drm/amd/pm: avoid duplicate powergate/ungate setting

Just bail out if the target IP block is already in the desired
powergate/ungate state. This can avoid some duplicate settings
which sometimes may cause unexpected issues.

Link: https://lore.kernel.org/all/[e-mail]/
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=214921
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=215025
Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1789
Fixes: bf756fb833cb ("drm/amdgpu: add missing cleanups for Polaris12 UVD/VCE on suspend")
Signed-off-by: Evan Quan <[e-mail]>
Tested-by: Borislav Petkov <[e-mail]>
Reviewed-by: Lijo Lazar <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>
Cc: [e-mail]

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

···
 		adev->rmmio_size = pci_resource_len(adev->pdev, 2);
 	}
 
+	for (i = 0; i < AMD_IP_BLOCK_TYPE_NUM; i++)
+		atomic_set(&adev->pm.pwr_state[i], POWER_STATE_UNKNOWN);
+
 	adev->rmmio = ioremap(adev->rmmio_base, adev->rmmio_size);
 	if (adev->rmmio == NULL) {
 		return -ENOMEM;

drivers/gpu/drm/amd/include/amd_shared.h

···
 	AMD_IP_BLOCK_TYPE_ACP,
 	AMD_IP_BLOCK_TYPE_VCN,
 	AMD_IP_BLOCK_TYPE_MES,
-	AMD_IP_BLOCK_TYPE_JPEG
+	AMD_IP_BLOCK_TYPE_JPEG,
+	AMD_IP_BLOCK_TYPE_NUM,
 };
 
 enum amd_clockgating_state {

drivers/gpu/drm/amd/pm/amdgpu_dpm.c

···
 {
 	int ret = 0;
 	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
+	enum ip_power_state pwr_state = gate ? POWER_STATE_OFF : POWER_STATE_ON;
+
+	if (atomic_read(&adev->pm.pwr_state[block_type]) == pwr_state) {
+		dev_dbg(adev->dev, "IP block%d already in the target %s state!",
+				block_type, gate ? "gate" : "ungate");
+		return 0;
+	}
 
 	switch (block_type) {
 	case AMD_IP_BLOCK_TYPE_UVD:
···
 	default:
 		break;
 	}
+
+	if (!ret)
+		atomic_set(&adev->pm.pwr_state[block_type], pwr_state);
 
 	return ret;
 }

drivers/gpu/drm/amd/pm/inc/amdgpu_dpm.h

···
 	enum amd_dpm_forced_level forced_level;
 };
 
+enum ip_power_state {
+	POWER_STATE_UNKNOWN,
+	POWER_STATE_ON,
+	POWER_STATE_OFF,
+};
+
 struct amdgpu_pm {
 	struct mutex		mutex;
 	u32                     current_sclk;
···
 	struct i2c_adapter smu_i2c;
 	struct mutex		smu_i2c_mutex;
 	struct list_head	pm_attr_list;
+
+	atomic_t		pwr_state[AMD_IP_BLOCK_TYPE_NUM];
 };
 
 #define R600_SSTU_DFLT                               0