/*
* OMAP4 SMP source file. It contains platform specific fucntions
* 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/cacheflush.h>
#include <asm/smp_scu.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
u16 pm44xx_errata;
/* SCU base address */
static void __iomem *scu_base;
static DEFINE_SPINLOCK(boot_lock);
void __iomem *omap4_get_scu_base(void)
{
return scu_base;
}
static void __cpuinit 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);
/*
* 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);
}
static int __cpuinit omap4_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
static struct clockdomain *cpu1_clkdm;
static bool booted;
void __iomem *base = omap_get_wakeupgen_base();
/*
* Set synchronisation state between this boot processor
* and the secondary one
*/
spin_lock(&boot_lock);
/*
* Update the AuxCoreBoot0 with boot state for secondary core.
* omap_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
__raw_writel(0x20, base + OMAP_AUX_CORE_BOOT_0);
flush_cache_all();
smp_wmb();
if (!cpu1_clkdm)
cpu1_clkdm = clkdm_lookup("mpu1_clkdm");
/*
* 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) {
/*
* 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();
}
clkdm_wakeup(cpu1_clkdm);
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
*/
spin_unlock(&boot_lock);
return 0;
}
static void __init wakeup_secondary(void)
{
void *startup_addr = omap_secondary_startup;
void __iomem *base = omap_get_wakeupgen_base();
if (cpu_is_omap446x()) {
startup_addr = omap_secondary_startup_4460;
pm44xx_errata |= PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD;
}
/*
* 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
__raw_writel(virt_to_phys(omap5_secondary_startup),
base + OMAP_AUX_CORE_BOOT_1);
smp_wmb();
/*
* Send a 'sev' to wake the secondary core from WFE.
* Drain the outstanding writes to memory
*/
dsb_sev();
mb();
}
/*
* 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(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)
{
/*
* Initialise the SCU and wake up the secondary core using
* wakeup_secondary().
*/
if (scu_base)
scu_enable(scu_base);
wakeup_secondary();
}
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
};
