Re: [PATCH v2 01/12] irqchip/gic: Rework gic_configure_irq to take the full ICFGR base

From: Marc Zyngier
Date: Mon Aug 19 2019 - 10:53:16 EST


On 19/08/2019 15:26, Zenghui Yu wrote:
> Hi Marc,
>
> On 2019/8/6 18:01, Marc Zyngier wrote:
>> gic_configure_irq is currently passed the (re)distributor address,
>> to which it applies an a fixed offset to get to the configuration
>> registers. This offset is constant across all GICs, or rather it was
>> until to v3.1...
>>
>> An easy way out is for the individual drivers to pass the base
>> address of the configuration register for the considered interrupt.
>> At the same time, move part of the error handling back to the
>> individual drivers, as things are about to change on that front.
>>
>> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
>> ---
>> drivers/irqchip/irq-gic-common.c | 14 +++++---------
>> drivers/irqchip/irq-gic-v3.c | 11 ++++++++++-
>> drivers/irqchip/irq-gic.c | 10 +++++++++-
>> drivers/irqchip/irq-hip04.c | 7 ++++++-
>> 4 files changed, 30 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-common.c
>> index b0a8215a13fc..6900b6f0921c 100644
>> --- a/drivers/irqchip/irq-gic-common.c
>> +++ b/drivers/irqchip/irq-gic-common.c
>> @@ -63,7 +63,7 @@ int gic_configure_irq(unsigned int irq, unsigned int type,
>> * for "irq", depending on "type".
>> */
>> raw_spin_lock_irqsave(&irq_controller_lock, flags);
>> - val = oldval = readl_relaxed(base + GIC_DIST_CONFIG + confoff);
>> + val = oldval = readl_relaxed(base + confoff);
>> if (type & IRQ_TYPE_LEVEL_MASK)
>> val &= ~confmask;
>> else if (type & IRQ_TYPE_EDGE_BOTH)
>> @@ -83,14 +83,10 @@ int gic_configure_irq(unsigned int irq, unsigned int type,
>> * does not allow us to set the configuration or we are in a
>> * non-secure mode, and hence it may not be catastrophic.
>> */
>> - writel_relaxed(val, base + GIC_DIST_CONFIG + confoff);
>> - if (readl_relaxed(base + GIC_DIST_CONFIG + confoff) != val) {
>> - if (WARN_ON(irq >= 32))
>> - ret = -EINVAL;
>
> Since this WARN_ON is dropped, the comment above should also be updated.
> But what is the reason for deleting it? (It may give us some points
> when we fail to set type for SPIs.)

The core code already warns in the case where irq_set_type() fails, and
the duplication of warnings is pretty superfluous.

Thanks,

M.
--
Jazz is not dead, it just smells funny...