[PATCH] ppc64: add log_rtas_error()

From: Nathan Fontenot <nfont@austin.ibm.com>

Add log_rtas_error(), to be called in the event that a rtas call
returns a hardware error (-1) so we can log additional information
about the hardware error.

diff --git a/arch/ppc64/kernel/rtas.c b/arch/ppc64/kernel/rtas.c
index 9a8d7def2861b2e59398c637a15e521ebac5b0fe..89b4d753409b76141a3ee061919085481ceb6fff 100644 (file)
--- a/arch/ppc64/kernel/rtas.c
+++ b/arch/ppc64/kernel/rtas.c
@@ -59,6 +59,8 @@ struct rtas_t rtas = {
        .lock = SPIN_LOCK_UNLOCKED
 };
 
+char rtas_err_buf[RTAS_ERROR_LOG_MAX];
+
 extern unsigned long reloc_offset(void);
 
 spinlock_t rtas_data_buf_lock = SPIN_LOCK_UNLOCKED;
@@ -126,6 +128,34 @@ rtas_token(const char *service)
        return tokp ? *tokp : RTAS_UNKNOWN_SERVICE;
 }
 
+void
+log_rtas_error(struct rtas_args        *rtas_args)
+{
+       struct rtas_args err_args;
+
+       err_args.token = rtas_token("rtas-last-error");
+       err_args.nargs = 2;
+       err_args.nret = 1;
+       err_args.rets = (rtas_arg_t *)&(err_args.args[2]);
+
+       err_args.args[0] = (rtas_arg_t)__pa(rtas_err_buf);
+       err_args.args[1] = RTAS_ERROR_LOG_MAX;
+       err_args.args[2] = 0;
+
+       get_paca()->xRtas = err_args;
+
+       PPCDBG(PPCDBG_RTAS, "\tentering rtas with 0x%lx\n",
+              (void *)__pa((unsigned long)&err_args));
+       enter_rtas((void *)__pa((unsigned long)&get_paca()->xRtas));
+       PPCDBG(PPCDBG_RTAS, "\treturned from rtas ...\n");
+
+       err_args = get_paca()->xRtas;
+       get_paca()->xRtas = *rtas_args;
+
+       if (err_args.rets[0] == 0)
+               log_error(rtas_err_buf, ERR_TYPE_RTAS_LOG, 0);
+}
+
 long
 rtas_call(int token, int nargs, int nret,
          unsigned long *outputs, ...)
@@ -166,6 +196,10 @@ rtas_call(int token, int nargs, int nret,
                (void *)__pa((unsigned long)rtas_args));
        enter_rtas((void *)__pa((unsigned long)rtas_args));
        PPCDBG(PPCDBG_RTAS, "\treturned from rtas ...\n");
+
+       if (rtas_args->rets[0] == -1)
+               log_rtas_error(rtas_args);
+
 #if 0   /* Gotta do something different here, use global lock for now... */
        spin_unlock_irqrestore(&rtas_args->lock, s);
 #else
@@ -410,9 +444,14 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
                return -EFAULT;
 
        spin_lock_irqsave(&rtas.lock, flags);
+
        get_paca()->xRtas = args;
        enter_rtas((void *)__pa((unsigned long)&get_paca()->xRtas));
        args = get_paca()->xRtas;
+
+       if (args.rets[0] == -1)
+               log_rtas_error(&args);
+
        spin_unlock_irqrestore(&rtas.lock, flags);
 
        /* Copy out args. */