xref: /openbmc/linux/arch/arm/mach-hisi/platmcpm.c (revision f7d84fa7)
1 /*
2  * Copyright (c) 2013-2014 Linaro Ltd.
3  * Copyright (c) 2013-2014 Hisilicon Limited.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  */
9 #include <linux/init.h>
10 #include <linux/smp.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13 #include <linux/memblock.h>
14 #include <linux/of_address.h>
15 
16 #include <asm/cputype.h>
17 #include <asm/cp15.h>
18 #include <asm/cacheflush.h>
19 #include <asm/smp.h>
20 #include <asm/smp_plat.h>
21 
22 #include "core.h"
23 
24 /* bits definition in SC_CPU_RESET_REQ[x]/SC_CPU_RESET_DREQ[x]
25  * 1 -- unreset; 0 -- reset
26  */
27 #define CORE_RESET_BIT(x)		(1 << x)
28 #define NEON_RESET_BIT(x)		(1 << (x + 4))
29 #define CORE_DEBUG_RESET_BIT(x)		(1 << (x + 9))
30 #define CLUSTER_L2_RESET_BIT		(1 << 8)
31 #define CLUSTER_DEBUG_RESET_BIT		(1 << 13)
32 
33 /*
34  * bits definition in SC_CPU_RESET_STATUS[x]
35  * 1 -- reset status; 0 -- unreset status
36  */
37 #define CORE_RESET_STATUS(x)		(1 << x)
38 #define NEON_RESET_STATUS(x)		(1 << (x + 4))
39 #define CORE_DEBUG_RESET_STATUS(x)	(1 << (x + 9))
40 #define CLUSTER_L2_RESET_STATUS		(1 << 8)
41 #define CLUSTER_DEBUG_RESET_STATUS	(1 << 13)
42 #define CORE_WFI_STATUS(x)		(1 << (x + 16))
43 #define CORE_WFE_STATUS(x)		(1 << (x + 20))
44 #define CORE_DEBUG_ACK(x)		(1 << (x + 24))
45 
46 #define SC_CPU_RESET_REQ(x)		(0x520 + (x << 3))	/* reset */
47 #define SC_CPU_RESET_DREQ(x)		(0x524 + (x << 3))	/* unreset */
48 #define SC_CPU_RESET_STATUS(x)		(0x1520 + (x << 3))
49 
50 #define FAB_SF_MODE			0x0c
51 #define FAB_SF_INVLD			0x10
52 
53 /* bits definition in FB_SF_INVLD */
54 #define FB_SF_INVLD_START		(1 << 8)
55 
56 #define HIP04_MAX_CLUSTERS		4
57 #define HIP04_MAX_CPUS_PER_CLUSTER	4
58 
59 #define POLL_MSEC	10
60 #define TIMEOUT_MSEC	1000
61 
62 static void __iomem *sysctrl, *fabric;
63 static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER];
64 static DEFINE_SPINLOCK(boot_lock);
65 static u32 fabric_phys_addr;
66 /*
67  * [0]: bootwrapper physical address
68  * [1]: bootwrapper size
69  * [2]: relocation address
70  * [3]: relocation size
71  */
72 static u32 hip04_boot_method[4];
73 
74 static bool hip04_cluster_is_down(unsigned int cluster)
75 {
76 	int i;
77 
78 	for (i = 0; i < HIP04_MAX_CPUS_PER_CLUSTER; i++)
79 		if (hip04_cpu_table[cluster][i])
80 			return false;
81 	return true;
82 }
83 
84 static void hip04_set_snoop_filter(unsigned int cluster, unsigned int on)
85 {
86 	unsigned long data;
87 
88 	if (!fabric)
89 		BUG();
90 	data = readl_relaxed(fabric + FAB_SF_MODE);
91 	if (on)
92 		data |= 1 << cluster;
93 	else
94 		data &= ~(1 << cluster);
95 	writel_relaxed(data, fabric + FAB_SF_MODE);
96 	do {
97 		cpu_relax();
98 	} while (data != readl_relaxed(fabric + FAB_SF_MODE));
99 }
100 
101 static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
102 {
103 	unsigned int mpidr, cpu, cluster;
104 	unsigned long data;
105 	void __iomem *sys_dreq, *sys_status;
106 
107 	mpidr = cpu_logical_map(l_cpu);
108 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
109 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
110 
111 	if (!sysctrl)
112 		return -ENODEV;
113 	if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)
114 		return -EINVAL;
115 
116 	spin_lock_irq(&boot_lock);
117 
118 	if (hip04_cpu_table[cluster][cpu])
119 		goto out;
120 
121 	sys_dreq = sysctrl + SC_CPU_RESET_DREQ(cluster);
122 	sys_status = sysctrl + SC_CPU_RESET_STATUS(cluster);
123 	if (hip04_cluster_is_down(cluster)) {
124 		data = CLUSTER_DEBUG_RESET_BIT;
125 		writel_relaxed(data, sys_dreq);
126 		do {
127 			cpu_relax();
128 			data = readl_relaxed(sys_status);
129 		} while (data & CLUSTER_DEBUG_RESET_STATUS);
130 		hip04_set_snoop_filter(cluster, 1);
131 	}
132 
133 	data = CORE_RESET_BIT(cpu) | NEON_RESET_BIT(cpu) | \
134 	       CORE_DEBUG_RESET_BIT(cpu);
135 	writel_relaxed(data, sys_dreq);
136 	do {
137 		cpu_relax();
138 	} while (data == readl_relaxed(sys_status));
139 
140 	/*
141 	 * We may fail to power up core again without this delay.
