xref: /openbmc/linux/arch/arm/mach-qcom/platsmp.c (revision bc5aa3a0)
1 /*
2  *  Copyright (C) 2002 ARM Ltd.
3  *  All Rights Reserved
4  *  Copyright (c) 2010, Code Aurora Forum. All rights reserved.
5  *  Copyright (c) 2014 The Linux Foundation. All rights reserved.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/init.h>
13 #include <linux/errno.h>
14 #include <linux/delay.h>
15 #include <linux/device.h>
16 #include <linux/of.h>
17 #include <linux/of_address.h>
18 #include <linux/smp.h>
19 #include <linux/io.h>
20 #include <linux/qcom_scm.h>
21 
22 #include <asm/smp_plat.h>
23 
24 
25 #define VDD_SC1_ARRAY_CLAMP_GFS_CTL	0x35a0
26 #define SCSS_CPU1CORE_RESET		0x2d80
27 #define SCSS_DBG_STATUS_CORE_PWRDUP	0x2e64
28 
29 #define APCS_CPU_PWR_CTL	0x04
30 #define PLL_CLAMP		BIT(8)
31 #define CORE_PWRD_UP		BIT(7)
32 #define COREPOR_RST		BIT(5)
33 #define CORE_RST		BIT(4)
34 #define L2DT_SLP		BIT(3)
35 #define CLAMP			BIT(0)
36 
37 #define APC_PWR_GATE_CTL	0x14
38 #define BHS_CNT_SHIFT		24
39 #define LDO_PWR_DWN_SHIFT	16
40 #define LDO_BYP_SHIFT		8
41 #define BHS_SEG_SHIFT		1
42 #define BHS_EN			BIT(0)
43 
44 #define APCS_SAW2_VCTL		0x14
45 #define APCS_SAW2_2_VCTL	0x1c
46 
47 extern void secondary_startup_arm(void);
48 
49 static DEFINE_SPINLOCK(boot_lock);
50 
51 #ifdef CONFIG_HOTPLUG_CPU
52 static void qcom_cpu_die(unsigned int cpu)
53 {
54 	wfi();
55 }
56 #endif
57 
58 static void qcom_secondary_init(unsigned int cpu)
59 {
60 	/*
61 	 * Synchronise with the boot thread.
62 	 */
63 	spin_lock(&boot_lock);
64 	spin_unlock(&boot_lock);
65 }
66 
67 static int scss_release_secondary(unsigned int cpu)
68 {
69 	struct device_node *node;
70 	void __iomem *base;
71 
72 	node = of_find_compatible_node(NULL, NULL, "qcom,gcc-msm8660");
73 	if (!node) {
74 		pr_err("%s: can't find node\n", __func__);
75 		return -ENXIO;
76 	}
77 
78 	base = of_iomap(node, 0);
79 	of_node_put(node);
80 	if (!base)
81 		return -ENOMEM;
82 
83 	writel_relaxed(0, base + VDD_SC1_ARRAY_CLAMP_GFS_CTL);
84 	writel_relaxed(0, base + SCSS_CPU1CORE_RESET);
85 	writel_relaxed(3, base + SCSS_DBG_STATUS_CORE_PWRDUP);
86 	mb();
87 	iounmap(base);
88 
89 	return 0;
90 }
91 
92 static int kpssv1_release_secondary(unsigned int cpu)
93 {
94 	int ret = 0;
95 	void __iomem *reg, *saw_reg;
96 	struct device_node *cpu_node, *acc_node, *saw_node;
97 	u32 val;
98 
99 	cpu_node = of_get_cpu_node(cpu, NULL);
100 	if (!cpu_node)
101 		return -ENODEV;
102 
103 	acc_node = of_parse_phandle(cpu_node, "qcom,acc", 0);
104 	if (!acc_node) {
105 		ret = -ENODEV;
106 		goto out_acc;
107 	}
108 
109 	saw_node = of_parse_phandle(cpu_node, "qcom,saw", 0);
110 	if (!saw_node) {
111 		ret = -ENODEV;
112 		goto out_saw;
113 	}
114 
115 	reg = of_iomap(acc_node, 0);
116 	if (!reg) {
117 		ret = -ENOMEM;
118 		goto out_acc_map;
119 	}
120 
121 	saw_reg = of_iomap(saw_node, 0);
122 	if (!saw_reg) {
123 		ret = -ENOMEM;
124 		goto out_saw_map;
125 	}
126 
127 	/* Turn on CPU rail */
128 	writel_relaxed(0xA4, saw_reg + APCS_SAW2_VCTL);
129 	mb();
130 	udelay(512);
131 
132 	/* Krait bring-up sequence */
133 	val = PLL_CLAMP | L2DT_SLP | CLAMP;
134 	writel_relaxed(val, reg + APCS_CPU_PWR_CTL);
135 	val &= ~L2DT_SLP;
136 	writel_relaxed(val, reg + APCS_CPU_PWR_CTL);
137 	mb();
138 	ndelay(300);
139 
140 	val |= COREPOR_RST;
141 	writel_relaxed(val, reg + APCS_CPU_PWR_CTL);
142 	mb();
143 	udelay(2);
144 
145 	val &= ~CLAMP;
146 	writel_relaxed(val, reg + APCS_CPU_PWR_CTL);
147 	mb();
148 	udelay(2);
