x86: coral: Show memory config and SKU ID on startup

Provide the model information through sysinfo so that it shows up on
boot. For memconfig 4 pins are provided, for 16 combinations. For SKU
ID there are two options:

   - two pins provided in a ternary arrangement, for 9 combinations.
   - reading from the EC

Add a binding doc and drop the unused #defines as well.

Example:

   U-Boot 2021.01-rc5

   CPU:   Intel(R) Celeron(R) CPU N3450 @ 1.10GHz
   DRAM:  3.9 GiB
   MMC:   sdmmc@1b,0: 1, emmc@1c,0: 2
   Video: 1024x768x32 @ b0000000
   Model: Google Coral (memconfig 5, SKU 3)

This depends on the GPIO series:

   http://patchwork.ozlabs.org/project/uboot/list/?series=228126

Signed-off-by: Simon Glass <sjg@chromium.org>

Acked-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/dts/chromebook_coral.dts

@@ -56,6 +56,17 @@
 		recovery-gpios = <&gpio_nw (-1) GPIO_ACTIVE_LOW>;
 		write-protect-gpios = <&gpio_nw GPIO_75 GPIO_ACTIVE_HIGH>;
 		phase-enforce-gpios = <&gpio_n GPIO_10 GPIO_ACTIVE_HIGH>;
+		memconfig-gpios = <&gpio_nw GPIO_101 GPIO_ACTIVE_HIGH
+			&gpio_nw GPIO_102 GPIO_ACTIVE_HIGH
+			&gpio_n GPIO_38 GPIO_ACTIVE_HIGH
+			&gpio_n GPIO_45 GPIO_ACTIVE_HIGH>;
+
+		/*
+		 * This is used for reef only:
+		 *
+		 * skuconfig-gpios = <&gpio_nw GPIO_16 GPIO_ACTIVE_HIGH
+		 *	&gpio_nw GPIO_17 GPIO_ACTIVE_HIGH>;
+		 */
 		smbios {
 			/* Type 1 table */
 			system {

board/google/chromebook_coral/coral.c

@@ -3,9 +3,12 @@
  * Copyright 2019 Google LLC
  */
 
+#define LOG_CATEGORY	UCLASS_SYSINFO
+
 #include <common.h>
 #include <bloblist.h>
 #include <command.h>
+#include <cros_ec.h>
 #include <dm.h>
 #include <log.h>
 #include <sysinfo.h>
@@ -15,6 +18,7 @@
 #include <asm/intel_gnvs.h>
 #include <asm/intel_pinctrl.h>
 #include <dm/acpi.h>
+#include <linux/delay.h>
 #include "variant_gpio.h"
 
 struct cros_gpio_info {
@@ -29,10 +33,125 @@ int arch_misc_init(void)
 	return 0;
 }
 
-/* This function is needed if CONFIG_CMDLINE is not enabled */
+static int get_memconfig(struct udevice *dev)
-int board_run_command(const char *cmdline)
 {
-	printf("No command line\n");
+	struct gpio_desc gpios[4];
+	int cfg;
+	int ret;
+
+	ret = gpio_request_list_by_name(dev, "memconfig-gpios", gpios,
+					ARRAY_SIZE(gpios),
+					GPIOD_IS_IN | GPIOD_PULL_UP);
+	if (ret < 0) {
+		log_debug("Cannot get GPIO list '%s' (%d)\n", dev->name, ret);
+		return ret;
+	}
+
+	/* Give the lines time to settle */
+	udelay(10);
+
+	ret = dm_gpio_get_values_as_int(gpios, ARRAY_SIZE(gpios));
+	if (ret < 0)
+		return log_msg_ret("get", ret);
+	cfg = ret;
+
+	ret = gpio_free_list(dev, gpios, ARRAY_SIZE(gpios));
+	if (ret)
+		return log_msg_ret("free", ret);
+
+	return cfg;
+}
+
+/**
+ * get_skuconfig() - Get the SKU number either from pins or the EC
+ *
+ * Two options are supported:
+ *     skuconfig-gpios - two pins in the device tree (tried first)
+ *     EC              - reading from the EC (backup)
+ *
+ * @dev: sysinfo device to use
+ * @return SKU ID, or -ve error if not found
+ */
+static int get_skuconfig(struct udevice *dev)
+{
+	struct gpio_desc gpios[2];
+	int cfg;
+	int ret;
+
+	ret = gpio_request_list_by_name(dev, "skuconfig-gpios", gpios,
+					ARRAY_SIZE(gpios),
+					GPIOD_IS_IN);
+	if (ret != ARRAY_SIZE(gpios)) {
+		struct udevice *cros_ec;
+
+		log_debug("Cannot get GPIO list '%s' (%d)\n", dev->name, ret);
+
+		/* Try the EC */
+		ret = uclass_first_device_err(UCLASS_CROS_EC, &cros_ec);
+		if (ret < 0) {
+			log_err("Cannot find EC for SKU details\n");
+			return log_msg_ret("sku", ret);
+		}
+		ret = cros_ec_get_sku_id(cros_ec);
+		if (ret < 0) {
+			log_err("Cannot read SKU details\n");
+			return log_msg_ret("sku", ret);
+		}
+
+		return ret;
+	}
+
+	ret = dm_gpio_get_values_as_int_base3(gpios, ARRAY_SIZE(gpios));
+	if (ret < 0)
+		return log_msg_ret("get", ret);
+	cfg = ret;
+
+	ret = gpio_free_list(dev, gpios, ARRAY_SIZE(gpios));
+	if (ret)
+		return log_msg_ret("free", ret);
+
+	return cfg;
+}
+
+static int coral_get_str(struct udevice *dev, int id, size_t size, char *val)
+{
+	int ret;
+
+	if (IS_ENABLED(CONFIG_SPL_BUILD))
+		return -ENOSYS;
+
+	switch (id) {
+	case SYSINFO_ID_SMBIOS_SYSTEM_VERSION:
+	case SYSINFO_ID_SMBIOS_BASEBOARD_VERSION: {
+		ret = get_skuconfig(dev);
+
+		if (ret < 0)
+			return ret;
+		if (size < 15)
+			return -ENOSPC;
+		sprintf(val, "rev%d", ret);
+		break;
+	}
+	case SYSINFO_ID_BOARD_MODEL: {
+		int mem_config, sku_config;
+		const char *model;
+
+		ret = get_memconfig(dev);
+		if (ret < 0)
+			log_warning("Unable to read memconfig (err=%d)\n", ret);
+		mem_config = ret;
+		ret = get_skuconfig(dev);
+		if (ret < 0)
+			log_warning("Unable to read skuconfig (err=%d)\n", ret);
+		sku_config = ret;
+		model = fdt_getprop(gd->fdt_blob, 0, "model", NULL);
+		snprintf(val, size, "%s (memconfig %d, SKU %d)", model,
+			 mem_config, sku_config);
+		break;
+	}
+	default:
+		return -ENOENT;
+	}
 
