Re: [PATCH] target/xtensa: enable all coprocessors for linux-user

From: Laurent Vivier <laurent@vivier.eu>
To: Max Filippov <jcmvbkbc@gmail.com>, qemu-devel@nongnu.org
Subject: Re: [PATCH] target/xtensa: enable all coprocessors for linux-user
Date: Mon, 26 Oct 2020 12:07:41 +0100	[thread overview]
Message-ID: <cf165fff-1812-68f1-8d4f-d1db88ef260a@vivier.eu> (raw)
In-Reply-To: <20200829104758.22337-1-jcmvbkbc@gmail.com>

Le 29/08/2020 à 12:47, Max Filippov a écrit :
> Linux userspace always sees coprocessors as enabled. CPENABLE register
> and coprocessor exceptions are used internally by the kernel to manage
> lazy coprocessor context switch. None of it is needed for linux-user.
> Always enable all coprocessors for user emulation.
> 
> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
> ---
>  target/xtensa/cpu.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/target/xtensa/cpu.c b/target/xtensa/cpu.c
> index 6a033e778c95..88a32268a18b 100644
> --- a/target/xtensa/cpu.c
> +++ b/target/xtensa/cpu.c
> @@ -93,6 +93,7 @@ static void xtensa_cpu_reset(DeviceState *dev)
>          !xtensa_abi_call0()) {
>          env->sregs[PS] |= PS_WOE;
>      }
> +    env->sregs[CPENABLE] = 0xff;
>  #endif
>      env->sregs[VECBASE] = env->config->vecbase;
>      env->sregs[IBREAKENABLE] = 0;
> 

Applied to my linux-user-for-5.2 branch.

Thanks,
Laurent