Re: [PATCH v3 0/6] Add loongarch32 mode for loongarch64-softmmu

[Richard Henderson <richard.henderson@linaro.org>]

On 8/7/23 02:44, Jiajie Chen wrote:
> This patch series allow qemu-system-loongarch64 to emulate a LoongArch32
> machine. A mode enum is added to CPUArchState to select LA32 or LA64 at
> runtime. A new CPU model is added for loongarch32. Initial GDB support
> is added.
> 
> Changes since v2:
> 
> - Fix typo in previous commit
> - Fix VPPN width in TLBEHI/TLBREHI
> 
> Changes since v1:
> 
> - No longer create a separate qemu-system-loongarch32 executable, but
>    allow user to run loongarch32 emulation using qemu-system-loongarch64
> - Add loongarch32 cpu support for virt machine
> 
> Full changes:
> 
> Jiajie Chen (6):
>    target/loongarch: Add loongarch32 mode for loongarch64-softmmu
>    target/loongarch: Add loongarch32 cpu la132
>    target/loongarch: Add GDB support for loongarch32 mode
>    target/loongarch: Support LoongArch32 TLB entry
>    target/loongarch: Support LoongArch32 DMW
>    target/loongarch: Support LoongArch32 VPPN

There are changes missing for the translator.

All of the doubleword (D) instructions must be rejected in LA32 mode.

Virtual addresses must be zero-extended from 32 bits in 32-bit addressing mode.

I see a note about VA32L1/VA32L2/VA32L3 in CSR.MISC enabling 32-bit address mode for LA64. 
  You would want to implement this with a HW_FLAGS bit which indicates to the translator 
whether 32-bit addressing is enabled in the current mode.  This would always be true for 
LA32, and from MISC for the current priv level for LA64.

There are changes to BL, JIRL and PCADD* to sign-extend in 32-bit address mode.

What happened to the PWCH adjustment from v1?


r~