149 
150 	val &= ~COREPOR_RST;
151 	writel_relaxed(val, reg + APCS_CPU_PWR_CTL);
152 	mb();
153 	udelay(100);
154 
155 	val |= CORE_PWRD_UP;
156 	writel_relaxed(val, reg + APCS_CPU_PWR_CTL);
157 	mb();
158 
159 	iounmap(saw_reg);
160 out_saw_map:
161 	iounmap(reg);
162 out_acc_map:
163 	of_node_put(saw_node);
164 out_saw:
165 	of_node_put(acc_node);
166 out_acc:
167 	of_node_put(cpu_node);
168 	return ret;
169 }
170 
171 static int kpssv2_release_secondary(unsigned int cpu)
172 {
173 	void __iomem *reg;
174 	struct device_node *cpu_node, *l2_node, *acc_node, *saw_node;
175 	void __iomem *l2_saw_base;
176 	unsigned reg_val;
177 	int ret;
178 
179 	cpu_node = of_get_cpu_node(cpu, NULL);
180 	if (!cpu_node)
181 		return -ENODEV;
182 
183 	acc_node = of_parse_phandle(cpu_node, "qcom,acc", 0);
184 	if (!acc_node) {
185 		ret = -ENODEV;
186 		goto out_acc;
187 	}
188 
189 	l2_node = of_parse_phandle(cpu_node, "next-level-cache", 0);
190 	if (!l2_node) {
191 		ret = -ENODEV;
192 		goto out_l2;
193 	}
194 
195 	saw_node = of_parse_phandle(l2_node, "qcom,saw", 0);
196 	if (!saw_node) {
197 		ret = -ENODEV;
198 		goto out_saw;
199 	}
200 
201 	reg = of_iomap(acc_node, 0);
202 	if (!reg) {
203 		ret = -ENOMEM;
204 		goto out_map;
205 	}
206 
207 	l2_saw_base = of_iomap(saw_node, 0);
208 	if (!l2_saw_base) {
209 		ret = -ENOMEM;
210 		goto out_saw_map;
211 	}
212 
213 	/* Turn on the BHS, turn off LDO Bypass and power down LDO */
214 	reg_val = (64 << BHS_CNT_SHIFT) | (0x3f << LDO_PWR_DWN_SHIFT) | BHS_EN;
215 	writel_relaxed(reg_val, reg + APC_PWR_GATE_CTL);
216 	mb();
217 	/* wait for the BHS to settle */
218 	udelay(1);
219 
220 	/* Turn on BHS segments */
221 	reg_val |= 0x3f << BHS_SEG_SHIFT;
222 	writel_relaxed(reg_val, reg + APC_PWR_GATE_CTL);
223 	mb();
224 	 /* wait for the BHS to settle */
225 	udelay(1);
226 
227 	/* Finally turn on the bypass so that BHS supplies power */
228 	reg_val |= 0x3f << LDO_BYP_SHIFT;
229 	writel_relaxed(reg_val, reg + APC_PWR_GATE_CTL);
230 
231 	/* enable max phases */
232 	writel_relaxed(0x10003, l2_saw_base + APCS_SAW2_2_VCTL);
233 	mb();
234 	udelay(50);
235 
236 	reg_val = COREPOR_RST | CLAMP;
237 	writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
238 	mb();
239 	udelay(2);
240 
241 	reg_val &= ~CLAMP;
242 	writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
243 	mb();
244 	udelay(2);
245 
246 	reg_val &= ~COREPOR_RST;
247 	writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
248 	mb();
249 
250 	reg_val |= CORE_PWRD_UP;
251 	writel_relaxed(reg_val, reg + APCS_CPU_PWR_CTL);
252 	mb();
253 
254 	ret = 0;
255 
256 	iounmap(l2_saw_base);
257 out_saw_map:
258 	iounmap(reg);
259 out_map:
260 	of_node_put(saw_node);
261 out_saw:
262 	of_node_put(l2_node);
263 out_l2:
264 	of_node_put(acc_node);
265 out_acc:
266 	of_node_put(cpu_node);
267 
268 	return ret;
269 }
270 
271 static DEFINE_PER_CPU(int, cold_boot_done);
272 
273 static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int))
274 {
275 	int ret = 0;
276 
277 	if (!per_cpu(cold_boot_done, cpu)) {
278 		ret = func(cpu);
279 		if (!ret)
280 			per_cpu(cold_boot_done, cpu) = true;
281 	}
282 
283 	/*
284 	 * set synchronisation state between this boot processor
285 	 * and the secondary one
286 	 */
287 	spin_lock(&boot_lock);
288 
289 	/*
290 	 * Send the secondary CPU a soft interrupt, thereby causing
291 	 * the boot monitor to read the system wide flags register,
292 	 * and branch to the address found there.
