Linux-ARM-Kernel Archive on lore.kernel.org
 help / color / Atom feed
From: Florian Fainelli <f.fainelli@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Mark Rutland <mark.rutland@arm.com>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
	<devicetree@vger.kernel.org>,
	Thanu Rangarajan <Thanu.Rangarajan@arm.com>,
	Florian Fainelli <f.fainelli@gmail.com>,
	Souvik Chakravarty <Souvik.Chakravarty@arm.com>,
	Jason Cooper <jason@lakedaemon.net>,
	Marc Zyngier <maz@kernel.org>, Rob Herring <robh+dt@kernel.org>,
	"maintainer:BROADCOM BCM281XX/BCM11XXX/BCM216XX ARM ARCHITE..."
	<bcm-kernel-feedback-list@broadcom.com>,
	Jim Quinlan <james.quinlan@broadcom.com>,
	Sudeep Holla <Sudeep.Holla@arm.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"moderated list:BROADCOM BCM2835 ARM ARCHITECTURE"
	<linux-arm-kernel@lists.infradead.org>
Subject: [PATCH RFC 2/2] irqchip/gic: Allow the use of SGI interrupts
Date: Tue, 22 Oct 2019 17:05:47 -0700
Message-ID: <20191023000547.7831-3-f.fainelli@gmail.com> (raw)
In-Reply-To: <20191023000547.7831-1-f.fainelli@gmail.com>

SGI interrupts are a convenient way for trusted firmware to target a
specific set of CPUs. Update the ARM GIC code to allow the translation
and mapping of SGI interrupts.

Since the kernel already uses SGIs for various inter-processor interrupt
activities, we specifically make sure that we do not let users of the
IRQ API to even try to map those.

Internal IPIs remain dispatched through handle_IPI() while public SGIs
get promoted to a normal interrupt flow management.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/irqchip/irq-gic.c | 41 +++++++++++++++++++++++++++------------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 30ab623343d3..dcfdbaacdd64 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -385,7 +385,10 @@ static void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
 			 * Pairs with the write barrier in gic_raise_softirq
 			 */
 			smp_rmb();
-			handle_IPI(irqnr, regs);
+			if (irqnr < NR_IPI)
+				handle_IPI(irqnr, regs);
+			else
+				handle_domain_irq(gic->domain, irqnr, regs);
 #endif
 			continue;
 		}
@@ -1005,20 +1008,34 @@ static int gic_irq_domain_translate(struct irq_domain *d,
 		if (fwspec->param_count < 3)
 			return -EINVAL;
 
-		/* Get the interrupt number and add 16 to skip over SGIs */
-		*hwirq = fwspec->param[1] + 16;
-
-		/*
-		 * For SPIs, we need to add 16 more to get the GIC irq
-		 * ID number
-		 */
-		if (!fwspec->param[0])
+		*hwirq = fwspec->param[1];
+		switch (fwspec->param[0]) {
+		case 0:
+			/*
+			 * For SPIs, we need to add 16 more to get the GIC irq
+			 * ID number
+			 */
+			*hwirq += 16;
+			/* fall through */
+		case 1:
+			/* Add 16 to skip over SGIs */
 			*hwirq += 16;
+			*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
 
-		*type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK;
+			/* Make it clear that broken DTs are... broken */
+			WARN_ON(*type == IRQ_TYPE_NONE);
+			break;
+		case 2:
+			/* Refuse to map internal IPIs */
+			if (*hwirq < NR_IPI)
+				return -EPERM;
+
+			*type = IRQ_TYPE_NONE;
+			break;
+		default:
+			break;
+		}
 
-		/* Make it clear that broken DTs are... broken */
-		WARN_ON(*type == IRQ_TYPE_NONE);
 		return 0;
 	}
 
-- 
2.17.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply index

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-23  0:05 [PATCH RFC 0/2] " Florian Fainelli
2019-10-23  0:05 ` [PATCH RFC 1/2] dt-bindings: Define interrupt type for " Florian Fainelli
2019-10-23  0:05 ` Florian Fainelli [this message]
2019-10-23 13:22   ` [PATCH RFC 2/2] irqchip/gic: Allow the use of " Marc Zyngier
2019-10-23 17:02     ` Florian Fainelli
2019-10-24  8:27       ` Marc Zyngier

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=20191023000547.7831-3-f.fainelli@gmail.com \
    --to=f.fainelli@gmail.com \
    --cc=Souvik.Chakravarty@arm.com \
    --cc=Sudeep.Holla@arm.com \
    --cc=Thanu.Rangarajan@arm.com \
    --cc=bcm-kernel-feedback-list@broadcom.com \
    --cc=devicetree@vger.kernel.org \
    --cc=james.quinlan@broadcom.com \
    --cc=jason@lakedaemon.net \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=maz@kernel.org \
    --cc=robh+dt@kernel.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

Linux-ARM-Kernel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-arm-kernel/0 linux-arm-kernel/git/0.git
	git clone --mirror https://lore.kernel.org/linux-arm-kernel/1 linux-arm-kernel/git/1.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-arm-kernel linux-arm-kernel/ https://lore.kernel.org/linux-arm-kernel \
		linux-arm-kernel@lists.infradead.org
	public-inbox-index linux-arm-kernel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.infradead.lists.linux-arm-kernel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git