From 065b683618f8455dcb0bfc271a853d1c88a23734 Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Fri, 10 Jun 2016 21:44:26 -0500 Subject: soc/intel/common: don't infinitely recurse in busmaster_disable_on_bus() If a bridge has the primary bus equal to the secondary bus the busmaster_disable_on_bus() will infinitely call itself. Avoid the inifinite recursion by checking current bus number against the secondary bus number. BUG=chrome-os-partner:54262 TEST=Ran on reef. Able to actually get the chipset to assert SLP_Sx signals which means no more infinite recursion. Change-Id: I52b21fbba24e6a652ea8f9f87f5f49f60109c8f2 Signed-off-by: Aaron Durbin Reviewed-on: https://review.coreboot.org/15157 Reviewed-by: Furquan Shaikh Tested-by: build bot (Jenkins) --- src/soc/intel/common/smihandler.c | 23 ++++++++++++++++------- 1 file changed, 16 insertions(+), 7 deletions(-) (limited to 'src/soc/intel/common') diff --git a/src/soc/intel/common/smihandler.c b/src/soc/intel/common/smihandler.c index 0b220e201c..5915587b50 100644 --- a/src/soc/intel/common/smihandler.c +++ b/src/soc/intel/common/smihandler.c @@ -104,15 +104,24 @@ static void busmaster_disable_on_bus(int bus) reg32 &= ~PCI_COMMAND_MASTER; pci_write_config32(dev, PCI_COMMAND, reg32); - /* If this is a bridge, then follow it. */ + /* If it's not a bridge, move on. */ hdr = pci_read_config8(dev, PCI_HEADER_TYPE); hdr &= 0x7f; - if (hdr == PCI_HEADER_TYPE_BRIDGE || - hdr == PCI_HEADER_TYPE_CARDBUS) { - unsigned int buses; - buses = pci_read_config32(dev, PCI_PRIMARY_BUS); - busmaster_disable_on_bus((buses >> 8) & 0xff); - } + if (hdr != PCI_HEADER_TYPE_BRIDGE && + hdr != PCI_HEADER_TYPE_CARDBUS) + continue; + + /* + * If secondary bus is equal to current bus bypass + * the bridge because it's likely unconfigured and + * would cause infinite recursion. + */ + int secbus = pci_read_config8(dev, PCI_SECONDARY_BUS); + + if (secbus == bus) + continue; + + busmaster_disable_on_bus(secbus); } } } -- cgit v1.2.3