG_CACHE_L2X0) &&
226 	    read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
227 		outer_cache.write_sec = exynos_l2_write_sec;
228 		outer_cache.configure = exynos_l2_configure;
229 	}
230 }
231 
232 #define REG_CPU_STATE_ADDR	(sysram_ns_base_addr + 0x28)
233 #define BOOT_MODE_MASK		0x1f
234 
235 void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
236 {
237 	unsigned int tmp;
238 
239 	tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
240 
241 	if (mode & BOOT_MODE_MASK)
242 		tmp &= ~BOOT_MODE_MASK;
243 
244 	tmp |= mode;
245 	__raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
246 }
247 
248 void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
249 {
250 	unsigned int tmp;
251 
252 	tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
253 	tmp &= ~mode;
254 	__raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
255 }
256