Re: [PATCH v2 3/4] irqchip: sifive-plic: Differentiate between PLIC handler and context

Anup Patel
2018-11-30T03:55:26Z

On Fri, Nov 30, 2018 at 7:27 AM Atish Patra <atish.patra@wdc.com> wrote:
>
> On 11/27/18 2:04 AM, Anup Patel wrote:
> > We explicitly differentiate between PLIC handler and context because
> > PLIC context is for given mode of HART whereas PLIC handler is per-CPU
> > software construct meant for handling interrupts from a particular
> > PLIC context.
> >
> > Signed-off-by: Anup Patel <anup@brainfault.org>
> > ---
> > drivers/irqchip/irq-sifive-plic.c | 21 +++++++++++++--------
> > 1 file changed, 13 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
> > index 95b4b92ca9b8..ffd4deaca057 100644
> > --- a/drivers/irqchip/irq-sifive-plic.c
> > +++ b/drivers/irqchip/irq-sifive-plic.c
> > @@ -66,8 +66,8 @@ static DEFINE_PER_CPU(struct plic_handler, plic_handlers);
> >
> > struct plic_hw {
> > u32 nr_irqs;
> > + u32 nr_contexts;
> > u32 nr_handlers;
> > - u32 nr_mapped;
> > void __iomem *regs;
> > struct irq_domain *irqdomain;
> > };
> > @@ -191,10 +191,10 @@ static int __init plic_init(struct device_node *node,
> > if (WARN_ON(!plic.nr_irqs))
> > goto out_iounmap;
> >
> > - plic.nr_handlers = of_irq_count(node);
> > - if (WARN_ON(!plic.nr_handlers))
> > + plic.nr_contexts = of_irq_count(node);
> > + if (WARN_ON(!plic.nr_contexts))
> > goto out_iounmap;
> > - if (WARN_ON(plic.nr_handlers < num_possible_cpus()))
> > + if (WARN_ON(plic.nr_contexts < num_possible_cpus()))
> > goto out_iounmap;
> >
> > plic.irqdomain = irq_domain_add_linear(node, plic.nr_irqs + 1,
> > @@ -202,7 +202,7 @@ static int __init plic_init(struct device_node *node,
> > if (WARN_ON(!plic.irqdomain))
> > goto out_iounmap;
> >
> > - for (i = 0; i < plic.nr_handlers; i++) {
> > + for (i = 0; i < plic.nr_contexts; i++) {
> > struct of_phandle_args parent;
> > struct plic_handler *handler;
> > irq_hw_number_t hwirq;
> > @@ -225,6 +225,11 @@ static int __init plic_init(struct device_node *node,
> >
> > cpu = riscv_hartid_to_cpuid(hartid);
> > handler = per_cpu_ptr(&plic_handlers, cpu);
> > + if (handler->present) {
> > + pr_warn("handler not available for context %d.\n", i);
> > + continue;
> > + }
> > +
>
> Ahh you have the handler->present check here in this patch. This should
> be in the 2nd patch. This change doesn't match the commit text anyways.

Sure, will do.

>
> Everything else just variable renaming which can be separated.
> nr_handlers->nr_contexts
> nr_mapped->nr_handlers
>

Sure, will update commit text.

Thanks,
Anup