2 * OMAP4 SMP source file. It contains platform specific fucntions
3 * needed for the linux smp kernel.
5 * Copyright (C) 2009 Texas Instruments, Inc.
8 * Santosh Shilimkar <santosh.shilimkar@ti.com>
10 * Platform file needed for the OMAP4 SMP. This file is based on arm
11 * realview smp platform.
12 * * Copyright (c) 2002 ARM Limited.
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.
18 #include <linux/init.h>
19 #include <linux/device.h>
20 #include <linux/smp.h>
22 #include <linux/irqchip/arm-gic.h>
24 #include <asm/smp_scu.h>
26 #include "omap-secure.h"
27 #include "omap-wakeupgen.h"
28 #include <asm/cputype.h>
33 #include "clockdomain.h"
36 #define CPU_MASK 0xff0ffff0
37 #define CPU_CORTEX_A9 0x410FC090
38 #define CPU_CORTEX_A15 0x410FC0F0
40 #define OMAP5_CORE_COUNT 0x2
44 /* SCU base address */
45 static void __iomem *scu_base;
47 static DEFINE_SPINLOCK(boot_lock);
49 void __iomem *omap4_get_scu_base(void)
54 static void __cpuinit omap4_secondary_init(unsigned int cpu)
57 * Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
58 * OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
59 * init and for CPU1, a secure PPA API provided. CPU0 must be ON
60 * while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
61 * OMAP443X GP devices- SMP bit isn't accessible.
62 * OMAP446X GP devices - SMP bit access is enabled on both CPUs.
64 if (cpu_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
65 omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
69 * Synchronise with the boot thread.
71 spin_lock(&boot_lock);
72 spin_unlock(&boot_lock);
75 static int __cpuinit omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
77 static struct clockdomain *cpu1_clkdm;
79 void __iomem *base = omap_get_wakeupgen_base();
82 * Set synchronisation state between this boot processor
83 * and the secondary one
85 spin_lock(&boot_lock);
88 * Update the AuxCoreBoot0 with boot state for secondary core.
89 * omap_secondary_startup() routine will hold the secondary core till
90 * the AuxCoreBoot1 register is updated with cpu state
91 * A barrier is added to ensure that write buffer is drained
93 if (omap_secure_apis_support())
94 omap_modify_auxcoreboot0(0x200, 0xfffffdff);
96 __raw_writel(0x20, base + OMAP_AUX_CORE_BOOT_0);
99 cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
102 * The SGI(Software Generated Interrupts) are not wakeup capable
103 * from low power states. This is known limitation on OMAP4 and
104 * needs to be worked around by using software forced clockdomain
105 * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
106 * software force wakeup. The clockdomain is then put back to
107 * hardware supervised mode.
108 * More details can be found in OMAP4430 TRM - Version J
110 * 4.3.4.2 Power States of CPU0 and CPU1
114 * GIC distributor control register has changed between
115 * CortexA9 r1pX and r2pX. The Control Register secure
116 * banked version is now composed of 2 bits:
117 * bit 0 == Secure Enable
118 * bit 1 == Non-Secure Enable
119 * The Non-Secure banked register has not changed
120 * Because the ROM Code is based on the r1pX GIC, the CPU1
121 * GIC restoration will cause a problem to CPU0 Non-Secure SW.
122 * The workaround must be:
123 * 1) Before doing the CPU1 wakeup, CPU0 must disable
124 * the GIC distributor
125 * 2) CPU1 must re-enable the GIC distributor on
128 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
133 clkdm_wakeup(cpu1_clkdm);
134 clkdm_allow_idle(cpu1_clkdm);
136 if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
137 while (gic_dist_disabled()) {
141 gic_timer_retrigger();
149 arch_send_wakeup_ipi_mask(cpumask_of(cpu));
152 * Now the secondary core is starting up let it run its
153 * calibrations, then wait for it to finish
155 spin_unlock(&boot_lock);
161 * Initialise the CPU possible map early - this describes the CPUs
162 * which may be present or become present in the system.
164 static void __init omap4_smp_init_cpus(void)
166 unsigned int i = 0, ncores = 1, cpu_id;
168 /* Use ARM cpuid check here, as SoC detection will not work so early */
169 cpu_id = read_cpuid(CPUID_ID) & CPU_MASK;
170 if (cpu_id == CPU_CORTEX_A9) {
172 * Currently we can't call ioremap here because
173 * SoC detection won't work until after init_early.
175 scu_base = OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
177 ncores = scu_get_core_count(scu_base);
178 } else if (cpu_id == CPU_CORTEX_A15) {
179 ncores = OMAP5_CORE_COUNT;
183 if (ncores > nr_cpu_ids) {
184 pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
189 for (i = 0; i < ncores; i++)
190 set_cpu_possible(i, true);
193 static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
195 void *startup_addr = omap_secondary_startup;
196 void __iomem *base = omap_get_wakeupgen_base();
199 * Initialise the SCU and wake up the secondary core using
200 * wakeup_secondary().
203 scu_enable(scu_base);
205 if (cpu_is_omap446x()) {
206 startup_addr = omap_secondary_startup_4460;
207 pm44xx_errata |= PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD;
211 * Write the address of secondary startup routine into the
212 * AuxCoreBoot1 where ROM code will jump and start executing
213 * on secondary core once out of WFE
214 * A barrier is added to ensure that write buffer is drained
216 if (omap_secure_apis_support())
217 omap_auxcoreboot_addr(virt_to_phys(startup_addr));
219 __raw_writel(virt_to_phys(omap5_secondary_startup),
220 base + OMAP_AUX_CORE_BOOT_1);
224 struct smp_operations omap4_smp_ops __initdata = {
225 .smp_init_cpus = omap4_smp_init_cpus,
226 .smp_prepare_cpus = omap4_smp_prepare_cpus,
227 .smp_secondary_init = omap4_secondary_init,
228 .smp_boot_secondary = omap4_boot_secondary,
229 #ifdef CONFIG_HOTPLUG_CPU
230 .cpu_die = omap4_cpu_die,