xref: /openbmc/linux/arch/arm/mach-exynos/firmware.c (revision 1edd0337)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2012 Samsung Electronics.
4 // Kyungmin Park <kyungmin.park@samsung.com>
5 // Tomasz Figa <t.figa@samsung.com>
6 
7 #include <linux/kernel.h>
8 #include <linux/io.h>
9 #include <linux/init.h>
10 #include <linux/of.h>
11 #include <linux/of_address.h>
12 
13 #include <asm/cacheflush.h>
14 #include <asm/cputype.h>
15 #include <asm/firmware.h>
16 #include <asm/hardware/cache-l2x0.h>
17 #include <asm/suspend.h>
18 
19 #include "common.h"
20 #include "smc.h"
21 
22 #define EXYNOS_BOOT_ADDR	0x8
23 #define EXYNOS_BOOT_FLAG	0xc
24 
25 static void exynos_save_cp15(void)
26 {
27 	/* Save Power control and Diagnostic registers */
28 	asm ("mrc p15, 0, %0, c15, c0, 0\n"
29 	     "mrc p15, 0, %1, c15, c0, 1\n"
30 	     : "=r" (cp15_save_power), "=r" (cp15_save_diag)
31 	     : : "cc");
32 }
33 
34 static int exynos_do_idle(unsigned long mode)
35 {
36 	switch (mode) {
37 	case FW_DO_IDLE_AFTR:
38 		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
39 			exynos_save_cp15();
40 		writel_relaxed(__pa_symbol(exynos_cpu_resume_ns),
41 			       sysram_ns_base_addr + 0x24);
42 		writel_relaxed(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
43 		if (soc_is_exynos3250()) {
44 			flush_cache_all();
45 			exynos_smc(SMC_CMD_SAVE, OP_TYPE_CORE,
46 				   SMC_POWERSTATE_IDLE, 0);
47 			exynos_smc(SMC_CMD_SHUTDOWN, OP_TYPE_CLUSTER,
48 				   SMC_POWERSTATE_IDLE, 0);
49 		} else
50 			exynos_smc(SMC_CMD_CPU0AFTR, 0, 0, 0);
51 		break;
52 	case FW_DO_IDLE_SLEEP:
53 		exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
54 	}
55 	return 0;
56 }
57 
58 static int exynos_cpu_boot(int cpu)
59 {
60 	/*
61 	 * Exynos3250 doesn't need to send smc command for secondary CPU boot
62 	 * because Exynos3250 removes WFE in secure mode.
63 	 *
64 	 * On Exynos5 devices the call is ignored by trustzone firmware.
65 	 */
66 	if (!soc_is_exynos4210() && !soc_is_exynos4412())
67 		return 0;
68 
69 	/*
70 	 * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
71 	 */
72 	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
73 	return 0;
74 }
75 
76 static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
77 {
78 	void __iomem *boot_reg;
79 
80 	if (!sysram_ns_base_addr)
81 		return -ENODEV;
82 
83 	boot_reg = sysram_ns_base_addr + 0x1c;
84 
85 	/*
86 	 * Almost all Exynos-series of SoCs that run in secure mode don't need
87 	 * additional offset for every CPU, with Exynos4412 being the only
88 	 * exception.
89 	 */
90 	if (soc_is_exynos4412())
91 		boot_reg += 4 * cpu;
92 
93 	writel_relaxed(boot_addr, boot_reg);
94 	return 0;
95 }
96 
97 static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
98 {
99 	void __iomem *boot_reg;
100 
101 	if (!sysram_ns_base_addr)
102 		return -ENODEV;
103 
104 	boot_reg = sysram_ns_base_addr + 0x1c;
105 
106 	if (soc_is_exynos4412())
107 		boot_reg += 4 * cpu;
108 
109 	*boot_addr = readl_relaxed(boot_reg);
110 	return 0;
111 }
112 
113 static int exynos_cpu_suspend(unsigned long arg)
114 {
115 	flush_cache_all();
116 	outer_flush_all();
117 
118 	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
119 
120 	pr_info("Failed to suspend the system\n");
121 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
122 	return 1;
123 }
124 
125 static int exynos_suspend(void)
126 {
127 	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
128 		exynos_save_cp15();
129 
130 	writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
131 	writel(__pa_symbol(exynos_cpu_resume_ns),
132 		sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
133 
134 	return cpu_suspend(0, exynos_cpu_suspend);
135 }
136 
137 static int exynos_resume(void)
138 {
139 	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
140 
141 	return 0;
142 }
143 
144 static const struct firmware_ops exynos_firmware_ops = {
145 	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
146 	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
147 	.get_cpu_boot_addr	= exynos_get_cpu_boot_addr,
148 	.cpu_boot		= exynos_cpu_boot,
149 	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
150 	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
151 };
152 
153 static void exynos_l2_write_sec(unsigned long val, unsigned reg)
154 {
155 	static int l2cache_enabled;
156 
157 	switch (reg) {
158 	case L2X0_CTRL:
159 		if (val & L2X0_CTRL_EN) {
160 			/*
161 			 * Before the cache can be enabled, due to firmware
162 			 * design, SMC_CMD_L2X0INVALL must be called.
163 			 */
164 			if (!l2cache_enabled) {
165 				exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
166 				l2cache_enabled = 1;
167 			}
168 		} else {
169 			l2cache_enabled = 0;
170 		}
171 		exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
172 		break;
173 
174 	case L2X0_DEBUG_CTRL:
175 		exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
176 		break;
177 
178 	default:
179 		WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
180 	}
181 }
182 
183 static void exynos_l2_configure(const struct l2x0_regs *regs)
184 {
185 	exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
186 		   regs->prefetch_ctrl);
187 	exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
188 }
189 
190 bool __init exynos_secure_firmware_available(void)
191 {
192 	struct device_node *nd;
193 	const __be32 *addr;
194 
195 	nd = of_find_compatible_node(NULL, NULL,
196 					"samsung,secure-firmware");
197 	if (!nd)
198 		return false;
199 
200 	addr = of_get_address(nd, 0, NULL, NULL);
201 	of_node_put(nd);
202 	if (!addr) {
203 		pr_err("%s: No address specified.\n", __func__);
204 		return false;
205 	}
206 
207 	return true;
208 }
209 
210 void __init exynos_firmware_init(void)
211 {
212 	if (!exynos_secure_firmware_available())
213 		return;
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 = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
240 
241 	if (mode & BOOT_MODE_MASK)
242 		tmp &= ~BOOT_MODE_MASK;
243 
244 	tmp |= mode;
245 	writel_relaxed(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 = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
253 	tmp &= ~mode;
254 	writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
255 }
256