drm/amdgpu: enable lbpw on raven

Signed-off-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -111,6 +111,7 @@ extern int amdgpu_pos_buf_per_se;
 extern int amdgpu_cntl_sb_buf_per_se;
 extern int amdgpu_param_buf_per_se;
 extern int amdgpu_job_hang_limit;
+extern int amdgpu_lbpw;
 
 #define AMDGPU_DEFAULT_GTT_SIZE_MB		3072ULL /* 3GB by default */
 #define AMDGPU_WAIT_IDLE_TIMEOUT_IN_MS	        3000

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

@@ -113,6 +113,7 @@ int amdgpu_pos_buf_per_se = 0;
 int amdgpu_cntl_sb_buf_per_se = 0;
 int amdgpu_param_buf_per_se = 0;
 int amdgpu_job_hang_limit = 0;
+int amdgpu_lbpw = -1;
 
 MODULE_PARM_DESC(vramlimit, "Restrict VRAM for testing, in megabytes");
 module_param_named(vramlimit, amdgpu_vram_limit, int, 0600);
@@ -238,6 +239,8 @@ module_param_named(param_buf_per_se, amdgpu_param_buf_per_se, int, 0444);
 MODULE_PARM_DESC(job_hang_limit, "how much time allow a job hang and not drop it (default 0)");
 module_param_named(job_hang_limit, amdgpu_job_hang_limit, int ,0444);
 
+MODULE_PARM_DESC(lbpw, "Load Balancing Per Watt (LBPW) support (1 = enable, 0 = disable, -1 = auto)");
+module_param_named(lbpw, amdgpu_lbpw, int, 0444);
 
 static const struct pci_device_id pciidlist[] = {
 #ifdef  CONFIG_DRM_AMDGPU_SI

drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c

@@ -683,6 +683,18 @@ static void gfx_v9_0_init_lbpw(struct amdgpu_device *adev)
 	mutex_unlock(&adev->grbm_idx_mutex);
 }
 
+static void gfx_v9_0_enable_lbpw(struct amdgpu_device *adev, bool enable)
+{
+        uint32_t data = 0;
+
+        data = RREG32_SOC15(GC, 0, mmRLC_LB_CNTL);
+        if (enable)
+                data |= RLC_LB_CNTL__LOAD_BALANCE_ENABLE_MASK;
+        else
+                data &= ~RLC_LB_CNTL__LOAD_BALANCE_ENABLE_MASK;
+        WREG32_SOC15(GC, 0, mmRLC_LB_CNTL, data);
+}
+
 static void rv_init_cp_jump_table(struct amdgpu_device *adev)
 {
 	const __le32 *fw_data;
@@ -2229,6 +2241,13 @@ static int gfx_v9_0_rlc_resume(struct amdgpu_device *adev)
 			return r;
 	}
 
+	if (adev->asic_type == CHIP_RAVEN) {
+		if (amdgpu_lbpw != 0)
+			gfx_v9_0_enable_lbpw(adev, true);
+		else
+			gfx_v9_0_enable_lbpw(adev, false);
+	}
+
 	gfx_v9_0_rlc_start(adev);
 
 	return 0;