[PATCH 04/10] powerpc/eeh: Backends to get/set settings

[Gavin Shan <shangw@linux.vnet.ibm.com>]

When the PHB gets fenced, 0xFF's returns from PCI config space and
MMIO space in the hardware. The operations writting to them should
be dropped. The patch introduce backends allow to set/get flags that
indicate the access to PCI-CFG and MMIO should be blocked.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/eeh.h               |    6 +++
 arch/powerpc/platforms/pseries/eeh_pseries.c |   44 ++++++++++++++++++++++++++
 2 files changed, 50 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index dd65e31..de821c1 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -131,6 +131,10 @@ static inline struct pci_dev *eeh_dev_to_pci_dev(struct eeh_dev *edev)
 #define EEH_LOG_TEMP		1	/* EEH temporary error log	*/
 #define EEH_LOG_PERM		2	/* EEH permanent error log	*/
 
+/* Settings for platforms */
+#define EEH_SETTING_BLOCK_CFG	1	/* Blocked PCI config access	*/
+#define EEH_SETTING_BLOCK_IO	2	/* Blocked MMIO access		*/
+
 struct eeh_ops {
 	char *name;
 	int (*init)(void);
@@ -146,6 +150,8 @@ struct eeh_ops {
 	int (*configure_bridge)(struct eeh_pe *pe);
 	int (*read_config)(struct device_node *dn, int where, int size, u32 *val);
 	int (*write_config)(struct device_node *dn, int where, int size, u32 val);
+	int (*get_setting)(int option, int *value, void *data);
+	int (*set_setting)(int option, int value, void *data);
 	int (*next_error)(struct eeh_pe **pe);
 };
 
diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c
index 62415f2..8c9509b 100644
--- a/arch/powerpc/platforms/pseries/eeh_pseries.c
+++ b/arch/powerpc/platforms/pseries/eeh_pseries.c
@@ -612,6 +612,48 @@ static int pseries_eeh_write_config(struct device_node *dn, int where, int size,
 	return rtas_write_config(pdn, where, size, val);
 }
 
+/**
+ * pseries_eeh_get_setting - Retrieve settings that affect EEH core
+ * @option: option
+ * @value: value
+ * @data: dependent data
+ *
+ * Retrieve the settings from the platform in order to affect the
+ * behaviour of EEH core. We don't block PCI config or MMIO access
+ * on pSeries platform.
+ */
+static int pseries_eeh_get_setting(int option, int *value, void *data)
+{
+	int ret = 0;
+
+	switch (option) {
+	case EEH_SETTING_BLOCK_CFG:
+	case EEH_SETTING_BLOCK_IO:
+		*value = 0;
+		break;
+	default:
+		pr_warning("%s: Unrecognized option (%d)\n",
+			   __func__, option);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+/**
+ * pseries_eeh_set_setting - Configure settings to affect EEH core
+ * @option: option
+ * @value: value
+ * @data: dependent data
+ *
+ * Configure the settings for the platform in order to affect the
+ * behaviour of EEH core.
+ */
+static int pseries_eeh_set_setting(int option, int value, void *data)
+{
+	return 0;
+}
+
 static struct eeh_ops pseries_eeh_ops = {
 	.name			= "pseries",
 	.init			= pseries_eeh_init,
@@ -626,6 +668,8 @@ static struct eeh_ops pseries_eeh_ops = {
 	.configure_bridge       = pseries_eeh_configure_bridge,
 	.read_config		= pseries_eeh_read_config,
 	.write_config		= pseries_eeh_write_config,
+	.get_setting		= pseries_eeh_get_setting,
+	.set_setting		= pseries_eeh_set_setting,
 	.next_error		= NULL
 };
 
-- 
1.7.5.4