[Mesa-dev] [PATCH 17/24] i965/cnl: Implement new pipe control workaround

[Jason Ekstrand]

On Fri, May 12, 2017 at 4:38 PM, Anuj Phogat <anuj.phogat at gmail.com> wrote:

> From: Ben Widawsky <benjamin.widawsky at intel.com>
>
> GEN10 requires flushing all previous pipe controls before issuing a render
> target cache flush. The docs seem to fairly explicitly say this is gen10
> only.
>
> V2 (by Anuj): Use flags & PIPE_CONTROL_RENDER_TARGET_FLUSH check. (Ilia)
>               Use recursive call to brw_emit_pipe_control_flush().
>
> Signed-off-by: Ben Widawsky <benjamin.widawsky at intel.com>
> Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
> ---
>  src/mesa/drivers/dri/i965/brw_pipe_control.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_pipe_control.c
> b/src/mesa/drivers/dri/i965/brw_pipe_control.c
> index f4ede2d..ecf2fac 100644
> --- a/src/mesa/drivers/dri/i965/brw_pipe_control.c
> +++ b/src/mesa/drivers/dri/i965/brw_pipe_control.c
> @@ -128,6 +128,17 @@ brw_emit_pipe_control_flush(struct brw_context *brw,
> uint32_t flags)
>           brw_emit_pipe_control_flush(brw, 0);
>        }
>
> +      if (brw->gen == 10 && (flags & PIPE_CONTROL_RENDER_TARGET_FLUSH)) {
> +        /* Hardware workaround: CNL
> +         *
> +         * "Before sending a PIPE_CONTROL command with bit 12 set, SW
> +         * must issue another PIPE_CONTROL with Render Target Cache
> +         * Flush Enable (bit 12) = 0 and Pipe Control Flush Enable
> +         * (bit 7) = 1."
>

A more specific spec citation would be good.  Maybe something like:

>From the "Gen10 Workarounds" page:

In any case, the workaround looks correct although the docs say it only
applies to A0 stepping.  Is this still even needed?


> +         */
> +         brw_emit_pipe_control_flush(brw, PIPE_CONTROL_FLUSH_ENABLE);
> +      }
> +
>        BEGIN_BATCH(6);
>        OUT_BATCH(_3DSTATE_PIPE_CONTROL | (6 - 2));
>        OUT_BATCH(flags);
> --
> 2.9.3
>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/mesa-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20170602/945ca354/attachment.html>