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|
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2021 Gateworks Corporation
*/
#include <common.h>
#include <command.h>
#include <hang.h>
#include <hexdump.h>
#include <i2c.h>
#include <linux/delay.h>
#include <dm/uclass.h>
#include "gsc.h"
DECLARE_GLOBAL_DATA_PTR;
struct venice_board_info som_info;
struct venice_board_info base_info;
char venice_model[32];
/* return a mac address from EEPROM info */
int gsc_getmac(int index, uint8_t *address)
{
int i, j;
u32 maclow, machigh;
u64 mac;
j = 0;
if (som_info.macno) {
maclow = som_info.mac[5];
maclow |= som_info.mac[4] << 8;
maclow |= som_info.mac[3] << 16;
maclow |= som_info.mac[2] << 24;
machigh = som_info.mac[1];
machigh |= som_info.mac[0] << 8;
mac = machigh;
mac <<= 32;
mac |= maclow;
for (i = 0; i < som_info.macno; i++, j++) {
if (index == j)
goto out;
}
}
maclow = base_info.mac[5];
maclow |= base_info.mac[4] << 8;
maclow |= base_info.mac[3] << 16;
maclow |= base_info.mac[2] << 24;
machigh = base_info.mac[1];
machigh |= base_info.mac[0] << 8;
mac = machigh;
mac <<= 32;
mac |= maclow;
for (i = 0; i < base_info.macno; i++, j++) {
if (index == j)
goto out;
}
return -EINVAL;
out:
mac += i;
address[0] = (mac >> 40) & 0xff;
address[1] = (mac >> 32) & 0xff;
address[2] = (mac >> 24) & 0xff;
address[3] = (mac >> 16) & 0xff;
address[4] = (mac >> 8) & 0xff;
address[5] = (mac >> 0) & 0xff;
return 0;
}
/* System Controller registers */
enum {
GSC_SC_CTRL0 = 0,
GSC_SC_CTRL1 = 1,
GSC_SC_STATUS = 10,
GSC_SC_FWCRC = 12,
GSC_SC_FWVER = 14,
GSC_SC_WP = 15,
GSC_SC_RST_CAUSE = 16,
GSC_SC_THERM_PROTECT = 19,
};
/* System Controller Control1 bits */
enum {
GSC_SC_CTRL1_WDTIME = 4, /* 1 = 60s timeout, 0 = 30s timeout */
GSC_SC_CTRL1_WDEN = 5, /* 1 = enable, 0 = disable */
GSC_SC_CTRL1_BOOT_CHK = 6, /* 1 = enable alt boot check */
GSC_SC_CTRL1_WDDIS = 7, /* 1 = disable boot watchdog */
};
/* System Controller Interrupt bits */
enum {
GSC_SC_IRQ_PB = 0, /* Pushbutton switch */
GSC_SC_IRQ_SECURE = 1, /* Secure Key erase operation complete */
GSC_SC_IRQ_EEPROM_WP = 2, /* EEPROM write violation */
GSC_SC_IRQ_GPIO = 4, /* GPIO change */
GSC_SC_IRQ_TAMPER = 5, /* Tamper detect */
GSC_SC_IRQ_WATCHDOG = 6, /* Watchdog trip */
GSC_SC_IRQ_PBLONG = 7, /* Pushbutton long hold */
};
/* System Controller WP bits */
enum {
GSC_SC_WP_ALL = 0, /* Write Protect All EEPROM regions */
GSC_SC_WP_BOARDINFO = 1, /* Write Protect Board Info region */
};
/* System Controller Reset Cause */
enum {
GSC_SC_RST_CAUSE_VIN = 0,
GSC_SC_RST_CAUSE_PB = 1,
GSC_SC_RST_CAUSE_WDT = 2,
GSC_SC_RST_CAUSE_CPU = 3,
GSC_SC_RST_CAUSE_TEMP_LOCAL = 4,
GSC_SC_RST_CAUSE_TEMP_REMOTE = 5,
GSC_SC_RST_CAUSE_SLEEP = 6,
GSC_SC_RST_CAUSE_BOOT_WDT = 7,
GSC_SC_RST_CAUSE_BOOT_WDT_MAN = 8,
GSC_SC_RST_CAUSE_SOFT_PWR = 9,
GSC_SC_RST_CAUSE_MAX = 10,
};
#include <dm/device.h>
static struct udevice *gsc_get_dev(int busno, int slave)
{
struct udevice *dev, *bus;
int ret;
ret = uclass_get_device_by_seq(UCLASS_I2C, busno, &bus);
if (ret) {
printf("GSC : failed I2C%d probe: %d\n", busno, ret);
