xref: /openbmc/linux/arch/arm/mach-exynos/firmware.c (revision 4f3db074)
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_SLEEP_MAGIC	0x00000bad
29 #define EXYNOS_AFTR_MAGIC	0xfcba0d10
30 #define EXYNOS_BOOT_ADDR	0x8
31 #define EXYNOS_BOOT_FLAG	0xc
32 
33 static void exynos_save_cp15(void)
34 {
35 	/* Save Power control and Diagnostic registers */
36 	asm ("mrc p15, 0, %0, c15, c0, 0\n"
37 	     "mrc p15, 0, %1, c15, c0, 1\n"
38 	     : "=r" (cp15_save_power), "=r" (cp15_save_diag)
39 	     : : "cc");
40 }
41 
42 static int exynos_do_idle(unsigned long mode)
43 {
44 	switch (mode) {
45 	case FW_DO_IDLE_AFTR:
46 		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
47 			exynos_save_cp15();
48 		__raw_writel(virt_to_phys(exynos_cpu_resume_ns),
49 			     sysram_ns_base_addr + 0x24);
50 		__raw_writel(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
51 		if (soc_is_exynos3250()) {
52 			exynos_smc(SMC_CMD_SAVE, OP_TYPE_CORE,
53 				   SMC_POWERSTATE_IDLE, 0);
54 			exynos_smc(SMC_CMD_SHUTDOWN, OP_TYPE_CLUSTER,
55 				   SMC_POWERSTATE_IDLE, 0);
56 		} else
57 			exynos_smc(SMC_CMD_CPU0AFTR, 0, 0, 0);
58 		break;
59 	case FW_DO_IDLE_SLEEP:
60 		exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
61 	}
62 	return 0;
63 }
64 
65 static int exynos_cpu_boot(int cpu)
66 {
67 	/*
68 	 * Exynos3250 doesn't need to send smc command for secondary CPU boot
69 	 * because Exynos3250 removes WFE in secure mode.
70 	 */
71 	if (soc_is_exynos3250())
72 		return 0;
73 
74 	/*
75 	 * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
76 	 * But, Exynos4212 has only one secondary CPU so second parameter
77 	 * isn't used for informing secure firmware about CPU id.
78 	 */
79 	if (soc_is_exynos4212())
80 		cpu = 0;
81 
82 	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
83 	return 0;
84 }
85 
86 static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
87 {
88 	void __iomem *boot_reg;
89 
90 	if (!sysram_ns_base_addr)
91 		return -ENODEV;
92 
93 	boot_reg = sysram_ns_base_addr + 0x1c;
94 
95 	/*
96 	 * Almost all Exynos-series of SoCs that run in secure mode don't need
97 	 * additional offset for every CPU, with Exynos4412 being the only
98 	 * exception.
99 	 */
100 	if (soc_is_exynos4412())
101 		boot_reg += 4 * cpu;
102 
103 	__raw_writel(boot_addr, boot_reg);
104 	return 0;
105 }
106 
107 static int exynos_cpu_suspend(unsigned long arg)
108 {
109 	flush_cache_all();
110 	outer_flush_all();
111 
112 	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
113 
114 	pr_info("Failed to suspend the system\n");
115 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
116 	return 1;
117 }
118 
119 static int exynos_suspend(void)
120 {
121 	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
122 		exynos_save_cp15();
123 
124 	writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
125 	writel(virt_to_phys(exynos_cpu_resume_ns),
126 		sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
127 
128 	return cpu_suspend(0, exynos_cpu_suspend);
129 }
130 
131 static int exynos_resume(void)
132 {
133 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
134 
135 	return 0;
136 }
137 
138 static const struct firmware_ops exynos_firmware_ops = {
139 	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
140 	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
141 	.cpu_boot		= exynos_cpu_boot,
142 	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
143 	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
144 };
145 
146 static void exynos_l2_write_sec(unsigned long val, unsigned reg)
147 {
148 	static int l2cache_enabled;
149 
150 	switch (reg) {
151 	case L2X0_CTRL:
152 		if (val & L2X0_CTRL_EN) {
153 			/*
154 			 * Before the cache can be enabled, due to firmware
155 			 * design, SMC_CMD_L2X0INVALL must be called.
156 			 */
157 			if (!l2cache_enabled) {
158 				exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
159 				l2cache_enabled = 1;
160 			}
161 		} else {
162 			l2cache_enabled = 0;
163 		}
164 		exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
165 		break;
166 
167 	case L2X0_DEBUG_CTRL:
168 		exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
169 		break;
170 
171 	default:
172 		WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
173 	}
174 }
175 
176 static void exynos_l2_configure(const struct l2x0_regs *regs)
177 {
178 	exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
179 		   regs->prefetch_ctrl);
180 	exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
181 }
182 
183 void __init exynos_firmware_init(void)
184 {
185 	struct device_node *nd;
186 	const __be32 *addr;
187 
188 	nd = of_find_compatible_node(NULL, NULL,
189 					"samsung,secure-firmware");
190 	if (!nd)
191 		return;
192 
193 	addr = of_get_address(nd, 0, NULL, NULL);
194 	if (!addr) {
195 		pr_err("%s: No address specified.\n", __func__);
196 		return;
197 	}
198 
199 	pr_info("Running under secure firmware.\n");
200 
201 	register_firmware_ops(&exynos_firmware_ops);
202 
203 	/*
204 	 * Exynos 4 SoCs (based on Cortex A9 and equipped with L2C-310),
205 	 * running under secure firmware, require certain registers of L2
206 	 * cache controller to be written in secure mode. Here .write_sec
207 	 * callback is provided to perform necessary SMC calls.
208 	 */
209 	if (IS_ENABLED(CONFIG_CACHE_L2X0) &&
210 	    read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
211 		outer_cache.write_sec = exynos_l2_write_sec;
212 		outer_cache.configure = exynos_l2_configure;
213 	}
214 }
215 
216 #define REG_CPU_STATE_ADDR	(sysram_ns_base_addr + 0x28)
217 #define BOOT_MODE_MASK		0x1f
218 
219 void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
220 {
221 	unsigned int tmp;
222 
223 	tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
224 
225 	if (mode & BOOT_MODE_MASK)
226 		tmp &= ~BOOT_MODE_MASK;
227 
228 	tmp |= mode;
229 	__raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
230 }
231 
232 void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
233 {
234 	unsigned int tmp;
235 
236 	tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
237 	tmp &= ~mode;
238 	__raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
239 }
240