sysinfo: rcar3: Add Renesas R-Car Gen3 sysinfo driver

The Renesas R-Car Gen3 development kits contain board ID EEPROM.
This driver parses out the board ID and revision out of that
EEPROM and exports it e.g. for the board-info print on boot.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Sean Anderson <sean.anderson@seco.com>
Cc: Simon Glass <sjg@chromium.org>

3 files changed, 205 insertions, 0 deletions

diff --git a/drivers/sysinfo/Kconfig b/drivers/sysinfo/Kconfig
index 381dcd8..e35f7cb 100644
--- a/drivers/sysinfo/Kconfig
+++ b/drivers/sysinfo/Kconfig
@@ -17,6 +17,13 @@ config SYSINFO_GAZERBEAM
 	help
 	  Support querying device information for the gdsys Gazerbeam board.
 
+config SYSINFO_RCAR3
+	bool "Enable sysinfo driver for the Renesas R-Car Gen3"
+	depends on RCAR_GEN3 && I2C_EEPROM
+	default y if RCAR_GEN3
+	help
+	  Support querying SoC version information for Renesas R-Car Gen3.
+
 config SYSINFO_SANDBOX
 	bool "Enable sysinfo driver for the Sandbox board"
 	help
diff --git a/drivers/sysinfo/Makefile b/drivers/sysinfo/Makefile
index d9f708b..680dde7 100644
--- a/drivers/sysinfo/Makefile
+++ b/drivers/sysinfo/Makefile
@@ -5,5 +5,6 @@
 obj-y += sysinfo-uclass.o
 obj-$(CONFIG_SYSINFO_GAZERBEAM) += gazerbeam.o
 obj-$(CONFIG_SYSINFO_GPIO) += gpio.o
+obj-$(CONFIG_SYSINFO_RCAR3) += rcar3.o
 obj-$(CONFIG_SYSINFO_SANDBOX) += sandbox.o
 obj-$(CONFIG_SYSINFO_SMBIOS) += smbios.o
diff --git a/drivers/sysinfo/rcar3.c b/drivers/sysinfo/rcar3.c
new file mode 100644
index 0000000..c2f4ddf
--- /dev/null
+++ b/drivers/sysinfo/rcar3.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2021 Marek Vasut <marek.vasut+renesas@gmail.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <i2c_eeprom.h>
+#include <log.h>
+#include <sysinfo.h>
+
+#define BOARD_CODE_MASK		0xF8
+#define BOARD_REV_MASK		0x07
+#define BOARD_CODE_SHIFT	0x03
+
+#define BOARD_SALVATOR_X	0x0
+#define BOARD_KRIEK		0x1
+#define BOARD_STARTER_KIT	0x2
+#define BOARD_SALVATOR_XS	0x4
+#define BOARD_EBISU		0x8
+#define BOARD_STARTER_KIT_PRE	0xB
+#define BOARD_EBISU_4D		0xD
+#define BOARD_DRAAK		0xE
+#define BOARD_EAGLE		0xF
+
+/**
+ * struct sysinfo_rcar_priv - sysinfo private data
+ * @boardname: board model and revision
+ * @val: board ID value from eeprom
+ */
+struct sysinfo_rcar_priv {
+	char	boardmodel[64];
+	u8	val;
+};
+
+static int sysinfo_rcar_detect(struct udevice *dev)
+{
+	struct sysinfo_rcar_priv *priv = dev_get_priv(dev);
+
+	return priv->val == 0xff;
+}
+
+static int sysinfo_rcar_get_str(struct udevice *dev, int id, size_t size, char *val)
+{
+	struct sysinfo_rcar_priv *priv = dev_get_priv(dev);
+
+	switch (id) {
+	case SYSINFO_ID_BOARD_MODEL:
+		strncpy(val, priv->boardmodel, size);
+		val[size - 1] = '\0';
+		return 0;
+	default:
+		return -EINVAL;
+	};
+}
+
+static const struct sysinfo_ops sysinfo_rcar_ops = {
+	.detect = sysinfo_rcar_detect,
+	.get_str = sysinfo_rcar_get_str,
+};
+
+static void sysinfo_rcar_parse(struct sysinfo_rcar_priv *priv)
+{
+	const u8 board_id = (priv->val & BOARD_CODE_MASK) >> BOARD_CODE_SHIFT;
+	const u8 board_rev = priv->val & BOARD_REV_MASK;
+	bool salvator_xs = false;
+	bool ebisu_4d = false;
+	char rev_major = '?';
+	char rev_minor = '?';
+
+	switch (board_id) {
+	case BOARD_SALVATOR_XS:
+		salvator_xs = true;
