X-Git-Url: http://git.ozo.com/?p=openwrt-10.03%2F.git;a=blobdiff_plain;f=target%2Flinux%2Far71xx%2Ffiles%2Farch%2Fmips%2Fpci%2Fpci-ar71xx.c;h=a75b9ab6861435be5c2f488dcaf7607cf9d37c93;hp=7d0eee9dbfb365a5c0bbf0c11a173bb84cf5a10f;hb=87fe054b87484f055ead8916fe64cbf806f10507;hpb=1e5d4a13be3871f726bdf162287d34aacd2f5ed1

diff --git a/target/linux/ar71xx/files/arch/mips/pci/pci-ar71xx.c b/target/linux/ar71xx/files/arch/mips/pci/pci-ar71xx.c
index 7d0eee9db..a75b9ab68 100644
--- a/target/linux/ar71xx/files/arch/mips/pci/pci-ar71xx.c
+++ b/target/linux/ar71xx/files/arch/mips/pci/pci-ar71xx.c
@@ -136,6 +136,7 @@ static int ar71xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
 	static u32 mask[8] = {0, 0xff, 0xffff, 0, 0xffffffff, 0, 0, 0};
 	unsigned long flags;
 	u32 data;
+	int retry = 0;
 	int ret;
 
 	ret = PCIBIOS_SUCCESSFUL;
@@ -143,6 +144,7 @@ static int ar71xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
 	DBG("PCI: read config: %02x:%02x.%01x/%02x:%01d\n", bus->number,
 			PCI_SLOT(devfn), PCI_FUNC(devfn), where, size);
 
+retry:
 	spin_lock_irqsave(&ar71xx_pci_lock, flags);
 
 	if (bus->number == 0 && devfn == 0) {
@@ -176,6 +178,14 @@ static int ar71xx_pci_read_config(struct pci_bus *bus, unsigned int devfn,
 
 	*value = (data >> (8 * (where & 3))) & mask[size & 7];
 
+	/*
+	 * PCI controller bug: sometimes reads to the PCI_COMMAND register
+	 * return 0xffff, even though the PCI trace shows the correct value.
+	 * Work around this by retrying reads to this register
+	 */
+	if (where == PCI_COMMAND && (*value & 0xffff) == 0xffff && retry++ < 2)
+		goto retry;
+
 	return ret;
 }