drm/i915/gvt: Revert "drm/i915/gvt: Refine the snapshort range of I91…

…5 MCHBAR to optimize gvt-g boot time"

This reverts commit f74a6d9.

BXT needs to access 0x141000-0x1417ff register to obtain the dram info.
But after the snapshot range of I915_MCHBAR is refined in f74a6d9,
it only initializes the range of 0x144000-0x147fff for VGPU and then
causes that the guest GPU can't get the initialized value for dram
detection on BXT.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

drivers/gpu/drm/i915/gvt/handlers.c

@@ -3303,7 +3303,7 @@ void intel_gvt_clean_mmio_info(struct intel_gvt *gvt)
 /* Special MMIO blocks. */
 static struct gvt_mmio_block mmio_blocks[] = {
 	{D_SKL_PLUS, _MMIO(CSR_MMIO_START_RANGE), 0x3000, NULL, NULL},
-	{D_ALL, MCHBAR_MIRROR_REG_BASE, 0x4000, NULL, NULL},
+	{D_ALL, _MMIO(MCHBAR_MIRROR_BASE_SNB), 0x40000, NULL, NULL},
 	{D_ALL, _MMIO(VGT_PVINFO_PAGE), VGT_PVINFO_SIZE,
 		pvinfo_mmio_read, pvinfo_mmio_write},
 	{D_ALL, LGC_PALETTE(PIPE_A, 0), 1024, NULL, NULL},

drivers/gpu/drm/i915/gvt/reg.h

@@ -126,7 +126,4 @@
 #define RING_GFX_MODE(base)	_MMIO((base) + 0x29c)
 #define VF_GUARDBAND		_MMIO(0x83a4)
 
-/* define the effective range of MCHBAR register on Sandybridge+ */
-#define MCHBAR_MIRROR_REG_BASE	_MMIO(MCHBAR_MIRROR_BASE_SNB + 0x4000)
-
 #endif