[PATCH] powerpc/fsl-pci: Fix MSI support on 83xx platforms

[Kumar Gala <galak@kernel.crashing.org>]

The following commit broke 83xx because it assumed the 83xx platforms
exposed the "IMMR" address in BAR0 like the 85xx/86xx/QoriQ devices do:

commit 3da34aae03d498ee62f75aa7467de93cce3030fd
Author: Kumar Gala <galak@kernel.crashing.org>
Date:   Tue May 12 15:51:56 2009 -0500

    powerpc/fsl: Support unique MSI addresses per PCIe Root Complex

However that is not true, so we have to search through the inbound
window settings on 83xx to find which one matches the IMMR address to
determine its PCI address.

Reported-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
---
 arch/powerpc/sysdev/fsl_msi.c |    9 +++----
 arch/powerpc/sysdev/fsl_pci.c |   43 ++++++++++++++++++++++++++++++++++++++++-
 arch/powerpc/sysdev/fsl_pci.h |    1 +
 3 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c
index 962c2d8..dcd244d 100644
--- a/arch/powerpc/sysdev/fsl_msi.c
+++ b/arch/powerpc/sysdev/fsl_msi.c
@@ -24,6 +24,7 @@
 #include <asm/ppc-pci.h>
 #include <asm/mpic.h>
 #include "fsl_msi.h"
+#include "fsl_pci.h"
 
 LIST_HEAD(msi_head);
 
@@ -125,13 +126,11 @@ static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
 {
 	struct fsl_msi *msi_data = fsl_msi_data;
 	struct pci_controller *hose = pci_bus_to_host(pdev->bus);
-	u32 base = 0;
+	u64 base = fsl_pci_immrbar_base(hose);
 
-	pci_bus_read_config_dword(hose->bus,
-		PCI_DEVFN(0, 0), PCI_BASE_ADDRESS_0, &base);
+	msg->address_lo = msi_data->msi_addr_lo + lower_32_bits(base);
+	msg->address_hi = msi_data->msi_addr_hi + upper_32_bits(base);
 
-	msg->address_lo = msi_data->msi_addr_lo + base;
-	msg->address_hi = msi_data->msi_addr_hi;
 	msg->data = hwirq;
 
 	pr_debug("%s: allocated srs: %d, ibs: %d\n",
diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index 7e900ec..0c28d93 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -1,7 +1,7 @@
 /*
  * MPC83xx/85xx/86xx PCI/PCIE support routing.
  *
- * Copyright 2007-2009 Freescale Semiconductor, Inc.
+ * Copyright 2007-2010 Freescale Semiconductor, Inc.
  * Copyright 2008-2009 MontaVista Software, Inc.
  *
  * Initial author: Xianghua Xiao <x.xiao@freescale.com>
@@ -310,6 +310,16 @@ void fsl_pcibios_fixup_bus(struct pci_bus *bus)
 	}
 }
 
+u64 fsl_pci_immrbar_base(struct pci_controller *hose)
+{
+	u32 base;
+
+	pci_bus_read_config_dword(hose->bus,
+		PCI_DEVFN(0, 0), PCI_BASE_ADDRESS_0, &base);
+
+	return base;
+}
+
 int __init fsl_add_bridge(struct device_node *dev, int is_primary)
 {
 	int len;
@@ -428,6 +438,13 @@ struct mpc83xx_pcie_priv {
 	u32 dev_base;
 };
 
+struct pex_inbound_window {
+	u32 ar;
+	u32 tar;
+	u32 barl;
+	u32 barh;
+};
+
 /*
  * With the convention of u-boot, the PCIE outbound window 0 serves
  * as configuration transactions outbound.
@@ -435,6 +452,8 @@ struct mpc83xx_pcie_priv {
 #define PEX_OUTWIN0_BAR		0xCA4
 #define PEX_OUTWIN0_TAL		0xCA8
 #define PEX_OUTWIN0_TAH		0xCAC
+#define PEX_RC_INWIN_BASE	0xE60
+#define PEX_RCIWARn_EN		0x1
 
 static int mpc83xx_pcie_exclude_device(struct pci_bus *bus, unsigned int devfn)
 {
@@ -461,6 +480,28 @@ static int mpc83xx_pcie_exclude_device(struct pci_bus *bus, unsigned int devfn)
 	return PCIBIOS_SUCCESSFUL;
 }
 
+/* Walk the Root Complex Inbound windows to match IMMR base */
+u64 fsl_pci_immrbar_base(struct pci_controller *hose)
+{
+	struct mpc83xx_pcie_priv *pcie = hose->dn->data;
+	struct pex_inbound_window *in = pcie->cfg_type0 + PEX_RC_INWIN_BASE;
+	int i;
+
+	for (i = 0; i < 4; i++) {
+		/* not enabled, skip */
+		if (!in_le32(&in[i].ar) & PEX_RCIWARn_EN)
+			 continue;
+
+		if (get_immrbase() == in_le32(&in[i].tar))
+			return (u64)in_le32(&in[i].barh) << 32 |
+				    in_le32(&in[i].barl);
+	}
+
+	printk(KERN_WARNING "could not find PCI BAR matching IMMR\n");
+
+	return 0;
+}
+
 static void __iomem *mpc83xx_pcie_remap_cfg(struct pci_bus *bus,
 					    unsigned int devfn, int offset)
 {
diff --git a/arch/powerpc/sysdev/fsl_pci.h b/arch/powerpc/sysdev/fsl_pci.h
index a9d8bbe..8ad72a1 100644
--- a/arch/powerpc/sysdev/fsl_pci.h
+++ b/arch/powerpc/sysdev/fsl_pci.h
@@ -88,6 +88,7 @@ struct ccsr_pci {
 extern int fsl_add_bridge(struct device_node *dev, int is_primary);
 extern void fsl_pcibios_fixup_bus(struct pci_bus *bus);
 extern int mpc83xx_add_bridge(struct device_node *dev);
+u64 fsl_pci_immrbar_base(struct pci_controller *hose);
 
 #endif /* __POWERPC_FSL_PCI_H */
 #endif /* __KERNEL__ */
-- 
1.6.0.6