Hi Simon,
On Sun, Dec 28, 2014 at 10:20 AM, Simon Glass sjg@chromium.org wrote:
Set the frame buffer to write-combining. This makes it faster, although for scrolling write-through is even faster for U-Boot.
Signed-off-by: Simon Glass sjg@chromium.org
arch/x86/cpu/ivybridge/gma.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/arch/x86/cpu/ivybridge/gma.c b/arch/x86/cpu/ivybridge/gma.c index 125021b..03b2ebd 100644 --- a/arch/x86/cpu/ivybridge/gma.c +++ b/arch/x86/cpu/ivybridge/gma.c @@ -12,6 +12,7 @@ #include <fdtdec.h> #include <pci_rom.h> #include <asm/io.h> +#include <asm/mtrr.h> #include <asm/pci.h> #include <asm/arch/pch.h> #include <asm/arch/sandybridge.h> @@ -738,6 +739,8 @@ int gma_func0_init(pci_dev_t dev, struct pci_controller *hose, const void *blob, int node) { void *gtt_bar;
ulong start;ulong base; u32 reg32; int ret;@@ -746,6 +749,11 @@ int gma_func0_init(pci_dev_t dev, struct pci_controller *hose, reg32 |= PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY | PCI_COMMAND_IO; pci_write_config32(dev, PCI_COMMAND, reg32);
/* Use write-combining for the graphics memory, 256MB */base = pci_read_bar32(hose, dev, 2);mtrr_add_request(MTRR_TYPE_WRCOMB, base, 256 << 20);
To make the codes more generic, should we decode the memory size via bar instead of hardcoded 256MB?
mtrr_commit(true);gtt_bar = (void *)pci_read_bar32(pci_bus_to_hose(0), dev, 0); debug("GT bar %p\n", gtt_bar); ret = gma_pm_init_pre_vbios(gtt_bar);--
Regards, Bin