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authorColin Cross <ccross@android.com>2010-02-22 04:46:23 +0300
committerErik Gilling <konkers@android.com>2010-08-06 01:57:01 +0400
commit1cea7326b3fff97d17d33fb8f33163409a84431b (patch)
tree6f8964633b9ca49a7a86921007d0e8a24654e5ad /arch/arm/mach-tegra/platsmp.c
parentd861196163e30c07add471562b45dce38517c9b2 (diff)
downloadlinux-1cea7326b3fff97d17d33fb8f33163409a84431b.tar.xz
[ARM] tegra: SMP support
Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Erik Gilling <konkers@android.com>
Diffstat (limited to 'arch/arm/mach-tegra/platsmp.c')
-rw-r--r--arch/arm/mach-tegra/platsmp.c156
1 files changed, 156 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c
new file mode 100644
index 000000000000..1c0fd92cab39
--- /dev/null
+++ b/arch/arm/mach-tegra/platsmp.c
@@ -0,0 +1,156 @@
+/*
+ * linux/arch/arm/mach-tegra/platsmp.c
+ *
+ * Copyright (C) 2002 ARM Ltd.
+ * All Rights Reserved
+ *
+ * Copyright (C) 2009 Palm
+ * All Rights Reserved
+ *
+ * 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/errno.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <mach/hardware.h>
+#include <asm/mach-types.h>
+#include <asm/localtimer.h>
+#include <asm/smp_scu.h>
+
+#include <mach/iomap.h>
+
+extern void tegra_secondary_startup(void);
+
+static DEFINE_SPINLOCK(boot_lock);
+static void __iomem *scu_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE);
+
+#define EVP_CPU_RESET_VECTOR \
+ (IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE) + 0x100)
+#define CLK_RST_CONTROLLER_CLK_CPU_CMPLX \
+ (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x4c)
+#define CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR \
+ (IO_ADDRESS(TEGRA_CLK_RESET_BASE) + 0x344)
+
+void __cpuinit platform_secondary_init(unsigned int cpu)
+{
+ trace_hardirqs_off();
+
+ /*
+ * if any interrupts are already enabled for the primary
+ * core (e.g. timer irq), then they will not have been enabled
+ * for us: do so
+ */
+ gic_cpu_init(0, IO_ADDRESS(TEGRA_ARM_PERIF_BASE) + 0x100);
+
+ /*
+ * Synchronise with the boot thread.
+ */
+ spin_lock(&boot_lock);
+ spin_unlock(&boot_lock);
+}
+
+int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ unsigned long old_boot_vector;
+ unsigned long boot_vector;
+ unsigned long timeout;
+ u32 reg;
+
+ /*
+ * set synchronisation state between this boot processor
+ * and the secondary one
+ */
+ spin_lock(&boot_lock);
+
+
+ /* set the reset vector to point to the secondary_startup routine */
+
+ boot_vector = virt_to_phys(tegra_secondary_startup);
+ old_boot_vector = readl(EVP_CPU_RESET_VECTOR);
+ writel(boot_vector, EVP_CPU_RESET_VECTOR);
+
+ /* enable cpu clock on cpu1 */
+ reg = readl(CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
+ writel(reg & ~(1<<9), CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
+
+ reg = (1<<13) | (1<<9) | (1<<5) | (1<<1);
+ writel(reg, CLK_RST_CONTROLLER_RST_CPU_CMPLX_CLR);
+
+ smp_wmb();
+ flush_cache_all();
+
+ /* unhalt the cpu */
+ writel(0, IO_ADDRESS(TEGRA_FLOW_CTRL_BASE) + 0x14);
+
+ timeout = jiffies + (1 * HZ);
+ while (time_before(jiffies, timeout)) {
+ if (readl(EVP_CPU_RESET_VECTOR) != boot_vector)
+ break;
+ udelay(10);
+ }
+
+ /* put the old boot vector back */
+ writel(old_boot_vector, EVP_CPU_RESET_VECTOR);
+
+ /*
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+ 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.
+ */
+void __init smp_init_cpus(void)
+{
+ unsigned int i, ncores = scu_get_core_count(scu_base);
+
+ for (i = 0; i < ncores; i++)
+ cpu_set(i, cpu_possible_map);
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ unsigned int ncores = scu_get_core_count(scu_base);
+ unsigned int cpu = smp_processor_id();
+ int i;
+
+ smp_store_cpu_info(cpu);
+
+ /*
+ * are we trying to boot more cores than exist?
+ */
+ if (max_cpus > ncores)
+ max_cpus = ncores;
+
+ /*
+ * Initialise the present map, which describes the set of CPUs
+ * actually populated at the present time.
+ */
+ for (i = 0; i < max_cpus; i++)
+ set_cpu_present(i, true);
+
+ /*
+ * Initialise the SCU if there are more than one CPU and let
+ * them know where to start. Note that, on modern versions of
+ * MILO, the "poke" doesn't actually do anything until each
+ * individual core is sent a soft interrupt to get it out of
+ * WFI
+ */
+ if (max_cpus > 1) {
+ percpu_timer_setup();
+ scu_enable(scu_base);
+ }
+}