mpc85xx: Add support for the Varisys Cyrus board

This board runs a P5020 or P5040 chip, and utilizes
an EEPROM with similar formatting to the Freescale P5020DS.

Large amounts of this code were developed by
Adrian Cox <adrian at humboldt dot co dot uk>

Signed-off-by: Andy Fleming <afleming@gmail.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/board/varisys/common/sys_eeprom.c b/board/varisys/common/sys_eeprom.c
new file mode 100644
index 0000000..b55ab81
--- /dev/null
+++ b/board/varisys/common/sys_eeprom.c
@@ -0,0 +1,498 @@
+/*
+ * Based on board/freescale/common/sys_eeprom.c
+ * Copyright 2006, 2008-2009, 2011 Freescale Semiconductor
+ *
+ * This defines the API for storing board information in the
+ * eeprom. It has been adapted from an earlier version of the
+ * Freescale API, but has a number of key differences. Because
+ * the two APIs are independent and may diverge further, the
+ * Varisys version of the API is implemented separately here.
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <i2c.h>
+#include <linux/ctype.h>
+
+#include "eeprom.h"
+
+#ifdef CONFIG_SYS_I2C_EEPROM_NXID_MAC
+#define MAX_NUM_PORTS	CONFIG_SYS_I2C_EEPROM_NXID_MAC
+#else
+#define MAX_NUM_PORTS	8
+#endif
+#define NXID_VERSION	0
+
+/**
+ * static eeprom: EEPROM layout for NXID formats
+ *
+ * See Freescale application note AN3638 for details.
+ */
+static struct __attribute__ ((__packed__)) eeprom {
+	u8 id[4];         /* 0x00 - 0x03 EEPROM Tag 'NXID' */
+	u8 sn[12];        /* 0x04 - 0x0F Serial Number */
+	u8 errata[5];     /* 0x10 - 0x14 Errata Level */
+	u8 date[6];       /* 0x15 - 0x1a Build Date */
+	u8 res_0;         /* 0x1b        Reserved */
+	u32 version;      /* 0x1c - 0x1f NXID Version */
+	u8 tempcal[8];    /* 0x20 - 0x27 Temperature Calibration Factors */
+	u8 tempcalsys[2]; /* 0x28 - 0x29 System Temperature Calibration Factors */
+	u8 tempcalflags;  /* 0x2a        Temperature Calibration Flags */
+	u8 res_1[21];     /* 0x2b - 0x3f Reserved */
+	u8 mac_count;     /* 0x40        Number of MAC addresses */
+	u8 mac_flag;      /* 0x41        MAC table flags */
+	u8 mac[MAX_NUM_PORTS][6];     /* 0x42 - x MAC addresses */
+	u32 crc;          /* x+1         CRC32 checksum */
+} e;
+
+/* Set to 1 if we've read EEPROM into memory */
+static int has_been_read;
+
+/* Is this a valid NXID EEPROM? */
+#define is_valid ((e.id[0] == 'N') || (e.id[1] == 'X') || \
+		  (e.id[2] == 'I') || (e.id[3] == 'D'))
+
+/** Fixed ID field in EEPROM */
+static unsigned char uid[16];
+
+static int eeprom_bus_num = -1;
+static int eeprom_addr;
+static int eeprom_addr_len;
+
+/**
+ * This must be called before any eeprom access.
