All the mail mirrored from lore.kernel.org
 help / color / mirror / Atom feed
From: Stephen Warren <swarren@wwwdotorg.org>
To: Eric Anholt <eric@anholt.net>, linux-arm-kernel@lists.infradead.org
Cc: linux-rpi-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Lee Jones <lee@kernel.org>,
	devicetree@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
	Jason Cooper <jason@lakedaemon.net>,
	Andrea Merello <andrea.merello@gmail.com>
Subject: Re: [PATCH 4/4] irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2.
Date: Fri, 10 Jul 2015 23:13:15 -0600	[thread overview]
Message-ID: <55A0A5EB.4090007@wwwdotorg.org> (raw)
In-Reply-To: <1436303617-17185-5-git-send-email-eric@anholt.net>

On 07/07/2015 03:13 PM, Eric Anholt wrote:
> This interrupt controller is the new root interrupt controller with
> the timer, PMU events, and IPIs, and the bcm2835's interrupt
> controller is chained off of it to handle the peripherals.
> 
> SMP IPI support was mostly written by Andrea Merello, while I wrote
> most of the rest of the IRQ handling.
> 
> Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
> Signed-off-by: Eric Anholt <eric@anholt.net>

I'd expect the git patch author to be Andrea if he wrote the original
patch and you enhanced it.

> diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c

> +struct arm_local_intc {
> +	struct irq_domain *domain;
> +	void __iomem *base;
> +};
> +
> +static struct arm_local_intc intc  __read_mostly;

It'd be nice to give everything (types, functions, variables) a
consistent symbol prefix; bcm2836_arm_irqchip_ sounds like a good
bikeshed to me, but perhaps just propagating the above arm_local_ to the
functions too would be good, although that seems to risk symbol name
collisions with other ARM SoCs.

> +static void bcm2836_mask_per_cpu_irq(unsigned int reg, unsigned int bit)
> +{
> +	void __iomem *reg_base = intc.base + reg;
> +	unsigned int i;
> +
> +	for (i = 0; i < 4; i++)

Is "4" there the CPU count? Perhaps this should use one of the Linux
APIs to query the CPU count rather than hard-coding it?

Should per-CPU IRQs automatically be masked on all CPUs at once, or only
on the current CPU? A very quick look at the ARM GIC driver implies it
doesn't iterate over all CPUs when masking per-CPU IRQs.

> +static void bcm2836_mask_gpu_irq(struct irq_data *d)
> +{
> +}
> +
> +static void bcm2836_unmask_gpu_irq(struct irq_data *d)
> +{
> +}

If the IRQs can't be masked, should these functions actually be implemented?

> +static void __exception_irq_entry bcm2836_handle_irq(struct pt_regs *regs)
> +{
> +	int cpu = smp_processor_id();
> +	u32 stat;
> +
> +	stat = readl_relaxed(intc.base + LOCAL_IRQ_PENDING0 + 4 * cpu);
> +	if (stat & 0x10) {
> +		void __iomem *mailbox0 = (intc.base +
> +					  LOCAL_MAILBOX0_CLR0 + 16 * cpu);
> +		u32 mbox_val = readl(mailbox0);
> +		u32 ipi = ffs(mbox_val) - 1;
> +
> +		writel(1 << ipi, mailbox0);
> +		handle_IPI(ipi, regs);

Given that bcm2836_send_ipi() is #ifdef CONFIG_SMP, should this code be too?

WARNING: multiple messages have this Message-ID (diff)
From: Stephen Warren <swarren@wwwdotorg.org>
To: Eric Anholt <eric@anholt.net>, linux-arm-kernel@lists.infradead.org
Cc: devicetree@vger.kernel.org, Jason Cooper <jason@lakedaemon.net>,
	Andrea Merello <andrea.merello@gmail.com>,
	Lee Jones <lee@kernel.org>,
	linux-kernel@vger.kernel.org,
	linux-rpi-kernel@lists.infradead.org,
	Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 4/4] irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2.
Date: Fri, 10 Jul 2015 23:13:15 -0600	[thread overview]
Message-ID: <55A0A5EB.4090007@wwwdotorg.org> (raw)
In-Reply-To: <1436303617-17185-5-git-send-email-eric@anholt.net>

