[PATCH 1/2] drm/amdgpu: Enable scatter gather display support

[Samuel Li]

It's enabled by default. -1 is auto, to allow both vram and gtt
memory be available, for testing purpose only.
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h         | 1 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_display.c | 9 +++++++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c     | 4 ++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c      | 5 +++++
 4 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 292c7e7..6b0ee34 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..dfa11b1 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
@@ -513,8 +513,13 @@ 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) {
+			domain |= AMDGPU_GEM_DOMAIN_GTT;
+		}
+	}
 #endif
 
 	return domain;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index e670936..f0ada24 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..10f1f4f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
@@ -138,6 +138,11 @@ 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_INFO("Scatter gather display: enabled\n");
+	} else if (domain & AMDGPU_GEM_DOMAIN_GTT) {
+		DRM_INFO("Scatter gather display: auto\n");
+	}
 
 	height = ALIGN(mode_cmd->height, 8);
 	size = mode_cmd->pitches[0] * height;
-- 
2.7.4