Add new function eth_random_enetaddr() to generate a locally administered ethernet address.
Signed-off-by: Michael Walle michael@walle.cc Cc: Joe Hershberger joe.hershberger@gmail.com --- include/net.h | 17 +++++++++++++++++ net/eth.c | 22 ++++++++++++++++++++++ 2 files changed, 39 insertions(+), 0 deletions(-)
diff --git a/include/net.h b/include/net.h index ee11f82..f6aeba2 100644 --- a/include/net.h +++ b/include/net.h @@ -118,6 +118,23 @@ extern int eth_setenv_enetaddr(char *name, const uchar *enetaddr); extern int eth_getenv_enetaddr_by_index(const char *base_name, int index, uchar *enetaddr);
+#ifdef CONFIG_RANDOM_MACADDR +/* + * The u-boot policy does not allow hardcoded ethernet addresses. Under the + * following circumstances a random generated address is allowed: + * - in emergency cases, where you need a working network connection to set + * the ethernet address. + * Eg. you want a rescue boot and don't have a serial port to access the + * CLI to set environment variables. + * + * In these cases, we generate a random locally administered ethernet address. + * + * Args: + * enetaddr - returns 6 byte hardware address + */ +extern void eth_random_enetaddr(uchar *enetaddr); +#endif + extern int usb_eth_initialize(bd_t *bi); extern int eth_init(bd_t *bis); /* Initialize the device */ extern int eth_send(volatile void *packet, int length); /* Send a packet */ diff --git a/net/eth.c b/net/eth.c index 3eeb908..c9f05d8 100644 --- a/net/eth.c +++ b/net/eth.c @@ -70,6 +70,28 @@ static int eth_mac_skip(int index) return ((skip_state = getenv(enetvar)) != NULL); }
+#ifdef CONFIG_RANDOM_MACADDR +void eth_random_enetaddr(uchar *enetaddr) +{ + uint32_t rval; + + srand(get_timer(0)); + + rval = rand(); + enetaddr[0] = rval & 0xff; + enetaddr[1] = (rval >> 8) & 0xff; + enetaddr[2] = (rval >> 16) & 0xff; + + rval = rand(); + enetaddr[3] = rval & 0xff; + enetaddr[4] = (rval >> 8) & 0xff; + enetaddr[5] = (rval >> 16) & 0xff; + + /* make sure it's local and unicast */ + enetaddr[0] = (enetaddr[0] | 0x02) & ~0x01; +} +#endif + /* * CPU and board-specific Ethernet initializations. Aliased function * signals caller to move on