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 /* SCU base address */
44 static void __iomem *scu_base;
45
46 static DEFINE_SPINLOCK(boot_lock);
47
omap4_get_scu_base(void)48 void __iomem *omap4_get_scu_base(void)
49 {
50 return scu_base;
51 }
52
omap4_secondary_init(unsigned int cpu)53 static void omap4_secondary_init(unsigned int cpu)
54 {
55 /*
56 * Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
57 * OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
58 * init and for CPU1, a secure PPA API provided. CPU0 must be ON
59 * while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
60 * OMAP443X GP devices- SMP bit isn't accessible.
61 * OMAP446X GP devices - SMP bit access is enabled on both CPUs.
62 */
63 if (cpu_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
64 omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
65 4, 0, 0, 0, 0, 0);
66
67 /*
68 * Configure the CNTFRQ register for the secondary cpu's which
69 * indicates the frequency of the cpu local timers.
70 */
71 if (soc_is_omap54xx() || soc_is_dra7xx())
72 set_cntfreq();
73
74 /*
75 * Synchronise with the boot thread.
76 */
77 spin_lock(&boot_lock);
78 spin_unlock(&boot_lock);
79 }
80
omap4_boot_secondary(unsigned int cpu,struct task_struct * idle)81 static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
82 {
83 static struct clockdomain *cpu1_clkdm;
84 static bool booted;
85 static struct powerdomain *cpu1_pwrdm;
86 void __iomem *base = omap_get_wakeupgen_base();
87
88 /*
89 * Set synchronisation state between this boot processor
90 * and the secondary one
91 */
92 spin_lock(&boot_lock);
93
94 /*
95 * Update the AuxCoreBoot0 with boot state for secondary core.
96 * omap4_secondary_startup() routine will hold the secondary core till
97 * the AuxCoreBoot1 register is updated with cpu state
98 * A barrier is added to ensure that write buffer is drained
99 */
100 if (omap_secure_apis_support())
101 omap_modify_auxcoreboot0(0x200, 0xfffffdff);
102 else
103 writel_relaxed(0x20, base + OMAP_AUX_CORE_BOOT_0);
104
105 if (!cpu1_clkdm && !cpu1_pwrdm) {
106 cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
107 cpu1_pwrdm = pwrdm_lookup("cpu1_pwrdm");
108 }
109
110 /*
111 * The SGI(Software Generated Interrupts) are not wakeup capable
112 * from low power states. This is known limitation on OMAP4 and
113 * needs to be worked around by using software forced clockdomain
114 * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
115 * software force wakeup. The clockdomain is then put back to
116 * hardware supervised mode.
117 * More details can be found in OMAP4430 TRM - Version J
118 * Section :
119 * 4.3.4.2 Power States of CPU0 and CPU1
120 */
121 if (booted && cpu1_pwrdm && cpu1_clkdm) {
122 /*
123 * GIC distributor control register has changed between
124 * CortexA9 r1pX and r2pX. The Control Register secure
125 * banked version is now composed of 2 bits:
126 * bit 0 == Secure Enable
127 * bit 1 == Non-Secure Enable
128 * The Non-Secure banked register has not changed
129 * Because the ROM Code is based on the r1pX GIC, the CPU1
130 * GIC restoration will cause a problem to CPU0 Non-Secure SW.
131 * The workaround must be:
132 * 1) Before doing the CPU1 wakeup, CPU0 must disable
133 * the GIC distributor
134 * 2) CPU1 must re-enable the GIC distributor on
135 * it's wakeup path.
136 */
137 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
138 local_irq_disable();
139 gic_dist_disable();
140 }
141
142 /*
143 * Ensure that CPU power state is set to ON to avoid CPU
144 * powerdomain transition on wfi
145 */
146 clkdm_wakeup_nolock(cpu1_clkdm);
147 pwrdm_set_next_pwrst(cpu1_pwrdm, PWRDM_POWER_ON);
148 clkdm_allow_idle_nolock(cpu1_clkdm);
149
150 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
151 while (gic_dist_disabled()) {
152 udelay(1);
153 cpu_relax();
154 }
155 gic_timer_retrigger();
156 local_irq_enable();
157 }
158 } else {
159 dsb_sev();
160 booted = true;
161 }
162
163 arch_send_wakeup_ipi_mask(cpumask_of(cpu));
164
165 /*
166 * Now the secondary core is starting up let it run its
167 * calibrations, then wait for it to finish
168 */
169 spin_unlock(&boot_lock);
170
171 return 0;
172 }
173
174 /*
175 * Initialise the CPU possible map early - this describes the CPUs
176 * which may be present or become present in the system.
177 */
omap4_smp_init_cpus(void)178 static void __init omap4_smp_init_cpus(void)
179 {
180 unsigned int i = 0, ncores = 1, cpu_id;
181
182 /* Use ARM cpuid check here, as SoC detection will not work so early */
183 cpu_id = read_cpuid_id() & CPU_MASK;
184 if (cpu_id == CPU_CORTEX_A9) {
185 /*
186 * Currently we can't call ioremap here because
187 * SoC detection won't work until after init_early.
188 */
189 scu_base = OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
190 BUG_ON(!scu_base);
191 ncores = scu_get_core_count(scu_base);
192 } else if (cpu_id == CPU_CORTEX_A15) {
193 ncores = OMAP5_CORE_COUNT;
194 }
195
196 /* sanity check */
197 if (ncores > nr_cpu_ids) {
198 pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
199 ncores, nr_cpu_ids);
200 ncores = nr_cpu_ids;
201 }
202
203 for (i = 0; i < ncores; i++)
204 set_cpu_possible(i, true);
205 }
206
omap4_smp_prepare_cpus(unsigned int max_cpus)207 static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
208 {
209 void *startup_addr = omap4_secondary_startup;
210 void __iomem *base = omap_get_wakeupgen_base();
211
212 /*
213 * Initialise the SCU and wake up the secondary core using
214 * wakeup_secondary().
215 */
216 if (scu_base)
217 scu_enable(scu_base);
218
219 if (cpu_is_omap446x())
220 startup_addr = omap4460_secondary_startup;
221
222 /*
223 * Write the address of secondary startup routine into the
224 * AuxCoreBoot1 where ROM code will jump and start executing
225 * on secondary core once out of WFE
226 * A barrier is added to ensure that write buffer is drained
227 */
228 if (omap_secure_apis_support())
229 omap_auxcoreboot_addr(virt_to_phys(startup_addr));
230 else
231 /*
232 * If the boot CPU is in HYP mode then start secondary
233 * CPU in HYP mode as well.
234 */
235 if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE)
236 writel_relaxed(virt_to_phys(omap5_secondary_hyp_startup),
237 base + OMAP_AUX_CORE_BOOT_1);
238 else
239 writel_relaxed(virt_to_phys(omap5_secondary_startup),
240 base + OMAP_AUX_CORE_BOOT_1);
241
242 }
243
244 struct smp_operations omap4_smp_ops __initdata = {
245 .smp_init_cpus = omap4_smp_init_cpus,
246 .smp_prepare_cpus = omap4_smp_prepare_cpus,
247 .smp_secondary_init = omap4_secondary_init,
248 .smp_boot_secondary = omap4_boot_secondary,
249 #ifdef CONFIG_HOTPLUG_CPU
250 .cpu_die = omap4_cpu_die,
251 #endif
252 };
253