MIPS: ath79: provide driver for Atheros ART partition

this partition contains calibration data for WiFi and
some board specific data, like MAC address.

For now we care only about MAC.

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 113 insertions, 0 deletions

diff --git a/arch/mips/mach-ath79/Makefile b/arch/mips/mach-ath79/Makefile
index 3772daebad..b827b363cf 100644
--- a/arch/mips/mach-ath79/Makefile
+++ b/arch/mips/mach-ath79/Makefile
@@ -1,2 +1,3 @@
 obj-y += reset.o
 obj-y += bbu.o
+obj-y += art.o
diff --git a/arch/mips/mach-ath79/art.c b/arch/mips/mach-ath79/art.c
new file mode 100644
index 0000000000..984d087363
--- /dev/null
+++ b/arch/mips/mach-ath79/art.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.
+/*
+ * Copyright (c) 2018 Oleksij Rempel <linux@rempel-privat.de>
+ */
+
+#include <common.h>
+#include <fcntl.h>
+#include <init.h>
+#include <libfile.h>
+#include <net.h>
+#include <unistd.h>
+
+#define AR93000_EPPROM_OFFSET	0x1000
+
+struct ar9300_eeprom {
+	u8 eeprom_version;
+	u8 template_version;
+	u8 mac_addr[6];
+};
+
+static int art_set_mac(struct device_d *dev, struct ar9300_eeprom *eeprom)
+{
+	struct device_node *node = dev->device_node;
+	struct device_node *rnode;
+
+	if (!node)
+		return -ENOENT;
+
+	rnode = of_parse_phandle_from(node, NULL,
+				     "barebox,provide-mac-address", 0);
+	if (!rnode)
+		return -ENOENT;
+
+	of_eth_register_ethaddr(rnode, &eeprom->mac_addr[0]);
+
+	return 0;
+}
+
+static int art_read_mac(struct device_d *dev, const char *file)
+{
+	int fd, rbytes;
+	struct ar9300_eeprom eeprom;
+
+	fd = open_and_lseek(file, O_RDONLY, AR93000_EPPROM_OFFSET);
+	if (fd < 0) {
+		dev_err(dev, "Failed to open eeprom path %s %d\n",
+		       file, fd);
+		return fd;
+	}
+
+	rbytes = read_full(fd, &eeprom, sizeof(eeprom));
+	close(fd);
+	if (rbytes < sizeof(eeprom)) {
+		dev_err(dev, "Failed to read %s\n", file);
+		return rbytes < 0 ? rbytes : -EIO;
+	}
+
+	dev_dbg(dev, "ART version: %x.%x\n",
+		 eeprom.eeprom_version, eeprom.template_version);
+	dev_dbg(dev, "mac: %02x:%02x:%02x:%02x:%02x:%02x\n",
+	       eeprom.mac_addr[0],
+	       eeprom.mac_addr[1],
+	       eeprom.mac_addr[2],
+	       eeprom.mac_addr[3],
+	       eeprom.mac_addr[4],
+	       eeprom.mac_addr[5]);
+
+	if (!is_valid_ether_addr(&eeprom.mac_addr[0])) {
+		dev_err(dev, "bad MAC addr\n");
+		return -EILSEQ;
+	}
+
+	return art_set_mac(dev, &eeprom);
+}
+
+static int art_probe(struct device_d *dev)
+{
+	char *path;
+	int ret;
+
+	dev_dbg(dev, "found ART partition\n");
+
+	ret = of_find_path(dev->device_node, "device-path", &path, 0);
+	if (ret) {
+		dev_err(dev, "can't find path\n");
+		return ret;
+	}
+
+	return art_read_mac(dev, path);
+}
+
+static struct of_device_id art_dt_ids[] = {
+	{
+		.compatible = "qca,art",
+	}, {
+		/* sentinel */
+	}
+};
+
+static struct driver_d art_driver = {
+	.name		= "qca-art",
+	.probe		= art_probe,
+	.of_compatible	= art_dt_ids,
+};
+
+static int art_of_driver_init(void)
+{
+	platform_driver_register(&art_driver);
+
+	return 0;
+}
+late_initcall(art_of_driver_init);