return NULL;
}
ret = dm_i2c_probe(bus, slave, 0, &dev);
if (ret)
return NULL;
return dev;
}
static int gsc_read_eeprom(int bus, int slave, int alen, struct venice_board_info *info)
{
int i;
int chksum;
unsigned char *buf = (unsigned char *)info;
struct udevice *dev;
int ret;
/* probe device */
dev = gsc_get_dev(bus, slave);
if (!dev) {
if (slave == GSC_EEPROM_ADDR)
puts("ERROR: Failed to probe EEPROM\n");
return -ENODEV;
}
/* read eeprom config section */
memset(info, 0, sizeof(*info));
ret = i2c_set_chip_offset_len(dev, alen);
if (ret) {
puts("EEPROM: Failed to set alen\n");
return ret;
}
ret = dm_i2c_read(dev, 0x00, buf, sizeof(*info));
if (ret) {
if (slave == GSC_EEPROM_ADDR)
printf("EEPROM: Failed to read EEPROM\n");
return ret;
}
/* validate checksum */
for (chksum = 0, i = 0; i < (int)sizeof(*info) - 2; i++)
chksum += buf[i];
if ((info->chksum[0] != chksum >> 8) ||
(info->chksum[1] != (chksum & 0xff))) {
printf("EEPROM: I2C%d@0x%02x: Invalid Checksum\n", bus, slave);
print_hex_dump_bytes("", DUMP_PREFIX_NONE, buf, sizeof(*info));
memset(info, 0, sizeof(*info));
return -EINVAL;
}
/* sanity check valid model */
if (info->model[0] != 'G' || info->model[1] != 'W') {
printf("EEPROM: I2C%d@0x%02x: Invalid Model in EEPROM\n", bus, slave);
print_hex_dump_bytes("", DUMP_PREFIX_NONE, buf, sizeof(*info));
memset(info, 0, sizeof(*info));
return -EINVAL;
}
return 0;
}
static const char *gsc_get_rst_cause(struct udevice *dev)
{
static char str[64];
static const char * const names[] = {
"VIN",
"PB",
"WDT",
"CPU",
"TEMP_L",
"TEMP_R",
"SLEEP",
"BOOT_WDT1",
"BOOT_WDT2",
"SOFT_PWR",
};
unsigned char reg;
/* reset cause */
str[0] = 0;
if (!dm_i2c_read(dev, GSC_SC_RST_CAUSE, ®, 1)) {
if (reg < ARRAY_SIZE(names))
sprintf(str, "%s", names[reg]);
else
sprintf(str, "0x%02x", reg);
}
/* thermal protection */
if (!dm_i2c_read(dev, GSC_SC_THERM_PROTECT, ®, 1)) {
strcat(str, " Thermal Protection ");
if (reg & BIT(0))
strcat(str, "Enabled");
else
strcat(str, "Disabled");
}
return str;
}
/* display hardware monitor ADC channels */
int gsc_hwmon(void)
{
const void *fdt = gd->fdt_blob;
struct udevice *dev;
int node, reg, mode, len, val, offset;
const char *label;
u8 buf[2];
int ret;
node = fdt_node_offset_by_compatible(fdt, -1, "gw,gsc-adc");
if (node <= 0)
return node;
/* probe device */
dev = gsc_get_dev(GSC_BUSNO, GSC_HWMON_ADDR);
if (!dev) {
puts("ERROR: Failed to probe GSC HWMON\n");
return -ENODEV;
}
/* iterate over hwmon nodes */
node = fdt_first_subnode(fdt, node);
while (node > 0) {
reg = fdtdec_get_int(fdt, node, "reg", -1);
mode = fdtdec_get_int(fdt, node, "gw,mode", -1);
offset = fdtdec_get_int(fdt, node, "gw,voltage-offset-microvolt", 0);
label = fdt_stringlist_get(fdt, node, "label", 0, NULL);
if ((reg == -1) || (mode == -1) || !label)
printf("invalid dt:%s\n", fdt_get_name(fdt, node, NULL));
memset(buf, 0, sizeof(buf));
ret = dm_i2c_read(dev, reg, buf, sizeof(buf));
if (ret) {
printf("i2c error: %d\n", ret);
continue;
}
val = buf[0] | buf[1] << 8;
if (val >= 0) {
const u32 *div;
int r[2];
switch (mode) {
case 0: /* temperature (C*10) */
