meta-facebook: yosemite4: NIC present read fail

Return from setup_nic() when devmem fails instead of interpreting its
empty output as an active-low presence signal. Continue checking the
remaining NICs.

Use 32-bit accesses for the word-aligned ASPEED GPIO registers.
The previous byte accesses cause SIGBUS under QEMU and can trigger
spurious endpoint setup and core dump collection.

```
root@yosemite4:~# devmem 0x1e780088 8
Bus error                  (core dumped) devmem 0x1e780088 8
root@yosemite4:~# devmem 0x1e780088 32
0x01000F00
```

```
Oct 16 07:51:10 yosemite4 systemd-coredump[20015]: [🡕] Process 20013 (devmem) of user 0 dumped core.
```

QEMU's ASPEED GPIO model explicitly accepts only four-byte accesse [1].

```c
static const MemoryRegionOps aspeed_gpio_ops = {
    .read       = aspeed_gpio_read,
    .write      = aspeed_gpio_write,
    .endianness = DEVICE_LITTLE_ENDIAN,
    .valid.min_access_size = 4,
    .valid.max_access_size = 4,
};
```

The upstream Linux ASPEED GPIO driver also reads GPIO values with
ioread32() in aspeed_gpio_get(). This supports using word accesses,
but does not establish that byte accesses are forbidden on silicon[2].

References:
[1] https://github.com/qemu/qemu/blob/master/hw/gpio/aspeed_gpio.c#L1417-L1423
[2] https://github.com/torvalds/linux/blob/v6.12/drivers/gpio/gpio-aspeed.c

Change-Id: I339af15ddb866f5d1e77277793b489282e792c3a
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>

0 files changed, 0 insertions, 0 deletions