[PATCH V3] ARM: GIC: Convert GIC library to use the IO relaxed operations
santosh.shilimkar at ti.com
Tue May 3 06:14:53 EDT 2011
On 5/3/2011 3:41 PM, Catalin Marinas wrote:
>> diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
>> index e9c2ff8..80b3d3c 100644
>> --- a/arch/arm/common/gic.c
>> +++ b/arch/arm/common/gic.c
>> @@ -89,7 +89,8 @@ static void gic_mask_irq(struct irq_data *d)
>> u32 mask = 1<< (d->irq % 32);
>> - writel(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
>> + writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
>> + readl_relaxed(gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
> As I commented on the version 2 of this patch, I don't think we should
> even bother with the additional readl_relaxed() here. It's not enough to
> prevent spurious interrupts anyway.
I forgot to drop this one.
>> @@ -392,6 +393,7 @@ void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
>> unsigned long map = *cpus_addr(*mask);
>> /* this always happens on GIC0 */
>> - writel(map<< 16 | irq, gic_data.dist_base + GIC_DIST_SOFTINT);
>> + dsb();
>> + writel_relaxed(map<< 16 | irq, gic_data.dist_base + GIC_DIST_SOFTINT);
> I would add a comment before the dsb() on why it is needed. Maybe something like:
> * Ensure that stores to Normal memory are visible to the other CPUs before
> * issuing the IPI.
> Otherwise the patch looks fine (I'll add my ack after you fix the above).
Thanks. Will add above comment, drop the readl and repost with your ack.
Same will push it the patch system
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