Subject: [PATCH 04/25] [POWERPC] Added indirect quirk to handle PCIe PHB that have issue w/no link

From: Kumar Gala <[email-masked]>
Date: Mon, 23 Jul 2007 15:49:51 -0500

Added PPC_INDIRECT_TYPE_NO_PCIE_LINK flag to the indirect pci handling
code to ensure that we don't talk to any device other than the PHB
if we don't have PCIe link.  Some controllers will lockup if they try
to do a config cycle to any device on the bus except the PHB.

Signed-off-by: Kumar Gala <[email-masked]>
---
 arch/powerpc/sysdev/indirect_pci.c |   16 +++++++++++++++-
 include/asm-powerpc/pci-bridge.h   |    5 +++++
 2 files changed, 20 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/sysdev/indirect_pci.c b/arch/powerpc/sysdev/indirect_pci.c
index c7e6e85..bc5b4e2 100644
--- a/arch/powerpc/sysdev/indirect_pci.c
+++ b/arch/powerpc/sysdev/indirect_pci.c
@@ -35,10 +35,17 @@ indirect_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
 	u8 cfg_type = 0;
 	u32 bus_no, reg;
 
+	if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
+		if (bus->number != hose->first_busno)
+			return PCIBIOS_DEVICE_NOT_FOUND;
+		if (devfn != 0)
+			return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
 	if (ppc_md.pci_exclude_device)
 		if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
 			return PCIBIOS_DEVICE_NOT_FOUND;
-	
+
 	if (hose->indirect_type & PPC_INDIRECT_TYPE_SET_CFG_TYPE)
 		if (bus->number != hose->first_busno)
 			cfg_type = 1;
@@ -83,6 +90,13 @@ indirect_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
 	u8 cfg_type = 0;
 	u32 bus_no, reg;
 
+	if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
+		if (bus->number != hose->first_busno)
+			return PCIBIOS_DEVICE_NOT_FOUND;
+		if (devfn != 0)
+			return PCIBIOS_DEVICE_NOT_FOUND;
+	}
+
 	if (ppc_md.pci_exclude_device)
 		if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
 			return PCIBIOS_DEVICE_NOT_FOUND;
diff --git a/include/asm-powerpc/pci-bridge.h b/include/asm-powerpc/pci-bridge.h
index 7a00b8e..9754357 100644
--- a/include/asm-powerpc/pci-bridge.h
+++ b/include/asm-powerpc/pci-bridge.h
@@ -45,10 +45,15 @@ struct pci_controller {
 	 *   on Freescale PCI-e controllers since they used the PCI_PRIMARY_BUS
 	 *   to determine which bus number to match on when generating type0
 	 *   config cycles
+	 *  NO_PCIE_LINK - the Freescale PCI-e controllers have issues with
+	 *   hanging if we don't have link and try to do config cycles to
+	 *   anything but the PHB.  Only allow talking to the PHB if this is
+	 *   set.
 	 */
 #define PPC_INDIRECT_TYPE_SET_CFG_TYPE		(0x00000001)
 #define PPC_INDIRECT_TYPE_EXT_REG		(0x00000002)
 #define PPC_INDIRECT_TYPE_SURPRESS_PRIMARY_BUS	(0x00000004)
+#define PPC_INDIRECT_TYPE_NO_PCIE_LINK		(0x00000008)
 	u32 indirect_type;
 
 	/* Currently, we limit ourselves to 1 IO range and 3 mem
-- 
1.5.2.2