if (val > 0x8000)
val -= 0xffff;
printf("%-8s: %d.%ldC\n", label, val / 10, abs(val % 10));
break;
case 1: /* prescaled voltage */
if (val != 0xffff)
printf("%-8s: %d.%03dV\n", label, val / 1000, val % 1000);
break;
case 2: /* scaled based on ref volt and resolution */
val *= 2500;
val /= 1 << 12;
/* apply pre-scaler voltage divider */
div = fdt_getprop(fdt, node, "gw,voltage-divider-ohms", &len);
if (div && (len == sizeof(uint32_t) * 2)) {
r[0] = fdt32_to_cpu(div[0]);
r[1] = fdt32_to_cpu(div[1]);
if (r[0] && r[1]) {
val *= (r[0] + r[1]);
val /= r[1];
}
}
/* adjust by offset */
val += (offset / 1000);
printf("%-8s: %d.%03dV\n", label, val / 1000, val % 1000);
break;
}
}
node = fdt_next_subnode(fdt, node);
}
return 0;
}
/* determine BOM revision from model */
int get_bom_rev(const char *str)
{
int rev_bom = 0;
int i;
for (i = strlen(str) - 1; i > 0; i--) {
if (str[i] == '-')
break;
if (str[i] >= '1' && str[i] <= '9') {
rev_bom = str[i] - '0';
break;
}
}
return rev_bom;
}
/* determine PCB revision from model */
char get_pcb_rev(const char *str)
{
char rev_pcb = 'A';
int i;
for (i = strlen(str) - 1; i > 0; i--) {
if (str[i] == '-')
break;
if (str[i] >= 'A') {
rev_pcb = str[i];
break;
}
}
return rev_pcb;
}
/*
* get dt name based on model and detail level:
*
* For boards that are a combination of a SoM plus a Baseboard:
* Venice SoM part numbers are GW70xx where xx is:
* 7000-7019: same PCB with som dt of '0x'
* 7020-7039: same PCB with som dt of '2x'
* 7040-7059: same PCB with som dt of '4x'
* 7060-7079: same PCB with som dt of '6x'
* 7080-7099: same PCB with som dt of '8x'
* Venice Baseboard part numbers are GW7xxx where xxx is:
* 7100-7199: same PCB with base dt of '71xx'
* 7200-7299: same PCB with base dt of '72xx'
* 7300-7399: same PCB with base dt of '73xx'
* 7400-7499: same PCB with base dt of '74xx'
* 7500-7599: same PCB with base dt of '75xx'
* 7600-7699: same PCB with base dt of '76xx'
* 7700-7799: same PCB with base dt of '77xx'
* 7800-7899: same PCB with base dt of '78xx'
* DT name is comprised of:
* gw<base dt>-<som dt>-[base-pcb-rev][base-bom-rev][som-pcb-rev][som-bom-rev]
*
* For board models from 7900-7999 each PCB is unique with its own dt:
* DT name is comprised:
* gw<model>-[pcb-rev][bom-rev]
*
*/
#define snprintfcat(dest, sz, fmt, ...) \
snprintf((dest) + strlen(dest), (sz) - strlen(dest), fmt, ##__VA_ARGS__)
const char *gsc_get_dtb_name(int level, char *buf, int sz)
{
const char *pre = "imx8mm-venice-gw";
int model, rev_pcb, rev_bom;
model = ((som_info.model[2] - '0') * 1000)
+ ((som_info.model[3] - '0') * 100)
+ ((som_info.model[4] - '0') * 10)
+ (som_info.model[5] - '0');
rev_pcb = tolower(get_pcb_rev(som_info.model));
rev_bom = get_bom_rev(som_info.model);
/* som + baseboard*/
if (base_info.model[0]) {
/* baseboard id: 7100-7199->71; 7200-7299->72; etc */
int base = ((base_info.model[2] - '0') * 10) + (base_info.model[3] - '0');
/* som id: 7000-7019->1; 7020-7039->2; etc */
int som = ((model % 100) / 20) * 2;
int rev_base_pcb = tolower(get_pcb_rev(base_info.model));
int rev_base_bom = get_bom_rev(base_info.model);
