Re: [PATCH v4 2/2] PCI: Rockchip: Add Rockchip PCIe controller support

[Shawn Lin]

å 2016/7/1 18:32, Marc Zyngier åé:
> On 01/07/16 02:24, Shawn Lin wrote:
> > This patch adds Rockchip PCIe controller support found
> > on RK3399 Soc platform.
> >
> > Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> >
> > ---
>
> [...]
>
> > +static void rockchip_pcie_legacy_int_handler(struct irq_desc *desc)
> > +{
> > +	struct irq_chip *chip = irq_desc_get_chip(desc);
> > +	struct rockchip_pcie_port *port;
> > +	u32 reg;
> > +
> > +	chained_irq_enter(chip, desc);
> > +	port = irq_desc_get_handler_data(desc);
> > +
> > +	reg = pcie_read(port, PCIE_CLIENT_INT_STATUS);
> > +	reg = (reg & ROCKCHIP_PCIE_RPIFR1_INTR_MASK) >>
> > +	       ROCKCHIP_PCIE_RPIFR1_INTR_SHIFT;
> > +	if (reg)
> > +		generic_handle_irq(irq_find_mapping(port->irq_domain,
> > +						    ffs(reg)));
>
> Can't you get multiple pending interrupts at the same time? Here, you
> seem to only process one interrupt at a time, which is going to be
> pretty inefficient.

Yup, will fix it, thanks.

> How about something like:
>
> 	while (reg) {
> 		int hwirq = ffs(reg);
> 		int irq;
> 		
> 		reg &= ~BIT(hwirq);
> 		irq = irq_find_mapping(port->irq_domain, hwirq);
> 		if (irq)
> 			generic_handle_irq(irq);
> 	}
>
> > +	chained_irq_exit(chip, desc);
> > +}
> > +
>
> Thanks,
>
> 	M.


--
Best Regards
Shawn Lin