On 07/07/2015 03:13 PM, Eric Anholt wrote:
> This interrupt controller is the new root interrupt controller with
> the timer, PMU events, and IPIs, and the bcm2835's interrupt
> controller is chained off of it to handle the peripherals.
> 
> SMP IPI support was mostly written by Andrea Merello, while I wrote
> most of the rest of the IRQ handling.
> 
> Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
> Signed-off-by: Eric Anholt <eric@anholt.net>

I'd expect the git patch author to be Andrea if he wrote the original
patch and you enhanced it.

> diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c

> +struct arm_local_intc {
> +	struct irq_domain *domain;
> +	void __iomem *base;
> +};
> +
> +static struct arm_local_intc intc  __read_mostly;

It'd be nice to give everything (types, functions, variables) a
consistent symbol prefix; bcm2836_arm_irqchip_ sounds like a good
bikeshed to me, but perhaps just propagating the above arm_local_ to the
functions too would be good, although that seems to risk symbol name
collisions with other ARM SoCs.

> +static void bcm2836_mask_per_cpu_irq(unsigned int reg, unsigned int bit)
> +{
> +	void __iomem *reg_base = intc.base + reg;
> +	unsigned int i;
> +
> +	for (i = 0; i < 4; i++)

Is "4" there the CPU count? Perhaps this should use one of the Linux
APIs to query the CPU count rather than hard-coding it?

Should per-CPU IRQs automatically be masked on all CPUs at once, or only
on the current CPU? A very quick look at the ARM GIC driver implies it
doesn't iterate over all CPUs when masking per-CPU IRQs.

> +static void bcm2836_mask_gpu_irq(struct irq_data *d)
> +{
> +}
> +
> +static void bcm2836_unmask_gpu_irq(struct irq_data *d)
> +{
> +}

If the IRQs can't be masked, should these functions actually be implemented?

> +static void __exception_irq_entry bcm2836_handle_irq(struct pt_regs *regs)
> +{
> +	int cpu = smp_processor_id();
> +	u32 stat;
> +
> +	stat = readl_relaxed(intc.base + LOCAL_IRQ_PENDING0 + 4 * cpu);
> +	if (stat & 0x10) {
> +		void __iomem *mailbox0 = (intc.base +
> +					  LOCAL_MAILBOX0_CLR0 + 16 * cpu);
> +		u32 mbox_val = readl(mailbox0);
> +		u32 ipi = ffs(mbox_val) - 1;
> +
> +		writel(1 << ipi, mailbox0);
> +		handle_IPI(ipi, regs);

Given that bcm2836_send_ipi() is #ifdef CONFIG_SMP, should this code be too?

WARNING: multiple messages have this Message-ID (diff)
From: swarren@wwwdotorg.org (Stephen Warren)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 4/4] irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2.
Date: Fri, 10 Jul 2015 23:13:15 -0600	[thread overview]
Message-ID: <55A0A5EB.4090007@wwwdotorg.org> (raw)
In-Reply-To: <1436303617-17185-5-git-send-email-eric@anholt.net>

On 07/07/2015 03:13 PM, Eric Anholt wrote:
> This interrupt controller is the new root interrupt controller with
> the timer, PMU events, and IPIs, and the bcm2835's interrupt
> controller is chained off of it to handle the peripherals.
> 
> SMP IPI support was mostly written by Andrea Merello, while I wrote
> most of the rest of the IRQ handling.
> 
> Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
> Signed-off-by: Eric Anholt <eric@anholt.net>

I'd expect the git patch author to be Andrea if he wrote the original
patch and you enhanced it.

> diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c

> +struct arm_local_intc {
> +	struct irq_domain *domain;
> +	void __iomem *base;
> +};
> +
> +static struct arm_local_intc intc  __read_mostly;

It'd be nice to give everything (types, functions, variables) a
consistent symbol prefix; bcm2836_arm_irqchip_ sounds like a good
bikeshed to me, but perhaps just propagating the above arm_local_ to the
functions too would be good, although that seems to risk symbol name
collisions with other ARM SoCs.

