@@ -45,6 +45,20 @@
#define CCI_SNOOP 0x0000
#define CCI_STATUS 0x000c
+static inline void r8a73a4_execute_wfe_as_nop(void)
+{
+ unsigned int v;
+
+ /* set bit 7 in ACTLR */
+ asm volatile(
+ " mrc p15, 0, %0, c1, c0, 1\n"
+ " orr %0, %0, #0x40\n"
+ " mcr p15, 0, %0, c1, c0, 1\n"
+ : "=&r" (v)
+ :
+ : "cc");
+}
+
static void __init r8a73a4_smp_prepare_cpus(unsigned int max_cpus)
{
u32 bar;
@@ -71,6 +85,8 @@ static void __init r8a73a4_smp_prepare_c
while (__raw_readl(p + CCI_STATUS))
/* wait for pending bit low */;
iounmap(p);
+
+ r8a73a4_execute_wfe_as_nop();
}
static int __cpuinit r8a73a4_boot_secondary(unsigned int cpu, struct task_struct *idle)
@@ -85,6 +101,13 @@ static int __cpuinit r8a73a4_boot_second
return 0;
}
+static void __cpuinit r8a73a4_secondary_init(unsigned int cpu)
+{
+ /* CA15 need SW workaround */
+ if (cpu_logical_map(cpu) < 4)
+ r8a73a4_execute_wfe_as_nop();
+}
+
#ifdef CONFIG_HOTPLUG_CPU
static int r8a73a4_cpu_kill(unsigned int cpu)
{
@@ -169,6 +192,7 @@ static int r8a73a4_cpu_disable(unsigned
struct smp_operations r8a73a4_smp_ops __initdata = {
.smp_prepare_cpus = r8a73a4_smp_prepare_cpus,
.smp_boot_secondary = r8a73a4_boot_secondary,
+ .smp_secondary_init = r8a73a4_secondary_init,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_kill = r8a73a4_cpu_kill,
.cpu_die = r8a73a4_cpu_die,
From: Magnus Damm <damm@opensource.se> Configure CA15 included in r8a73a4 to treat WFE as NOP. This works around hardware issue found in APE6, needed for CA7 cluster to work together with CA15 cluster. Not-yet-Signed-off-by: Magnus Damm <damm@opensource.se> --- arch/arm/mach-shmobile/smp-r8a73a4.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html