[PATCH v3 1/1] mfd: intel-m10-bmc: expose mac address and count

From: Russ Weight
Date: Tue Jan 05 2021 - 17:56:53 EST


Create two sysfs entries for exposing the MAC address
and count from the MAX10 BMC register space. The MAC
address is the first in a sequential block of MAC addresses
reserved for the FPGA card. The MAC count is the number
of MAC addresses in the reserved block.

Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
---
v3:
- Updated Date and KernelVersion in ABI documentation
v2:
- Updated the documentation for the mac_address and mac_count
sysfs nodes to clarify their usage.
- Changed sysfs _show() functions to use sysfs_emit() instead
of sprintf.
---
.../ABI/testing/sysfs-driver-intel-m10-bmc | 21 +++++++++
drivers/mfd/intel-m10-bmc.c | 43 +++++++++++++++++++
include/linux/mfd/intel-m10-bmc.h | 9 ++++
3 files changed, 73 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc
index 979a2d62513f..9773925138af 100644
--- a/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc
+++ b/Documentation/ABI/testing/sysfs-driver-intel-m10-bmc
@@ -13,3 +13,24 @@ Contact: Xu Yilun <yilun.xu@xxxxxxxxx>
Description: Read only. Returns the firmware version of Intel MAX10
BMC chip.
Format: "0x%x".
+
+What: /sys/bus/spi/devices/.../mac_address
+Date: January 2021
+KernelVersion: 5.12
+Contact: Russ Weight <russell.h.weight@xxxxxxxxx>
+Description: Read only. Returns the first MAC address in a block
+ of sequential MAC addresses assigned to the board
+ that is managed by the Intel MAX10 BMC. It is stored in
+ FLASH storage and is mirrored in the MAX10 BMC register
+ space.
+ Format: "%02x:%02x:%02x:%02x:%02x:%02x".
+
+What: /sys/bus/spi/devices/.../mac_count
+Date: January 2021
+KernelVersion: 5.12
+Contact: Russ Weight <russell.h.weight@xxxxxxxxx>
+Description: Read only. Returns the number of sequential MAC
+ addresses assigned to the board managed by the Intel
+ MAX10 BMC. This value is stored in FLASH and is mirrored
+ in the MAX10 BMC register space.
+ Format: "%u".
diff --git a/drivers/mfd/intel-m10-bmc.c b/drivers/mfd/intel-m10-bmc.c
index b84579b7b4f0..751c0ecf95d6 100644
--- a/drivers/mfd/intel-m10-bmc.c
+++ b/drivers/mfd/intel-m10-bmc.c
@@ -60,9 +60,52 @@ static ssize_t bmcfw_version_show(struct device *dev,
}
static DEVICE_ATTR_RO(bmcfw_version);

+static ssize_t mac_address_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct intel_m10bmc *max10 = dev_get_drvdata(dev);
+ unsigned int macaddr1, macaddr2;
+ int ret;
+
+ ret = m10bmc_sys_read(max10, M10BMC_MACADDR1, &macaddr1);
+ if (ret)
+ return ret;
+
+ ret = m10bmc_sys_read(max10, M10BMC_MACADDR2, &macaddr2);
+ if (ret)
+ return ret;
+
+ return sysfs_emit(buf, "%02x:%02x:%02x:%02x:%02x:%02x\n",
+ (u8)FIELD_GET(M10BMC_MAC_BYTE1, macaddr1),
+ (u8)FIELD_GET(M10BMC_MAC_BYTE2, macaddr1),
+ (u8)FIELD_GET(M10BMC_MAC_BYTE3, macaddr1),
+ (u8)FIELD_GET(M10BMC_MAC_BYTE4, macaddr1),
+ (u8)FIELD_GET(M10BMC_MAC_BYTE5, macaddr2),
+ (u8)FIELD_GET(M10BMC_MAC_BYTE6, macaddr2));
+}
+static DEVICE_ATTR_RO(mac_address);
+
+static ssize_t mac_count_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct intel_m10bmc *max10 = dev_get_drvdata(dev);
+ unsigned int macaddr2;
+ int ret;
+
+ ret = m10bmc_sys_read(max10, M10BMC_MACADDR2, &macaddr2);
+ if (ret)
+ return ret;
+
+ return sysfs_emit(buf, "%u\n",
+ (u8)FIELD_GET(M10BMC_MAC_COUNT, macaddr2));
+}
+static DEVICE_ATTR_RO(mac_count);
+
static struct attribute *m10bmc_attrs[] = {
&dev_attr_bmc_version.attr,
&dev_attr_bmcfw_version.attr,
+ &dev_attr_mac_address.attr,
+ &dev_attr_mac_count.attr,
NULL,
};
ATTRIBUTE_GROUPS(m10bmc);
diff --git a/include/linux/mfd/intel-m10-bmc.h b/include/linux/mfd/intel-m10-bmc.h
index c8ef2f1654a4..2279e34f0814 100644
--- a/include/linux/mfd/intel-m10-bmc.h
+++ b/include/linux/mfd/intel-m10-bmc.h
@@ -15,6 +15,15 @@

/* Register offset of system registers */
#define NIOS2_FW_VERSION 0x0
+#define M10BMC_MACADDR1 0x10
+#define M10BMC_MAC_BYTE4 GENMASK(7, 0)
+#define M10BMC_MAC_BYTE3 GENMASK(15, 8)
+#define M10BMC_MAC_BYTE2 GENMASK(23, 16)
+#define M10BMC_MAC_BYTE1 GENMASK(31, 24)
+#define M10BMC_MACADDR2 0x14
+#define M10BMC_MAC_BYTE6 GENMASK(7, 0)
+#define M10BMC_MAC_BYTE5 GENMASK(15, 8)
+#define M10BMC_MAC_COUNT GENMASK(23, 16)
#define M10BMC_TEST_REG 0x3c
#define M10BMC_BUILD_VER 0x68
#define M10BMC_VER_MAJOR_MSK GENMASK(23, 16)
--
2.25.1