board: stemmy: Detect board variants and patch DTB

This patch scans the cmdline from the Samsung SBL (second stage
bootloader) and stores the parameters board_id=N and lcdtype=N
in order to augment the DTB for different board and LCD types.

We then add a custom ft_board_setup() callback that will inspect
the DTB and patch it using the stored LCD type. At this point
we know which product we are dealing with, so using the passed
board_id we can also print the board variant for diagnostics.

We patch the Codina, Skomer and Kyle DTBs to use the right
LCD type as passed in lcdtype from the SBL.

This also creates an infrastructure for handling any other
Samsung U8500 board variants that may need a slightly augmented
DTB.

Cc: Markuss Broks <markuss.broks@gmail.com>
Cc: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/board/ste/stemmy/stemmy.c b/board/ste/stemmy/stemmy.c
index 5f1150c..060d562 100644
--- a/board/ste/stemmy/stemmy.c
+++ b/board/ste/stemmy/stemmy.c
@@ -4,6 +4,7 @@
  */
 #include <common.h>
 #include <env.h>
+#include <fdt_support.h>
 #include <init.h>
 #include <log.h>
 #include <stdlib.h>
@@ -95,6 +96,33 @@
 	env_set("serial#", serial);
 }
 
+#define SBL_BOARD "board_id="
+#define SBL_LCDTYPE "lcdtype="
+static ulong board_id = 0;
+static ulong lcdtype = 0;
+
+static void parse_cmdline(const struct tag_cmdline *cmdline)
+{
+	char *buf;
+
+	/* Export this to sbl_cmdline (secondary boot loader command line) */
+	env_set("sbl_cmdline", cmdline->cmdline);
+
+	buf = strstr(cmdline->cmdline, SBL_BOARD);
+	if (!buf)
+		return;
+	buf += strlen(SBL_BOARD);
+
+	board_id = simple_strtoul(buf, NULL, 10);
+
+	buf = strstr(cmdline->cmdline, SBL_LCDTYPE);
+	if (!buf)
+		return;
+	buf += strlen(SBL_LCDTYPE);
+
+	lcdtype = simple_strtoul(buf, NULL, 10);
+}
+
 /*
  * The downstream/vendor kernel (provided by Samsung) uses ATAGS for booting.
  * It also requires an extremely long cmdline provided by the primary bootloader
@@ -126,6 +154,9 @@
 		if (t->hdr.tag == ATAG_SERIAL)
 			parse_serial(&t->u.serialnr);
 
+		if (t->hdr.tag == ATAG_CMDLINE)
+			parse_cmdline(&t->u.cmdline);
+
 		fw_atags_size += t->hdr.size * sizeof(u32);
 	}
 
