[PATCH 2/3] nvmem: brcm_nvram: add .read_post_process() for MACs

From: Rafał Miłecki
Date: Thu Apr 06 2023 - 07:09:04 EST


From: Rafał Miłecki <rafal@xxxxxxxxxx>

1. Parse ASCII MAC format into byte based
2. Calculate relative addresses based on index argument

Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
drivers/nvmem/Kconfig | 1 +
drivers/nvmem/brcm_nvram.c | 28 ++++++++++++++++++++++++++++
2 files changed, 29 insertions(+)

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index b291b27048c7..688b70ba4826 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -55,6 +55,7 @@ config NVMEM_BRCM_NVRAM
tristate "Broadcom's NVRAM support"
depends on ARCH_BCM_5301X || COMPILE_TEST
depends on HAS_IOMEM
+ select GENERIC_NET_UTILS
help
This driver provides support for Broadcom's NVRAM that can be accessed
using I/O mapping.
diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c
index 39aa27942f28..4567c597c87f 100644
--- a/drivers/nvmem/brcm_nvram.c
+++ b/drivers/nvmem/brcm_nvram.c
@@ -4,6 +4,8 @@
*/

#include <linux/bcm47xx_nvram.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
#include <linux/io.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
@@ -42,6 +44,25 @@ static int brcm_nvram_read(void *context, unsigned int offset, void *val,
return 0;
}

+static int brcm_nvram_read_post_process_macaddr(void *context, const char *id, int index,
+ unsigned int offset, void *buf, size_t bytes)
+{
+ u8 mac[ETH_ALEN];
+
+ if (bytes != 3 * ETH_ALEN - 1)
+ return -EINVAL;
+
+ if (!mac_pton(buf, mac))
+ return -EINVAL;
+
+ if (index)
+ eth_addr_add(mac, index);
+
+ ether_addr_copy(buf, mac);
+
+ return 0;
+}
+
static int brcm_nvram_add_cells(struct brcm_nvram *priv, uint8_t *data,
size_t len)
{
@@ -75,6 +96,13 @@ static int brcm_nvram_add_cells(struct brcm_nvram *priv, uint8_t *data,
priv->cells[idx].offset = value - (char *)data;
priv->cells[idx].bytes = strlen(value);
priv->cells[idx].np = of_get_child_by_name(dev->of_node, priv->cells[idx].name);
+ if (!strcmp(var, "et0macaddr") ||
+ !strcmp(var, "et1macaddr") ||
+ !strcmp(var, "et2macaddr")) {
+ priv->cells[idx].raw_len = strlen(value);
+ priv->cells[idx].bytes = ETH_ALEN;
+ priv->cells[idx].read_post_process = brcm_nvram_read_post_process_macaddr;
+ }
}

return 0;
--
2.34.1