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Diffstat (limited to 'arch/powerpc/platforms/powernv/smp.c')
-rw-r--r--arch/powerpc/platforms/powernv/smp.c129
1 files changed, 84 insertions, 45 deletions
diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c
index 17210c526c5..5fcfcf44e3a 100644
--- a/arch/powerpc/platforms/powernv/smp.c
+++ b/arch/powerpc/platforms/powernv/smp.c
@@ -25,12 +25,14 @@
#include <asm/machdep.h>
#include <asm/cputable.h>
#include <asm/firmware.h>
-#include <asm/system.h>
#include <asm/rtas.h>
#include <asm/vdso_datapage.h>
#include <asm/cputhreads.h>
#include <asm/xics.h>
#include <asm/opal.h>
+#include <asm/runlatch.h>
+#include <asm/code-patching.h>
+#include <asm/dbell.h>
#include "powernv.h"
@@ -41,47 +43,88 @@
#define DBG(fmt...)
#endif
-static void __cpuinit pnv_smp_setup_cpu(int cpu)
+static void pnv_smp_setup_cpu(int cpu)
{
if (cpu != boot_cpuid)
xics_setup_cpu();
-}
-
-static int pnv_smp_cpu_bootable(unsigned int nr)
-{
- /* Special case - we inhibit secondary thread startup
- * during boot if the user requests it.
- */
- if (system_state < SYSTEM_RUNNING && cpu_has_feature(CPU_FTR_SMT)) {
- if (!smt_enabled_at_boot && cpu_thread_in_core(nr) != 0)
- return 0;
- if (smt_enabled_at_boot
- && cpu_thread_in_core(nr) >= smt_enabled_at_boot)
- return 0;
- }
- return 1;
+#ifdef CONFIG_PPC_DOORBELL
+ if (cpu_has_feature(CPU_FTR_DBELL))
+ doorbell_setup_this_cpu();
+#endif
}
-int __devinit pnv_smp_kick_cpu(int nr)
+int pnv_smp_kick_cpu(int nr)
{
unsigned int pcpu = get_hard_smp_processor_id(nr);
- unsigned long start_here = __pa(*((unsigned long *)
- generic_secondary_smp_init));
+ unsigned long start_here =
+ __pa(ppc_function_entry(generic_secondary_smp_init));
long rc;
BUG_ON(nr < 0 || nr >= NR_CPUS);
- /* On OPAL v2 the CPU are still spinning inside OPAL itself,
- * get them back now
+ /*
+ * If we already started or OPALv2 is not supported, we just
+ * kick the CPU via the PACA
+ */
+ if (paca[nr].cpu_start || !firmware_has_feature(FW_FEATURE_OPALv2))
+ goto kick;
+
+ /*
+ * At this point, the CPU can either be spinning on the way in
+ * from kexec or be inside OPAL waiting to be started for the
+ * first time. OPAL v3 allows us to query OPAL to know if it
+ * has the CPUs, so we do that
*/
- if (!paca[nr].cpu_start && firmware_has_feature(FW_FEATURE_OPALv2)) {
- pr_devel("OPAL: Starting CPU %d (HW 0x%x)...\n", nr, pcpu);
- rc = opal_start_cpu(pcpu, start_here);
- if (rc != OPAL_SUCCESS)
- pr_warn("OPAL Error %ld starting CPU %d\n",
+ if (firmware_has_feature(FW_FEATURE_OPALv3)) {
+ uint8_t status;
+
+ rc = opal_query_cpu_status(pcpu, &status);
+ if (rc != OPAL_SUCCESS) {
+ pr_warn("OPAL Error %ld querying CPU %d state\n",
rc, nr);
+ return -ENODEV;
+ }
+
+ /*
+ * Already started, just kick it, probably coming from
+ * kexec and spinning
+ */
+ if (status == OPAL_THREAD_STARTED)
+ goto kick;
+
+ /*
+ * Available/inactive, let's kick it
+ */
+ if (status == OPAL_THREAD_INACTIVE) {
+ pr_devel("OPAL: Starting CPU %d (HW 0x%x)...\n",
+ nr, pcpu);
+ rc = opal_start_cpu(pcpu, start_here);
+ if (rc != OPAL_SUCCESS) {
+ pr_warn("OPAL Error %ld starting CPU %d\n",
+ rc, nr);
+ return -ENODEV;
+ }
+ } else {
+ /*
+ * An unavailable CPU (or any other unknown status)
+ * shouldn't be started. It should also
+ * not be in the possible map but currently it can
+ * happen
+ */
+ pr_devel("OPAL: CPU %d (HW 0x%x) is unavailable"
+ " (status %d)...\n", nr, pcpu, status);
+ return -ENODEV;
+ }
+ } else {
+ /*
+ * On OPAL v2, we just kick it and hope for the best,
+ * we must not test the error from opal_start_cpu() or
+ * we would fail to get CPUs from kexec.
+ */
+ opal_start_cpu(pcpu, start_here);
}
+ kick:
return smp_generic_kick_cpu(nr);
}
@@ -107,14 +150,6 @@ static void pnv_smp_cpu_kill_self(void)
{
unsigned int cpu;
- /* If powersave_nap is enabled, use NAP mode, else just
- * spin aimlessly
- */
- if (!powersave_nap) {
- generic_mach_cpu_die();
- return;
- }
-
/* Standard hot unplug procedure */
local_irq_disable();
idle_task_exit();
@@ -129,16 +164,20 @@ static void pnv_smp_cpu_kill_self(void)
*/
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1);
while (!generic_check_cpu_restart(cpu)) {
- power7_idle();
- if (!generic_check_cpu_restart(cpu)) {
+ ppc64_runlatch_off();
+ power7_nap(1);
+ ppc64_runlatch_on();
+
+ /* Reenable IRQs briefly to clear the IPI that woke us */
+ local_irq_enable();
+ local_irq_disable();
+ mb();
+
+ if (cpu_core_split_required())
+ continue;
+
+ if (!generic_check_cpu_restart(cpu))
DBG("CPU%d Unexpected exit while offline !\n", cpu);
- /* We may be getting an IPI, so we re-enable
- * interrupts to process it, it will be ignored
- * since we aren't online (hopefully)
- */
- local_irq_enable();
- local_irq_disable();
- }
}
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);
DBG("CPU%d coming online...\n", cpu);
@@ -152,7 +191,7 @@ static struct smp_ops_t pnv_smp_ops = {
.probe = xics_smp_probe,
.kick_cpu = pnv_smp_kick_cpu,
.setup_cpu = pnv_smp_setup_cpu,
- .cpu_bootable = pnv_smp_cpu_bootable,
+ .cpu_bootable = smp_generic_cpu_bootable,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_disable = pnv_smp_cpu_disable,
.cpu_die = generic_cpu_die,