drm/amdgpu: Add kernel parameter support for ignoring bad page threshold

When a GPU hits the bad_page_threshold, it will not be initialized by
the amdgpu driver. This means that the table cannot be cleared, nor can
information gathering be performed (getting serial number, BDF, etc).

If the bad_page_threshold kernel parameter is set to -2,
continue to initialize the GPU, while printing a warning to dmesg that
this action has been done

v2: squash in Luben's fix to restore RAS info reporting

Cc: Luben Tuikov <luben.tuikov@amd.com>
Cc: Mukul Joshi <Mukul.Joshi@amd.com>
Signed-off-by: Kent Russell <kent.russell@amd.com>
Acked-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -205,6 +205,7 @@ extern struct amdgpu_mgpu_info mgpu_info;
 extern int amdgpu_ras_enable;
 extern uint amdgpu_ras_mask;
 extern int amdgpu_bad_page_threshold;
+extern bool amdgpu_ignore_bad_page_threshold;
 extern struct amdgpu_watchdog_timer amdgpu_watchdog_timer;
 extern int amdgpu_async_gfx_ring;
 extern int amdgpu_mcbp;

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

@@ -877,7 +877,7 @@ module_param_named(reset_method, amdgpu_reset_method, int, 0444);
  * result in the GPU entering bad status when the number of total
  * faulty pages by ECC exceeds the threshold value.
  */
-MODULE_PARM_DESC(bad_page_threshold, "Bad page threshold(-1 = auto(default value), 0 = disable bad page retirement)");
+MODULE_PARM_DESC(bad_page_threshold, "Bad page threshold(-1 = auto(default value), 0 = disable bad page retirement, -2 = ignore bad page threshold)");
 module_param_named(bad_page_threshold, amdgpu_bad_page_threshold, int, 0444);
 
 MODULE_PARM_DESC(num_kcq, "number of kernel compute queue user want to setup (8 if set to greater than 8 or less than 0, only affect gfx 8+)");

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

@@ -1105,11 +1105,18 @@ int amdgpu_ras_eeprom_init(struct amdgpu_ras_eeprom_control *control,
 			res = amdgpu_ras_eeprom_correct_header_tag(control,
 								   RAS_TABLE_HDR_VAL);
 		} else {
-			*exceed_err_limit = true;
-			dev_err(adev->dev,
-				"RAS records:%d exceed threshold:%d, "
-				"GPU will not be initialized. Replace this GPU or increase the threshold",
+			dev_err(adev->dev, "RAS records:%d exceed threshold:%d",
 				control->ras_num_recs, ras->bad_page_cnt_threshold);
+			if (amdgpu_bad_page_threshold == -2) {
+				dev_warn(adev->dev, "GPU will be initialized due to bad_page_threshold = -2.");
+				res = 0;
+			} else {
+				*exceed_err_limit = true;
+				dev_err(adev->dev,
+					"RAS records:%d exceed threshold:%d, "
+					"GPU will not be initialized. Replace this GPU or increase the threshold",
+					control->ras_num_recs, ras->bad_page_cnt_threshold);
+			}
 		}
 	} else {
 		DRM_INFO("Creating a new EEPROM table");