powerpc/eeh: pseries platform config space access in EEH

With the original EEH implementation, the access to config space of
the corresponding PCI device is done by RTAS sensitive function. That
depends on pci_dn heavily. That would limit EEH extension to other
platforms like powernv because other platforms might have different
ways to access PCI config space.

The patch splits those functions used to access PCI config space
and implement them in platform related EEH component. It would be
helpful to support EEH on multiple platforms simutaneously in future.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 39 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/pseries/eeh_pseries.c b/arch/powerpc/platforms/pseries/eeh_pseries.c
index 36a1af1d1140..8752f79a6af8 100644
--- a/arch/powerpc/platforms/pseries/eeh_pseries.c
+++ b/arch/powerpc/platforms/pseries/eeh_pseries.c
@@ -503,6 +503,42 @@ static int pseries_eeh_configure_bridge(struct device_node *dn)
 	return ret;
 }
 
+/**
+ * pseries_eeh_read_config - Read PCI config space
+ * @dn: device node
+ * @where: PCI address
+ * @size: size to read
+ * @val: return value
+ *
+ * Read config space from the speicifed device
+ */
+static int pseries_eeh_read_config(struct device_node *dn, int where, int size, u32 *val)
+{
+	struct pci_dn *pdn;
+
+	pdn = PCI_DN(dn);
+
+	return rtas_read_config(pdn, where, size, val);
+}
+
+/**
+ * pseries_eeh_write_config - Write PCI config space
+ * @dn: device node
+ * @where: PCI address
+ * @size: size to write
+ * @val: value to be written
+ *
+ * Write config space to the specified device
+ */
+static int pseries_eeh_write_config(struct device_node *dn, int where, int size, u32 val)
+{
+	struct pci_dn *pdn;
+
+	pdn = PCI_DN(dn);
+
+	return rtas_write_config(pdn, where, size, val);
+}
+
 static struct eeh_ops pseries_eeh_ops = {
 	.name			= "pseries",
 	.init			= pseries_eeh_init,
@@ -512,7 +548,9 @@ static struct eeh_ops pseries_eeh_ops = {
 	.reset			= pseries_eeh_reset,
 	.wait_state		= pseries_eeh_wait_state,
 	.get_log		= pseries_eeh_get_log,
-	.configure_bridge	= pseries_eeh_configure_bridge
+	.configure_bridge       = pseries_eeh_configure_bridge,
+	.read_config		= pseries_eeh_read_config,
+	.write_config		= pseries_eeh_write_config
 };
 
 /**