diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2016-07-29 11:47:03 +0200 |
|---|---|---|
| committer | Hans de Goede <hdegoede@redhat.com> | 2016-07-31 21:45:39 +0200 |
| commit | 3f8ea3b06eaf7c9e2456058bcbde32461e73aeb7 (patch) | |
| tree | 2b364c088976a23569134f593b2c47e89e2a5b27 /board/sunxi | |
| parent | 97322c3e074d49b1e2c6d98c7e69e5da3093636f (diff) | |
sunxi: On newer SoCs use words 1-3 instead of just word 3 from the SID
It seems that bytes 13-14 of the SID / bytes 1-2 from word 3 of the SID
are always 0 on H3 making it a poor candidate to use as source for the
serialnr / mac-address, and the other non constant words (1 and 2) also
have quite a few bits which are the same for some boards,
This commits switches to using the crc32 of words 1 - 3 to get a
more unique value for the mac-address / serialnr.
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Corentin LABBE <clabbe.montjoie@gmail.com>
Cc: Amit Singh Tomar <amittomer25@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
Diffstat (limited to 'board/sunxi')
| -rw-r--r-- | board/sunxi/board.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/board/sunxi/board.c b/board/sunxi/board.c index ef3fe26d69..209fb1cfd8 100644 --- a/board/sunxi/board.c +++ b/board/sunxi/board.c @@ -27,6 +27,7 @@ #endif #include <asm/gpio.h> #include <asm/io.h> +#include <crc.h> #include <environment.h> #include <libfdt.h> #include <nand.h> @@ -622,7 +623,24 @@ static void setup_environment(const void *fdt) int i, ret; ret = sunxi_get_sid(sid); - if (ret == 0 && sid[0] != 0 && sid[3] != 0) { + if (ret == 0 && sid[0] != 0) { + /* + * The single words 1 - 3 of the SID have quite a few bits + * which are the same on many models, so we take a crc32 + * of all 3 words, to get a more unique value. + * + * Note we only do this on newer SoCs as we cannot change + * the algorithm on older SoCs since those have been using + * fixed mac-addresses based on only using word 3 for a + * long time and changing a fixed mac-address with an + * u-boot update is not good. + */ +#if !defined(CONFIG_MACH_SUN4I) && !defined(CONFIG_MACH_SUN5I) && \ + !defined(CONFIG_MACH_SUN6I) && !defined(CONFIG_MACH_SUN7I) && \ + !defined(CONFIG_MACH_SUN8I_A23) && !defined(CONFIG_MACH_SUN8I_A33) + sid[3] = crc32(0, (unsigned char *)&sid[1], 12); +#endif + /* Ensure the NIC specific bytes of the mac are not all 0 */ if ((sid[3] & 0xffffff) == 0) sid[3] |= 0x800000; |