From: Atish Patra <atish.patra@wdc.com>
To: Anup Patel <anup@brainfault.org>,
Palmer Dabbelt <palmer@sifive.com>,
Albert Ou <aou@eecs.berkeley.edu>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Thomas Gleixner <tglx@linutronix.de>,
Jason Cooper <jason@lakedaemon.net>,
Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@infradead.org>,
"linux-riscv@lists.infradead.org"
<linux-riscv@lists.infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 2/4] irqchip: sifive-plic: More flexible plic_irq_toggle()
Date: Thu, 29 Nov 2018 17:39:45 -0800 [thread overview]
Message-ID: <25c2fafc-a479-911f-a7df-704108da5dc7@wdc.com> (raw)
In-Reply-To: <20181127100317.12809-3-anup@brainfault.org>
On 11/27/18 2:03 AM, Anup Patel wrote:
> We make plic_irq_toggle() more generic so that we can enable/disable
> hwirq for given cpumask. This generic plic_irq_toggle() will be
> eventually used to implement set_affinity for PLIC driver.
>
> Signed-off-by: Anup Patel <anup@brainfault.org>
> ---
> drivers/irqchip/irq-sifive-plic.c | 79 +++++++++++++++----------------
> 1 file changed, 39 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
> index 56fce648a901..95b4b92ca9b8 100644
> --- a/drivers/irqchip/irq-sifive-plic.c
> +++ b/drivers/irqchip/irq-sifive-plic.c
> @@ -55,19 +55,26 @@
> #define CONTEXT_THRESHOLD 0x00
> #define CONTEXT_CLAIM 0x04
>
> -static void __iomem *plic_regs;
> -
> struct plic_handler {
> bool present;
> - int ctxid;
> void __iomem *hart_base;
> raw_spinlock_t enable_lock;
> void __iomem *enable_base;
> };
> +
> static DEFINE_PER_CPU(struct plic_handler, plic_handlers);
>
> -static inline void plic_toggle(struct plic_handler *handler,
> - int hwirq, int enable)
> +struct plic_hw {
> + u32 nr_irqs;
> + u32 nr_handlers;
> + u32 nr_mapped;
Why these three are moved inside a structure? I don't see them being
used outside plic_init. Am I missing something ?
> + void __iomem *regs;
> + struct irq_domain *irqdomain;
> +};
> +
> +static struct plic_hw plic;
> +
> +static void plic_toggle(struct plic_handler *handler, int hwirq, int enable)
> {
> u32 __iomem *reg = handler->enable_base + (hwirq / 32);
> u32 hwirq_mask = 1 << (hwirq % 32);
> @@ -80,27 +87,23 @@ static inline void plic_toggle(struct plic_handler *handler,
> raw_spin_unlock(&handler->enable_lock);
> }
>
> -static inline void plic_irq_toggle(struct irq_data *d, int enable)
> +static void plic_irq_toggle(const struct cpumask *mask, int hwirq, int enable)
> {
> int cpu;
>
> - writel(enable, plic_regs + PRIORITY_BASE + d->hwirq * PRIORITY_PER_ID);
> - for_each_cpu(cpu, irq_data_get_affinity_mask(d)) {
> - struct plic_handler *handler = per_cpu_ptr(&plic_handlers, cpu);
> -
> - if (handler->present)
> - plic_toggle(handler, d->hwirq, enable);
> - }
> + writel(enable, plic.regs + PRIORITY_BASE + hwirq * PRIORITY_PER_ID);
> + for_each_cpu(cpu, mask)
> + plic_toggle(per_cpu_ptr(&plic_handlers, cpu), hwirq, enable);
Any specific reason to remove the handler->present check.
Moreover, only this part matches commit text. Most of the other changes
looks like cosmetic cleanup because of variable is moved to a structure.
May be separate patch for those changes if they are are required at all.
