From 6ba5b613837c5d997ad8297b22fc46cd0be58d76 Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Thu, 9 Nov 2023 15:31:00 -0500 Subject: drm/amdgpu: add a module parameter to control the AGP aperture MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a module parameter to control the AGP aperture. The AGP aperture is an aperture in the GPU's internal address space which provides direct non-paged access to the platform address space. This access is non-snooped so only uncached memory can be accessed. Add a knob so that we can toggle this for debugging. Fixes: 67318cb84341 ("drm/amdgpu/gmc11: set gart placement GC11") Acked-by: Christian König Reviewed-by: Mario Limonciello Tested-by: Mario Limonciello # PHX & Navi33 Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index 3095a3a864af..8f24cabe2155 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -207,6 +207,7 @@ int amdgpu_user_partt_mode = AMDGPU_AUTO_COMPUTE_PARTITION_MODE; int amdgpu_umsch_mm; int amdgpu_seamless = -1; /* auto */ uint amdgpu_debug_mask; +int amdgpu_agp = -1; /* auto */ static void amdgpu_drv_delayed_reset_work_handler(struct work_struct *work); @@ -961,6 +962,15 @@ module_param_named(seamless, amdgpu_seamless, int, 0444); MODULE_PARM_DESC(debug_mask, "debug options for amdgpu, disabled by default"); module_param_named(debug_mask, amdgpu_debug_mask, uint, 0444); +/** + * DOC: agp (int) + * Enable the AGP aperture. This provides an aperture in the GPU's internal + * address space for direct access to system memory. Note that these accesses + * are non-snooped, so they are only used for access to uncached memory. + */ +MODULE_PARM_DESC(agp, "AGP (-1 = auto (default), 0 = disable, 1 = enable)"); +module_param_named(agp, amdgpu_agp, int, 0444); + /* These devices are not supported by amdgpu. * They are supported by the mach64, r128, radeon drivers */ -- cgit v1.2.3