diff options
Diffstat (limited to 'arch/powerpc/kernel/rtas.c')
| -rw-r--r-- | arch/powerpc/kernel/rtas.c | 99 |
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) |