xref: /openbmc/linux/arch/arm/mach-omap2/omap-smp.c (revision 4f6cce39)
1 /*
2  * OMAP4 SMP source file. It contains platform specific functions
3  * needed for the linux smp kernel.
4  *
5  * Copyright (C) 2009 Texas Instruments, Inc.
6  *
7  * Author:
8  *      Santosh Shilimkar <santosh.shilimkar@ti.com>
9  *
10  * Platform file needed for the OMAP4 SMP. This file is based on arm
11  * realview smp platform.
12  * * Copyright (c) 2002 ARM Limited.
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License version 2 as
16  * published by the Free Software Foundation.
17  */
18 #include <linux/init.h>
19 #include <linux/device.h>
20 #include <linux/smp.h>
21 #include <linux/io.h>
22 #include <linux/irqchip/arm-gic.h>
23 
24 #include <asm/smp_scu.h>
25 #include <asm/virt.h>
26 
27 #include "omap-secure.h"
28 #include "omap-wakeupgen.h"
29 #include <asm/cputype.h>
30 
31 #include "soc.h"
32 #include "iomap.h"
33 #include "common.h"
34 #include "clockdomain.h"
35 #include "pm.h"
36 
37 #define CPU_MASK		0xff0ffff0
38 #define CPU_CORTEX_A9		0x410FC090
39 #define CPU_CORTEX_A15		0x410FC0F0
40 
41 #define OMAP5_CORE_COUNT	0x2
42 
43 struct omap_smp_config {
44 	unsigned long cpu1_rstctrl_pa;
45 	void __iomem *cpu1_rstctrl_va;
46 	void __iomem *scu_base;
47 	void *startup_addr;
48 };
49 
50 static struct omap_smp_config cfg;
51 
52 static const struct omap_smp_config omap443x_cfg __initconst = {
53 	.cpu1_rstctrl_pa = 0x4824380c,
54 	.startup_addr = omap4_secondary_startup,
55 };
56 
57 static const struct omap_smp_config omap446x_cfg __initconst = {
58 	.cpu1_rstctrl_pa = 0x4824380c,
59 	.startup_addr = omap4460_secondary_startup,
60 };
61 
62 static const struct omap_smp_config omap5_cfg __initconst = {
63 	.cpu1_rstctrl_pa = 0x48243810,
64 	.startup_addr = omap5_secondary_startup,
65 };
66 
67 static DEFINE_SPINLOCK(boot_lock);
68 
69 void __iomem *omap4_get_scu_base(void)
70 {
71 	return cfg.scu_base;
72 }
73 
74 #ifdef CONFIG_OMAP5_ERRATA_801819
75 void omap5_erratum_workaround_801819(void)
76 {
77 	u32 acr, revidr;
78 	u32 acr_mask;
79 
80 	/* REVIDR[3] indicates erratum fix available on silicon */
81 	asm volatile ("mrc p15, 0, %0, c0, c0, 6" : "=r" (revidr));
82 	if (revidr & (0x1 << 3))
83 		return;
84 
85 	asm volatile ("mrc p15, 0, %0, c1, c0, 1" : "=r" (acr));
86 	/*
87 	 * BIT(27) - Disables streaming. All write-allocate lines allocate in
88 	 * the L1 or L2 cache.
89 	 * BIT(25) - Disables streaming. All write-allocate lines allocate in
90 	 * the L1 cache.
91 	 */
92 	acr_mask = (0x3 << 25) | (0x3 << 27);
93 	/* do we already have it done.. if yes, skip expensive smc */
94 	if ((acr & acr_mask) == acr_mask)
95 		return;
96 
97 	acr |= acr_mask;
98 	omap_smc1(OMAP5_DRA7_MON_SET_ACR_INDEX, acr);
99 
100 	pr_debug("%s: ARM erratum workaround 801819 applied on CPU%d\n",
101 		 __func__, smp_processor_id());
102 }
103 #else
104 static inline void omap5_erratum_workaround_801819(void) { }
105 #endif
106 
107 static void omap4_secondary_init(unsigned int cpu)
108 {
109 	/*
110 	 * Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
111 	 * OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
112 	 * init and for CPU1, a secure PPA API provided. CPU0 must be ON
113 	 * while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
114 	 * OMAP443X GP devices- SMP bit isn't accessible.
