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-rw-r--r--arch/powerpc/kernel/rtas.c99
1 files changed, 58 insertions, 41 deletions
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 214780798289..52e95c2158c0 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -19,6 +19,9 @@
#include <linux/init.h>
#include <linux/capability.h>
#include <linux/delay.h>
+#include <linux/smp.h>
+#include <linux/completion.h>
+#include <linux/cpumask.h>
#include <asm/prom.h>
#include <asm/rtas.h>
@@ -34,6 +37,8 @@
#include <asm/lmb.h>
#include <asm/udbg.h>
#include <asm/syscalls.h>
+#include <asm/smp.h>
+#include <asm/atomic.h>
struct rtas_t rtas = {
.lock = SPIN_LOCK_UNLOCKED
@@ -41,8 +46,10 @@ struct rtas_t rtas = {
EXPORT_SYMBOL(rtas);
struct rtas_suspend_me_data {
- long waiting;
- struct rtas_args *args;
+ atomic_t working; /* number of cpus accessing this struct */
+ int token; /* ibm,suspend-me */
+ int error;
+ struct completion *complete; /* wait on this until working == 0 */
};
DEFINE_SPINLOCK(rtas_data_buf_lock);
@@ -657,50 +664,62 @@ static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
#ifdef CONFIG_PPC_PSERIES
static void rtas_percpu_suspend_me(void *info)
{
- int i;
long rc;
- long flags;
+ unsigned long msr_save;
+ int cpu;
struct rtas_suspend_me_data *data =
(struct rtas_suspend_me_data *)info;
- /*
- * We use "waiting" to indicate our state. As long
- * as it is >0, we are still trying to all join up.
- * If it goes to 0, we have successfully joined up and
- * one thread got H_CONTINUE. If any error happens,
- * we set it to <0.
- */
- local_irq_save(flags);
- do {
- rc = plpar_hcall_norets(H_JOIN);
- smp_rmb();
- } while (rc == H_SUCCESS && data->waiting > 0);
- if (rc == H_SUCCESS)
- goto out;
+ atomic_inc(&data->working);
+
+ /* really need to ensure MSR.EE is off for H_JOIN */
+ msr_save = mfmsr();
+ mtmsr(msr_save & ~(MSR_EE));
+
+ rc = plpar_hcall_norets(H_JOIN);
+
+ mtmsr(msr_save);
- if (rc == H_CONTINUE) {
- data->waiting = 0;
- data->args->args[data->args->nargs] =
- rtas_call(ibm_suspend_me_token, 0, 1, NULL);
- for_each_possible_cpu(i)
- plpar_hcall_norets(H_PROD,i);
+ if (rc == H_SUCCESS) {
+ /* This cpu was prodded and the suspend is complete. */
+ goto out;
+ } else if (rc == H_CONTINUE) {
+ /* All other cpus are in H_JOIN, this cpu does
+ * the suspend.
+ */
+ printk(KERN_DEBUG "calling ibm,suspend-me on cpu %i\n",
+ smp_processor_id());
+ data->error = rtas_call(data->token, 0, 1, NULL);
+
+ if (data->error)
+ printk(KERN_DEBUG "ibm,suspend-me returned %d\n",
+ data->error);
} else {
- data->waiting = -EBUSY;
- printk(KERN_ERR "Error on H_JOIN hypervisor call\n");
+ printk(KERN_ERR "H_JOIN on cpu %i failed with rc = %ld\n",
+ smp_processor_id(), rc);
+ data->error = rc;
}
-
+ /* This cpu did the suspend or got an error; in either case,
+ * we need to prod all other other cpus out of join state.
+ * Extra prods are harmless.
+ */
+ for_each_online_cpu(cpu)
+ plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
out:
- local_irq_restore(flags);
- return;
+ if (atomic_dec_return(&data->working) == 0)
+ complete(data->complete);
}
static int rtas_ibm_suspend_me(struct rtas_args *args)
{
- int i;
long state;
long rc;
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
struct rtas_suspend_me_data data;
+ DECLARE_COMPLETION_ONSTACK(done);
+
+ if (!rtas_service_present("ibm,suspend-me"))
+ return -ENOSYS;
/* Make sure the state is valid */
rc = plpar_hcall(H_VASI_STATE, retbuf,
@@ -721,25 +740,23 @@ static int rtas_ibm_suspend_me(struct rtas_args *args)
return 0;
}
- data.waiting = 1;
- data.args = args;
+ atomic_set(&data.working, 0);
+ data.token = rtas_token("ibm,suspend-me");
+ data.error = 0;
+ data.complete = &done;
/* Call function on all CPUs. One of us will make the
* rtas call
*/
if (on_each_cpu(rtas_percpu_suspend_me, &data, 1, 0))
- data.waiting = -EINVAL;
+ data.error = -EINVAL;
- if (data.waiting != 0)
- printk(KERN_ERR "Error doing global join\n");
+ wait_for_completion(&done);
- /* Prod each CPU. This won't hurt, and will wake
- * anyone we successfully put to sleep with H_JOIN.
- */
- for_each_possible_cpu(i)
- plpar_hcall_norets(H_PROD, i);
+ if (data.error != 0)
+ printk(KERN_ERR "Error doing global join\n");
- return data.waiting;
+ return data.error;
}
#else /* CONFIG_PPC_PSERIES */
static int rtas_ibm_suspend_me(struct rtas_args *args)