From e8a1451e368e74403b56d557a94b39c0948fa8c1 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sat, 4 Dec 2010 01:32:15 +0000 Subject: [PATCH] ar71xx: work around a PCI controller bug which causes reads to the PCI_COMMAND register to return bogus values - properly fixes ath9k module reload issues SVN-Revision: 24236 --- .../mac80211/patches/520-ath9k_pci_error_fix.patch | 13 ------------- .../linux/ar71xx/files/arch/mips/pci/pci-ar71xx.c | 10 ++++++++++ 2 files changed, 10 insertions(+), 13 deletions(-) delete mode 100644 package/mac80211/patches/520-ath9k_pci_error_fix.patch diff --git a/package/mac80211/patches/520-ath9k_pci_error_fix.patch b/package/mac80211/patches/520-ath9k_pci_error_fix.patch deleted file mode 100644 index b8fcc994b6..0000000000 --- a/package/mac80211/patches/520-ath9k_pci_error_fix.patch +++ /dev/null @@ -1,13 +0,0 @@ ---- a/drivers/net/wireless/ath/ath9k/pci.c -+++ b/drivers/net/wireless/ath/ath9k/pci.c -@@ -255,6 +255,10 @@ static void ath_pci_remove(struct pci_de - struct ath_wiphy *aphy = hw->priv; - struct ath_softc *sc = aphy->sc; - void __iomem *mem = sc->mem; -+ u16 val; -+ -+ /* Do a config read to clear pre-existing pci error status */ -+ pci_read_config_word(pdev, PCI_COMMAND, &val); - - ath9k_deinit_device(sc); - free_irq(sc->irq, sc); 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 c6c6e55834..5f10d6a652 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; } -- 2.30.2