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ARM: shmobile: Update r8a7779 to check SCU for hotplug

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Update the r8a7779 CPU Hotplug code to use SCU PSR
to wait for the target CPU core. Previously the
shared code in hotplug.c was used to let cpu_kill()
wait for cpu_die(). With this change in place the
r8a7779 SMP code does not depend on hotplug.c anymore.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
This commit is contained in:
Magnus Damm 2013-02-18 22:47:25 +09:00 committed by Simon Horman
parent abf88136f7
commit bbf2627c77
1 changed files with 32 additions and 6 deletions
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38
arch/arm/mach-shmobile/smp-r8a7779.c
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@ -26,6 +26,7 @@
#include <linux/irqchip/arm-gic.h>
#include <mach/common.h>
#include <mach/r8a7779.h>
#include <asm/cacheflush.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include <asm/smp_twd.h>
@ -68,6 +69,16 @@ void __init r8a7779_register_twd(void)
}
#endif
static int r8a7779_scu_psr_core_disabled(int cpu)
{
unsigned long mask = 3 << (cpu * 8);
if ((__raw_readl(shmobile_scu_base + 8) & mask) == mask)
return 1;
return 0;
}
static void modify_scu_cpu_psr(unsigned long set, unsigned long clr)
{
void __iomem *scu_base = shmobile_scu_base;
@ -89,9 +100,6 @@ static int r8a7779_platform_cpu_kill(unsigned int cpu)
cpu = cpu_logical_map(cpu);
/* disable cache coherency */
modify_scu_cpu_psr(3 << (cpu * 8), 0);
if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
ch = r8a7779_ch_cpu[cpu];
@ -110,7 +118,7 @@ static int __maybe_unused r8a7779_cpu_kill(unsigned int cpu)
* finish before asking SoC-specific code to power off the CPU core.
*/
for (k = 0; k < 1000; k++) {
if (shmobile_cpu_is_dead(cpu))
if (r8a7779_scu_psr_core_disabled(cpu))
return r8a7779_platform_cpu_kill(cpu);
mdelay(1);
@ -119,6 +127,24 @@ static int __maybe_unused r8a7779_cpu_kill(unsigned int cpu)
return 0;
}
static void __maybe_unused r8a7779_cpu_die(unsigned int cpu)
{
dsb();
flush_cache_all();
/* disable cache coherency */
modify_scu_cpu_psr(3 << (cpu * 8), 0);
/* Endless loop until power off from r8a7779_cpu_kill() */
while (1)
cpu_do_idle();
}
static int __maybe_unused r8a7779_cpu_disable(unsigned int cpu)
{
/* only CPU1->3 have power domains, do not allow hotplug of CPU0 */
return cpu == 0 ? -EPERM : 0;
}
static void __cpuinit r8a7779_secondary_init(unsigned int cpu)
{
@ -179,7 +205,7 @@ struct smp_operations r8a7779_smp_ops __initdata = {
.smp_boot_secondary = r8a7779_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_kill = r8a7779_cpu_kill,
.cpu_die = shmobile_cpu_die,
.cpu_disable = shmobile_cpu_disable,
.cpu_die = r8a7779_cpu_die,
.cpu_disable = r8a7779_cpu_disable,
#endif
};