x86/early-quirks: export the stolen region as a resource

We duplicate the stolen discovery code in early-quirks and in i915,
however if we just export the region as a resource from early-quirks we
can nuke the duplication.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171211151822.20953-3-matthew.auld@intel.com

arch/x86/kernel/early-quirks.c

@@ -532,6 +532,9 @@ static const struct pci_device_id intel_early_ids[] __initconst = {
 	INTEL_CNL_IDS(&gen9_early_ops),
 };
 
+struct resource intel_graphics_stolen_res __ro_after_init = DEFINE_RES_MEM(0, 0);
+EXPORT_SYMBOL(intel_graphics_stolen_res);
+
 static void __init
 intel_graphics_stolen(int num, int slot, int func,
 		      const struct intel_early_ops *early_ops)
@@ -546,8 +549,12 @@ intel_graphics_stolen(int num, int slot, int func,
 		return;
 
 	end = base + size - 1;
-	printk(KERN_INFO "Reserving Intel graphics memory at %pa-%pa\n",
-	       &base, &end);
+
+	intel_graphics_stolen_res.start = base;
+	intel_graphics_stolen_res.end = end;
+
+	printk(KERN_INFO "Reserving Intel graphics memory at %pR\n",
+	       &intel_graphics_stolen_res);
 
 	/* Mark this space as reserved */
 	e820__range_add(base, size, E820_TYPE_RESERVED);

include/drm/i915_drm.h

@@ -36,6 +36,9 @@ extern bool i915_gpu_lower(void);
 extern bool i915_gpu_busy(void);
 extern bool i915_gpu_turbo_disable(void);
 
+/* Exported from arch/x86/kernel/early-quirks.c */
+extern struct resource intel_graphics_stolen_res;
+
 /*
  * The Bridge device's PCI config space has information about the
  * fb aperture size and the amount of pre-reserved memory.