Hi Marc, On Thu, May 12, 2022 at 2:24 PM Marc Zyngier <maz@xxxxxxxxxx> wrote: > > On Thu, 12 May 2022 13:48:53 +0100, > "Lad, Prabhakar" <prabhakar.csengg@xxxxxxxxx> wrote: > > > > Hi Marc, > > > > Thank you for the review. > > > > On Thu, May 12, 2022 at 12:19 PM Marc Zyngier <maz@xxxxxxxxxx> wrote: > > > > > > On Wed, 11 May 2022 19:32:08 +0100, > > > Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> wrote: > > > > > > > > Allow free() callback to be overridden from irq_domain_ops for > > > > hierarchical chips. > > > > > > > > This allows drivers to free any resources which are allocated during > > > > populate_parent_alloc_arg(). > > > > > > Do you mean more than the fwspec? I don't see this being used. > > > > > The free callback is used in patch 5/5 where free is overridden by > > rzg2l_gpio_irq_domain_free. I just gave an example there as an > > populate_parent_alloc_arg() In actual in the child_to_parent_hwirq > > callback I am using a bitmap [0] to get a free tint slot, this bitmap > > needs freeing up when the GPIO interrupt is released from the driver > > that as when overridden free callback frees the allocated tint slot so > > that its available for re-use. > > Right, so that's actually a different life-cycle, and the whole > populate_parent_alloc_arg() is a red herring. What you want is to free > resources that have been allocated via some other paths. It'd be good Is there any other path which I have missed where I can free up resources? > if your commit message actually reflected this instead of using an > example that doesn't actually exist. > My bad, I will update the commit message. > > > > > There is also the question of why we need to have dynamic allocation > > > for the fwspec itself. Why isn't that a simple stack allocation in the > > > context of gpiochip_hierarchy_irq_domain_alloc()? > > > > > you mean gpio core itself should handle the fwspec > > allocation/freeing? > > Yes. The only reason we resort to dynamic allocation is because > ThunderX is using MSI-based GPIOs, and thus doesn't use a fwspec (no > firmware is involved here). > I see.. > If we had a union of the two types, we could just have a stack > variable, and pass that along, completely sidestepping the whole > dynamic allocation/freeing business. > Right agreed. Cheers, Prabhakar
