diff options
Diffstat (limited to 'pkgs/patches-linux-5.15/682-of_net-add-mac-address-increment-support.patch')
| -rw-r--r-- | pkgs/patches-linux-5.15/682-of_net-add-mac-address-increment-support.patch | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/pkgs/patches-linux-5.15/682-of_net-add-mac-address-increment-support.patch b/pkgs/patches-linux-5.15/682-of_net-add-mac-address-increment-support.patch new file mode 100644 index 0000000..fe6fadd --- /dev/null +++ b/pkgs/patches-linux-5.15/682-of_net-add-mac-address-increment-support.patch @@ -0,0 +1,89 @@ +From 844c273286f328acf0dab5fbd5d864366b4904dc Mon Sep 17 00:00:00 2001 +From: Ansuel Smith <ansuelsmth@gmail.com> +Date: Tue, 30 Mar 2021 18:21:14 +0200 +Subject: [PATCH] of_net: add mac-address-increment support + +Lots of embedded devices use the mac-address of other interface +extracted from nvmem cells and increments it by one or two. Add two +bindings to integrate this and directly use the right mac-address for +the interface. Some example are some routers that use the gmac +mac-address stored in the art partition and increments it by one for the +wifi. mac-address-increment-byte bindings is used to tell what byte of +the mac-address has to be increased (if not defined the last byte is +increased) and mac-address-increment tells how much the byte decided +early has to be increased. + +Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com> +--- + net/core/of_net.c | 43 +++++++++++++++++++++++++++++++++++++++---- + 1 file changed, 39 insertions(+), 4 deletions(-) + +--- a/net/core/of_net.c ++++ b/net/core/of_net.c +@@ -119,27 +119,62 @@ static int of_get_mac_addr_nvmem(struct + * this case, the real MAC is in 'local-mac-address', and 'mac-address' exists + * but is all zeros. + * ++ * DT can tell the system to increment the mac-address after is extracted by ++ * using: ++ * - mac-address-increment-byte to decide what byte to increase ++ * (if not defined is increased the last byte) ++ * - mac-address-increment to decide how much to increase. The value WILL ++ * overflow to other bytes if the increment is over 255 or the total ++ * increment will exceed 255 of the current byte. ++ * (example 00:01:02:03:04:ff + 1 == 00:01:02:03:05:00) ++ * (example 00:01:02:03:04:fe + 5 == 00:01:02:03:05:03) ++ * + * Return: 0 on success and errno in case of error. + */ + int of_get_mac_address(struct device_node *np, u8 *addr) + { ++ u32 inc_idx, mac_inc, mac_val; + int ret; + ++ /* Check first if the increment byte is present and valid. ++ * If not set assume to increment the last byte if found. ++ */ ++ if (of_property_read_u32(np, "mac-address-increment-byte", &inc_idx)) ++ inc_idx = 5; ++ if (inc_idx < 3 || inc_idx > 5) ++ return -EINVAL; ++ + if (!np) + return -ENODEV; + + ret = of_get_mac_addr(np, "mac-address", addr); + if (!ret) +- return 0; ++ goto found; + + ret = of_get_mac_addr(np, "local-mac-address", addr); + if (!ret) +- return 0; ++ goto found; + + ret = of_get_mac_addr(np, "address", addr); + if (!ret) +- return 0; ++ goto found; ++ ++ ret = of_get_mac_addr_nvmem(np, addr); ++ if (ret) ++ return ret; ++ ++found: ++ if (!of_property_read_u32(np, "mac-address-increment", &mac_inc)) { ++ /* Convert to a contiguous value */ ++ mac_val = (addr[3] << 16) + (addr[4] << 8) + addr[5]; ++ mac_val += mac_inc << 8 * (5-inc_idx); ++ ++ /* Apply the incremented value handling overflow case */ ++ addr[3] = (mac_val >> 16) & 0xff; ++ addr[4] = (mac_val >> 8) & 0xff; ++ addr[5] = (mac_val >> 0) & 0xff; ++ } + +- return of_get_mac_addr_nvmem(np, addr); ++ return ret; + } + EXPORT_SYMBOL(of_get_mac_address); |