linux/arch/arm/mach-tegra/platsmp.c

134 lines
3.1 KiB
C
Raw Normal View History

/*
* 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 <asm/hardware/gic.h>
#include <asm/mach-types.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)
{
/*
* 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_secondary_init(0);
/*
* 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);
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);
set_smp_cross_call(gic_raise_softirq);
}
void __init platform_smp_prepare_cpus(unsigned int max_cpus)
{
scu_enable(scu_base);
}