Re: [PATCH v3 3/5] fsi: master-ast-cf: Add new FSI master using Aspeed ColdFire
From: Joel Stanley
Date: Thu Jul 12 2018 - 03:53:42 EST
On 12 July 2018 at 13:48, Benjamin Herrenschmidt
<benh@xxxxxxxxxxxxxxxxxxx> wrote:
> The Aspeed AST2x00 can contain a ColdFire v1 coprocessor which
> is currently unused on OpenPower systems.
>
> This adds an alternative to the fsi-master-gpio driver that
> uses that coprocessor instead of bit banging from the ARM
> core itself. The end result is about 4 times faster.
>
> The firmware for the coprocessor and its source code can be
> found at https://github.com/ozbenh/cf-fsi and is system specific.
>
> Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/fsi/Kconfig | 9 +
> drivers/fsi/Makefile | 1 +
> drivers/fsi/cf-fsi-fw.h | 157 +++
> drivers/fsi/fsi-master-ast-cf.c | 1438 ++++++++++++++++++++++
> include/trace/events/fsi_master_ast_cf.h | 150 +++
> 5 files changed, 1755 insertions(+)
> create mode 100644 drivers/fsi/cf-fsi-fw.h
> create mode 100644 drivers/fsi/fsi-master-ast-cf.c
> create mode 100644 include/trace/events/fsi_master_ast_cf.h
>
> diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
> index 322cec393cf2..e0220d1e1357 100644
> --- a/drivers/fsi/Kconfig
> +++ b/drivers/fsi/Kconfig
> @@ -27,6 +27,15 @@ config FSI_MASTER_HUB
> allow chaining of FSI links to an arbitrary depth. This allows for
> a high target device fanout.
>
> +config FSI_MASTER_AST_CF
> + tristate "FSI master based on Aspeed ColdFire coprocessor"
> + depends on GPIOLIB
> + depends on GPIO_ASPEED
> + ---help---
> + This option enables a FSI master using the AST2400 and AST2500 GPIO
> + lines driven by the internal ColdFire coprocessor. This requires
> + the corresponding machine specific ColdFire firmware to be available.
The "machine specific" part isn't true anymore, is it?
I gave this a spin on a palmetto and it appeared to work fine for me.
Tested-by: Joel Stanley <joel@xxxxxxxxx>