Re: [v8,5/7] PCI: mediatek-gen3: Add MSI support

[Jianjun Wang <jianjun.wang@mediatek.com>]

On Thu, 2021-03-11 at 08:19 +0000, Marc Zyngier wrote:
> On 2021-03-11 00:05, Pali Rohár wrote:
> > On Wednesday 24 February 2021 14:11:30 Jianjun Wang wrote:
> >> +static int mtk_msi_bottom_domain_alloc(struct irq_domain *domain,
> >> +				       unsigned int virq, unsigned int nr_irqs,
> >> +				       void *arg)
> >> +{
> >> +	struct mtk_pcie_port *port = domain->host_data;
> >> +	struct mtk_msi_set *msi_set;
> >> +	int i, hwirq, set_idx;
> >> +
> >> +	mutex_lock(&port->lock);
> >> +
> >> +	hwirq = bitmap_find_free_region(port->msi_irq_in_use, 
> >> PCIE_MSI_IRQS_NUM,
> >> +					order_base_2(nr_irqs));
> >> +
> >> +	mutex_unlock(&port->lock);
> >> +
> >> +	if (hwirq < 0)
> >> +		return -ENOSPC;
> >> +
> >> +	set_idx = hwirq / PCIE_MSI_IRQS_PER_SET;
> >> +	msi_set = &port->msi_sets[set_idx];
> >> +
> >> +	for (i = 0; i < nr_irqs; i++)
> >> +		irq_domain_set_info(domain, virq + i, hwirq + i,
> >> +				    &mtk_msi_bottom_irq_chip, msi_set,
> >> +				    handle_edge_irq, NULL, NULL);
> >> +
> >> +	return 0;
> >> +}
> >> +
> >> +static void mtk_msi_bottom_domain_free(struct irq_domain *domain,
> >> +				       unsigned int virq, unsigned int nr_irqs)
> >> +{
> >> +	struct mtk_pcie_port *port = domain->host_data;
> >> +	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
> >> +
> >> +	mutex_lock(&port->lock);
> >> +
> >> +	bitmap_clear(port->msi_irq_in_use, data->hwirq, nr_irqs);
> > 
> > Marc, should not be there bitmap_release_region() with order_base_2()?
> > 
> > bitmap_release_region(port->msi_irq_in_use, data->hwirq, 
> > order_base_2(nr_irqs));
> > 
> > Because mtk_msi_bottom_domain_alloc() is allocating
> > order_base_2(nr_irqs) interrupts, not only nr_irqs.
> 
> Indeed, good catch.

I will fix it in the next version, thanks for your review.

> 
> Thanks,
> 
>          M.