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-rw-r--r--kernel/arch/arm/mach-omap2/omap-smp.c252
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diff --git a/kernel/arch/arm/mach-omap2/omap-smp.c b/kernel/arch/arm/mach-omap2/omap-smp.c
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+++ b/kernel/arch/arm/mach-omap2/omap-smp.c
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+/*
+ * OMAP4 SMP source file. It contains platform specific functions
+ * needed for the linux smp kernel.
+ *
+ * Copyright (C) 2009 Texas Instruments, Inc.
+ *
+ * Author:
+ * Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * Platform file needed for the OMAP4 SMP. This file is based on arm
+ * realview smp platform.
+ * * Copyright (c) 2002 ARM Limited.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+#include <linux/irqchip/arm-gic.h>
+
+#include <asm/smp_scu.h>
+#include <asm/virt.h>
+
+#include "omap-secure.h"
+#include "omap-wakeupgen.h"
+#include <asm/cputype.h>
+
+#include "soc.h"
+#include "iomap.h"
+#include "common.h"
+#include "clockdomain.h"
+#include "pm.h"
+
+#define CPU_MASK 0xff0ffff0
+#define CPU_CORTEX_A9 0x410FC090
+#define CPU_CORTEX_A15 0x410FC0F0
+
+#define OMAP5_CORE_COUNT 0x2
+
+/* SCU base address */
+static void __iomem *scu_base;
+
+static DEFINE_RAW_SPINLOCK(boot_lock);
+
+void __iomem *omap4_get_scu_base(void)
+{
+ return scu_base;
+}
+
+static void omap4_secondary_init(unsigned int cpu)
+{
+ /*
+ * Configure ACTRL and enable NS SMP bit access on CPU1 on HS device.
+ * OMAP44XX EMU/HS devices - CPU0 SMP bit access is enabled in PPA
+ * init and for CPU1, a secure PPA API provided. CPU0 must be ON
+ * while executing NS_SMP API on CPU1 and PPA version must be 1.4.0+.
+ * OMAP443X GP devices- SMP bit isn't accessible.
+ * OMAP446X GP devices - SMP bit access is enabled on both CPUs.
+ */
+ if (cpu_is_omap443x() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
+ omap_secure_dispatcher(OMAP4_PPA_CPU_ACTRL_SMP_INDEX,
+ 4, 0, 0, 0, 0, 0);
+
+ /*
+ * Configure the CNTFRQ register for the secondary cpu's which
+ * indicates the frequency of the cpu local timers.
+ */
+ if (soc_is_omap54xx() || soc_is_dra7xx())
+ set_cntfreq();
+
+ /*
+ * Synchronise with the boot thread.
+ */
+ raw_spin_lock(&boot_lock);
+ raw_spin_unlock(&boot_lock);
+}
+
+static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ static struct clockdomain *cpu1_clkdm;
+ static bool booted;
+ static struct powerdomain *cpu1_pwrdm;
+ void __iomem *base = omap_get_wakeupgen_base();
+
+ /*
+ * Set synchronisation state between this boot processor
+ * and the secondary one
+ */
+ raw_spin_lock(&boot_lock);
+
+ /*
+ * Update the AuxCoreBoot0 with boot state for secondary core.
+ * omap4_secondary_startup() routine will hold the secondary core till
+ * the AuxCoreBoot1 register is updated with cpu state
+ * A barrier is added to ensure that write buffer is drained
+ */
+ if (omap_secure_apis_support())
+ omap_modify_auxcoreboot0(0x200, 0xfffffdff);
+ else
+ writel_relaxed(0x20, base + OMAP_AUX_CORE_BOOT_0);
+
+ if (!cpu1_clkdm && !cpu1_pwrdm) {
+ cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
+ cpu1_pwrdm = pwrdm_lookup("cpu1_pwrdm");
+ }
+
+ /*
+ * The SGI(Software Generated Interrupts) are not wakeup capable
+ * from low power states. This is known limitation on OMAP4 and
+ * needs to be worked around by using software forced clockdomain
+ * wake-up. To wakeup CPU1, CPU0 forces the CPU1 clockdomain to
+ * software force wakeup. The clockdomain is then put back to
+ * hardware supervised mode.
