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
25static 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
34static 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
58static 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	if (soc_is_exynos3250())
65		return 0;
66
67	/*
68	 * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
69	 */
70	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
71	return 0;
72}
73
74static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
75{
76	void __iomem *boot_reg;
77
78	if (!sysram_ns_base_addr)
79		return -ENODEV;
80
81	boot_reg = sysram_ns_base_addr + 0x1c;
82
83	/*
84	 * Almost all Exynos-series of SoCs that run in secure mode don't need
85	 * additional offset for every CPU, with Exynos4412 being the only
86	 * exception.
87	 */
88	if (soc_is_exynos4412())
89		boot_reg += 4 * cpu;
90
91	writel_relaxed(boot_addr, boot_reg);
92	return 0;
93}
94
95static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
96{
97	void __iomem *boot_reg;
98
99	if (!sysram_ns_base_addr)
100		return -ENODEV;
101
102	boot_reg = sysram_ns_base_addr + 0x1c;
103
104	if (soc_is_exynos4412())
105		boot_reg += 4 * cpu;
106
107	*boot_addr = readl_relaxed(boot_reg);
108	return 0;
109}
110
111static int exynos_cpu_suspend(unsigned long arg)
112{
113	flush_cache_all();
114	outer_flush_all();
115
116	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
117
118	pr_info("Failed to suspend the system\n");
119	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
120	return 1;
121}
122
123static int exynos_suspend(void)
124{
125	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
126		exynos_save_cp15();
127
128	writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
129	writel(__pa_symbol(exynos_cpu_resume_ns),
130		sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
131
132	return cpu_suspend(0, exynos_cpu_suspend);
133}
134
135static int exynos_resume(void)
136{
137	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
138
139	return 0;
140}
141
142static const struct firmware_ops exynos_firmware_ops = {
143	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
144	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
145	.get_cpu_boot_addr	= exynos_get_cpu_boot_addr,
146	.cpu_boot		= exynos_cpu_boot,
147	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
148	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
149};
150
151static void exynos_l2_write_sec(unsigned long val, unsigned reg)
152{
153	static int l2cache_enabled;
154
155	switch (reg) {
156	case L2X0_CTRL:
157		if (val & L2X0_CTRL_EN) {
158			/*
159			 * Before the cache can be enabled, due to firmware
160			 * design, SMC_CMD_L2X0INVALL must be called.
161			 */
162			if (!l2cache_enabled) {
163				exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
164				l2cache_enabled = 1;
165			}
166		} else {
167			l2cache_enabled = 0;
168		}
169		exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
170		break;
171
172	case L2X0_DEBUG_CTRL:
173		exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
174		break;
175
176	default:
177		WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
178	}
179}
180
181static void exynos_l2_configure(const struct l2x0_regs *regs)
182{
183	exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
184		   regs->prefetch_ctrl);
185	exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
186}
187
188bool __init exynos_secure_firmware_available(void)
189{
190	struct device_node *nd;
191	const __be32 *addr;
192
193	nd = of_find_compatible_node(NULL, NULL,
194					"samsung,secure-firmware");
195	if (!nd)
196		return false;
197
198	addr = of_get_address(nd, 0, NULL, NULL);
199	of_node_put(nd);
200	if (!addr) {
201		pr_err("%s: No address specified.\n", __func__);
202		return false;
203	}
204
205	return true;
206}
207
208void __init exynos_firmware_init(void)
209{
210	if (!exynos_secure_firmware_available())
211		return;
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
233void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
234{
235	unsigned int tmp;
236
237	tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
238
239	if (mode & BOOT_MODE_MASK)
240		tmp &= ~BOOT_MODE_MASK;
241
242	tmp |= mode;
243	writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
244}
245
246void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
247{
248	unsigned int tmp;
249
250	tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
251	tmp &= ~mode;
252	writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
253}
254