Hi Gregory,
Gregory Fong <[email protected]> writes:
> Hi all,
>
> In arch/powerpc/sysdev/mpic.c , it looks like IRQ_TYPE_EDGE_BOTH is
> handled the same way as IRQ_TYPE_EDGE_FALLING:
>
> static unsigned int mpic_type_to_vecpri(struct mpic *mpic, unsigned int type)
> {
> /* Now convert sense value */
> switch(type & IRQ_TYPE_SENSE_MASK) {
> case IRQ_TYPE_EDGE_RISING:
> return MPIC_INFO(VECPRI_SENSE_EDGE) |
> MPIC_INFO(VECPRI_POLARITY_POSITIVE);
> case IRQ_TYPE_EDGE_FALLING:
> case IRQ_TYPE_EDGE_BOTH:
> return MPIC_INFO(VECPRI_SENSE_EDGE) |
> MPIC_INFO(VECPRI_POLARITY_NEGATIVE);
> case IRQ_TYPE_LEVEL_HIGH:
> return MPIC_INFO(VECPRI_SENSE_LEVEL) |
> MPIC_INFO(VECPRI_POLARITY_POSITIVE);
> case IRQ_TYPE_LEVEL_LOW:
> default:
> return MPIC_INFO(VECPRI_SENSE_LEVEL) |
> MPIC_INFO(VECPRI_POLARITY_NEGATIVE);
> }
> }
>
> If IRQ_TYPE_EDGE_BOTH is unsupported, shouldn't we be returning an
> error, instead of silently setting to use IRQ_TYPE_EDGE_FALLING?
> Something like the following (sorry if the diff wraps weirdly, on
> webmail at the moment):
I don't know this code so I asked Ben and he said something like
"PowerMacs never use BOTH, so it hasn't mattered, but Freescale machines
might".
So if you want to send a proper signed-off patch, and confirm that all
the callers can handle the error properly, then we can merge it.
cheers
> ----8<----
> diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
> index b9aac95..5867ea2 100644
> --- a/arch/powerpc/sysdev/mpic.c
> +++ b/arch/powerpc/sysdev/mpic.c
> @@ -876,6 +876,9 @@ int mpic_set_irq_type(struct irq_data *d, unsigned
> int flow_type)
> if (src >= mpic->num_sources)
> return -EINVAL;
>
> + if (flow_type & IRQ_TYPE_SENSE_MASK == IRQ_TYPE_EDGE_BOTH)
> + return -EINVAL;
> +
> vold = mpic_irq_read(src, MPIC_INFO(IRQ_VECTOR_PRI));
>
> /* We don't support "none" type */
> ---->8----
>
> Thanks,
> Gregory
On 08/31/2017 01:52 AM, Michael Ellerman wrote:
> Hi Gregory,
>
> Gregory Fong <[email protected]> writes:
>> Hi all,
>>
>> In arch/powerpc/sysdev/mpic.c , it looks like IRQ_TYPE_EDGE_BOTH is
>> handled the same way as IRQ_TYPE_EDGE_FALLING:
>>
>> static unsigned int mpic_type_to_vecpri(struct mpic *mpic, unsigned int type)
>> {
>> /* Now convert sense value */
>> switch(type & IRQ_TYPE_SENSE_MASK) {
>> case IRQ_TYPE_EDGE_RISING:
>> return MPIC_INFO(VECPRI_SENSE_EDGE) |
>> MPIC_INFO(VECPRI_POLARITY_POSITIVE);
>> case IRQ_TYPE_EDGE_FALLING:
>> case IRQ_TYPE_EDGE_BOTH:
>> return MPIC_INFO(VECPRI_SENSE_EDGE) |
>> MPIC_INFO(VECPRI_POLARITY_NEGATIVE);
>> case IRQ_TYPE_LEVEL_HIGH:
>> return MPIC_INFO(VECPRI_SENSE_LEVEL) |
>> MPIC_INFO(VECPRI_POLARITY_POSITIVE);
>> case IRQ_TYPE_LEVEL_LOW:
>> default:
>> return MPIC_INFO(VECPRI_SENSE_LEVEL) |
>> MPIC_INFO(VECPRI_POLARITY_NEGATIVE);
>> }
>> }
>>
>> If IRQ_TYPE_EDGE_BOTH is unsupported, shouldn't we be returning an
>> error, instead of silently setting to use IRQ_TYPE_EDGE_FALLING?
>> Something like the following (sorry if the diff wraps weirdly, on
>> webmail at the moment):
>
> I don't know this code so I asked Ben and he said something like
> "PowerMacs never use BOTH, so it hasn't mattered, but Freescale machines
> might".
IIRC, the mpic in freescale MPICs the interrupts are either low or high,
so not both. There's a bit which controls the interrupt polarity which
selects if the interrupt triggers on high-to-low or low-to-high.
So i guess it doesn't matter on freescale machines too.
---
Best Regards, Laurentiu