diff options
| author | Andrew Isaacson <adi@broadcom.com> | 2005-10-20 08:59:46 +0200 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2005-10-29 20:32:49 +0200 |
| commit | cb4262481fce1d43ac9a483be4faf36fdd1c7abb (patch) | |
| tree | 04e3614f81b2ac7b3091969427160de127f8d4c3 /arch | |
| parent | BCM1480 HT support (diff) | |
| download | linux-cb4262481fce1d43ac9a483be4faf36fdd1c7abb.tar.xz linux-cb4262481fce1d43ac9a483be4faf36fdd1c7abb.zip | |
pci-expmem-hack
CFE 1.2.5 and earlier fails to turn on the ExpMemEn bit in the
PCIFeatureControl register, which means that DMA does not work
beyond physical address 01_0000_0000, ergo to DRAM beyond 1GB.
With ExpMemEn turned on, 01_0000_0000-0f_ffff_ffff is mapped,
so DMA works for up to 61 GB of DRAM.
Will be fixed in CFE 1.2.6 (yet to be released).
Signed-Off-By: Andy Isaacson <adi@broadcom.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/pci/pci-bcm1480.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/mips/pci/pci-bcm1480.c b/arch/mips/pci/pci-bcm1480.c index 4905d8593d6d..f194b4e4f86a 100644 --- a/arch/mips/pci/pci-bcm1480.c +++ b/arch/mips/pci/pci-bcm1480.c @@ -232,6 +232,14 @@ static int __init bcm1480_pcibios_init(void) bcm1480_bus_status |= PCI_BUS_ENABLED; } + /* turn on ExpMemEn */ + cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40)); + printk("PCIFeatureCtrl = %x\n", cmdreg); + WRITECFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40), + cmdreg | 0x10); + cmdreg = READCFG32(CFGOFFSET(0, PCI_DEVFN(PCI_BRIDGE_DEVICE, 0), 0x40)); + printk("PCIFeatureCtrl = %x\n", cmdreg); + /* * Establish mappings in KSEG2 (kernel virtual) to PCI I/O * space. Use "match bytes" policy to make everything look |