snprintf(buf, sz, "%s%2dxx-%dx", pre, base, som);
switch (level) {
case 0: /* full model (ie gw73xx-0x-a1a1) */
if (rev_base_bom)
snprintfcat(buf, sz, "-%c%d", rev_base_pcb, rev_base_bom);
else
snprintfcat(buf, sz, "-%c", rev_base_pcb);
if (rev_bom)
snprintfcat(buf, sz, "%c%d", rev_pcb, rev_bom);
else
snprintfcat(buf, sz, "%c", rev_pcb);
break;
case 1: /* don't care about SoM revision */
if (rev_base_bom)
snprintfcat(buf, sz, "-%c%d", rev_base_pcb, rev_base_bom);
else
snprintfcat(buf, sz, "-%c", rev_base_pcb);
snprintfcat(buf, sz, "xx");
break;
case 2: /* don't care about baseboard revision */
snprintfcat(buf, sz, "-xx");
if (rev_bom)
snprintfcat(buf, sz, "%c%d", rev_pcb, rev_bom);
else
snprintfcat(buf, sz, "%c", rev_pcb);
break;
case 3: /* don't care about SoM/baseboard revision */
break;
default:
return NULL;
}
} else {
snprintf(buf, sz, "%s%04d", pre, model);
switch (level) {
case 0: /* full model wth PCB and BOM revision first (ie gw7901-a1) */
if (rev_bom)
snprintfcat(buf, sz, "-%c%d", rev_pcb, rev_bom);
else
snprintfcat(buf, sz, "-%c", rev_pcb);
break;
case 1: /* don't care about BOM revision */
snprintfcat(buf, sz, "-%c", rev_pcb);
break;
case 2: /* don't care about PCB or BOM revision */
break;
default:
return NULL;
}
}
return buf;
}
static int gsc_read(void)
{
int ret;
ret = gsc_read_eeprom(GSC_BUSNO, GSC_EEPROM_ADDR, 1, &som_info);
if (ret) {
memset(&som_info, 0, sizeof(som_info));
return ret;
}
/* read optional baseboard EEPROM */
return gsc_read_eeprom(BASEBOARD_EEPROM_BUSNO, BASEBOARD_EEPROM_ADDR,
2, &base_info);
}
static int gsc_info(int verbose)
{
struct udevice *dev;
unsigned char buf[16];
char rev_pcb;
int rev_bom;
if (!base_info.model[0]) {
strcpy(venice_model, som_info.model);
printf("Model : %s\n", som_info.model);
printf("Serial : %d\n", som_info.serial);
printf("MFGDate : %02x-%02x-%02x%02x\n",
som_info.mfgdate[0], som_info.mfgdate[1],
som_info.mfgdate[2], som_info.mfgdate[3]);
} else {
sprintf(venice_model, "GW%c%c%c%c-%c%c-",
som_info.model[2], /* family */
base_info.model[3], /* baseboard */
base_info.model[4], base_info.model[5], /* subload of baseboard */
som_info.model[4], som_info.model[5]); /* last 2digits of SOM */
/* baseboard revision */
rev_pcb = get_pcb_rev(base_info.model);
rev_bom = get_bom_rev(base_info.model);
if (rev_bom)
sprintf(venice_model + strlen(venice_model), "%c%d", rev_pcb, rev_bom);
else
sprintf(venice_model + strlen(venice_model), "%c", rev_pcb);
/* som revision */
rev_pcb = get_pcb_rev(som_info.model);
rev_bom = get_bom_rev(som_info.model);
if (rev_bom)
sprintf(venice_model + strlen(venice_model), "%c%d", rev_pcb, rev_bom);
else
sprintf(venice_model + strlen(venice_model), "%c", rev_pcb);
if (verbose > 1) {
printf("SOM : %s %d %02x-%02x-%02x%02x\n",
som_info.model, som_info.serial,
som_info.mfgdate[0], som_info.mfgdate[1],
som_info.mfgdate[2], som_info.mfgdate[3]);
printf("BASE : %s %d %02x-%02x-%02x%02x\n",
base_info.model, base_info.serial,
base_info.mfgdate[0], base_info.mfgdate[1],
base_info.mfgdate[2], base_info.mfgdate[3]);
}
