[FFmpeg-devel] [PATCH] Disabled mipsdspr1 under 74kc cpu and disabled all mips hardware acceleration by default.

Nedeljko Babic Nedeljko.Babic at imgtec.com
Wed Mar 25 10:40:25 CET 2015

>From: Shivraj Patil <shivraj.patil at imgtec.com>
> configure | 6 ++++++
> 1 file changed, 6 insertions(+)
>diff --git a/configure b/configure
>index 4827a4d..1a08347 100755
>--- a/configure
>+++ b/configure
>@@ -3839,6 +3839,12 @@ elif enabled mips; then
>         ;;
>         74kc)
>             disable mipsfpu
>+            disable mipsdspr1
>+        ;;

DSP rev 1 should not be disabled for this architecture.
74kc architecture is backward compatible and it supports both dsp rev 2
and dsp rev1.

>+        *)
>+            disable mipsfpu
>+            disable mipsdspr1
>+            disable mipsdspr2
>         ;;
>     esac

The options for mips were created in a similar way as for all the other supported architectures:
All optimizations are enabled by default and for every group of optimizations 
there is a switch to disable it.

That means that the "*" case cannot be used as above.
If all the optimizations are disabled for "*" case, than that would mean that 
all optimizations will be disabled for any architecture that is not in the case 
list even if that architecture supports some (or all) of it.

Even worse, there would not be a way to enable any optimization for those 
architectures as there is no appropriate enable option.

For example, 74Kf architecture is basically the same as 74Kc with addition 
of FPU and it is not in the case list.
With "*" case like this all optimizations would be disabled for 74Kf although 
it supports all of them.


- Nedeljko

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