> +static void bcm2836_mask_per_cpu_irq(unsigned int reg, unsigned int bit)
> +{
> +	void __iomem *reg_base = intc.base + reg;
> +	unsigned int i;
> +
> +	for (i = 0; i < 4; i++)

Is "4" there the CPU count? Perhaps this should use one of the Linux
APIs to query the CPU count rather than hard-coding it?

Should per-CPU IRQs automatically be masked on all CPUs at once, or only
on the current CPU? A very quick look@the ARM GIC driver implies it
doesn't iterate over all CPUs when masking per-CPU IRQs.

> +static void bcm2836_mask_gpu_irq(struct irq_data *d)
> +{
> +}
> +
> +static void bcm2836_unmask_gpu_irq(struct irq_data *d)
> +{
> +}

If the IRQs can't be masked, should these functions actually be implemented?

> +static void __exception_irq_entry bcm2836_handle_irq(struct pt_regs *regs)
> +{
> +	int cpu = smp_processor_id();
> +	u32 stat;
> +
> +	stat = readl_relaxed(intc.base + LOCAL_IRQ_PENDING0 + 4 * cpu);
> +	if (stat & 0x10) {
> +		void __iomem *mailbox0 = (intc.base +
> +					  LOCAL_MAILBOX0_CLR0 + 16 * cpu);
> +		u32 mbox_val = readl(mailbox0);
> +		u32 ipi = ffs(mbox_val) - 1;
> +
> +		writel(1 << ipi, mailbox0);
> +		handle_IPI(ipi, regs);

Given that bcm2836_send_ipi() is #ifdef CONFIG_SMP, should this code be too?

  reply	other threads:[~2015-07-11  6:29 UTC|newest]

Thread overview: 37+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-07 21:13 Raspberry Pi 2 support, part 1: Interrupt controller Eric Anholt
2015-07-07 21:13 ` Eric Anholt
2015-07-07 21:13 ` Eric Anholt
2015-07-07 21:13 ` [PATCH 1/4] irqchip: bcm2835: Refactor handle_IRQ() calls out of MAKE_HWIRQ Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-07 21:13 ` [PATCH 2/4] irqchip: bcm2835: If a parent interrupt is registered, chain from it Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-07 21:13 ` [PATCH 3/4] irqchip: Add documentation for the bcm2836 interrupt controller Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-11  4:57   ` Stephen Warren
2015-07-11  4:57     ` Stephen Warren
2015-07-11  4:57     ` Stephen Warren
2015-07-11  6:01     ` Eric Anholt
2015-07-11  6:01       ` Eric Anholt
2015-07-11  6:01       ` Eric Anholt
2015-07-14  5:08       ` Stephen Warren
2015-07-14  5:08         ` Stephen Warren
2015-07-14  5:08         ` Stephen Warren
2015-07-07 21:13 ` [PATCH 4/4] irqchip: Add bcm2836 interrupt controller for Raspberry Pi 2 Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-07 21:13   ` Eric Anholt
2015-07-11  5:13   ` Stephen Warren [this message]
2015-07-11  5:13     ` Stephen Warren
2015-07-11  5:13     ` Stephen Warren
2015-07-11  7:51     ` Thomas Gleixner
2015-07-11  7:51       ` Thomas Gleixner
2015-07-11  7:51       ` Thomas Gleixner
2015-07-13 16:06       ` Eric Anholt
2015-07-13 16:06         ` Eric Anholt
2015-07-14  5:09       ` Stephen Warren
2015-07-14  5:09         ` Stephen Warren
2015-07-14  5:09         ` Stephen Warren
2015-07-13 18:48     ` Eric Anholt
2015-07-13 18:48       ` Eric Anholt
2015-07-13 18:48       ` Eric Anholt

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=55A0A5EB.4090007@wwwdotorg.org \
    --to=swarren@wwwdotorg.org \
    --cc=andrea.merello@gmail.com \
    --cc=devicetree@vger.kernel.org \
    --cc=eric@anholt.net \
    --cc=jason@lakedaemon.net \
    --cc=lee@kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rpi-kernel@lists.infradead.org \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.