142 	 * It's not mentioned in document. It's found by test.
143 	 */
144 	udelay(20);
145 
146 	arch_send_wakeup_ipi_mask(cpumask_of(l_cpu));
147 
148 out:
149 	hip04_cpu_table[cluster][cpu]++;
150 	spin_unlock_irq(&boot_lock);
151 
152 	return 0;
153 }
154 
155 #ifdef CONFIG_HOTPLUG_CPU
156 static void hip04_cpu_die(unsigned int l_cpu)
157 {
158 	unsigned int mpidr, cpu, cluster;
159 	bool last_man;
160 
161 	mpidr = cpu_logical_map(l_cpu);
162 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
163 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
164 
165 	spin_lock(&boot_lock);
166 	hip04_cpu_table[cluster][cpu]--;
167 	if (hip04_cpu_table[cluster][cpu] == 1) {
168 		/* A power_up request went ahead of us. */
169 		spin_unlock(&boot_lock);
170 		return;
171 	} else if (hip04_cpu_table[cluster][cpu] > 1) {
172 		pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
173 		BUG();
174 	}
175 
176 	last_man = hip04_cluster_is_down(cluster);
177 	spin_unlock(&boot_lock);
178 	if (last_man) {
179 		/* Since it's Cortex A15, disable L2 prefetching. */
180 		asm volatile(
181 		"mcr	p15, 1, %0, c15, c0, 3 \n\t"
182 		"isb	\n\t"
183 		"dsb	"
184 		: : "r" (0x400) );
185 		v7_exit_coherency_flush(all);
186 	} else {
187 		v7_exit_coherency_flush(louis);
188 	}
189 
190 	for (;;)
191 		wfi();
192 }
193 
194 static int hip04_cpu_kill(unsigned int l_cpu)
195 {
196 	unsigned int mpidr, cpu, cluster;
197 	unsigned int data, tries, count;
198 
199 	mpidr = cpu_logical_map(l_cpu);
200 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
201 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
202 	BUG_ON(cluster >= HIP04_MAX_CLUSTERS ||
203 	       cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
204 
205 	count = TIMEOUT_MSEC / POLL_MSEC;
206 	spin_lock_irq(&boot_lock);
207 	for (tries = 0; tries < count; tries++) {
208 		if (hip04_cpu_table[cluster][cpu])
209 			goto err;
210 		cpu_relax();
211 		data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
212 		if (data & CORE_WFI_STATUS(cpu))
213 			break;
214 		spin_unlock_irq(&boot_lock);
215 		/* Wait for clean L2 when the whole cluster is down. */
216 		msleep(POLL_MSEC);
217 		spin_lock_irq(&boot_lock);
218 	}
219 	if (tries >= count)
220 		goto err;
221 	data = CORE_RESET_BIT(cpu) | NEON_RESET_BIT(cpu) | \
222 	       CORE_DEBUG_RESET_BIT(cpu);
223 	writel_relaxed(data, sysctrl + SC_CPU_RESET_REQ(cluster));
224 	for (tries = 0; tries < count; tries++) {
225 		cpu_relax();
226 		data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
227 		if (data & CORE_RESET_STATUS(cpu))
228 			break;
229 	}
230 	if (tries >= count)
231 		goto err;
232 	if (hip04_cluster_is_down(cluster))
233 		hip04_set_snoop_filter(cluster, 0);
234 	spin_unlock_irq(&boot_lock);
235 	return 1;
236 err:
237 	spin_unlock_irq(&boot_lock);
238 	return 0;
239 }
240 #endif
241 
242 static const struct smp_operations hip04_smp_ops __initconst = {
243 	.smp_boot_secondary	= hip04_boot_secondary,
