drivers/intel/gma: Hook up libgfxinit in romstage

A mainboard port needs to:

- select `CONFIG_MAINBOARD_HAS_EARLY_LIBGFXINIT'

- implement the Ada package `GMA.Mainboard' with a single function
  `ports' that returns a list of ports to be probed for displays.

- set the desired `GFX_GMA_DEFAULT_MMIO' IO memory address to use
  in romstage (and ramstage) for the graphic device.

BUG=b:252792591
BRANCH=firmware-brya-14505.B
TEST=libgfxinit compiles in romstage.
     libgfxinit successfully executes in romstage and ramstage using
     the requested MMIO setting on skolas.

Change-Id: I3c2101de10dc5df54fe873e43bbe0f1c4dccff44
Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70276
Reviewed-by: Tarun Tuli <taruntuli@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/arch/x86/car.ld

@@ -72,6 +72,13 @@
 	 * runtime. Therefore, they can be placed in the _bss region. */
 #if CONFIG(ROMSTAGE_LIBHWBASE)
 	*(.data.hw__*_E)
+#endif
+#if CONFIG(EARLY_GFX_GMA)
+	*(.data.gma*_E)
+	/* libgfxinit uses a boolean variable to track its initialization
+	 * state. Since the initial value is False it can safely be placed in
+	 * the _bss region. */
+	*(.data.hw__gfx__gma__initialized)
 #endif
 	. = ALIGN(ARCH_POINTER_ALIGN_SIZE);
 	_ebss = .;

src/device/Kconfig

@@ -4,7 +4,7 @@ menu "Devices"
 
 config HAVE_VGA_TEXT_FRAMEBUFFER
 	bool
-	depends on !NO_GFX_INIT
+	depends on !(NO_GFX_INIT && NO_EARLY_GFX_INIT)
 	help
 	  Selected by graphics drivers that support legacy VGA text mode.
 
@@ -58,6 +58,13 @@ config MAINBOARD_HAS_LIBGFXINIT
 	  Selected by mainboards that implement support for `libgfxinit`.
 	  Usually this requires a list of ports to be probed for displays.
 
+config MAINBOARD_HAS_EARLY_LIBGFXINIT
+	def_bool n
+	help
+	  Selected by mainboards that implement early (cache-as-ram
+	  stage) support of `libgfxinit`. Usually this requires a list
+	  of ports to be probed for displays.
+
 choice
 	prompt "Graphics initialization"
 	default NO_GFX_INIT if VGA_ROM_RUN_DEFAULT && PAYLOAD_SEABIOS
@@ -117,6 +124,28 @@ config NO_GFX_INIT
 
 endchoice
 
+choice
+	prompt "Early (romstage) graphics initialization"
+	default MAINBOARD_USE_EARLY_LIBGFXINIT if MAINBOARD_HAS_EARLY_LIBGFXINIT
+	default NO_EARLY_GFX_INIT
+
+config NO_EARLY_GFX_INIT
+	bool "None"
+	help
+	  Select this to not perform any graphics initialization at
+	  romstage.
+
+config MAINBOARD_USE_EARLY_LIBGFXINIT
+	bool "Use libgfxinit"
+	depends on MAINBOARD_HAS_EARLY_LIBGFXINIT
+	select ROMSTAGE_VGA
+	help
+	  Use the SPARK library `libgfxinit` for the romstage native
+	  graphics initialization. This requires an Ada
+	  toolchain. Graphics at romstage is limited to VGA text mode.
+
+endchoice
+
 config PRE_GRAPHICS_DELAY_MS
 	int "Graphics initialization delay in ms"
 	default 0

src/drivers/intel/gma/Kconfig

@@ -90,15 +90,31 @@ config GFX_GMA
 	depends on MAINBOARD_USE_LIBGFXINIT || INTEL_GMA_LIBGFXINIT_EDID
 	select RAMSTAGE_LIBHWBASE
 
+config EARLY_GFX_GMA
+	def_bool y
+	depends on SOC_INTEL_ALDERLAKE
+	depends on MAINBOARD_USE_EARLY_LIBGFXINIT
+	select ROMSTAGE_LIBHWBASE
+
+config GFX_GMA_DEFAULT_MMIO
+	hex
+	depends on HWBASE_STATIC_MMIO && (GFX_GMA || EARLY_GFX_GMA)
+	help
+	  Graphics device MMIO address. This is typically an unused
+	  memory mapping region which can be allocated to the MMIO
+	  region as graphics PCI device Base Address Range zero.
+
 config GFX_GMA_PANEL_1_ON_EDP
 	bool
-	depends on GFX_GMA || MAINBOARD_HAS_LIBGFXINIT
+	depends on GFX_GMA || MAINBOARD_HAS_LIBGFXINIT \
+		|| MAINBOARD_HAS_EARLY_LIBGFXINIT
 	default n if GFX_GMA_PANEL_1_ON_LVDS
 	default y
 
 config GFX_GMA_PANEL_1_ON_LVDS
 	bool
-	depends on GFX_GMA || MAINBOARD_HAS_LIBGFXINIT
+	depends on GFX_GMA || MAINBOARD_HAS_LIBGFXINIT \
+		|| MAINBOARD_HAS_EARLY_LIBGFXINIT
 	default y if NORTHBRIDGE_INTEL_GM45 || NORTHBRIDGE_INTEL_IRONLAKE
 	default n
 