> }
>
> static void plic_irq_enable(struct irq_data *d)
> {
> - plic_irq_toggle(d, 1);
> + plic_irq_toggle(irq_data_get_affinity_mask(d), d->hwirq, 1);
> }
>
> static void plic_irq_disable(struct irq_data *d)
> {
> - plic_irq_toggle(d, 0);
> + plic_irq_toggle(irq_data_get_affinity_mask(d), d->hwirq, 0);
> }
>
> static struct irq_chip plic_chip = {
> @@ -127,8 +130,6 @@ static const struct irq_domain_ops plic_irqdomain_ops = {
> .xlate = irq_domain_xlate_onecell,
> };
>
> -static struct irq_domain *plic_irqdomain;
> -
> /*
> * Handling an interrupt is a two-step process: first you claim the interrupt
> * by reading the claim register, then you complete the interrupt by writing
> @@ -145,7 +146,7 @@ static void plic_handle_irq(struct pt_regs *regs)
>
> csr_clear(sie, SIE_SEIE);
> while ((hwirq = readl(claim))) {
> - int irq = irq_find_mapping(plic_irqdomain, hwirq);
> + int irq = irq_find_mapping(plic.irqdomain, hwirq);
>
> if (unlikely(irq <= 0))
> pr_warn_ratelimited("can't find mapping for hwirq %lu\n",
> @@ -174,36 +175,34 @@ static int plic_find_hart_id(struct device_node *node)
> static int __init plic_init(struct device_node *node,
> struct device_node *parent)
> {
> - int error = 0, nr_handlers, nr_mapped = 0, i;
> - u32 nr_irqs;
> + int error = 0, i;
>
> - if (plic_regs) {
> + if (plic.regs) {
> pr_warn("PLIC already present.\n");
> return -ENXIO;
> }
>
> - plic_regs = of_iomap(node, 0);
> - if (WARN_ON(!plic_regs))
> + plic.regs = of_iomap(node, 0);
> + if (WARN_ON(!plic.regs))
> return -EIO;
>
> error = -EINVAL;
> - of_property_read_u32(node, "riscv,ndev", &nr_irqs);
> - if (WARN_ON(!nr_irqs))
> + of_property_read_u32(node, "riscv,ndev", &plic.nr_irqs);
> + if (WARN_ON(!plic.nr_irqs))
> goto out_iounmap;
>
> - nr_handlers = of_irq_count(node);
> - if (WARN_ON(!nr_handlers))
> + plic.nr_handlers = of_irq_count(node);
> + if (WARN_ON(!plic.nr_handlers))
> goto out_iounmap;
> - if (WARN_ON(nr_handlers < num_possible_cpus()))
> + if (WARN_ON(plic.nr_handlers < num_possible_cpus()))
> goto out_iounmap;
>
> - error = -ENOMEM;
> - plic_irqdomain = irq_domain_add_linear(node, nr_irqs + 1,
> - &plic_irqdomain_ops, NULL);
> - if (WARN_ON(!plic_irqdomain))
> + plic.irqdomain = irq_domain_add_linear(node, plic.nr_irqs + 1,
> + &plic_irqdomain_ops, NULL);
> + if (WARN_ON(!plic.irqdomain))
> goto out_iounmap;
>
Should we return EINVAL if irq_domain_add_linear fails ? Earlier, it was
returning ENOMEM.
> - for (i = 0; i < nr_handlers; i++) {
> + for (i = 0; i < plic.nr_handlers; i++) {
> struct of_phandle_args parent;
> struct plic_handler *handler;
> irq_hw_number_t hwirq;
> @@ -227,27 +226,27 @@ static int __init plic_init(struct device_node *node,
> cpu = riscv_hartid_to_cpuid(hartid);
> handler = per_cpu_ptr(&plic_handlers, cpu);
> handler->present = true;
> - handler->ctxid = i;
The previous patch removed all the usage of ctxid. So this line also can
be included in that patch as well to make it more coherent.
Regards,
Atish
> handler->hart_base =
> - plic_regs + CONTEXT_BASE + i * CONTEXT_PER_HART;
> + plic.regs + CONTEXT_BASE + i * CONTEXT_PER_HART;
> raw_spin_lock_init(&handler->enable_lock);
> handler->enable_base =
> - plic_regs + ENABLE_BASE + i * ENABLE_PER_HART;
> + plic.regs + ENABLE_BASE + i * ENABLE_PER_HART;
>
> /* priority must be > threshold to trigger an interrupt */
> writel(0, handler->hart_base + CONTEXT_THRESHOLD);
> - for (hwirq = 1; hwirq <= nr_irqs; hwirq++)
> + for (hwirq = 1; hwirq <= plic.nr_irqs; hwirq++)
> plic_toggle(handler, hwirq, 0);
> - nr_mapped++;
> +
> + plic.nr_mapped++;
> }
>
> pr_info("mapped %d interrupts to %d (out of %d) handlers.\n",
> - nr_irqs, nr_mapped, nr_handlers);
> + plic.nr_irqs, plic.nr_mapped, plic.nr_handlers);
> set_handle_irq(plic_handle_irq);
> return 0;
>
> out_iounmap:
> - iounmap(plic_regs);
> + iounmap(plic.regs);
> return error;
> }
>
>
next prev parent reply other threads:[~2018-11-30 1:39 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-27 10:03 [PATCH v2 0/4] IRQ affinity support in PLIC driver Anup Patel
2018-11-27 10:03 ` [PATCH v2 1/4] irqchip: sifive-plic: Pre-compute context hart base and enable base Anup Patel
2018-11-30 0:35 ` Atish Patra
2018-11-30 3:34 ` Anup Patel
2018-11-27 10:03 ` [PATCH v2 2/4] irqchip: sifive-plic: More flexible plic_irq_toggle() Anup Patel
2018-11-30 1:39 ` Atish Patra [this message]
2018-11-30 3:51 ` Anup Patel
2018-11-27 10:03 ` [PATCH v2 3/4] irqchip: sifive-plic: Differentiate between PLIC handler and context Anup Patel
2018-11-30 1:57 ` Atish Patra
2018-11-30 3:55 ` Anup Patel
2018-11-27 10:03 ` [PATCH v2 4/4] irqchip: sifive-plic: Implement irq_set_affinity() for SMP host Anup Patel
2018-11-30 5:59 ` Atish Patra
2018-11-30 7:51 ` Anup Patel
2018-11-30 7:54 ` Atish Patra
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=25c2fafc-a479-911f-a7df-704108da5dc7@wdc.com \
--to=atish.patra@wdc.com \
--cc=anup@brainfault.org \
--cc=aou@eecs.berkeley.edu \
--cc=daniel.lezcano@linaro.org \
--cc=hch@infradead.org \
--cc=jason@lakedaemon.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=marc.zyngier@arm.com \
--cc=palmer@sifive.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).