244 #ifdef CONFIG_HOTPLUG_CPU
245 	.cpu_die		= hip04_cpu_die,
246 	.cpu_kill		= hip04_cpu_kill,
247 #endif
248 };
249 
250 static bool __init hip04_cpu_table_init(void)
251 {
252 	unsigned int mpidr, cpu, cluster;
253 
254 	mpidr = read_cpuid_mpidr();
255 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
256 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
257 
258 	if (cluster >= HIP04_MAX_CLUSTERS ||
259 	    cpu >= HIP04_MAX_CPUS_PER_CLUSTER) {
260 		pr_err("%s: boot CPU is out of bound!\n", __func__);
261 		return false;
262 	}
263 	hip04_set_snoop_filter(cluster, 1);
264 	hip04_cpu_table[cluster][cpu] = 1;
265 	return true;
266 }
267 
268 static int __init hip04_smp_init(void)
269 {
270 	struct device_node *np, *np_sctl, *np_fab;
271 	struct resource fab_res;
272 	void __iomem *relocation;
273 	int ret = -ENODEV;
274 
275 	np = of_find_compatible_node(NULL, NULL, "hisilicon,hip04-bootwrapper");
276 	if (!np)
277 		goto err;
278 	ret = of_property_read_u32_array(np, "boot-method",
279 					 &hip04_boot_method[0], 4);
280 	if (ret)
281 		goto err;
282 
283 	ret = -ENODEV;
284 	np_sctl = of_find_compatible_node(NULL, NULL, "hisilicon,sysctrl");
285 	if (!np_sctl)
286 		goto err;
287 	np_fab = of_find_compatible_node(NULL, NULL, "hisilicon,hip04-fabric");
288 	if (!np_fab)
289 		goto err;
290 
291 	ret = memblock_reserve(hip04_boot_method[0], hip04_boot_method[1]);
292 	if (ret)
293 		goto err;
294 
295 	relocation = ioremap(hip04_boot_method[2], hip04_boot_method[3]);
296 	if (!relocation) {
297 		pr_err("failed to map relocation space\n");
298 		ret = -ENOMEM;
299 		goto err_reloc;
300 	}
301 	sysctrl = of_iomap(np_sctl, 0);
302 	if (!sysctrl) {
303 		pr_err("failed to get sysctrl base\n");
304 		ret = -ENOMEM;
305 		goto err_sysctrl;
306 	}
307 	ret = of_address_to_resource(np_fab, 0, &fab_res);
308 	if (ret) {
309 		pr_err("failed to get fabric base phys\n");
310 		goto err_fabric;
311 	}
312 	fabric_phys_addr = fab_res.start;
313 	sync_cache_w(&fabric_phys_addr);
314 	fabric = of_iomap(np_fab, 0);
315 	if (!fabric) {
316 		pr_err("failed to get fabric base\n");
317 		ret = -ENOMEM;
318 		goto err_fabric;
319 	}
320 
321 	if (!hip04_cpu_table_init()) {
322 		ret = -EINVAL;
323 		goto err_table;
324 	}
325 
326 	/*
327 	 * Fill the instruction address that is used after secondary core
328 	 * out of reset.
329 	 */
330 	writel_relaxed(hip04_boot_method[0], relocation);
331 	writel_relaxed(0xa5a5a5a5, relocation + 4);	/* magic number */
332 	writel_relaxed(__pa_symbol(secondary_startup), relocation + 8);
333 	writel_relaxed(0, relocation + 12);
334 	iounmap(relocation);
335 
336 	smp_set_ops(&hip04_smp_ops);
337 	return ret;
338 err_table:
339 	iounmap(fabric);
340 err_fabric:
341 	iounmap(sysctrl);
342 err_sysctrl:
343 	iounmap(relocation);
344 err_reloc:
345 	memblock_free(hip04_boot_method[0], hip04_boot_method[1]);
346 err:
347 	return ret;
348 }
349 early_initcall(hip04_smp_init);
350