blob: beab2054e62552b10c61c7649b581ca424a509c8 [file] [log] [blame]
/* Copyright (c) 2012, Code Aurora Forum. 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 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#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 <linux/interrupt.h>
#include <asm/cacheflush.h>
#include <asm/hardware/gic.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/smp_scu.h>
#include <asm/unified.h>
#include <mach/msm_iomap.h>
#include <mach/smp.h>
#include "pm.h"
#define MSM_CORE1_RESET 0xA8600590
#define MSM_CORE1_STATUS_MSK 0x02800000
/*
* control for which core is the next to come out of the secondary
* boot "holding pen"
*/
int pen_release = -1;
static bool cold_boot_done;
static uint32_t *msm8625_boot_vector;
/*
* Write pen_release in a way that is guaranteed to be visible to all
* observers, irrespective of whether they're taking part in coherency
* or not. This is necessary for the hotplug code to work reliably.
*/
static void __cpuinit write_pen_release(int val)
{
pen_release = val;
smp_wmb();
__cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
}
static void __iomem *scu_base_addr(void)
{
return MSM_SCU_BASE;
}
static DEFINE_SPINLOCK(boot_lock);
/*
* MP_CORE_IPC will be used to generate interrupt and can be used by either
* of core.
* To bring core1 out of GDFS we need to raise the SPI using the MP_CORE_IPC.
*/
static void raise_clear_spi(unsigned int cpu, bool set)
{
int value;
value = __raw_readl(MSM_CSR_BASE + 0x54);
if (set)
__raw_writel(value | BIT(cpu), MSM_CSR_BASE + 0x54);
else
__raw_writel(value & ~BIT(cpu), MSM_CSR_BASE + 0x54);
mb();
}
static void clear_pending_spi(unsigned int irq)
{
/* Clear the IRQ from the ENABLE_SET */
local_irq_disable();
gic_clear_spi_pending(irq);
local_irq_enable();
}
void __cpuinit platform_secondary_init(unsigned int cpu)
{
pr_debug("CPU%u: Booted secondary processor\n", cpu);
WARN_ON(msm_platform_secondary_init(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);
/*
* let the primary processor know we're out of the
* pen, then head off into the C entry point
*/
write_pen_release(-1);
/* clear the IPC1(SPI-8) pending SPI */
if (power_collapsed) {
raise_clear_spi(1, false);
clear_pending_spi(MSM8625_INT_ACSR_MP_CORE_IPC1);
power_collapsed = 0;
}
/*
* Synchronise with the boot thread.
*/
spin_lock(&boot_lock);
spin_unlock(&boot_lock);
}
static int __cpuinit msm8625_release_secondary(void)
{
void __iomem *base_ptr;
int value = 0;
unsigned long timeout;
/*
* loop to ensure that the GHS_STATUS_CORE1 bit in the
* MPA5_STATUS_REG(0x3c) is set. The timeout for the while
* loop can be set as 20us as of now
*/
timeout = jiffies + usecs_to_jiffies(20);
while (time_before(jiffies, timeout)) {
value = __raw_readl(MSM_CFG_CTL_BASE + 0x3c);
if ((value & MSM_CORE1_STATUS_MSK) ==
MSM_CORE1_STATUS_MSK)
break;
udelay(1);
}
if (!value) {
pr_err("Core 1 cannot be brought out of Reset!!!\n");
return -ENODEV;
}
base_ptr = ioremap_nocache(MSM_CORE1_RESET, SZ_4);
if (!base_ptr)
return -ENODEV;
/* Reset core 1 out of reset */
__raw_writel(0x0, base_ptr);
mb();
iounmap(base_ptr);
return 0;
}
int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
{
unsigned long timeout;
if (cold_boot_done == false) {
if (msm8625_release_secondary()) {
pr_err("Failed to release secondary core\n");
return -ENODEV;
}
cold_boot_done = true;
}
/*
* Set synchronisation state between this boot processor
* and the secondary one
*/
spin_lock(&boot_lock);
/*
* This is really belt and braces; we hold unintended secondary
* CPUs in the holding pen until we're ready for them. However,
* since we haven't sent them a soft interrupt, they shouldn't
* be there.
*/
write_pen_release(cpu);
/*
* Send the secondary CPU a soft interrupt, thereby causing
* the boot monitor to read the system wide flags register,
* and branch to the address found there.
*
* power_collapsed is the flag which will be updated for Powercollapse.
* Once we are out of PC, as Core1 will be in the state of GDFS which
* needs to be brought out by raising an SPI.
*/
if (power_collapsed) {
core1_gic_configure_and_raise();
raise_clear_spi(1, true);
} else {
gic_raise_softirq(cpumask_of(cpu), 1);
}
timeout = jiffies + (1 * HZ);
while (time_before(jiffies, timeout)) {
smp_rmb();
if (pen_release == -1)
break;
udelay(10);
}
/*
* 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)
{
void __iomem *scu_base = scu_base_addr();
unsigned int i, ncores;
ncores = scu_base ? scu_get_core_count(scu_base) : 1;
for (i = 0; i < ncores; i++)
set_cpu_possible(i, true);
set_smp_cross_call(gic_raise_softirq);
}
static void __init msm8625_boot_vector_init(uint32_t *boot_vector,
unsigned long entry)
{
if (!boot_vector)
return;
msm8625_boot_vector = boot_vector;
msm8625_boot_vector[0] = 0xE51FF004; /* ldr pc, 4 */
msm8625_boot_vector[1] = entry;
}
void __init platform_smp_prepare_cpus(unsigned int max_cpus)
{
int i, value;
void __iomem *second_ptr;
/*
* 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);
scu_enable(scu_base_addr());
/*
* Write the address of secondary startup into the
* boot remapper register. The secondary CPU branches to this address.
*/
__raw_writel(MSM8625_SECONDARY_PHYS, (MSM_CFG_CTL_BASE + 0x34));
mb();
second_ptr = ioremap_nocache(MSM8625_SECONDARY_PHYS, SZ_8);
if (!second_ptr) {
pr_err("failed to ioremap for secondary core\n");
return;
}
msm8625_boot_vector_init(second_ptr,
virt_to_phys(msm_secondary_startup));
iounmap(second_ptr);
/* Enable boot remapper address: bit 26 for core1 */
value = __raw_readl(MSM_CFG_CTL_BASE + 0x30);
__raw_writel(value | (0x4 << 24), MSM_CFG_CTL_BASE + 0x30) ;
mb();
}