+ * More details can be found in OMAP4430 TRM - Version J
+ * Section :
+ * 4.3.4.2 Power States of CPU0 and CPU1
+ */
+ if (booted && cpu1_pwrdm && cpu1_clkdm) {
+ /*
+ * GIC distributor control register has changed between
+ * CortexA9 r1pX and r2pX. The Control Register secure
+ * banked version is now composed of 2 bits:
+ * bit 0 == Secure Enable
+ * bit 1 == Non-Secure Enable
+ * The Non-Secure banked register has not changed
+ * Because the ROM Code is based on the r1pX GIC, the CPU1
+ * GIC restoration will cause a problem to CPU0 Non-Secure SW.
+ * The workaround must be:
+ * 1) Before doing the CPU1 wakeup, CPU0 must disable
+ * the GIC distributor
+ * 2) CPU1 must re-enable the GIC distributor on
+ * it's wakeup path.
+ */
+ if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
+ local_irq_disable();
+ gic_dist_disable();
+ }
+
+ /*
+ * Ensure that CPU power state is set to ON to avoid CPU
+ * powerdomain transition on wfi
+ */
+ clkdm_wakeup(cpu1_clkdm);
+ omap_set_pwrdm_state(cpu1_pwrdm, PWRDM_POWER_ON);
+ clkdm_allow_idle(cpu1_clkdm);
+
+ if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD)) {
+ while (gic_dist_disabled()) {
+ udelay(1);
+ cpu_relax();
+ }
+ gic_timer_retrigger();
+ local_irq_enable();
+ }
+ } else {
+ dsb_sev();
+ booted = true;
+ }
+
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+ /*
+ * Now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+ raw_spin_unlock(&boot_lock);
+
+ return 0;
+}
+
+/*
+ * Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ */
+static void __init omap4_smp_init_cpus(void)
+{
+ unsigned int i = 0, ncores = 1, cpu_id;
+
+ /* Use ARM cpuid check here, as SoC detection will not work so early */
+ cpu_id = read_cpuid_id() & CPU_MASK;
+ if (cpu_id == CPU_CORTEX_A9) {
+ /*
+ * Currently we can't call ioremap here because
+ * SoC detection won't work until after init_early.
+ */
+ scu_base = OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
+ BUG_ON(!scu_base);
+ ncores = scu_get_core_count(scu_base);
+ } else if (cpu_id == CPU_CORTEX_A15) {
+ ncores = OMAP5_CORE_COUNT;
+ }
+
+ /* sanity check */
+ if (ncores > nr_cpu_ids) {
+ pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
+ ncores, nr_cpu_ids);
+ ncores = nr_cpu_ids;
+ }
+
+ for (i = 0; i < ncores; i++)
+ set_cpu_possible(i, true);
+}
+
+static void __init omap4_smp_prepare_cpus(unsigned int max_cpus)
+{
+ void *startup_addr = omap4_secondary_startup;
+ void __iomem *base = omap_get_wakeupgen_base();
+
+ /*
+ * Initialise the SCU and wake up the secondary core using
+ * wakeup_secondary().
+ */
+ if (scu_base)
+ scu_enable(scu_base);
+
+ if (cpu_is_omap446x())
+ startup_addr = omap4460_secondary_startup;
+
+ /*
+ * Write the address of secondary startup routine into the
+ * AuxCoreBoot1 where ROM code will jump and start executing
+ * on secondary core once out of WFE
+ * A barrier is added to ensure that write buffer is drained
+ */
+ if (omap_secure_apis_support())
+ omap_auxcoreboot_addr(virt_to_phys(startup_addr));
+ else
+ /*
+ * If the boot CPU is in HYP mode then start secondary
+ * CPU in HYP mode as well.
+ */
+ if ((__boot_cpu_mode & MODE_MASK) == HYP_MODE)
+ writel_relaxed(virt_to_phys(omap5_secondary_hyp_startup),
+ base + OMAP_AUX_CORE_BOOT_1);
+ else
+ writel_relaxed(virt_to_phys(omap5_secondary_startup),
+ base + OMAP_AUX_CORE_BOOT_1);
+
+}
+
+struct smp_operations omap4_smp_ops __initdata = {
+ .smp_init_cpus = omap4_smp_init_cpus,
+ .smp_prepare_cpus = omap4_smp_prepare_cpus,
+ .smp_secondary_init = omap4_secondary_init,
+ .smp_boot_secondary = omap4_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = omap4_cpu_die,
+#endif
+};