drm/amdgpu: add asic callback to get memsize register

Newer asics use different registers so abstract it.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -751,6 +751,11 @@ static int vi_asic_reset(struct amdgpu_device *adev)
 	return r;
 }
 
+static u32 vi_get_config_memsize(struct amdgpu_device *adev)
+{
+	return RREG32(mmCONFIG_MEMSIZE);
+}
+
 static int vi_set_uvd_clock(struct amdgpu_device *adev, u32 clock,
 			u32 cntl_reg, u32 status_reg)
 {
@@ -900,6 +905,7 @@ static const struct amdgpu_asic_funcs vi_asic_funcs =
 	.get_xclk = &vi_get_xclk,
 	.set_uvd_clocks = &vi_set_uvd_clocks,
 	.set_vce_clocks = &vi_set_vce_clocks,
+	.get_config_memsize = &vi_get_config_memsize,
 };
 
 static int vi_common_early_init(void *handle)