115 	 * OMAP446X GP devices - SMP bit access is enabled on both CPUs.
116 	 */
117 	if (soc_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
118 		omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
119 							4, 0, 0, 0, 0, 0);
120 
121 	if (soc_is_omap54xx() || soc_is_dra7xx()) {
122 		/*
123 		 * Configure the CNTFRQ register for the secondary cpu's which
124 		 * indicates the frequency of the cpu local timers.
125 		 */
126 		set_cntfreq();
127 		/* Configure ACR to disable streaming WA for 801819 */
128 		omap5_erratum_workaround_801819();
129 	}
130 
131 	/*
132 	 * Synchronise with the boot thread.
133 	 */
134 	spin_lock(&boot_lock);
135 	spin_unlock(&boot_lock);
136 }
137 
138 static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
139 {
140 	static struct clockdomain *cpu1_clkdm;
141 	static bool booted;
142 	static struct powerdomain *cpu1_pwrdm;
143 	void __iomem *base = omap_get_wakeupgen_base();
144 
145 	/*
146 	 * Set synchronisation state between this boot processor
147 	 * and the secondary one
148 	 */
149 	spin_lock(&boot_lock);
150 
151 	/*
152 	 * Update the AuxCoreBoot0 with boot state for secondary core.
153 	 * omap4_secondary_startup() routine will hold the secondary core till
154 	 * the AuxCoreBoot1 register is updated with cpu state
155 	 * A barrier is added to ensure that write buffer is drained
156 	 */
157 	if (omap_secure_apis_support())
158 		omap_modify_auxcoreboot0(0x200, 0xfffffdff);
159 	else
160 		writel_relaxed(0x20, base + OMAP_AUX_CORE_BOOT_0);
161 
162 	if (!cpu1_clkdm && !cpu1_pwrdm) {
163 		cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
164 		cpu1_pwrdm = pwrdm_lookup("cpu1_pwrdm");
165 	}
166 
167 	/*
168 	 * The SGI(Software Generated Interrupts) are not wakeup capable
169 	 * from low power states. This is known limitation on OMAP4 and
170 	 * needs to be worked around by using software forced clockdomain
171 	 * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
172 	 * software force wakeup. The clockdomain is then put back to
173 	 * hardware supervised mode.
174 	 * More details can be found in OMAP4430 TRM - Version J
175 	 * Section :
176 	 *	4.3.4.2 Power States of CPU0 and CPU1
177 	 */
178 	if (booted && cpu1_pwrdm && cpu1_clkdm) {
179 		/*
180 		 * GIC distributor control register has changed between
181 		 * CortexA9 r1pX and r2pX. The Control Register secure
182 		 * banked version is now composed of 2 bits:
183 		 * bit 0 == Secure Enable
184 		 * bit 1 == Non-Secure Enable
185 		 * The Non-Secure banked register has not changed
186 		 * Because the ROM Code is based on the r1pX GIC, the CPU1
187 		 * GIC restoration will cause a problem to CPU0 Non-Secure SW.
188 		 * The workaround must be:
189 		 * 1) Before doing the CPU1 wakeup, CPU0 must disable
190 		 * the GIC distributor
191 		 * 2) CPU1 must re-enable the GIC distributor on
192 		 * it's wakeup path.
193 		 */
194 		if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
195 			local_irq_disable();
196 			gic_dist_disable();
197 		}
198 
199 		/*
200 		 * Ensure that CPU power state is set to ON to avoid CPU
201 		 * powerdomain transition on wfi
202 		 */
203 		clkdm_deny_idle_nolock(cpu1_clkdm);
204 		pwrdm_set_next_pwrst(cpu1_pwrdm, PWRDM_POWER_ON);
205 		clkdm_allow_idle_nolock(cpu1_clkdm);
206 
207 		if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
208 			while (gic_dist_disabled()) {
209 				udelay(1);
210 				cpu_relax();
211 			}
212 			gic_timer_retrigger();
213 			local_irq_enable();
214 		}
215 	} else {
216 		dsb_sev();
217 		booted = true;
218 	}
219 
220 	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
221 
222 	/*
223 	 * Now the secondary core is starting up let it run its
224 	 * calibrations, then wait for it to finish
225 	 */
226 	spin_unlock(&boot_lock);
227 
228 	return 0;
229 }
230 
231 /*
232  * Initialise the CPU possible map early - this describes the CPUs
233  * which may be present or become present in the system.
