drm/amdgpu: use the callback function for reset status polling on IMU

Switch to use the callback function to poll the reset status on IMU.
Because it will have different sequency on other ASICs.

v2: drop unused variable (Alex)

Acked-by: Alex Deucher <[e-mail]>
Signed-off-by: Huang Rui <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
     void (*setup_imu)(struct amdgpu_device *adev);
     int (*start_imu)(struct amdgpu_device *adev);
     void (*program_rlc_ram)(struct amdgpu_device *adev);
+    int (*wait_for_reset_status)(struct amdgpu_device *adev);
 };
 
 struct imu_rlc_ram_golden {

drivers/gpu/drm/amd/amdgpu/imu_v11_0.c

···
 	return 0;
 }
 
+static int imu_v11_0_wait_for_reset_status(struct amdgpu_device *adev)
+{
+	int i, imu_reg_val = 0;
+
+	for (i = 0; i < adev->usec_timeout; i++) {
+		imu_reg_val = RREG32_SOC15(GC, 0, regGFX_IMU_GFX_RESET_CTRL);
+		if ((imu_reg_val & 0x1f) == 0x1f)
+			break;
+		udelay(1);
+	}
+
+	if (i >= adev->usec_timeout) {
+		dev_err(adev->dev, "init imu: IMU start timeout\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
 static void imu_v11_0_setup(struct amdgpu_device *adev)
 {
 	int imu_reg_val;
···
 
 static int imu_v11_0_start(struct amdgpu_device *adev)
 {
-	int imu_reg_val, i;
+	int imu_reg_val;
 
 	//Start IMU by set GFX_IMU_CORE_CTRL.CRESET = 0
 	imu_reg_val = RREG32_SOC15(GC, 0, regGFX_IMU_CORE_CTRL);
 	imu_reg_val &= 0xfffffffe;
 	WREG32_SOC15(GC, 0, regGFX_IMU_CORE_CTRL, imu_reg_val);
 
-	if (adev->gfx.imu.mode == DEBUG_MODE) {
-		for (i = 0; i < adev->usec_timeout; i++) {
-			imu_reg_val = RREG32_SOC15(GC, 0, regGFX_IMU_GFX_RESET_CTRL);
-			if ((imu_reg_val & 0x1f) == 0x1f)
-				break;
-			udelay(1);
-		}
-
-		if (i >= adev->usec_timeout) {
-			dev_err(adev->dev, "init imu: IMU start timeout\n");
-			return -ETIMEDOUT;
-		}
-	}
+	if (adev->gfx.imu.mode == DEBUG_MODE)
+		return imu_v11_0_wait_for_reset_status(adev);
 
 	return 0;
 }
···
 	.setup_imu = imu_v11_0_setup,
 	.start_imu = imu_v11_0_start,
 	.program_rlc_ram = imu_v11_0_program_rlc_ram,
+	.wait_for_reset_status = imu_v11_0_wait_for_reset_status,
 };