[PATCH] drm/amdgpu: Add a new module param to disable d3cold

[Ma Jun]

Some platforms can't resume from d3cold state, So add a
new module parameter to disable d3cold state for debugging
purpose or workaround.

Signed-off-by: Ma Jun <Jun.Ma2 at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h        | 1 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 7 +++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c    | 8 ++++++++
 3 files changed, 16 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index a9f54df9d33e..db9f60790267 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -166,6 +166,7 @@ extern char amdgpu_lockup_timeout[AMDGPU_MAX_TIMEOUT_PARAM_LENGTH];
 extern int amdgpu_dpm;
 extern int amdgpu_fw_load_type;
 extern int amdgpu_aspm;
+extern int amdgpu_d3cold;
 extern int amdgpu_runtime_pm;
 extern uint amdgpu_ip_block_mask;
 extern int amdgpu_bapm;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index 22b6a910b7f2..90501c44e7d0 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -264,6 +264,13 @@ bool amdgpu_device_supports_px(struct drm_device *dev)
 bool amdgpu_device_supports_boco(struct drm_device *dev)
 {
 	struct amdgpu_device *adev = drm_to_adev(dev);
+	struct pci_dev *parent;
+
+	if (!amdgpu_d3cold) {
+		parent = pcie_find_root_port(adev->pdev);
+		pci_d3cold_disable(parent);
+		return false;
+	}
 
 	if (adev->has_pr3 ||
 	    ((adev->flags & AMD_IS_PX) && amdgpu_is_atpx_hybrid()))
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index 5f14f04cb553..c9fbb8bd4169 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -145,6 +145,7 @@ char amdgpu_lockup_timeout[AMDGPU_MAX_TIMEOUT_PARAM_LENGTH];
 int amdgpu_dpm = -1;
 int amdgpu_fw_load_type = -1;
 int amdgpu_aspm = -1;
+int amdgpu_d3cold = -1;
 int amdgpu_runtime_pm = -1;
 uint amdgpu_ip_block_mask = 0xffffffff;
 int amdgpu_bapm = -1;
@@ -359,6 +360,13 @@ module_param_named(fw_load_type, amdgpu_fw_load_type, int, 0444);
 MODULE_PARM_DESC(aspm, "ASPM support (1 = enable, 0 = disable, -1 = auto)");
 module_param_named(aspm, amdgpu_aspm, int, 0444);
 
+/**
+ * DOC: d3cold (int)
+ * To disable d3cold (1 = enable, 0 = disable). The default is -1 (auto, enabled).
+ */
+MODULE_PARM_DESC(d3cold, "d3cold support (1 = enable, 0 = disable, -1 = auto)");
+module_param_named(d3cold, amdgpu_d3cold, int, 0444);
+
 /**
  * DOC: runpm (int)
  * Override for runtime power management control for dGPUs. The amdgpu driver can dynamically power down
-- 
2.34.1