[PATCH 24/26] imx8mn_bsh_smm_s2/pro: support simple frame-buffer

[Dario Binacchi]

If you want to pass the frame-buffer to the kernel, the video output is
initialized by U-Boot, and kept by the kernel. The commit modifies the
device tree to be passed to the kernel just before launching it, to
prevent the kernel from reinitializing hardware that has already been
configured by the bootloader.

Co-developed-by: Michael Trimarchi <michael at amarulasolutions.com>
Signed-off-by: Michael Trimarchi <michael at amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi at amarulasolutions.com>
---

 board/bsh/imx8mn_smm_s2/imx8mn_smm_s2.c | 99 +++++++++++++++++++++++++
 1 file changed, 99 insertions(+)

diff --git a/board/bsh/imx8mn_smm_s2/imx8mn_smm_s2.c b/board/bsh/imx8mn_smm_s2/imx8mn_smm_s2.c
index c99896873991..87eb4e7ed63e 100644
--- a/board/bsh/imx8mn_smm_s2/imx8mn_smm_s2.c
+++ b/board/bsh/imx8mn_smm_s2/imx8mn_smm_s2.c
@@ -5,6 +5,8 @@
 
 #include <asm/arch/sys_proto.h>
 #include <env.h>
+#include <fdt_simplefb.h>
+#include <fdt_support.h>
 
 int board_init(void)
 {
@@ -20,3 +22,100 @@ int board_late_init(void)
 
 	return 0;
 }
+
+#if (IS_ENABLED(CONFIG_OF_LIBFDT) && IS_ENABLED(CONFIG_FDT_SIMPLEFB) && \
+	IS_ENABLED(CONFIG_VIDEO))
+static void smm_s2_setup_simplefb(void *blob)
+{
+#define DT_BLK_CTRL_NODE_PATH "/soc at 0/bus at 32c00000/blk-ctrl at 32e28000"
+#define DT_GPC_NODE_PATH "/soc at 0/bus at 30000000/gpc at 303a0000"
+#define DT_MIPI_DSI_NODE_PATH "/soc at 0/bus at 32c00000/dsi at 32e10000"
+#define DT_LCDIF_NODE_PATH "/soc at 0/bus at 32c00000/lcdif at 32e00000"
+
+	const char *dt_addnode[][2] = {
+		{ DT_BLK_CTRL_NODE_PATH, "lcdif" },
+		{ DT_BLK_CTRL_NODE_PATH, "mipi-dsi" },
+	};
+
+	const char *dt_addprop[][2] = {
+		{ "/regulator-3v3-O2", "regulator-boot-on" },
+		{ "/regulator-3v3-O3", "regulator-boot-on" },
+		{ DT_GPC_NODE_PATH "/pgc/power-domain at 3", "fsl,boot-on" },
+		{ DT_GPC_NODE_PATH "/pgc/power-domain at 4", "fsl,boot-on" },
+		{ DT_BLK_CTRL_NODE_PATH "/lcdif", "fsl,boot-on" },
+		{ DT_BLK_CTRL_NODE_PATH "/mipi-dsi", "fsl,boot-on" },
+		{ DT_MIPI_DSI_NODE_PATH, "samsung,boot-on" },
+		{ DT_MIPI_DSI_NODE_PATH "/panel at 0", "syna,boot-on" },
+		{ DT_LCDIF_NODE_PATH, "fsl,boot-on" },
+	};
+	const char *dt_delprop[][2] = {
+		{ DT_BLK_CTRL_NODE_PATH, "assigned-clock-rates" },
+		{ DT_GPC_NODE_PATH "/pgc/power-domain at 3", "assigned-clock-rates" }, // pgc_dispmix
+		{ DT_LCDIF_NODE_PATH, "assigned-clock-rates" },
+	};
+	int i, ret, offset;
+
+	ret = fdt_simplefb_enable_and_mem_rsv(blob);
+	if (ret) {
+		printf("Failed to enable framebuffer DTS node\n");
+		return;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(dt_addnode); i++) {
+		const char *path = dt_addnode[i][0];
+		const char *node = dt_addnode[i][1];
+
+		offset = fdt_path_offset(blob, path);
+		if (offset < 0) {
+			printf("Missing node %s, err=%s\n", path,
+			       fdt_strerror(offset));
+			continue;
+		}
+
+		offset = fdt_find_or_add_subnode(blob, offset, node);
+		if (offset < 0)
+			printf("Failed to create node %s, err=%s\n", path,
+			       fdt_strerror(offset));
+		else
+			debug("Add node %s:%s\n", path, node);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(dt_addprop); i++) {
+		const char *path = dt_addprop[i][0];
+		const char *prop = dt_addprop[i][1];
+
+		ret = fdt_find_and_setprop(blob, path, prop, NULL, 0, 1);
+		if (ret < 0)
+			printf("Failed to add property %s:%s, err=%s\n", path, prop,
+			       fdt_strerror(ret));
+		else
+			debug("Add property %s:%s\n", path, prop);
+	}
+
+	for (i = 0; i < ARRAY_SIZE(dt_delprop); i++) {
+		const char *path = dt_delprop[i][0];
+		const char *prop = dt_delprop[i][1];
+
+		offset = fdt_path_offset(blob, path);
+		if (offset < 0) {
+			printf("Missing node %s\n", path);
+			continue;
+		}
+
+		ret = fdt_delprop(blob, offset, prop);
+		if (ret < 0)
+			printf("Failed to delete property %s:%s\n", path, prop);
+		else
+			debug("Delete property %s:%s\n", path, prop);
+	}
+}
+#endif
+
+int ft_board_setup(void *blob, struct bd_info *bd)
+{
+	if (IS_ENABLED(CONFIG_OF_LIBFDT) && IS_ENABLED(CONFIG_FDT_SIMPLEFB) &&
+	    IS_ENABLED(CONFIG_VIDEO))
+		smm_s2_setup_simplefb(blob);
+
+	return 0;
+}
-- 
2.43.0