Re: [PATCH] MIPS: remove support for trap and emulate KVM

[Philippe Mathieu-Daudé]

On 18/12/22 01:06, Paolo Bonzini wrote:
> This support was limited to the Malta board, drop it.
> I do not have a machine that can run VZ KVM, so I am assuming
> that it works for -M malta as well.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   docs/about/deprecated.rst       |  9 -------
>   docs/about/removed-features.rst |  9 +++++++
>   hw/mips/malta.c                 | 44 ++++-----------------------------
>   target/mips/cpu.c               |  7 +-----
>   target/mips/cpu.h               |  2 --
>   target/mips/kvm.c               | 11 +--------
>   target/mips/sysemu/addr.c       | 17 -------------
>   target/mips/sysemu/physaddr.c   | 13 ----------
>   8 files changed, 16 insertions(+), 96 deletions(-)


> diff --git a/target/mips/cpu.c b/target/mips/cpu.c
> index 7a565466cb3f..065a9cd10ec9 100644
> --- a/target/mips/cpu.c
> +++ b/target/mips/cpu.c
> @@ -290,12 +290,7 @@ static void mips_cpu_reset(DeviceState *dev)
>       env->tlb->tlb_in_use = env->tlb->nb_tlb;
>       env->CP0_Wired = 0;
>       env->CP0_GlobalNumber = (cs->cpu_index & 0xFF) << CP0GN_VPId;
> -    env->CP0_EBase = (cs->cpu_index & 0x3FF);
> -    if (mips_um_ksegs_enabled()) {
> -        env->CP0_EBase |= 0x40000000;
> -    } else {
> -        env->CP0_EBase |= (int32_t)0x80000000;
> -    }
> +    env->CP0_EBase = (cs->cpu_index & 0x3FF) | (int32_t)0x80000000;

Pre-existing, but maybe clearer as:

       env->CP0_EBase = KSEG0_BASE | (cs->cpu_index & 0x3FF);

>       if (env->CP0_Config3 & (1 << CP0C3_CMGCR)) {
>           env->CP0_CMGCRBase = 0x1fbf8000 >> 4;
>       }
> diff --git a/target/mips/cpu.h b/target/mips/cpu.h
> index 0a085643a3f1..3411cbc37825 100644
> --- a/target/mips/cpu.h
> +++ b/target/mips/cpu.h
> @@ -1299,8 +1299,6 @@ uint64_t cpu_mips_phys_to_kseg0(void *opaque, uint64_t 
> addr);
>   uint64_t cpu_mips_kvm_um_phys_to_kseg0(void *opaque, uint64_t addr);

cpu_mips_kvm_um_phys_to_kseg0() is removed ...

>   uint64_t cpu_mips_kseg1_to_phys(void *opaque, uint64_t addr);
>   uint64_t cpu_mips_phys_to_kseg1(void *opaque, uint64_t addr);
> -bool mips_um_ksegs_enabled(void);
> -void mips_um_ksegs_enable(void);
>   
>   #if !defined(CONFIG_USER_ONLY)

> diff --git a/target/mips/sysemu/addr.c b/target/mips/sysemu/addr.c
> index 86f1c129c9f4..4f025be44a1d 100644
> --- a/target/mips/sysemu/addr.c
> +++ b/target/mips/sysemu/addr.c
> @@ -23,8 +23,6 @@
>   #include "qemu/osdep.h"
>   #include "cpu.h"

> -uint64_t cpu_mips_kvm_um_phys_to_kseg0(void *opaque, uint64_t addr)
> -{
> -    return addr | 0x40000000ll;
> -}

... here.