[PATCH v2 1/1] drm/amdgpu: Enable scatter gather display support

Samuel Li
2018-03-27T22:22:51Z

It's auto by default. For CZ/ST, auto setting enables sg display
when vram size is small; otherwise still uses vram.
This patch fixed some potential hang issue introduced by change
"allow framebuffer in GART memory as well" due to CZ/ST hardware
limitation.

v2: Change default setting to auto, also some misc changes.
Signed-off-by: Samuel Li <Samuel.Li@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 +
drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 10 ++++++++--
drivers/gpu/drm/amd/amdgpu/amdgpu_display.h | 2 ++
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 ++++
drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c | 2 ++
drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++-
6 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index a7e2229..c942362 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -129,6 +129,7 @@ extern int amdgpu_lbpw;
extern int amdgpu_compute_multipipe;
extern int amdgpu_gpu_recovery;
extern int amdgpu_emu_mode;
+extern int amdgpu_sg_display;

#ifdef CONFIG_DRM_AMDGPU_SI
extern int amdgpu_si_support;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
index 5495b29..1e7b950 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -513,8 +513,14 @@ uint32_t amdgpu_display_framebuffer_domains(struct amdgpu_device *adev)
#if defined(CONFIG_DRM_AMD_DC)
if (adev->asic_type >= CHIP_CARRIZO && adev->asic_type < CHIP_RAVEN &&
adev->flags & AMD_IS_APU &&
- amdgpu_device_asic_has_dc_support(adev->asic_type))
- domain |= AMDGPU_GEM_DOMAIN_GTT;
+ amdgpu_device_asic_has_dc_support(adev->asic_type)) {
+ if (amdgpu_sg_display == 1)
+ domain = AMDGPU_GEM_DOMAIN_GTT;
+ else if (amdgpu_sg_display == -1) {
+ if (adev->gmc.real_vram_size < AMDGPU_SG_THRESHOLD)
+ domain = AMDGPU_GEM_DOMAIN_GTT;
+ }
+ }
#endif

return domain;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h
index 2b11d80..2b25393 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h
@@ -23,6 +23,8 @@
#ifndef __AMDGPU_DISPLAY_H__
#define __AMDGPU_DISPLAY_H__

+#define AMDGPU_SG_THRESHOLD (256*1024*1024)
+
uint32_t amdgpu_display_framebuffer_domains(struct amdgpu_device *adev);
struct drm_framebuffer *
amdgpu_display_user_framebuffer_create(struct drm_device *dev,
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 1bfce79..19f11a5 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -132,6 +132,7 @@ int amdgpu_lbpw = -1;
int amdgpu_compute_multipipe = -1;
int amdgpu_gpu_recovery = -1; /* auto */
int amdgpu_emu_mode = 0;
+int amdgpu_sg_display = -1;

MODULE_PARM_DESC(vramlimit, "Restrict VRAM for testing, in megabytes");
module_param_named(vramlimit, amdgpu_vram_limit, int, 0600);
@@ -290,6 +291,9 @@ module_param_named(gpu_recovery, amdgpu_gpu_recovery, int, 0444);
MODULE_PARM_DESC(emu_mode, "Emulation mode, (1 = enable, 0 = disable)");
module_param_named(emu_mode, amdgpu_emu_mode, int, 0444);

+MODULE_PARM_DESC(sg_display, "Enable scatter gather display, (1 = enable, 0 = disable, -1 = auto");
+module_param_named(sg_display, amdgpu_sg_display, int, 0444);
+
#ifdef CONFIG_DRM_AMDGPU_SI

#if defined(CONFIG_DRM_RADEON) || defined(CONFIG_DRM_RADEON_MODULE)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
index 1206301..f57c355 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
@@ -138,6 +138,8 @@ static int amdgpufb_create_pinned_object(struct amdgpu_fbdev *rfbdev,
mode_cmd->pitches[0] = amdgpu_align_pitch(adev, mode_cmd->width, cpp,
fb_tiled);
domain = amdgpu_display_framebuffer_domains(adev);
+ if (domain & AMDGPU_GEM_DOMAIN_GTT)
+ DRM_DEBUG_DRIVER("Scatter gather display: enabled\n");

height = ALIGN(mode_cmd->height, 8);
size = mode_cmd->pitches[0] * height;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 68ab325..7e9f247 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -3074,7 +3074,8 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
domain = AMDGPU_GEM_DOMAIN_VRAM;

r = amdgpu_bo_pin(rbo, domain, &afb->address);
-
+ rbo->preferred_domains = domain;
+ rbo->allowed_domains = domain;
amdgpu_bo_unreserve(rbo);

if (unlikely(r != 0)) {
--
2.7.4