[PATCH] drm/amdgpu: no DC support for headless chips

[Chen, Guchun]

[Public]

For the first two CHIP_HAINAN and CHIP_TOPAZ, using asic_type is fine. But for CHIP_ARCTURUS and CHIP_ALDEBARAN, I wonder if there is any dc hardware harvesting info carried by harvest table in VBIOS. If that's the case, I think we can drop these two, as we can promise it by checking AMD_HARVEST_IP_DMU_MASK in amdgpu_device_has_dc_support.

Regards,
Guchun

-----Original Message-----
From: amd-gfx <amd-gfx-bounces at lists.freedesktop.org> On Behalf Of Alex Deucher
Sent: Friday, December 24, 2021 3:20 AM
To: amd-gfx at lists.freedesktop.org
Cc: Deucher, Alexander <Alexander.Deucher at amd.com>; tarequemd.hanif at yahoo.com
Subject: [PATCH] drm/amdgpu: no DC support for headless chips

Chips with no display hardware should return false for DC support.

Fixes: f7f12b25823c0d ("drm/amdgpu: default to true in amdgpu_device_asic_has_dc_support")
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 9dc86c5a1cad..58e2034984de 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -3166,6 +3166,14 @@ static void amdgpu_device_detect_sriov_bios(struct amdgpu_device *adev)  bool amdgpu_device_asic_has_dc_support(enum amd_asic_type asic_type)  {
 	switch (asic_type) {
+#ifdef CONFIG_DRM_AMDGPU_SI
+	case CHIP_HAINAN:
+#endif
+	case CHIP_TOPAZ:
+	case CHIP_ARCTURUS:
+	case CHIP_ALDEBARAN:
+		/* chips with no display hardware */
+		return false;
 #if defined(CONFIG_DRM_AMD_DC)
 	case CHIP_TAHITI:
 	case CHIP_PITCAIRN:
--
2.33.1