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	 * On Exynos5 devices the call is ignored by trustzone firmware.
65	 */
66	if (!soc_is_exynos4210() && !soc_is_exynos4212() &&
67	    !soc_is_exynos4412())
68		return 0;
69
70	/*
71	 * The second parameter of SMC_CMD_CPU1BOOT command means CPU id.
72	 * But, Exynos4212 has only one secondary CPU so second parameter
73	 * isn't used for informing secure firmware about CPU id.
74	 */
75	if (soc_is_exynos4212())
76		cpu = 0;
77
78	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
79	return 0;
80}
81
82static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
83{
84	void __iomem *boot_reg;
85
86	if (!sysram_ns_base_addr)
87		return -ENODEV;
88
89	boot_reg = sysram_ns_base_addr + 0x1c;
90
91	/*
92	 * Almost all Exynos-series of SoCs that run in secure mode don't need
93	 * additional offset for every CPU, with Exynos4412 being the only
94	 * exception.
95	 */
96	if (soc_is_exynos4412())
97		boot_reg += 4 * cpu;
98
99	writel_relaxed(boot_addr, boot_reg);
100	return 0;
101}
102
103static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
104{
105	void __iomem *boot_reg;
106
107	if (!sysram_ns_base_addr)
108		return -ENODEV;
109
110	boot_reg = sysram_ns_base_addr + 0x1c;
111
112	if (soc_is_exynos4412())
113		boot_reg += 4 * cpu;
114
115	*boot_addr = readl_relaxed(boot_reg);
116	return 0;
117}
118
119static int exynos_cpu_suspend(unsigned long arg)
120{
121	flush_cache_all();
122	outer_flush_all();
123
124	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
125
126	pr_info("Failed to suspend the system\n");
127	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
128	return 1;
129}
130
131static int exynos_suspend(void)
132{
133	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
134		exynos_save_cp15();
135
136	writel(EXYNOS_SLEEP_MAGIC, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
137	writel(__pa_symbol(exynos_cpu_resume_ns),
138		sysram_ns_base_addr + EXYNOS_BOOT_ADDR);
139
140	return cpu_suspend(0, exynos_cpu_suspend);
141}
142
143static int exynos_resume(void)
144{
145	writel(0, sysram_ns_base_addr + EXYNOS_BOOT_FLAG);
146
147	return 0;
148}
149
150static const struct firmware_ops exynos_firmware_ops = {
151	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
152	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
153	.get_cpu_boot_addr	= exynos_get_cpu_boot_addr,
154	.cpu_boot		= exynos_cpu_boot,
155	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
156	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,
157};
158
159static void exynos_l2_write_sec(unsigned long val, unsigned reg)
160{
161	static int l2cache_enabled;
162
163	switch (reg) {
164	case L2X0_CTRL:
165		if (val & L2X0_CTRL_EN) {
166			/*
167			 * Before the cache can be enabled, due to firmware
168			 * design, SMC_CMD_L2X0INVALL must be called.
169			 */
170			if (!l2cache_enabled) {
171				exynos_smc(SMC_CMD_L2X0INVALL, 0, 0, 0);
172				l2cache_enabled = 1;
173			}
174		} else {
175			l2cache_enabled = 0;
176		}
177		exynos_smc(SMC_CMD_L2X0CTRL, val, 0, 0);
178		break;
179
180	case L2X0_DEBUG_CTRL:
181		exynos_smc(SMC_CMD_L2X0DEBUG, val, 0, 0);
182		break;
183
184	default:
185		WARN_ONCE(1, "%s: ignoring write to reg 0x%x\n", __func__, reg);
186	}
187}
188
189static void exynos_l2_configure(const struct l2x0_regs *regs)
190{
191	exynos_smc(SMC_CMD_L2X0SETUP1, regs->tag_latency, regs->data_latency,
192		   regs->prefetch_ctrl);
193	exynos_smc(SMC_CMD_L2X0SETUP2, regs->pwr_ctrl, regs->aux_ctrl, 0);
194}
195
196bool __init exynos_secure_firmware_available(void)
197{
198	struct device_node *nd;
199	const __be32 *addr;
200
201	nd = of_find_compatible_node(NULL, NULL,
202					"samsung,secure-firmware");
203	if (!nd)
204		return false;
205
206	addr = of_get_address(nd, 0, NULL, NULL);
207	of_node_put(nd);
208	if (!addr) {
209		pr_err("%s: No address specified.\n", __func__);
210		return false;
211	}
212
213	return true;
214}
215
216void __init exynos_firmware_init(void)
217{
218	if (!exynos_secure_firmware_available())
219		return;
220
221	pr_info("Running under secure firmware.\n");
222
223	register_firmware_ops(&exynos_firmware_ops);
224
225	/*
226	 * Exynos 4 SoCs (based on Cortex A9 and equipped with L2C-310),
227	 * running under secure firmware, require certain registers of L2
228	 * cache controller to be written in secure mode. Here .write_sec
229	 * callback is provided to perform necessary SMC calls.
230	 */
231	if (IS_ENABLED(CONFIG_CACHE_L2X0) &&
232	    read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) {
233		outer_cache.write_sec = exynos_l2_write_sec;
234		outer_cache.configure = exynos_l2_configure;
235	}
236}
237
238#define REG_CPU_STATE_ADDR	(sysram_ns_base_addr + 0x28)
239#define BOOT_MODE_MASK		0x1f
240
241void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
242{
243	unsigned int tmp;
244
245	tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
246
247	if (mode & BOOT_MODE_MASK)
248		tmp &= ~BOOT_MODE_MASK;
249
250	tmp |= mode;
251	writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
252}
253
254void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
255{
256	unsigned int tmp;
257
258	tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
259	tmp &= ~mode;
260	writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
261}
262