GPIOs

[John Watlington]

I'm proposing a new GPIO map for XO-1.5 B3 and beyond.

The changes are:
- Moved the control signals for the internal and external SD ports
  and the WLAN around to match new port assignment.

- The power control for the internal SD port (MSD_PWROFF) is provided
  through a separate GPIO2 (instead of the faulty default output,  
SDIO2PWOFF).
  As there is an external pullup on this signal, there is no need to
  enable the (default off) internal pullup.    GPIO2 has been tested
  by Via to remain powered and glitch-free in states S0/S3.

- For B2 prototypes, I am proposing the use of GPIO2 as an ECO'd power
control signal for the WLAN.

- The DCONIRQ line has been moved (again).  On B2, the interrupt
  input chosen is synchronized by the RTC clock, preventing reliable
  detection of DCON interrupts (which are one video line in duration).
  This time, it is connected to GPIO12, which is only powered in S0
  but can generate SCI/SMI interrupts and is not "owned" by ACPI.

- The EC/CPU interrupt will also be routed to another pin capable
  of generating SCI/SMI interrupts that is not "owned" by ACPI at the
  request of pgf.   It is routed to GPIO11, which is only powered in S0.
  This pin will be diode isolated from the other interrupt input  
(powered
  in S3.)   Unfortunately, I can't find another interrupt input not  
owned by
  ACPI that is powered in S3.

- The HDD_LED# signal (yet to be supported) has been moved to GPO4
   to free up GPIO11.

Cheers,
wad

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