Re: [RFC PATCH v2 07/22] target/arm: Add support for NMI event state

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

On 2/21/24 10:10, Richard Henderson wrote:
> On 2/21/24 03:08, Jinjie Ruan via wrote:
>> The NMI exception state include whether the interrupt with super priority
>> is IRQ or FIQ, so add a nmi_is_irq flag in CPUARMState to distinguish it.
>>
>> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
>> ---
>>   target/arm/cpu.h    | 2 ++
>>   target/arm/helper.c | 9 +++++++++
>>   2 files changed, 11 insertions(+)
>>
>> diff --git a/target/arm/cpu.h b/target/arm/cpu.h
>> index 5257343bcb..051e589e19 100644
>> --- a/target/arm/cpu.h
>> +++ b/target/arm/cpu.h
>> @@ -603,6 +603,8 @@ typedef struct CPUArchState {
>>       /* State of our input IRQ/FIQ/VIRQ/VFIQ lines */
>>       uint32_t irq_line_state;
>> +    bool nmi_is_irq;
> 
> Why would you need to add this to CPUARMState?
> This has the appearance of requiring only a local variable.
> But it is hard to tell since you do not set it within this patch at all.

According to Arm GIC section 4.6.3 Interrupt superpriority, NMI is always IRQ, never FIQ, 
so this is never required.


r~