sunxi: setup simplefb for Allwinner DE2

As the support of EFI boot on Allwinner H3 is broken, we still need to
use simplefb to pass the framebuffer to Linux.

Add code to setup simplefb for Allwinner DE2 driver.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/mach-sunxi/Kconfig

@@ -770,6 +770,7 @@ config VIDEO_DE2
 	depends on SUNXI_DE2
 	select DM_VIDEO
 	select DISPLAY
+	imply VIDEO_DT_SIMPLEFB
 	default y
 	---help---
 	Say y here if you want to build DE2 video driver which is present on

drivers/video/sunxi/Makefile

@@ -6,4 +6,4 @@
 #
 
 obj-$(CONFIG_VIDEO_SUNXI) += sunxi_display.o simplefb_common.o lcdc.o tve_common.o ../videomodes.o
-obj-$(CONFIG_VIDEO_DE2) += sunxi_de2.o sunxi_dw_hdmi.o lcdc.o ../dw_hdmi.o
+obj-$(CONFIG_VIDEO_DE2) += sunxi_de2.o sunxi_dw_hdmi.o simplefb_common.o lcdc.o ../dw_hdmi.o

drivers/video/sunxi/sunxi_de2.c

@@ -10,6 +10,8 @@
 #include <display.h>
 #include <dm.h>
 #include <edid.h>
+#include <fdtdec.h>
+#include <fdt_support.h>
 #include <video.h>
 #include <asm/global_data.h>
 #include <asm/io.h>
@@ -17,6 +19,7 @@
 #include <asm/arch/display2.h>
 #include <dm/device-internal.h>
 #include <dm/uclass-internal.h>
+#include "simplefb_common.h"
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -292,3 +295,72 @@ U_BOOT_DRIVER(sunxi_de2) = {
 U_BOOT_DEVICE(sunxi_de2) = {
 	.name = "sunxi_de2"
 };
+
+/*
+ * Simplefb support.
+ */
+#if defined(CONFIG_OF_BOARD_SETUP) && defined(CONFIG_VIDEO_DT_SIMPLEFB)
+int sunxi_simplefb_setup(void *blob)
+{
+	struct udevice *de2, *hdmi;
+	struct video_priv *de2_priv;
+	struct video_uc_platdata *de2_plat;
+	int mux;
+	int offset, ret;
+	u64 start, size;
+	const char *pipeline = NULL;
+
+	debug("Setting up simplefb\n");
+
+	if (IS_ENABLED(CONFIG_MACH_SUNXI_H3_H5))
+		mux = 0;
+	else
+		mux = 1;
+
+	/* Skip simplefb setting if DE2 / HDMI is not present */
+	ret = uclass_find_device_by_name(UCLASS_VIDEO,
+					 "sunxi_de2", &de2);
+	if (ret) {
+		debug("DE2 not present\n");
+		return 0;
+	}
+
+	ret = uclass_find_device_by_name(UCLASS_DISPLAY,
+					 "sunxi_dw_hdmi", &hdmi);
+	if (ret) {
+		debug("HDMI not present\n");
+		return 0;
+	}
+
+	if (mux == 0)
+		pipeline = "mixer0-lcd0-hdmi";
+	else
+		pipeline = "mixer1-lcd1-hdmi";
+
+	de2_priv = dev_get_uclass_priv(de2);
+	de2_plat = dev_get_uclass_platdata(de2);
+
+	offset = sunxi_simplefb_fdt_match(blob, pipeline);
+	if (offset < 0) {
+		eprintf("Cannot setup simplefb: node not found\n");
+		return 0; /* Keep older kernels working */
+	}
+
+	start = gd->bd->bi_dram[0].start;
+	size = de2_plat->base - start;
+	ret = fdt_fixup_memory_banks(blob, &start, &size, 1);
+	if (ret) {
+		eprintf("Cannot setup simplefb: Error reserving memory\n");
+		return ret;
+	}
+
+	ret = fdt_setup_simplefb_node(blob, offset, de2_plat->base,
+			de2_priv->xsize, de2_priv->ysize,
+			VNBYTES(de2_priv->bpix) * de2_priv->xsize,
+			"x8r8g8b8");
+	if (ret)
+		eprintf("Cannot setup simplefb: Error setting properties\n");
+
+	return ret;
+}
+#endif /* CONFIG_OF_BOARD_SETUP && CONFIG_VIDEO_DT_SIMPLEFB */