On 3/25/11, Peter Maydell <peter.mayd...@linaro.org> wrote:
> On 24 March 2011 22:07, Dmitry Eremin-Solenikov <dbarysh...@gmail.com>
> wrote:
>> Currently target-arm/ assumes at least ARMv5 core. Add support for
>> handling also ARMv4/ARMv4T. This changes the following instructions:
>
> Mostly looks good; comments below.
>
>> @@ -161,6 +179,8 @@ static void cpu_reset_model_id(CPUARMState *env,
>> uint32_t id)
>> break;
>> case ARM_CPUID_TI915T:
>> case ARM_CPUID_TI925T:
>> + set_feature(env, ARM_FEATURE_V4T);
>> + set_feature(env, ARM_FEATURE_V5);
>> set_feature(env, ARM_FEATURE_OMAPCP);
>> env->cp15.c0_cpuid = ARM_CPUID_TI925T; /* Depends on wiring. */
>> env->cp15.c0_cachetype = 0x5109149;
>
> As far as I can tell from google these are based on the ARM9TDMI
> which means they're ARMv4T and so shouldn't have the V5 feature set.
> (You can legitimately feel disgruntled that whoever added these didn't
> do the v4T stuff properly :-))
Oops. According to cpuid they indeed are V4T.
>
>> @@ -6129,6 +6131,7 @@ static void disas_arm_insn(CPUState * env,
>> DisasContext *s)
>> }
>> }
>> /* Otherwise PLD; v5TE+ */
>> + ARCH(5);
>> return;
>> }
>> if (((insn & 0x0f70f000) == 0x0450f000) ||
>
> Rather than adding ARCH() lines here and in some of the following
> hunks it would be simpler to change the
>
> if (cond == 0xf){
> /* Unconditional instructions. */
>
> to:
>
> if (cond == 0xf) {
> /* In ARMv3 and v4 the NV condition is UNPREDICTABLE; we
> * choose to UNDEF. In ARMv5 and above the space is used
> * for miscellaneous unconditional instructions.
> */
> ARCH(5);
Ack. I just wanted to be insn-by-insn clear, rather than disabling
full blocks.
> Some bits that are missing from this patch:
>
> You need to guard the Thumb BKPT and BLX decodes
> with ARCH(5) as they're not in v4T.
... and fix the V4T PUSH containing PC.
> The CPSR Q bit needs to RAZ/WI on v4 and v4T.
Can we assume (maybe temporarily) that all v5 are also v5TE?
It seems it's currently done so, and I don't want to be too intrusive.
I'll need to dig more into this...
--
With best wishes
Dmitry