+ */
+void init_eeprom(int bus_num, int addr, int addr_len)
+{
+	eeprom_bus_num = bus_num;
+	eeprom_addr = addr;
+	eeprom_addr_len = addr_len;
+}
+
+/**
+ * show_eeprom - display the contents of the EEPROM
+ */
+void show_eeprom(void)
+{
+	int i;
+	unsigned int crc;
+
+	/* EEPROM tag ID, either CCID or NXID */
+	printf("ID: %c%c%c%c v%u\n", e.id[0], e.id[1], e.id[2], e.id[3],
+		be32_to_cpu(e.version));
+
+	/* Serial number */
+	printf("SN: %s\n", e.sn);
+
+	printf("UID: ");
+	for (i = 0; i < 16; i++)
+		printf("%02x", uid[i]);
+	printf("\n");
+
+	/* Errata level. */
+	printf("Errata: %s\n", e.errata);
+
+	/* Build date, BCD date values, as YYMMDDhhmmss */
+	printf("Build date: 20%02x/%02x/%02x %02x:%02x:%02x %s\n",
+		e.date[0], e.date[1], e.date[2],
+		e.date[3] & 0x7F, e.date[4], e.date[5],
+		e.date[3] & 0x80 ? "PM" : "");
+
+	/* Show MAC addresses  */
+	for (i = 0; i < min(e.mac_count, (u8)MAX_NUM_PORTS); i++) {
+		u8 *p = e.mac[i];
+
+		printf("Eth%u: %02x:%02x:%02x:%02x:%02x:%02x\n", i,
+		       p[0], p[1], p[2], p[3], p[4], p[5]);
+	}
+
+	crc = crc32(0, (void *)&e, sizeof(e) - 4);
+
+	if (crc == be32_to_cpu(e.crc))
+		printf("CRC: %08x\n", be32_to_cpu(e.crc));
+	else
+		printf("CRC: %08x (should be %08x)\n",
+		       be32_to_cpu(e.crc), crc);
+
+#ifdef DEBUG
+	printf("EEPROM dump: (0x%x bytes)\n", sizeof(e));
+	for (i = 0; i < sizeof(e); i++) {
+		if ((i % 16) == 0)
+			printf("%02X: ", i);
+		printf("%02X ", ((u8 *)&e)[i]);
+		if (((i % 16) == 15) || (i == sizeof(e) - 1))
+			printf("\n");
+	}
+#endif
+}
+
+/**
+ * read_eeprom - read the EEPROM into memory
+ */
+int read_eeprom(void)
+{
+	int ret;
+	unsigned int bus;
+
+	if (eeprom_bus_num < 0) {
+		printf("EEPROM not configured\n");
+		return -1;
+	}
+
+	if (has_been_read)
+		return 0;
+
+	bus = i2c_get_bus_num();
+	i2c_set_bus_num(eeprom_bus_num);
+
+	ret = i2c_read(eeprom_addr, 0, eeprom_addr_len,
+		(void *)&e, sizeof(e));
+
+
+	/* Fixed address of ID field */
+	i2c_read(0x5f, 0x80, 1, uid, 16);
+
+	i2c_set_bus_num(bus);
+
+#ifdef DEBUG
+	show_eeprom();
+#endif
+
+	has_been_read = (ret == 0) ? 1 : 0;
+
+	return ret;
+}
+
+/**
+ *  update_crc - update the CRC
+ *
+ *  This function should be called after each update to the EEPROM structure,
+ *  to make sure the CRC is always correct.
+ */
+static void update_crc(void)
+{
+	u32 crc, crc_offset = offsetof(struct eeprom, crc);
+
+	crc = crc32(0, (void *)&e, crc_offset);
+	e.crc = cpu_to_be32(crc);
+}
+
+/**
+ * prog_eeprom - write the EEPROM from memory
+ */
+static int prog_eeprom(void)
+{
+	int ret = 0;
+	int i;
+	void *p;
+	unsigned int bus;
+
+	if (eeprom_bus_num < 0) {
+		printf("EEPROM not configured\n");
+		return -1;
+	}
+
+	/* Set the reserved values to 0xFF   */
+	e.res_0 = 0xFF;
+	memset(e.res_1, 0xFF, sizeof(e.res_1));
+	update_crc();
+
+	bus = i2c_get_bus_num();
+	i2c_set_bus_num(eeprom_bus_num);
+
+	/*
+	 * The AT24C02 datasheet says that data can only be written in page
+	 * mode, which means 8 bytes at a time, and it takes up to 5ms to
+	 * complete a given write.
+	 */
+	for (i = 0, p = &e; i < sizeof(e); i += 8, p += 8) {
+		ret = i2c_write(eeprom_addr, i, eeprom_addr_len,
+			p, min((int)(sizeof(e) - i), 8));
+		if (ret)
+			break;
+		udelay(5000);	/* 5ms write cycle timing */
+	}
+
+	if (!ret) {
+		/* Verify the write by reading back the EEPROM and comparing */
+		struct eeprom e2;
+
+		ret = i2c_read(eeprom_addr, 0,
+			eeprom_addr_len, (void *)&e2, sizeof(e2));
+		if (!ret && memcmp(&e, &e2, sizeof(e)))
+			ret = -1;
+	}
+
+	i2c_set_bus_num(bus);
+
+	if (ret) {
+		printf("Programming failed.\n");
+		has_been_read = 0;
+		return -1;
+	}
+
+	printf("Programming passed.\n");
+	return 0;
+}
+
+/**
+ * h2i - converts hex character into a number
+ *
+ * This function takes a hexadecimal character (e.g. '7' or 'C') and returns
+ * the integer equivalent.
