From: Kevin O'Connor Date: Wed, 14 Oct 2009 23:28:04 +0000 (-0400) Subject: fix low bits in ROM and I/O sizing X-Git-Tag: rel-0.5.0~57 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=2f442fd566d683253cf23560867a34243c185550;p=seabios.git fix low bits in ROM and I/O sizing This cleans up handling of low bits during BAR sizing, to match PCI spec requirements, and to use symbolic constants from pci_regs.h Issues fixed: For ROM BARs, bit 0 is writeable (enable bit), which we not only don't want to set, but it will stick and make us think it's an I/O port resource. Further, PCI spec defines the following bits as reserved: - bit 1 in I/O BAR - bits 10:1 in ROM BAR and we should be careful and preserve any values there, and should ignore anything we read from these registers. Bits 3:2 in I/O BAR might be writeable, so it is wrong to mask them when calculating BAR size. Spec references: See 6.2.5.1 for I/O and memory, and 6.2.5.2 for ROM, 6.1 for reserved bit handling; pages 225, 228 and 214 in PCI spec revision 3.0. See also Qemu pcbios commit 6ddb9f5c742b2b82b1755d7ec2a127f6e20e3806 Signed-off-by: Gleb Natapov Signed-off-by: Michael S. Tsirkin --- diff --git a/src/pciinit.c b/src/pciinit.c index 71177bc..39c8f0f 100644 --- a/src/pciinit.c +++ b/src/pciinit.c @@ -126,16 +126,28 @@ static void pci_bios_init_device(u16 bdf) /* default memory mappings */ for (i = 0; i < PCI_NUM_REGIONS; i++) { int ofs; - u32 val, size; - + u32 old, val, mask, size; if (i == PCI_ROM_SLOT) ofs = PCI_ROM_ADDRESS; else ofs = PCI_BASE_ADDRESS_0 + i * 4; - pci_config_writel(bdf, ofs, 0xffffffff); + + old = pci_config_readl(bdf, ofs); + if (i == PCI_ROM_SLOT) { + mask = PCI_ROM_ADDRESS_MASK; + pci_config_writel(bdf, ofs, mask); + } else { + if (val & PCI_BASE_ADDRESS_SPACE_IO) + mask = PCI_BASE_ADDRESS_IO_MASK; + else + mask = PCI_BASE_ADDRESS_MEM_MASK; + pci_config_writel(bdf, ofs, ~0); + } val = pci_config_readl(bdf, ofs); + pci_config_writel(bdf, ofs, old); + if (val != 0) { - size = (~(val & ~0xf)) + 1; + size = (~(val & mask)) + 1; if (val & PCI_BASE_ADDRESS_SPACE_IO) paddr = &pci_bios_io_addr; else if (size >= 0x04000000)