293 	 */
294 	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
295 
296 	/*
297 	 * now the secondary core is starting up let it run its
298 	 * calibrations, then wait for it to finish
299 	 */
300 	spin_unlock(&boot_lock);
301 
302 	return ret;
303 }
304 
305 static int msm8660_boot_secondary(unsigned int cpu, struct task_struct *idle)
306 {
307 	return qcom_boot_secondary(cpu, scss_release_secondary);
308 }
309 
310 static int kpssv1_boot_secondary(unsigned int cpu, struct task_struct *idle)
311 {
312 	return qcom_boot_secondary(cpu, kpssv1_release_secondary);
313 }
314 
315 static int kpssv2_boot_secondary(unsigned int cpu, struct task_struct *idle)
316 {
317 	return qcom_boot_secondary(cpu, kpssv2_release_secondary);
318 }
319 
320 static void __init qcom_smp_prepare_cpus(unsigned int max_cpus)
321 {
322 	int cpu;
323 
324 	if (qcom_scm_set_cold_boot_addr(secondary_startup_arm,
325 					cpu_present_mask)) {
326 		for_each_present_cpu(cpu) {
327 			if (cpu == smp_processor_id())
328 				continue;
329 			set_cpu_present(cpu, false);
330 		}
331 		pr_warn("Failed to set CPU boot address, disabling SMP\n");
332 	}
333 }
334 
335 static const struct smp_operations smp_msm8660_ops __initconst = {
336 	.smp_prepare_cpus	= qcom_smp_prepare_cpus,
337 	.smp_secondary_init	= qcom_secondary_init,
338 	.smp_boot_secondary	= msm8660_boot_secondary,
339 #ifdef CONFIG_HOTPLUG_CPU
340 	.cpu_die		= qcom_cpu_die,
341 #endif
342 };
343 CPU_METHOD_OF_DECLARE(qcom_smp, "qcom,gcc-msm8660", &smp_msm8660_ops);
344 
345 static const struct smp_operations qcom_smp_kpssv1_ops __initconst = {
346 	.smp_prepare_cpus	= qcom_smp_prepare_cpus,
347 	.smp_secondary_init	= qcom_secondary_init,
348 	.smp_boot_secondary	= kpssv1_boot_secondary,
349 #ifdef CONFIG_HOTPLUG_CPU
350 	.cpu_die		= qcom_cpu_die,
351 #endif
352 };
353 CPU_METHOD_OF_DECLARE(qcom_smp_kpssv1, "qcom,kpss-acc-v1", &qcom_smp_kpssv1_ops);
354 
355 static const struct smp_operations qcom_smp_kpssv2_ops __initconst = {
356 	.smp_prepare_cpus	= qcom_smp_prepare_cpus,
357 	.smp_secondary_init	= qcom_secondary_init,
358 	.smp_boot_secondary	= kpssv2_boot_secondary,
359 #ifdef CONFIG_HOTPLUG_CPU
360 	.cpu_die		= qcom_cpu_die,
361 #endif
362 };
363 CPU_METHOD_OF_DECLARE(qcom_smp_kpssv2, "qcom,kpss-acc-v2", &qcom_smp_kpssv2_ops);
364