+ */
+static inline u8 h2i(char p)
+{
+	if ((p >= '0') && (p <= '9'))
+		return p - '0';
+
+	if ((p >= 'A') && (p <= 'F'))
+		return (p - 'A') + 10;
+
+	if ((p >= 'a') && (p <= 'f'))
+		return (p - 'a') + 10;
+
+	return 0;
+}
+
+/**
+ * set_date - stores the build date into the EEPROM
+ *
+ * This function takes a pointer to a string in the format "YYMMDDhhmmss"
+ * (2-digit year, 2-digit month, etc), converts it to a 6-byte BCD string,
+ * and stores it in the build date field of the EEPROM local copy.
+ */
+static void set_date(const char *string)
+{
+	unsigned int i;
+
+	if (strlen(string) != 12) {
+		printf("Usage: mac date YYMMDDhhmmss\n");
+		return;
+	}
+
+	for (i = 0; i < 6; i++)
+		e.date[i] = h2i(string[2 * i]) << 4 | h2i(string[2 * i + 1]);
+
+	update_crc();
+}
+
+/**
+ * set_mac_address - stores a MAC address into the EEPROM
+ *
+ * This function takes a pointer to MAC address string
+ * (i.e."XX:XX:XX:XX:XX:XX", where "XX" is a two-digit hex number) and
+ * stores it in one of the MAC address fields of the EEPROM local copy.
+ */
+static void set_mac_address(unsigned int index, const char *string)
+{
+	char *p = (char *)string;
+	unsigned int i;
+
+	if ((index >= MAX_NUM_PORTS) || !string) {
+		printf("Usage: mac <n> XX:XX:XX:XX:XX:XX\n");
+		return;
+	}
+
+	for (i = 0; *p && (i < 6); i++) {
+		e.mac[index][i] = simple_strtoul(p, &p, 16);
+		if (*p == ':')
+			p++;
+	}
+
+	update_crc();
+}
+
+int do_mac(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	char cmd;
+
+	if (argc == 1) {
+		show_eeprom();
+		return 0;
+	}
+
+	cmd = argv[1][0];
+
+	if (cmd == 'r') {
+		read_eeprom();
+		return 0;
+	}
+
+	if (cmd == 'i') {
+		memcpy(e.id, "NXID", sizeof(e.id));
+		e.version = NXID_VERSION;
+		update_crc();
+		return 0;
+	}
+
+	if (!is_valid) {
+		printf("Please read the EEPROM ('r') and/or set the ID ('i') first.\n");
+		return 0;
+	}
+
+	if (argc == 2) {
+		switch (cmd) {
+		case 's':	/* save */
+			prog_eeprom();
+			break;
+		default:
+			return cmd_usage(cmdtp);
+		}
+
+		return 0;
+	}
+
+	/* We know we have at least one parameter  */
+
+	switch (cmd) {
+	case 'n':	/* serial number */
+		memset(e.sn, 0, sizeof(e.sn));
+		strncpy((char *)e.sn, argv[2], sizeof(e.sn) - 1);
+		update_crc();
+		break;
+	case 'e':	/* errata */
+		memset(e.errata, 0, 5);
+		strncpy((char *)e.errata, argv[2], 4);
+		update_crc();
+		break;
+	case 'd':	/* date BCD format YYMMDDhhmmss */
+		set_date(argv[2]);
+		break;
+	case 'p':	/* MAC table size */
+		e.mac_count = simple_strtoul(argv[2], NULL, 16);
+		update_crc();
+		break;
+	case '0' ... '9':	/* "mac 0" through "mac 22" */
+		set_mac_address(simple_strtoul(argv[1], NULL, 10), argv[2]);
+		break;
+	case 'h':	/* help */
+	default:
+		return cmd_usage(cmdtp);
+	}
+
+	return 0;
+}
+
+int mac_read_from_generic_eeprom(const char *envvar, int chip,
+	int address, int mac_bus)
+{
+	int ret;
+	unsigned int bus;
+	unsigned char mac[6];
