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Diffstat (limited to 'arch/powerpc/platforms/85xx/smp.c')
-rw-r--r--arch/powerpc/platforms/85xx/smp.c49
1 files changed, 36 insertions, 13 deletions
diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c
index 6fcfa12..148c2f2 100644
--- a/arch/powerpc/platforms/85xx/smp.c
+++ b/arch/powerpc/platforms/85xx/smp.c
@@ -128,6 +128,19 @@ static void __cpuinit smp_85xx_mach_cpu_die(void)
}
#endif
+static inline void flush_spin_table(void *spin_table)
+{
+ flush_dcache_range((ulong)spin_table,
+ (ulong)spin_table + sizeof(struct epapr_spin_table));
+}
+
+static inline u32 read_spin_table_addr_l(void *spin_table)
+{
+ flush_dcache_range((ulong)spin_table,
+ (ulong)spin_table + sizeof(struct epapr_spin_table));
+ return in_be32(&((struct epapr_spin_table *)spin_table)->addr_l);
+}
+
static int __cpuinit smp_85xx_kick_cpu(int nr)
{
unsigned long flags;
@@ -161,8 +174,8 @@ static int __cpuinit smp_85xx_kick_cpu(int nr)
/* Map the spin table */
if (ioremappable)
- spin_table = ioremap(*cpu_rel_addr,
- sizeof(struct epapr_spin_table));
+ spin_table = ioremap_prot(*cpu_rel_addr,
+ sizeof(struct epapr_spin_table), _PAGE_COHERENT);
else
spin_table = phys_to_virt(*cpu_rel_addr);
@@ -173,7 +186,16 @@ static int __cpuinit smp_85xx_kick_cpu(int nr)
generic_set_cpu_up(nr);
if (system_state == SYSTEM_RUNNING) {
+ /*
+ * To keep it compatible with old boot program which uses
+ * cache-inhibit spin table, we need to flush the cache
+ * before accessing spin table to invalidate any staled data.
+ * We also need to flush the cache after writing to spin
+ * table to push data out.
+ */
+ flush_spin_table(spin_table);
out_be32(&spin_table->addr_l, 0);
+ flush_spin_table(spin_table);
/*
* We don't set the BPTR register here since it already points
@@ -181,9 +203,14 @@ static int __cpuinit smp_85xx_kick_cpu(int nr)
*/
mpic_reset_core(hw_cpu);
- /* wait until core is ready... */
- if (!spin_event_timeout(in_be32(&spin_table->addr_l) == 1,
- 10000, 100)) {
+ /*
+ * wait until core is ready...
+ * We need to invalidate the stale data, in case the boot
+ * loader uses a cache-inhibited spin table.
+ */
+ if (!spin_event_timeout(
+ read_spin_table_addr_l(spin_table) == 1,
+ 10000, 100)) {
pr_err("%s: timeout waiting for core %d to reset\n",
__func__, hw_cpu);
ret = -ENOENT;
@@ -194,12 +221,10 @@ static int __cpuinit smp_85xx_kick_cpu(int nr)
__secondary_hold_acknowledge = -1;
}
#endif
+ flush_spin_table(spin_table);
out_be32(&spin_table->pir, hw_cpu);
out_be32(&spin_table->addr_l, __pa(__early_start));
-
- if (!ioremappable)
- flush_dcache_range((ulong)spin_table,
- (ulong)spin_table + sizeof(struct epapr_spin_table));
+ flush_spin_table(spin_table);
/* Wait a bit for the CPU to ack. */
if (!spin_event_timeout(__secondary_hold_acknowledge == hw_cpu,
@@ -213,13 +238,11 @@ out:
#else
smp_generic_kick_cpu(nr);
+ flush_spin_table(spin_table);
out_be32(&spin_table->pir, hw_cpu);
out_be64((u64 *)(&spin_table->addr_h),
__pa((u64)*((unsigned long long *)generic_secondary_smp_init)));
-
- if (!ioremappable)
- flush_dcache_range((ulong)spin_table,
- (ulong)spin_table + sizeof(struct epapr_spin_table));
+ flush_spin_table(spin_table);
#endif
local_irq_restore(flags);