printf("Model : %s\n", venice_model);
printf("Serial : %d\n", som_info.serial);
printf("MFGDate : %02x-%02x-%02x%02x\n",
som_info.mfgdate[0], som_info.mfgdate[1],
som_info.mfgdate[2], som_info.mfgdate[3]);
}
/* Display RTC */
puts("RTC : ");
dev = gsc_get_dev(GSC_BUSNO, GSC_RTC_ADDR);
if (!dev) {
puts("Failed to probe GSC RTC\n");
} else {
dm_i2c_read(dev, 0, buf, 6);
printf("%d\n", buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24);
}
return 0;
}
int gsc_init(int quiet)
{
unsigned char buf[16];
struct udevice *dev;
int ret;
/*
* 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) {
/* probe device */
dev = gsc_get_dev(GSC_BUSNO, GSC_SC_ADDR);
if (dev)
break;
mdelay(1);
}
ret = dm_i2c_read(dev, 0, buf, sizeof(buf));
if (ret) {
puts("ERROR: Failed reading GSC\n");
return ret;
}
gsc_read();
/* banner */
if (!quiet) {
printf("GSC : v%d 0x%04x", buf[GSC_SC_FWVER],
buf[GSC_SC_FWCRC] | buf[GSC_SC_FWCRC + 1] << 8);
printf(" RST:%s", gsc_get_rst_cause(dev));
printf("\n");
gsc_info(1);
}
if (ret)
hang();
return ((16 << som_info.sdram_size) / 1024);
}
const char *gsc_get_model(void)
{
return venice_model;
}
#if !(IS_ENABLED(CONFIG_SPL_BUILD))
static int gsc_sleep(unsigned long secs)
{
unsigned char reg;
struct udevice *dev;
int ret;
/* probe device */
dev = gsc_get_dev(GSC_BUSNO, GSC_SC_ADDR);
if (!dev)
return -ENODEV;
printf("GSC Sleeping for %ld seconds\n", secs);
reg = (secs >> 24) & 0xff;
ret = dm_i2c_write(dev, 9, ®, 1);
if (ret)
goto err;
reg = (secs >> 16) & 0xff;
ret = dm_i2c_write(dev, 8, ®, 1);
if (ret)
goto err;
reg = (secs >> 8) & 0xff;
ret = dm_i2c_write(dev, 7, ®, 1);
if (ret)
goto err;
reg = secs & 0xff;
ret = dm_i2c_write(dev, 6, ®, 1);
if (ret)
goto err;
ret = dm_i2c_read(dev, GSC_SC_CTRL1, ®, 1);
if (ret)
goto err;
reg |= (1 << 2);
ret = dm_i2c_write(dev, GSC_SC_CTRL1, ®, 1);
if (ret)
goto err;
reg &= ~(1 << 2);
reg |= 0x3;
ret = dm_i2c_write(dev, GSC_SC_CTRL1, ®, 1);
if (ret)
goto err;
return 0;
err:
printf("i2c error\n");
return ret;
}
static int gsc_boot_wd_disable(void)
{
u8 reg;
struct udevice *dev;
int ret;
/* probe device */
dev = gsc_get_dev(GSC_BUSNO, GSC_SC_ADDR);
if (!dev)
return -ENODEV;
ret = dm_i2c_read(dev, GSC_SC_CTRL1, ®, 1);
if (ret)
goto err;
reg |= (1 << GSC_SC_CTRL1_WDDIS);
reg &= ~(1 << GSC_SC_CTRL1_BOOT_CHK);
ret = dm_i2c_write(dev, GSC_SC_CTRL1, ®, 1);
if (ret)
goto err;
puts("GSC : boot watchdog disabled\n");
return 0;
err:
printf("i2c error");
return ret;
}
static int do_gsc(struct cmd_tbl *cmdtp, int flag, int argc, char * const argv[])
{
if (argc < 2)
return gsc_info(2);
if (strcasecmp(argv[1], "sleep") == 0) {
if (argc < 3)
return CMD_RET_USAGE;
if (!gsc_sleep(dectoul(argv[2], NULL)))
return CMD_RET_SUCCESS;
} else if (strcasecmp(argv[1], "hwmon") == 0) {
if (!gsc_hwmon())
return CMD_RET_SUCCESS;
} else if (strcasecmp(argv[1], "wd-disable") == 0) {
if (!gsc_boot_wd_disable())
return CMD_RET_SUCCESS;
}
return CMD_RET_USAGE;
}
U_BOOT_CMD(gsc, 4, 1, do_gsc, "Gateworks System Controller",
"[sleep <secs>]|[hwmon]|[wd-disable]\n");
#endif
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