@@ -165,3 +196,287 @@
 	memcpy(*in_params, fw_atags_copy, fw_atags_size);
 	*(u8 **)in_params += fw_atags_size;
 }
+
+/* These numbers are unique per product but not across all products */
+#define SAMSUNG_CODINA_LCD_LMS380KF01 4
+#define SAMSUNG_CODINA_LCD_S6D27A1 13
+#define SAMSUNG_SKOMER_LCD_HVA40WV1 10
+#define SAMSUNG_SKOMER_LCD_NT35512 12
+
+static void codina_patch_display(void *fdt)
+{
+	int node;
+	int ret;
+
+	node = fdt_path_offset(fdt, "/spi-gpio-0/panel");
+	if (node < 0) {
+		printf("cannot find Codina panel node\n");
+		return;
+	}
+	if (lcdtype == SAMSUNG_CODINA_LCD_LMS380KF01) {
+		ret = fdt_setprop_string(fdt, node, "compatible", "samsung,lms380kf01");
+		if (ret < 0)
+			printf("could not set LCD compatible\n");
+		else
+			printf("updated LCD compatible to LMS380KF01\n");
+	} else if (lcdtype == SAMSUNG_CODINA_LCD_S6D27A1) {
+		ret = fdt_setprop_string(fdt, node, "compatible", "samsung,s6d27a1");
+		if (ret < 0)
+			printf("could not set LCD compatible\n");
+		else
+			printf("updated LCD compatible to S6D27A1\n");
+	} else {
+		printf("unknown LCD type\n");
+	}
+}
+
+static void skomer_kyle_patch_display(void *fdt)
+{
+	int node;
+	int ret;
+
+	node = fdt_path_offset(fdt, "/soc/mcde/dsi/panel");
+	if (node < 0) {
+		printf("cannot find Skomer/Kyle panel node\n");
+		return;
+	}
+	if (lcdtype == SAMSUNG_SKOMER_LCD_HVA40WV1) {
+		ret = fdt_setprop_string(fdt, node, "compatible", "hydis,hva40wv1");
+		if (ret < 0)
+			printf("could not set LCD compatible\n");
+		else
+			printf("updated LCD compatible to Hydis HVA40WV1\n");
+	} else if (lcdtype == SAMSUNG_SKOMER_LCD_NT35512) {
+		/*
+		 * FIXME: This panel is actually a BOE product, but we don't know
+		 * the exact product name, so the compatible for the NT35512
+		 * is used for the time being. The vendor drivers also call it NT35512.
+		 */
+		ret = fdt_setprop_string(fdt, node, "compatible", "novatek,nt35512");
+		if (ret < 0)
+			printf("could not set LCD compatible\n");
+		else
+			printf("updated LCD compatible to Novatek NT35512\n");
+	} else {
+		printf("unknown LCD type\n");
+	}
+}
+
+int ft_board_setup(void *fdt, struct bd_info *bd)
+{
+	const char *str;
+	int node;
+	int ret;
+
+	printf("stemmy patch: DTB at 0x%08lx\n", (ulong)fdt);
+
+	/* Inspect FDT to see what we've got here */
+	ret = fdt_check_header(fdt);
+	if (ret < 0) {
+		printf("invalid DTB\n");
+		return ret;
+	}
+	node = fdt_path_offset(fdt, "/");
+	if (node < 0) {
+		printf("cannot find root node\n");
+		return node;
+	}
+	str = fdt_stringlist_get(fdt, node, "compatible", 0, NULL);
+	if (!str) {
+		printf("could not find board compatible\n");
+		return -1;
+	}
+
+	if (!strcmp(str, "samsung,janice")) {
+		switch(board_id) {
+		case 7:
+			printf("Janice GT-I9070 Board Rev 0.0\n");
+			break;
+		case 8:
+			printf("Janice GT-I9070 Board Rev 0.1\n");
+			break;
+		case 9:
+			printf("Janice GT-I9070 Board Rev 0.2\n");
+			break;
+		case 10:
+			printf("Janice GT-I9070 Board Rev 0.3\n");
+			break;
+		case 11:
+			printf("Janice GT-I9070 Board Rev 0.4\n");
+			break;
+		case 12:
+			printf("Janice GT-I9070 Board Rev 0.5\n");
+			break;
+		case 13:
+			printf("Janice GT-I9070 Board Rev 0.6\n");
+			break;
+		default:
+			break;
+		}
+	} else if (!strcmp(str, "samsung,gavini")) {
+		switch(board_id) {
+		case 7:
+			printf("Gavini GT-I8530 Board Rev 0.0\n");
+			break;
+		case 8:
+			printf("Gavini GT-I8530 Board Rev 0.0A\n");
+			break;
+		case 9:
+			printf("Gavini GT-I8530 Board Rev 0.0B\n");
+			break;
+		case 10:
+			printf("Gavini GT-I8530 Board Rev 0.0A_EMUL\n");
+			break;
+		case 11:
+			printf("Gavini GT-I8530 Board Rev 0.0C\n");
+			break;
+		case 12:
+			printf("Gavini GT-I8530 Board Rev 0.0D\n");
+			break;
+		case 13:
+			printf("Gavini GT-I8530 Board Rev 0.1\n");
+			break;
+		case 14:
+			printf("Gavini GT-I8530 Board Rev 0.3\n");
+			break;
+		default:
+			break;
+		}
+	} else if (!strcmp(str, "samsung,codina")) {
+		switch(board_id) {
+		case 7:
+			printf("Codina GT-I8160 Board Rev 0.0\n");
+			break;
+		case 8:
+			printf("Codina GT-I8160 Board Rev 0.1\n");
+			break;
+		case 9:
+			printf("Codina GT-I8160 Board Rev 0.2\n");
+			break;
+		case 10:
+			printf("Codina GT-I8160 Board Rev 0.3\n");
+			break;
+		case 11:
+			printf("Codina GT-I8160 Board Rev 0.4\n");
+			break;
+		case 12:
+			printf("Codina GT-I8160 Board Rev 0.5\n");
+			break;
+		default:
+			break;
+		}
+		codina_patch_display(fdt);
+	} else if (!strcmp(str, "samsung,codina-tmo")) {
+		switch(board_id) {
+		case 0x101:
+			printf("Codina SGH-T599 Board pre-Rev 0.0\n");
+			break;
+		case 0x102:
+			printf("Codina SGH-T599 Board Rev 0.0\n");
+			break;
+		case 0x103:
+			printf("Codina SGH-T599 Board Rev 0.1\n");
+			break;
+		case 0x104:
+			printf("Codina SGH-T599 Board Rev 0.2\n");
+			break;
+		case 0x105:
+			printf("Codina SGH-T599 Board Rev 0.4\n");
+			break;
+		case 0x106:
+			printf("Codina SGH-T599 Board Rev 0.6\n");
+			break;
+		case 0x107:
+			printf("Codina SGH-T599 Board Rev 0.7\n");
+			break;
+		default:
+			break;
+		}
+		codina_patch_display(fdt);
+	} else if (!strcmp(str, "samsung,golden")) {
+		switch(board_id) {
+		case 0x102:
+			printf("Golden GT-I8190 Board SW bringup\n");
+			break;
+		case 0x103:
+			printf("Golden GT-I8190 Board Rev 0.2\n");
+			break;
+		case 0x104:
+			printf("Golden GT-I8190 Board Rev 0.3\n");
+			break;
+		case 0x105:
+			printf("Golden GT-I8190 Board Rev 0.4\n");
+			break;
+		case 0x106:
+			printf("Golden GT-I8190 Board Rev 0.5\n");
+			break;
+		case 0x107:
+			printf("Golden GT-I8190 Board Rev 0.6\n");
+			break;
+		default:
+			break;
+		}
+	} else if (!strcmp(str, "samsung,skomer")) {
+		switch(board_id) {
+		case 0x101:
+			printf("Skomer GT-S7710 Board Rev 0.0\n");
+			break;
+		case 0x102:
+			printf("Skomer GT-S7710 Board Rev 0.1\n");
+			break;
+		case 0x103:
+			printf("Skomer GT-S7710 Board Rev 0.2\n");
+			break;
+		case 0x104:
+			printf("Skomer GT-S7710 Board Rev 0.3\n");
+			break;
+		case 0x105:
+			printf("Skomer GT-S7710 Board Rev 0.4\n");
+			break;
+		case 0x106:
+			printf("Skomer GT-S7710 Board Rev 0.5\n");
+			break;
+		case 0x107:
+			printf("Skomer GT-S7710 Board Rev 0.6\n");
+			break;
+		case 0x108:
+			printf("Skomer GT-S7710 Board Rev 0.7\n");
+			break;
+		case 0x109:
+			printf("Skomer GT-S7710 Board Rev 0.8\n");
+			break;
+		default:
+			break;
+		}
+		skomer_kyle_patch_display(fdt);
+	} else if (!strcmp(str, "samsung,kyle")) {
+		switch(board_id) {
+		case 0x101:
+			printf("Kyle SGH-I407 Board Rev 0.0\n");
+			break;
+		case 0x102:
+			printf("Kyle SGH-I407 Board Rev 0.1\n");
+			break;
+		case 0x103:
+			printf("Kyle SGH-I407 Board Rev 0.2\n");
+			break;
+		case 0x104:
+			printf("Kyle SGH-I407 Board Rev 0.3\n");
+			break;
+		case 0x105:
+			printf("Kyle SGH-I407 Board Rev 0.4\n");
+			break;
+		case 0x106:
+			printf("Kyle SGH-I407 Board Rev 0.5\n");
+			break;
+		case 0x107:
+			printf("Kyle SGH-I407 Board Rev 0.6\n");
+			break;
+		default:
+			break;
+		}
+		skomer_kyle_patch_display(fdt);
+	}
+
+	return 0;
+}
diff --git a/configs/stemmy_defconfig b/configs/stemmy_defconfig
index ea43cb6..c02db99 100644
--- a/configs/stemmy_defconfig
+++ b/configs/stemmy_defconfig
@@ -36,3 +36,5 @@
 CONFIG_SYS_WHITE_ON_BLACK=y
 CONFIG_VIDEO_MCDE_SIMPLE=y
 # CONFIG_EFI_LOADER is not set
+CONFIG_OF_BOARD_SETUP=y
+CONFIG_OF_LIBFDT=y