234  */
235 static void __init omap4_smp_init_cpus(void)
236 {
237 	unsigned int i = 0, ncores = 1, cpu_id;
238 
239 	/* Use ARM cpuid check here, as SoC detection will not work so early */
240 	cpu_id = read_cpuid_id() & CPU_MASK;
241 	if (cpu_id == CPU_CORTEX_A9) {
242 		/*
243 		 * Currently we can't call ioremap here because
244 		 * SoC detection won't work until after init_early.
245 		 */
246 		cfg.scu_base =  OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
247 		BUG_ON(!cfg.scu_base);
248 		ncores = scu_get_core_count(cfg.scu_base);
249 	} else if (cpu_id == CPU_CORTEX_A15) {
250 		ncores = OMAP5_CORE_COUNT;
251 	}
252 
253 	/* sanity check */
254 	if (ncores > nr_cpu_ids) {
255 		pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
256 			ncores, nr_cpu_ids);
257 		ncores = nr_cpu_ids;
258 	}
259 
260 	for (i = 0; i < ncores; i++)
261 		set_cpu_possible(i, true);
262 }
263 
264 static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
265 {
266 	void __iomem *base = omap_get_wakeupgen_base();
267 	const struct omap_smp_config *c = NULL;
268 
269 	if (soc_is_omap443x())
270 		c = &omap443x_cfg;
271 	else if (soc_is_omap446x())
272 		c = &omap446x_cfg;
273 	else if (soc_is_dra74x() || soc_is_omap54xx())
274 		c = &omap5_cfg;
275 
276 	if (!c) {
277 		pr_err("%s Unknown SMP SoC?\n", __func__);
278 		return;
279 	}
280 
281 	/* Must preserve cfg.scu_base set earlier */
282 	cfg.cpu1_rstctrl_pa = c->cpu1_rstctrl_pa;
283 	cfg.startup_addr = c->startup_addr;
284 
285 	if (soc_is_dra74x() || soc_is_omap54xx()) {
286 		if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE)
287 			cfg.startup_addr = omap5_secondary_hyp_startup;
288 		omap5_erratum_workaround_801819();
289 	}
290 
291 	cfg.cpu1_rstctrl_va = ioremap(cfg.cpu1_rstctrl_pa, 4);
292 	if (!cfg.cpu1_rstctrl_va)
293 		return;
294 
295 	/*
296 	 * Initialise the SCU and wake up the secondary core using
297 	 * wakeup_secondary().
298 	 */
299 	if (cfg.scu_base)
300 		scu_enable(cfg.scu_base);
301 
302 	/*
303 	 * Reset CPU1 before configuring, otherwise kexec will
304 	 * end up trying to use old kernel startup address.
305 	 */
306 	if (cfg.cpu1_rstctrl_va) {
307 		writel_relaxed(1, cfg.cpu1_rstctrl_va);
308 		readl_relaxed(cfg.cpu1_rstctrl_va);
309 		writel_relaxed(0, cfg.cpu1_rstctrl_va);
310 	}
311 
312 	/*
313 	 * Write the address of secondary startup routine into the
314 	 * AuxCoreBoot1 where ROM code will jump and start executing
315 	 * on secondary core once out of WFE
316 	 * A barrier is added to ensure that write buffer is drained
317 	 */
318 	if (omap_secure_apis_support())
319 		omap_auxcoreboot_addr(__pa_symbol(cfg.startup_addr));
320 	else
321 		writel_relaxed(__pa_symbol(cfg.startup_addr),
322 			       base + OMAP_AUX_CORE_BOOT_1);
323 }
324 
325 const struct smp_operations omap4_smp_ops __initconst = {
326 	.smp_init_cpus		= omap4_smp_init_cpus,
327 	.smp_prepare_cpus	= omap4_smp_prepare_cpus,
328 	.smp_secondary_init	= omap4_secondary_init,
329 	.smp_boot_secondary	= omap4_boot_secondary,
330 #ifdef CONFIG_HOTPLUG_CPU
331 	.cpu_die		= omap4_cpu_die,
332 	.cpu_kill		= omap4_cpu_kill,
333 #endif
334 };
335