1 files changed, 16 insertions, 3 deletions

diff --git a/arch/powerpc/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c
index da6e5362e7cd..9437f48cc9e7 100644
--- a/arch/powerpc/platforms/pseries/eeh.c
+++ b/arch/powerpc/platforms/pseries/eeh.c
@@ -747,6 +747,7 @@ struct eeh_early_enable_info {
 /* Enable eeh for the given device node. */
 static void *early_enable_eeh(struct device_node *dn, void *data)
 {
+        unsigned int rets[3];
         struct eeh_early_enable_info *info = data;
         int ret;
         const char *status = get_property(dn, "status", NULL);
@@ -803,16 +804,14 @@ static void *early_enable_eeh(struct device_node *dn, void *data)
                                 regs[0], info->buid_hi, info->buid_lo,
                                 EEH_ENABLE);
 
+                enable = 0;
                 if (ret == 0) {
-                        eeh_subsystem_enabled = 1;
-                        pdn->eeh_mode |= EEH_MODE_SUPPORTED;
                         pdn->eeh_config_addr = regs[0];
 
                         /* If the newer, better, ibm,get-config-addr-info is supported, 
                          * then use that instead. */
                         pdn->eeh_pe_config_addr = 0;
                         if (ibm_get_config_addr_info != RTAS_UNKNOWN_SERVICE) {
-                                unsigned int rets[2];
                                 ret = rtas_call (ibm_get_config_addr_info, 4, 2, rets, 
                                         pdn->eeh_config_addr, 
                                         info->buid_hi, info->buid_lo,
@@ -820,6 +819,20 @@ static void *early_enable_eeh(struct device_node *dn, void *data)
                                 if (ret == 0)
                                         pdn->eeh_pe_config_addr = rets[0];
                         }
+
+                        /* Some older systems (Power4) allow the
+                         * ibm,set-eeh-option call to succeed even on nodes
+                         * where EEH is not supported. Verify support
+                         * explicitly. */
+                        ret = read_slot_reset_state(pdn, rets);
+                        if ((ret == 0) && (rets[1] == 1))
+                                enable = 1;
+                }
+
+                if (enable) {
+                        eeh_subsystem_enabled = 1;
+                        pdn->eeh_mode |= EEH_MODE_SUPPORTED;
+
 #ifdef DEBUG
                         printk(KERN_DEBUG "EEH: %s: eeh enabled, config=%x pe_config=%x\n",
                                dn->full_name, pdn->eeh_config_addr, pdn->eeh_pe_config_addr);