From a0a53aa8c7b491a43e2ef66786f9511bae8cbc35 Mon Sep 17 00:00:00 2001 From: Samuel Li Date: Mon, 8 Apr 2013 17:25:47 -0400 Subject: drm/radeon: Use direct mapping for fast fb access on RS690 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch allows the CPU to map the stolen vram segment directly rather than going through the PCI BAR. This significantly improves performance for certain workloads with a properly patched ddx. Use radeon.fastfb=1 to enable it (disabled by default). Currently only supported on RS690, but support for RS780/880 and newer APUs may be added eventually. Signed-off-by: Samuel Li Reviewed-by: Christian König Signed-off-by: Alex Deucher --- drivers/gpu/drm/radeon/rs690.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'drivers/gpu/drm/radeon/rs690.c') diff --git a/drivers/gpu/drm/radeon/rs690.c b/drivers/gpu/drm/radeon/rs690.c index 5706d2ac75ab..ab4c86cfd552 100644 --- a/drivers/gpu/drm/radeon/rs690.c +++ b/drivers/gpu/drm/radeon/rs690.c @@ -148,6 +148,8 @@ void rs690_pm_info(struct radeon_device *rdev) static void rs690_mc_init(struct radeon_device *rdev) { u64 base; + uint32_t h_addr, l_addr; + unsigned long long k8_addr; rs400_gart_adjust_size(rdev); rdev->mc.vram_is_ddr = true; @@ -160,6 +162,27 @@ static void rs690_mc_init(struct radeon_device *rdev) base = RREG32_MC(R_000100_MCCFG_FB_LOCATION); base = G_000100_MC_FB_START(base) << 16; rdev->mc.igp_sideport_enabled = radeon_atombios_sideport_present(rdev); + + /* Use K8 direct mapping for fast fb access. */ + rdev->fastfb_working = false; + h_addr = G_00005F_K8_ADDR_EXT(RREG32_MC(R_00005F_MC_MISC_UMA_CNTL)); + l_addr = RREG32_MC(R_00001E_K8_FB_LOCATION); + k8_addr = ((unsigned long long)h_addr) << 32 | l_addr; +#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_PAE) + if (k8_addr + rdev->mc.visible_vram_size < 0x100000000ULL) +#endif + { + /* FastFB shall be used with UMA memory. Here it is simply disabled when sideport + * memory is present. + */ + if (rdev->mc.igp_sideport_enabled == false && radeon_fastfb == 1) { + DRM_INFO("Direct mapping: aper base at 0x%llx, replaced by direct mapping base 0x%llx.\n", + (unsigned long long)rdev->mc.aper_base, k8_addr); + rdev->mc.aper_base = (resource_size_t)k8_addr; + rdev->fastfb_working = true; + } + } + rs690_pm_info(rdev); radeon_vram_location(rdev, &rdev->mc, base); rdev->mc.gtt_base_align = rdev->mc.gtt_size - 1; -- cgit v1.2.3