Hi Bin,
On 3 January 2015 at 20:18, Bin Meng bmeng.cn@gmail.com wrote:
Hi Simon,
On Fri, Jan 2, 2015 at 7:18 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
Changes in v2:
- Remove definition of 'ulong start' from this patch
arch/x86/cpu/ivybridge/gma.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/arch/x86/cpu/ivybridge/gma.c b/arch/x86/cpu/ivybridge/gma.c index cf4f87c..6cf9654 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> @@ -735,6 +736,7 @@ int gma_func0_init(pci_dev_t dev, struct pci_controller *hose, ulong start; #endif void *gtt_bar;
ulong base; u32 reg32; int ret;@@ -743,6 +745,11 @@ 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);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);--
Do you have any comments regarding to what I said in http://lists.denx.de/pipermail/u-boot/2014-December/199955.html?
Ah yes I meant to say that I did look at a function to return the BAR size, but it involves changing the BAR. I have a patch out to convert PCI to driver model and there we will be able to store the size. So perhaps we should revisit this later?
Regards, Simon