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
47extern void secondary_startup_arm(void);
48
49static DEFINE_SPINLOCK(boot_lock);
50
51#ifdef CONFIG_HOTPLUG_CPU
52static void qcom_cpu_die(unsigned int cpu)
53{
54	wfi();
55}
56#endif
57
58static 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
67static 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
92static 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);
160out_saw_map:
161	iounmap(reg);
162out_acc_map:
163	of_node_put(saw_node);
164out_saw:
165	of_node_put(acc_node);
166out_acc:
167	of_node_put(cpu_node);
168	return ret;
169}
170
171static 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);
257out_saw_map:
258	iounmap(reg);
259out_map:
260	of_node_put(saw_node);
261out_saw:
262	of_node_put(l2_node);
263out_l2:
264	of_node_put(acc_node);
265out_acc:
266	of_node_put(cpu_node);
267
268	return ret;
269}
270
271static DEFINE_PER_CPU(int, cold_boot_done);
272
273static 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
305static int msm8660_boot_secondary(unsigned int cpu, struct task_struct *idle)
306{
307	return qcom_boot_secondary(cpu, scss_release_secondary);
308}
309
310static int kpssv1_boot_secondary(unsigned int cpu, struct task_struct *idle)
311{
312	return qcom_boot_secondary(cpu, kpssv1_release_secondary);
313}
314
315static int kpssv2_boot_secondary(unsigned int cpu, struct task_struct *idle)
316{
317	return qcom_boot_secondary(cpu, kpssv2_release_secondary);
318}
319
320static 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
335static struct smp_operations smp_msm8660_ops __initdata = {
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};
343CPU_METHOD_OF_DECLARE(qcom_smp, "qcom,gcc-msm8660", &smp_msm8660_ops);
344
345static struct smp_operations qcom_smp_kpssv1_ops __initdata = {
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};
353CPU_METHOD_OF_DECLARE(qcom_smp_kpssv1, "qcom,kpss-acc-v1", &qcom_smp_kpssv1_ops);
354
355static struct smp_operations qcom_smp_kpssv2_ops __initdata = {
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};
363CPU_METHOD_OF_DECLARE(qcom_smp_kpssv2, "qcom,kpss-acc-v2", &qcom_smp_kpssv2_ops);
364