diff options
| author | Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk> | 2021-06-25 07:53:58 +0100 |
|---|---|---|
| committer | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2021-07-02 17:35:08 +0200 |
| commit | 846feac2ae1d1dab08c0048807ce802a256179fd (patch) | |
| tree | 61bbe426e00f3c35b82d5d3c05ead161feee63ed /hw/m68k/q800.c | |
| parent | db1ffc32dd0d32ef476c00637efc888ecea8466c (diff) | |
hw/m68k/q800: fix PROM checksum and MAC address storage
The checksum used by MacOS to validate the PROM content is an exclusive-OR
rather than a sum over the corresponding bytes. In addition the MAC address
must be stored in bit-reversed format as indicated in comments in Linux's
macsonic.c.
With the PROM contents fixed MacOS starts to probe the device registers
when AppleTalk is enabled in the Control Panel.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Tested-by: Finn Thain <fthain@linux-m68k.org>
Message-Id: <20210625065401.30170-8-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Diffstat (limited to 'hw/m68k/q800.c')
| -rw-r--r-- | hw/m68k/q800.c | 7 |
1 files changed, 2 insertions, 5 deletions
diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c index 491f283a17..6817c8b5d1 100644 --- a/hw/m68k/q800.c +++ b/hw/m68k/q800.c @@ -334,11 +334,8 @@ static void q800_init(MachineState *machine) prom = memory_region_get_ram_ptr(dp8393x_prom); checksum = 0; for (i = 0; i < 6; i++) { - prom[i] = nd_table[0].macaddr.a[i]; - checksum += prom[i]; - if (checksum > 0xff) { - checksum = (checksum + 1) & 0xff; - } + prom[i] = bitrev8(nd_table[0].macaddr.a[i]); + checksum ^= prom[i]; } prom[7] = 0xff - checksum; |