@@ -111,7 +127,7 @@ config INTEL_GMA_OPREGION_2_1
 	bool
 	default n
 
-if GFX_GMA
+if GFX_GMA || EARLY_GFX_GMA
 
 config GFX_GMA_DYN_CPU
 	def_bool y

src/drivers/intel/gma/Makefile.inc

@@ -20,24 +20,39 @@ endif
 
 $(call add_vbt_to_cbfs, vbt.bin, $(call strip_quotes,$(CONFIG_INTEL_GMA_VBT_FILE)))
 
-ifeq ($(CONFIG_GFX_GMA),y)
+ifneq (,$(filter y, $(CONFIG_GFX_GMA) $(CONFIG_EARLY_GFX_GMA)))
+
+gfx-gma-stages = \
+	$(if $(filter y,$(CONFIG_EARLY_GFX_GMA)),romstage) \
+	$(if $(filter y,$(CONFIG_GFX_GMA)),ramstage) \
 
 $(call add-special-class,gfxinit)
-gfxinit-handler = $(eval ramstage-srcs += $(1)$(2))
+gfxinit-handler +=$(foreach stage, $(gfx-gma-stages), \
+	$(eval $(stage)-srcs += $$(addprefix $(1),$(2))))
 
 $(call add-special-class,gfxinit-gen)
-gfxinit-gen-handler = \
+gfxinit-gen-handler += \
 	$(eval additional-dirs += $(dir $(2))) \
-	$(eval ramstage-srcs += $(2)) \
+	$(foreach stage, $(gfx-gma-stages), \
-	$(eval ramstage-ads-deps += $(2)) \
+		$(eval $(stage)-srcs += $(2)) \
-	$(eval ramstage-adb-deps += $(2)) \
+		$(eval $(stage)-ads-deps += $(2)) \
+		$(eval $(stage)-adb-deps += $(2))) \
 	$(eval $(2): $(obj)/config.h)
 
+ifeq ($(CONFIG_GFX_GMA_DEFAULT_MMIO),)
 CONFIG_GFX_GMA_DEFAULT_MMIO := 0 # dummy, will be overwritten at runtime
+else
+$(call to-ada-hex,CONFIG_GFX_GMA_DEFAULT_MMIO)
+endif
 
 subdirs-y += ../../../../3rdparty/libgfxinit
 
-ramstage-y += gma.ads gma.adb
+$(foreach stage,$(gfx-gma-stages), \
+	$(eval $(stage)-y += gma.ads gma.adb))
+
+endif # CONFIG_GFX_GMA || CONFIG_EARLY_GFX_GMA
+
+ifeq ($(CONFIG_GFX_GMA),y)
 
 ramstage-$(CONFIG_MAINBOARD_USE_LIBGFXINIT) += gma-gfx_init.ads
 ifeq ($(CONFIG_LINEAR_FRAMEBUFFER),y)
@@ -47,3 +62,11 @@ ramstage-$(CONFIG_MAINBOARD_USE_LIBGFXINIT) += text_fb/gma-gfx_init.adb
 endif
 
 endif # CONFIG_GFX_GMA
+
+ifeq ($(CONFIG_EARLY_GFX_GMA),y)
+
+romstage-$(CONFIG_MAINBOARD_USE_EARLY_LIBGFXINIT) += \
+	gma-gfx_init.ads \
+	text_fb/gma-gfx_init.adb
+
+endif # CONFIG_EARLY_GFX_GMA

src/soc/intel/common/block/graphics/graphics.c

@@ -173,6 +173,18 @@ static void graphics_dev_read_resources(struct device *dev)
 		if (res_bar0->flags & IORESOURCE_PREFETCH)
 			res_bar0->flags &= ~IORESOURCE_PREFETCH;
 	}
+
+	/*
+	 * If libhwbase static MMIO driver is used, IGD BAR 0 has to be set to
+	 * CONFIG_GFX_GMA_DEFAULT_MMIO for the libgfxinit to operate properly.
+	 */
+	if (CONFIG(MAINBOARD_USE_LIBGFXINIT) && CONFIG(HWBASE_STATIC_MMIO)) {
+		struct resource *res_bar0 = find_resource(dev, PCI_BASE_ADDRESS_0);
+		res_bar0->base = CONFIG_GFX_GMA_DEFAULT_MMIO;
+		res_bar0->flags |= IORESOURCE_ASSIGNED;
+		pci_dev_set_resources(dev);
+		res_bar0->flags |= IORESOURCE_FIXED;
+	}
 }
 
 const struct device_operations graphics_ops = {