mb/asus/f2a85-m_pro: Enable UART A in Super I/O

Currently, the serial console does not work.

With the serial port enabled in the vendor firmware, `superiotool` outputs
the global control register values below.

    Found Nuvoton NCT6779D (id=0xc562) at 0x2e
    Register dump:
    idx 10 11 13 14 1a 1b 1c 1d  20 21 22 24 25 26 27 28  2a 2b 2c 2f
    val ff ff ff ff 3a 28 00 10  c5 62 df 04 00 00 10 00  48 20 00 01
    def ff ff 00 00 30 70 10 00  c5 62 ff 04 00 MM 00 00  c0 00 01 MM

UART A needs to be enabled in CR 0x2a by clearing bit 7. Do this by
selecting the Super I/O Kconfig symbol `SUPERIO_NUVOTON_COMMON_COM_A`.
This changes the default value 0xc0 to 0x40.

Note, due configuring the system as legacy free with
`HUDSON_LEGACY_FREE=y`, AGESA in romstage disables the LPC controller in
`FchInitResetLpcProgram()`.

    coreboot-4.12-3417-g192b9576fe Tue Oct 20 09:15:53 UTC 2020 romstage starting (log level: 7)...
    APIC 00: CPU Family_Model = 00610f31

    APIC 00: ** Enter AmdInitReset [00020007]
    Fch OEM config in INIT RESET

`AmdInitReset() returned AGESA_SUCCESS` is not transmitted anymore. Only
when coreboot enables the LPC controller again in ramstage, serial output
continues.

    PCI: 00:14.4 bridge ctrl <- 0013
    PCI: 00:14.4 cmd <- 00
    PCI: 00:14.5 cmd <- 02
    PCI: 00:15.0 bridge ctrl <- 0013
    PCI: 00:15.0 cmd <- 00
    PCI: 00:15.1 bridge ctrl <- 0013
    […]
    done.
    BS: BS_DEV_ENABLE run times (exec / console): 0 / 30 ms
    Initializing devices...
    CPU_CLUSTER: 0 init
    […]

Note, due to incorrect Super I/O configuration in the devicetree, the boot
hangs in `PCI: 00:14.3 init` when doing `outb(0, DMA1_RESET_REG)`. This
will be fixed in follow-up commits.

TEST=Receive (some) coreboot log messages over the serial console.
Change-Id: I0aa367316f274ed0dd5964ba5ed045b9aeaccf8d
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/39371
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

0 files changed, 0 insertions, 0 deletions