+		fallthrough;
+	case BOARD_SALVATOR_X:
+		if (!(board_rev & ~1)) { /* Only rev 0 and 1 is valid */
+			rev_major = '1';
+			rev_minor = '0' + (board_rev & BIT(0));
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Salvator-X%s board rev %c.%c",
+			 salvator_xs ? "S" : "", rev_major, rev_minor);
+		return;
+	case BOARD_STARTER_KIT:
+		if (!(board_rev & ~1)) { /* Only rev 0 and 1 is valid */
+			rev_major = (board_rev & BIT(0)) ? '3' : '1';
+			rev_minor = '0';
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Starter Kit board rev %c.%c",
+			 rev_major, rev_minor);
+		return;
+	case BOARD_STARTER_KIT_PRE:
+		if (!(board_rev & ~3)) { /* Only rev 0..3 is valid */
+			rev_major = (board_rev & BIT(1)) ? '2' : '1';
+			rev_minor = (board_rev == 3) ? '1' : '0';
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Starter Kit Premier board rev %c.%c",
+			 rev_major, rev_minor);
+		return;
+	case BOARD_EAGLE:
+		if (!board_rev) { /* Only rev 0 is valid */
+			rev_major = '1';
+			rev_minor = '0';
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Eagle board rev %c.%c",
+			 rev_major, rev_minor);
+		return;
+	case BOARD_EBISU_4D:
+		ebisu_4d = true;
+		fallthrough;
+	case BOARD_EBISU:
+		if (!board_rev) { /* Only rev 0 is valid */
+			rev_major = '1';
+			rev_minor = '0';
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Ebisu%s board rev %c.%c",
+			 ebisu_4d ? "-4D" : "", rev_major, rev_minor);
+		return;
+	case BOARD_DRAAK:
+		if (!board_rev) { /* Only rev 0 is valid */
+			rev_major = '1';
+			rev_minor = '0';
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Draak board rev %c.%c",
+			 rev_major, rev_minor);
+		return;
+	case BOARD_KRIEK:
+		if (!board_rev) { /* Only rev 0 is valid */
+			rev_major = '1';
+			rev_minor = '0';
+		}
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas Kriek board rev %c.%c",
+			 rev_major, rev_minor);
+		return;
+	default:
+		snprintf(priv->boardmodel, sizeof(priv->boardmodel),
+			 "Renesas -Unknown- board rev ?.?");
+		priv->val = 0xff;
+		return;
+	}
+}
+
+static int sysinfo_rcar_probe(struct udevice *dev)
+{
+	struct sysinfo_rcar_priv *priv = dev_get_priv(dev);
+	struct ofnode_phandle_args phandle_args;
+	struct udevice *i2c_eeprom;
+	u32 offset;
+	int ret;
+
+	offset = dev_read_u32_default(dev, "offset", 0x70);
+
+	ret = dev_read_phandle_with_args(dev, "i2c-eeprom", NULL,
+					 0, 0, &phandle_args);
+	if (ret) {
+		debug("%s: i2c-eeprom backing device not specified\n",
+		      dev->name);
+		return ret;
+	}
+
+	ret = uclass_get_device_by_ofnode(UCLASS_I2C_EEPROM, phandle_args.node,
+					  &i2c_eeprom);
+	if (ret) {
+		debug("%s: could not get backing device\n", dev->name);
+		return ret;
+	}
+
+	ret = i2c_eeprom_read(i2c_eeprom, offset, &priv->val, 1);
+	if (ret < 0) {
+		debug("%s: read failed\n", __func__);
+		return -EIO;
+	}
+
+	sysinfo_rcar_parse(priv);
+
+	return 0;
+}
+
+static const struct udevice_id sysinfo_rcar_ids[] = {
+	{ .compatible = "renesas,rcar-sysinfo" },
+	{ /* sentinel */ }
+};
+
+U_BOOT_DRIVER(sysinfo_rcar) = {
+	.name           = "sysinfo_rcar",
+	.id             = UCLASS_SYSINFO,
+	.of_match       = sysinfo_rcar_ids,
+	.ops		= &sysinfo_rcar_ops,
+	.priv_auto	= sizeof(struct sysinfo_rcar_priv),
+	.probe          = sysinfo_rcar_probe,
+};