[POWERPC] Add powerpc PCI-E reset API implementation

Adds the pSeries platform implementation for a new PCI API
which can be used to issue various types of PCI-E reset,
including PCI-E warm reset and PCI-E hot reset. This is needed
for an ipr PCI-E adapter which does not properly implement BIST.
Running BIST on this adapter results in PCI-E errors. The only
reliable reset mechanism that exists on this hardware is PCI
Fundamental reset (warm reset).

Acked-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c
index 48fbd442e9df..63e23062e982 100644
--- a/arch/powerpc/platforms/pseries/eeh.c
+++ b/arch/powerpc/platforms/pseries/eeh.c
@@ -580,6 +580,36 @@ rtas_pci_slot_reset(struct pci_dn *pdn, int state)
 }
 
 /**
+ * pcibios_set_pcie_slot_reset - Set PCI-E reset state
+ * @dev:        pci device struct
+ * @state:      reset state to enter
+ *
+ * Return value:
+ *      0 if success
+ **/
+int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)
+{
+        struct device_node *dn = pci_device_to_OF_node(dev);
+        struct pci_dn *pdn = PCI_DN(dn);
+
+        switch (state) {
+        case pcie_deassert_reset:
+                rtas_pci_slot_reset(pdn, 0);
+                break;
+        case pcie_hot_reset:
+                rtas_pci_slot_reset(pdn, 1);
+                break;
+        case pcie_warm_reset:
+                rtas_pci_slot_reset(pdn, 3);
+                break;
+        default:
+                return -EINVAL;
+        };
+
+        return 0;
+}
+
+/**
  * rtas_set_slot_reset -- assert the pci #RST line for 1/4 second
  * @pdn: pci device node to be reset.
  *