+	char ethaddr[18];
+
+	bus = i2c_get_bus_num();
+	i2c_set_bus_num(mac_bus);
+
+	ret = i2c_read(chip, address, 1, mac, 6);
+
+	i2c_set_bus_num(bus);
+
+	if (!ret) {
+		sprintf(ethaddr, "%02X:%02X:%02X:%02X:%02X:%02X",
+			mac[0],
+			mac[1],
+			mac[2],
+			mac[3],
+			mac[4],
+			mac[5]);
+
+		printf("MAC: %s\n", ethaddr);
+		setenv(envvar, ethaddr);
+	}
+
+	return ret;
+}
+
+void mac_read_from_fixed_id(void)
+{
+#ifdef CONFIG_SYS_I2C_MAC1_CHIP_ADDR
+	mac_read_from_generic_eeprom("ethaddr", CONFIG_SYS_I2C_MAC1_CHIP_ADDR,
+		CONFIG_SYS_I2C_MAC1_DATA_ADDR, CONFIG_SYS_I2C_MAC1_BUS);
+#endif
+#ifdef CONFIG_SYS_I2C_MAC2_CHIP_ADDR
+	mac_read_from_generic_eeprom("eth1addr", CONFIG_SYS_I2C_MAC2_CHIP_ADDR,
+		CONFIG_SYS_I2C_MAC2_DATA_ADDR, CONFIG_SYS_I2C_MAC2_BUS);
+#endif
+}
+
+/**
+ * mac_read_from_eeprom - read the MAC addresses from EEPROM
+ *
+ * This function reads the MAC addresses from EEPROM and sets the
+ * appropriate environment variables for each one read.
+ *
+ * The environment variables are only set if they haven't been set already.
+ * This ensures that any user-saved variables are never overwritten.
+ *
+ * This function must be called after relocation.
+ *
+ * For NXID v1 EEPROMs, we support loading and up-converting the older NXID v0
+ * format.  In a v0 EEPROM, there are only eight MAC addresses and the CRC is
+ * located at a different offset.
+ */
+int mac_read_from_eeprom_common(void)
+{
+	unsigned int i;
+	u32 crc, crc_offset = offsetof(struct eeprom, crc);
+	u32 *crcp; /* Pointer to the CRC in the data read from the EEPROM */
+
+	puts("EEPROM: ");
+
+	if (read_eeprom()) {
+		printf("Read failed.\n");
+		return 0;
+	}
+
+	if (!is_valid) {
+		printf("Invalid ID (%02x %02x %02x %02x)\n",
+		       e.id[0], e.id[1], e.id[2], e.id[3]);
+		return 0;
+	}
+
+	crc = crc32(0, (void *)&e, crc_offset);
+	crcp = (void *)&e + crc_offset;
+	if (crc != be32_to_cpu(*crcp)) {
+		printf("CRC mismatch (%08x != %08x)\n", crc,
+			be32_to_cpu(e.crc));
+		return 0;
+	}
+
+	/*
+	 * MAC address #9 in v1 occupies the same position as the CRC in v0.
+	 * Erase it so that it's not mistaken for a MAC address.  We'll
+	 * update the CRC later.
+	 */
+	if (e.version == 0)
+		memset(e.mac[8], 0xff, 6);
+
+	for (i = 0; i < min(e.mac_count, (u8)MAX_NUM_PORTS); i++) {
+		if (memcmp(&e.mac[i], "\0\0\0\0\0\0", 6) &&
+		    memcmp(&e.mac[i], "\xFF\xFF\xFF\xFF\xFF\xFF", 6)) {
+			char ethaddr[18];
+			char enetvar[9];
+
+			sprintf(ethaddr, "%02X:%02X:%02X:%02X:%02X:%02X",
+				e.mac[i][0],
+				e.mac[i][1],
+				e.mac[i][2],
+				e.mac[i][3],
+				e.mac[i][4],
+				e.mac[i][5]);
+			sprintf(enetvar, i ? "eth%daddr" : "ethaddr", i);
+			/* Only initialize environment variables that are blank
+			 * (i.e. have not yet been set)
+			 */
+			if (!getenv(enetvar))
+				setenv(enetvar, ethaddr);
+		}
+	}
+
+	printf("%c%c%c%c v%u\n", e.id[0], e.id[1], e.id[2], e.id[3],
+		be32_to_cpu(e.version));
+
+	return 0;
+}