[0/3] hw: aspeed_gpio: Model new interface for the AST2600

Message

Andrew Jeffery Feb. 7, 2022, 3:04 p.m. UTC

Hello,

This series adds support for a new register interface supported by the
Aspeed GPIO controller, present in at least the AST2600.

The new interface is a single register implementing an indirect command
protocol that allows us to manipulate up to (at least) 208 GPIOs. This
makes it possible to write very simple drivers for e.g. u-boot and
jettison the need for the tedious data model required to deal with the
old register layout.

I've lightly tested the device consistency under Linux. The Linux
driver is implemented in terms of the old interface, so data model
consistency can be tested one way by poking the driver using the
libgpiod tools and then the other using devmem to drive the new
interface.

Please review!

Andrew

Andrew Jeffery (3):
  hw: aspeed_gpio: Cleanup stray semicolon after switch
  hw: aspeed_gpio: Split GPIOSet handling from accessors
  hw: aspeed_gpio: Support the AST2600's indexed register interface

 hw/gpio/aspeed_gpio.c         | 305 ++++++++++++++++++++++++++++------
 include/hw/gpio/aspeed_gpio.h |   3 +
 2 files changed, 261 insertions(+), 47 deletions(-)

Comments

Andrew Jeffery Feb. 9, 2022, 11:09 a.m. UTC | #1

On Tue, 8 Feb 2022, at 01:34, Andrew Jeffery wrote:
> Hello,
>
> This series adds support for a new register interface supported by the
> Aspeed GPIO controller, present in at least the AST2600.
>
> The new interface is a single register implementing an indirect command
> protocol that allows us to manipulate up to (at least) 208 GPIOs. This
> makes it possible to write very simple drivers for e.g. u-boot and
> jettison the need for the tedious data model required to deal with the
> old register layout.
>
> I've lightly tested the device consistency under Linux. The Linux
> driver is implemented in terms of the old interface, so data model
> consistency can be tested one way by poking the driver using the
> libgpiod tools and then the other using devmem to drive the new
> interface.
>
> Please review!

Naturally further testing revealed some quirks that require further 
enhancements to the modelling.

Hold off on doing anything with this series for the moment.

Cheers,

Andrew