nb/intel/ironlake: Simplify GMA SSDT generator

Simplify generation of GMA SSDT, using updated naming convention.
If acpi_fill_ssdt is being invoked, then we know the IGD device is
present and enabled, so we can skip those checks. And the SSDT
generator now checks that the gfx struct is populated, so we can
skip that too.

Change-Id: I1b6d57c091441aa7431061b1f16135d54cc97b47
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39950
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/northbridge/intel/ironlake/gma.c b/src/northbridge/intel/ironlake/gma.c
index b35305b..6dbc156 100644
--- a/src/northbridge/intel/ironlake/gma.c
+++ b/src/northbridge/intel/ironlake/gma.c
@@ -214,25 +214,11 @@
 	res->size = (resource_t) 0x10000000;
 }
 
-const struct i915_gpu_controller_info *
-intel_gma_get_controller_info(void)
+static void gma_generate_ssdt(struct device *device)
 {
-	struct device *dev = pcidev_on_root(0x2, 0);
-	if (!dev) {
-		return NULL;
-	}
-	struct northbridge_intel_ironlake_config *chip = dev->chip_info;
-	return &chip->gfx;
-}
+	const struct northbridge_intel_ironlake_config *chip = device->chip_info;
 
-static void gma_ssdt(struct device *device)
-{
-	const struct i915_gpu_controller_info *gfx = intel_gma_get_controller_info();
-	if (!gfx) {
-		return;
-	}
-
-	drivers_intel_gma_displays_ssdt_generate(gfx);
+	drivers_intel_gma_displays_ssdt_generate(&chip->gfx);
 }
 
 static unsigned long
@@ -266,14 +252,14 @@
 };
 
 static struct device_operations gma_func0_ops = {
-	.read_resources = gma_read_resources,
-	.set_resources = pci_dev_set_resources,
-	.enable_resources = pci_dev_enable_resources,
-	.acpi_fill_ssdt = gma_ssdt,
-	.init = gma_func0_init,
-	.scan_bus = 0,
-	.enable = 0,
-	.ops_pci = &gma_pci_ops,
+	.read_resources		= gma_read_resources,
+	.set_resources		= pci_dev_set_resources,
+	.enable_resources	= pci_dev_enable_resources,
+	.acpi_fill_ssdt		= gma_generate_ssdt,
+	.init			= gma_func0_init,
+	.scan_bus		= 0,
+	.enable			= 0,
+	.ops_pci		= &gma_pci_ops,
 	.write_acpi_tables	= gma_write_acpi_tables,
 };