 	return 0;
 }
@@ -45,12 +164,15 @@ int chromeos_get_gpio(const struct udevice *dev, const char *prop,
 	int ret;
 
 	ret = gpio_request_by_name((struct udevice *)dev, prop, 0, &desc, 0);
-	if (ret == -ENOTBLK)
+	if (ret == -ENOTBLK) {
 		info->gpio_num = CROS_GPIO_VIRTUAL;
-	else if (ret)
+		log_debug("GPIO '%s' is virtual\n", prop);
+	} else if (ret) {
 		return log_msg_ret("gpio", ret);
-	else
+	} else {
 		info->gpio_num = desc.offset;
+		dm_gpio_free((struct udevice *)dev, &desc);
+	}
 	info->linux_name = dev_read_string(desc.dev, "linux-name");
 	if (!info->linux_name)
 		return log_msg_ret("linux-name", -ENOENT);
@@ -83,11 +205,11 @@ static int chromeos_acpi_gpio_generate(const struct udevice *dev,
 	ret = chromeos_get_gpio(dev, "write-protect-gpios", CROS_GPIO_WP,
 				&info[1]);
 	if (ret)
-		return log_msg_ret("rec", ret);
+		return log_msg_ret("wp", ret);
 	ret = chromeos_get_gpio(dev, "phase-enforce-gpios", CROS_GPIO_PE,
 				&info[2]);
 	if (ret)
-		return log_msg_ret("rec", ret);
+		return log_msg_ret("phase", ret);
 	acpigen_write_scope(ctx, "\\");
 	acpigen_write_name(ctx, "OIPG");
 	acpigen_write_package(ctx, count);
@@ -147,6 +269,7 @@ struct acpi_ops coral_acpi_ops = {
 };
 
 struct sysinfo_ops coral_sysinfo_ops = {
+	.get_str	= coral_get_str,
 };
 
 #if !CONFIG_IS_ENABLED(OF_PLATDATA)

board/google/chromebook_coral/variant_gpio.h

@@ -34,12 +34,6 @@
 /* Determine if board is in final shipping mode. */
 #define GPIO_SHIP_MODE	GPIO_10
 
-/*  Memory SKU GPIOs. */
-#define MEM_CONFIG3	GPIO_45
-#define MEM_CONFIG2	GPIO_38
-#define MEM_CONFIG1	GPIO_102
-#define MEM_CONFIG0	GPIO_101
-
 /* DMIC_CONFIG_PIN: High for 1-DMIC and low for 4-DMIC's */
 #define DMIC_CONFIG_PIN	GPIO_17
 

doc/device-tree-bindings/sysinfo/google,coral.txt

@@ -0,0 +1,37 @@
+Google Coral sysinfo information
+================================
+
+This binding allows information about the board to be described. It includes
+the SMBIOS binding as well.
+
+Required properties:
+
+  - compatible: "google,coral"
+  - recovery-gpios: GPIO to use for recovery button (-1 if none)
+  - wite-protect-gpios: GPIO to use for write-protect screw
+  - phase-enforce-gpios: GPIO to indicate the board is in final ship mode
+  - memconfig-gpios: 4 GPIOs to use to read memory config (as base2 int)
+
+Optional properties:
+  - skuconfig-gpios: 2 GPIOs to use to read SKU ID. If not present, the
+       Chromium OS EC SKU_ID is used instead
+
+Example:
+
+board: board {
+	compatible = "google,coral";
+	recovery-gpios = <&gpio_nw (-1) GPIO_ACTIVE_LOW>;
+	write-protect-gpios = <&gpio_nw GPIO_75 GPIO_ACTIVE_HIGH>;
+	phase-enforce-gpios = <&gpio_n GPIO_10 GPIO_ACTIVE_HIGH>;
+	memconfig-gpios = <&gpio_nw GPIO_101 GPIO_ACTIVE_HIGH
+		&gpio_nw GPIO_102 GPIO_ACTIVE_HIGH
+		&gpio_n GPIO_38 GPIO_ACTIVE_HIGH
+		&gpio_n GPIO_45 GPIO_ACTIVE_HIGH>;
+
+	/*
+	 * This is used for reef only:
+	 *
+	 * skuconfig-gpios = <&gpio_nw GPIO_16 GPIO_ACTIVE_HIGH
+	 *	&gpio_nw GPIO_17 GPIO_ACTIVE_HIGH>;
+	 */
+ };