From 808e34e2cd6bc74a2311b6a00d12a52e37fb50c0 Mon Sep 17 00:00:00 2001 From: Zoltan Kiss Date: Thu, 22 Aug 2013 23:19:18 +0100 Subject: PCI: Disable decoding for BAR sizing only when it was actually enabled We disable BARs while sizing them so we don't cause conflicts with other devices (see 253d2e5498 and bbffe43524). But if device decoding is already disabled before we size the BAR, we don't need to disable it again. [bhelgaas: changelog, add PCI_COMMAND_DECODING_ENABLE for readability] Signed-off-by: Zoltan Kiss Signed-off-by: Bjorn Helgaas --- drivers/pci/probe.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index cf57fe79450a..b50386dc72e0 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -156,6 +156,8 @@ static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar) return flags; } +#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO) + /** * pci_read_base - read a PCI BAR * @dev: the PCI device @@ -178,8 +180,10 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type, /* No printks while decoding is disabled! */ if (!dev->mmio_always_on) { pci_read_config_word(dev, PCI_COMMAND, &orig_cmd); - pci_write_config_word(dev, PCI_COMMAND, - orig_cmd & ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO)); + if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) { + pci_write_config_word(dev, PCI_COMMAND, + orig_cmd & ~PCI_COMMAND_DECODE_ENABLE); + } } res->name = pci_name(dev); @@ -293,7 +297,8 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type, fail: res->flags = 0; out: - if (!dev->mmio_always_on) + if (!dev->mmio_always_on && + (orig_cmd & PCI_COMMAND_DECODE_ENABLE)) pci_write_config_word(dev, PCI_COMMAND, orig_cmd); if (bar_too_big) -- cgit v1.2.3