drm/i915/bdw: support GMS and GGMS changes

All the BARs have the ability to grow.

v2: Pulled out the simulator workaround to a separate patch.
Rebased.

v3: Rebase onto latest vlv patches from Jesse.

v4: Rebased on top of the early stolen quirk patch from Jesse.

v5: Use the new macro names.
s/INTEL_BDW_PCI_IDS_D/INTEL_BDW_D_IDS
s/INTEL_BDW_PCI_IDS_M/INTEL_BDW_M_IDS
It's Jesse's fault for not following the convention I originally set.

Cc: Ingo Molnar <[e-mail]>
Cc: H. Peter Anvin <[e-mail]>
Cc: Jesse Barnes <[e-mail]>
Signed-off-by: Ben Widawsky <[e-mail]>
Signed-off-by: Daniel Vetter <[e-mail]>

arch/x86/kernel/early-quirks.c

···
 	return gmch_ctrl << 25; /* 32 MB units */
 }
 
+static inline size_t gen8_stolen_size(int num, int slot, int func)
+{
+	u16 gmch_ctrl;
+
+	gmch_ctrl = read_pci_config_16(num, slot, func, SNB_GMCH_CTRL);
+	gmch_ctrl >>= BDW_GMCH_GMS_SHIFT;
+	gmch_ctrl &= BDW_GMCH_GMS_MASK;
+	return gmch_ctrl << 25; /* 32 MB units */
+}
+
 typedef size_t (*stolen_size_fn)(int num, int slot, int func);
 
 static struct pci_device_id intel_stolen_ids[] __initdata = {
···
 	INTEL_IVB_D_IDS(gen6_stolen_size),
 	INTEL_HSW_D_IDS(gen6_stolen_size),
 	INTEL_HSW_M_IDS(gen6_stolen_size),
+	INTEL_BDW_M_IDS(gen8_stolen_size),
+	INTEL_BDW_D_IDS(gen8_stolen_size)
 };
 
 static void __init intel_graphics_stolen(int num, int slot, int func)

drivers/gpu/drm/i915/i915_gem_gtt.c

···
 	return snb_gmch_ctl << 20;
 }
 
+static inline unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl)
+{
+	bdw_gmch_ctl >>= BDW_GMCH_GGMS_SHIFT;
+	bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK;
+	if (bdw_gmch_ctl)
+		bdw_gmch_ctl = 1 << bdw_gmch_ctl;
+	return bdw_gmch_ctl << 20;
+}
+
 static inline size_t gen6_get_stolen_size(u16 snb_gmch_ctl)
 {
 	snb_gmch_ctl >>= SNB_GMCH_GMS_SHIFT;
 	snb_gmch_ctl &= SNB_GMCH_GMS_MASK;
 	return snb_gmch_ctl << 25; /* 32 MB units */
+}
+
+static inline size_t gen8_get_stolen_size(u16 bdw_gmch_ctl)
+{
+	bdw_gmch_ctl >>= BDW_GMCH_GMS_SHIFT;
+	bdw_gmch_ctl &= BDW_GMCH_GMS_MASK;
+	return bdw_gmch_ctl << 25; /* 32 MB units */
 }
 
 static int gen6_gmch_probe(struct drm_device *dev,
···
 	if (!pci_set_dma_mask(dev->pdev, DMA_BIT_MASK(40)))
 		pci_set_consistent_dma_mask(dev->pdev, DMA_BIT_MASK(40));
 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
-	gtt_size = gen6_get_total_gtt_size(snb_gmch_ctl);
 
-	*stolen = gen6_get_stolen_size(snb_gmch_ctl);
-	*gtt_total = (gtt_size / sizeof(gen6_gtt_pte_t)) << PAGE_SHIFT;
+	if (IS_GEN8(dev)) {
+		gtt_size = gen8_get_total_gtt_size(snb_gmch_ctl);
+		*gtt_total = (gtt_size / 8) << PAGE_SHIFT;
+		*stolen = gen8_get_stolen_size(snb_gmch_ctl);
+	} else {
+		gtt_size = gen6_get_total_gtt_size(snb_gmch_ctl);
+		*gtt_total = (gtt_size / sizeof(gen6_gtt_pte_t)) << PAGE_SHIFT;
+		*stolen = gen6_get_stolen_size(snb_gmch_ctl);
+	}
 
 	/* For Modern GENs the PTEs and register space are split in the BAR */
 	gtt_bus_addr = pci_resource_start(dev->pdev, 0) +
···
 	if (!dev_priv->gtt.gsm) {
 		DRM_ERROR("Failed to map the gtt page table\n");
 		return -ENOMEM;
+
 	}
 
 	ret = setup_scratch_page(dev);

include/drm/i915_drm.h

···
 #define    SNB_GMCH_GGMS_MASK	0x3
 #define    SNB_GMCH_GMS_SHIFT   3 /* Graphics Mode Select */
 #define    SNB_GMCH_GMS_MASK    0x1f
+#define    BDW_GMCH_GGMS_SHIFT	6
+#define    BDW_GMCH_GGMS_MASK	0x3
+#define    BDW_GMCH_GMS_SHIFT   8
+#define    BDW_GMCH_GMS_MASK    0xff
 
 #define I830_GMCH_CTRL			0x52