avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/board/gateworks/gw_ventana/eeprom.c

@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2014 Gateworks Corporation
+ * Author: Tim Harvey <tharvey@gateworks.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <i2c.h>
+#include <malloc.h>
+#include <asm/bitops.h>
+
+#include "gsc.h"
+#include "ventana_eeprom.h"
+
+/* read ventana EEPROM, check for validity, and return baseboard type */
+int
+read_eeprom(int bus, struct ventana_board_info *info)
+{
+	int i;
+	int chksum;
+	char baseboard;
+	int type;
+	unsigned char *buf = (unsigned char *)info;
+
+	memset(info, 0, sizeof(*info));
+
+	/*
+	 * On a board with a missing/depleted backup battery for GSC, the
+	 * board may be ready to probe the GSC before its firmware is
+	 * running.  We will wait here indefinately for the GSC/EEPROM.
+	 */
+	while (1) {
+		if (0 == i2c_set_bus_num(bus) &&
+		    0 == i2c_probe(GSC_EEPROM_ADDR))
+			break;
+		mdelay(1);
+	}
+
+	/* read eeprom config section */
+	if (gsc_i2c_read(GSC_EEPROM_ADDR, 0x00, 1, buf, sizeof(*info))) {
+		puts("EEPROM: Failed to read EEPROM\n");
+		return GW_UNKNOWN;
+	}
+
+	/* sanity checks */
+	if (info->model[0] != 'G' || info->model[1] != 'W') {
+		puts("EEPROM: Invalid Model in EEPROM\n");
+		return GW_UNKNOWN;
+	}
+
+	/* validate checksum */
+	for (chksum = 0, i = 0; i < sizeof(*info)-2; i++)
+		chksum += buf[i];
+	if ((info->chksum[0] != chksum>>8) ||
+	    (info->chksum[1] != (chksum&0xff))) {
+		puts("EEPROM: Failed EEPROM checksum\n");
+		return GW_UNKNOWN;
+	}
+
+	/* original GW5400-A prototype */
+	baseboard = info->model[3];
+	if (strncasecmp((const char *)info->model, "GW5400-A", 8) == 0)
+		baseboard = '0';
+
+	switch (baseboard) {
+	case '0': /* original GW5400-A prototype */
+		type = GW54proto;
+		break;
+	case '1':
+		type = GW51xx;
+		break;
+	case '2':
+		type = GW52xx;
+		break;
+	case '3':
+		type = GW53xx;
+		break;
+	case '4':
+		type = GW54xx;
+		break;
+	case '5':
+		if (info->model[4] == '1') {
+			type = GW551x;
+			break;
+		} else if (info->model[4] == '2') {
+			type = GW552x;
+			break;
+		} else if (info->model[4] == '3') {
+			type = GW553x;
+			break;
+		}
+		/* fall through */
+	default:
+		printf("EEPROM: Unknown model in EEPROM: %s\n", info->model);
+		type = GW_UNKNOWN;
+		break;
+	}
+	return type;
+}
+
+/* list of config bits that the bootloader will remove from dtb if not set */
+struct ventana_eeprom_config econfig[] = {
+	{ "eth0", "ethernet0", EECONFIG_ETH0 },
+	{ "usb0", NULL, EECONFIG_USB0 },
+	{ "usb1", NULL, EECONFIG_USB1 },
+	{ "mmc0", NULL, EECONFIG_SD0 },
+	{ "mmc1", NULL, EECONFIG_SD1 },
+	{ "mmc2", NULL, EECONFIG_SD2 },
+	{ "mmc3", NULL, EECONFIG_SD3 },
+	{ /* Sentinel */ }
+};
+
+#ifdef CONFIG_CMD_EECONFIG
+static struct ventana_eeprom_config *get_config(const char *name)
+{
+	struct ventana_eeprom_config *cfg = econfig;
+
+	while (cfg->name) {
+		if (0 == strcmp(name, cfg->name))
+			return cfg;
+		cfg++;
+	}
+	return NULL;
+}
+
+static u8 econfig_bytes[sizeof(ventana_info.config)];
+static int econfig_init = -1;
+
+int do_econfig(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	struct ventana_eeprom_config *cfg;
+	struct ventana_board_info *info = &ventana_info;
+	int i;
+
+	if (argc < 2)
+		return CMD_RET_USAGE;
+
+	/* initialize */
+	if (econfig_init != 1) {
+		memcpy(econfig_bytes, info->config, sizeof(econfig_bytes));
+		econfig_init = 1;
+	}
+
+	/* list configs */
+	if ((strncmp(argv[1], "list", 4) == 0)) {
+		cfg = econfig;
+		while (cfg->name) {
+			printf("%s: %d\n", cfg->name,
+			       test_bit(cfg->bit, econfig_bytes) ?  1 : 0);
+			cfg++;
+		}
+	}
+
+	/* save */
+	else if ((strncmp(argv[1], "save", 4) == 0)) {
+		unsigned char *buf = (unsigned char *)info;
+		int chksum;
+
+		/* calculate new checksum */
+		memcpy(info->config, econfig_bytes, sizeof(econfig_bytes));
+		for (chksum = 0, i = 0; i < sizeof(*info)-2; i++)
+			chksum += buf[i];
+		debug("old chksum:0x%04x\n",
+		      (info->chksum[0] << 8) | info->chksum[1]);
+		debug("new chksum:0x%04x\n", chksum);
+		info->chksum[0] = chksum >> 8;
+		info->chksum[1] = chksum & 0xff;
+
+		/* write new config data */
+		if (gsc_i2c_write(GSC_EEPROM_ADDR, info->config - (u8 *)info,
+				  1, econfig_bytes, sizeof(econfig_bytes))) {
+			printf("EEPROM: Failed updating config\n");
+			return CMD_RET_FAILURE;
+		}
+
+		/* write new config data */
+		if (gsc_i2c_write(GSC_EEPROM_ADDR, info->chksum - (u8 *)info,
+				  1, info->chksum, 2)) {
+			printf("EEPROM: Failed updating checksum\n");
+			return CMD_RET_FAILURE;
+		}
+
+		printf("Config saved to EEPROM\n");
+	}
+
+	/* get config */
+	else if (argc == 2) {
+		cfg = get_config(argv[1]);
+		if (cfg) {
+			printf("%s: %d\n", cfg->name,
+			       test_bit(cfg->bit, econfig_bytes) ? 1 : 0);
+		} else {
+			printf("invalid config: %s\n", argv[1]);
+			return CMD_RET_FAILURE;
+		}
+	}
+
+	/* set config */
+	else if (argc == 3) {
+		cfg = get_config(argv[1]);
+		if (cfg) {
+			if (simple_strtol(argv[2], NULL, 10)) {
+				test_and_set_bit(cfg->bit, econfig_bytes);
+				printf("Enabled %s\n", cfg->name);
+			} else {
+				test_and_clear_bit(cfg->bit, econfig_bytes);
+				printf("Disabled %s\n", cfg->name);
+			}
+		} else {
+			printf("invalid config: %s\n", argv[1]);
+			return CMD_RET_FAILURE;
+		}
+	}
+
+	else
+		return CMD_RET_USAGE;
+
+	return CMD_RET_SUCCESS;
+}
+
+U_BOOT_CMD(
+	econfig, 3, 0, do_econfig,
+	"EEPROM configuration",
+	"list - list config\n"
+	"save - save config to EEPROM\n"
+	"<name> - get config 'name'\n"
+	"<name> [0|1] - set config 'name' to value\n"
+);
+
+#endif /* CONFIG_CMD_EECONFIG */