Re: [PATCH v15 15/23] cpu: tcg_ops: move to tcg-cpu-ops.h, keep a pointer in CPUClass

[Philippe Mathieu-Daudé]

On 2/3/21 3:41 PM, Claudio Fontana wrote:
> On 2/3/21 2:23 PM, Alex Bennée wrote:
>> Claudio Fontana <cfontana@suse.de> writes:
...
>>  /*
>> modified   target/arm/cpu.c
>> @@ -2248,7 +2248,7 @@ static gchar *arm_gdb_arch_name(CPUState *cs)
>>   * NB: cannot be const, as some elements are changed for specific
>>   * arm cpu classes.
>>   */
>> -static struct TCGCPUOps arm_tcg_ops = {
>> +static const struct TCGCPUOps arm_tcg_ops = {
>>      .initialize = arm_translate_init,
>>      .synchronize_from_tb = arm_cpu_synchronize_from_tb,
>>      .cpu_exec_interrupt = arm_cpu_exec_interrupt,
>> --8<---------------cut here---------------end--------------->8---
>>
>> This does later break MIPS jazz:
>>
>> p/hw_mips_jazz.c.o -c ../../hw/mips/jazz.c
>> ../../hw/mips/jazz.c: In function ‘mips_jazz_init’:
>> ../../hw/mips/jazz.c:216:40: error: assignment of member 
>> ‘do_transaction_failed’ in read-only object
>>      cc->tcg_ops->do_transaction_failed = mips_jazz_do_transaction_failed;
>>
>> which...
>>
>> <snip>
>>>  
>>> +#ifdef CONFIG_TCG
>>> +#include "hw/core/tcg-cpu-ops.h"
>>> +/*
>>> + * NB: cannot be const, as some elements are changed for specific
>>> + * mips hardware (see hw/mips/jazz.c).
>>> + */
>>
>> does have a valid comment. So guess keep it as static and just don't
>> claim ARM hacks around with it or find a more elegant solution for the
>> Jazz hack (I'm not sure there is one).
> 
> Yep, the ARM claim was true when I started looking at this, but now it's not 
> anymore after the changes.
> 
> However, I haven't found a way to remove the mips jazz hack.
> 
> Maybe Philippe knows?

We need to test the real behavior on real hardware.

Eventually writing the test and asking on linux-mips@vger.kernel.org
if someone can run it?