[tip:irq/core] irqchip/bcm2835: Add support for being used as a second level controller
From: tip-bot for Eric Anholt
Date: Thu Aug 20 2015 - 16:43:13 EST
Commit-ID: a493f339a88ddd20693460c1dcf8230aa3732b8b
Gitweb: http://git.kernel.org/tip/a493f339a88ddd20693460c1dcf8230aa3732b8b
Author: Eric Anholt <eric@xxxxxxxxxx>
AuthorDate: Thu, 6 Aug 2015 16:00:31 -0700
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 20 Aug 2015 22:38:41 +0200
irqchip/bcm2835: Add support for being used as a second level controller
The BCM2836 (Raspberry Pi 2) uses two levels of interrupt handling
with the CPU-local interrupts being the root, so we need to register
ours as chained off of the CPU's local interrupt.
Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>
Acked-by: Stephen Warren <swarren@xxxxxxxxxxxxx>
Cc: linux-rpi-kernel@xxxxxxxxxxxxxxxxxxx
Cc: Lee Jones <lee@xxxxxxxxxx>
Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1438902033-31477-3-git-send-email-eric@xxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
.../brcm,bcm2835-armctrl-ic.txt | 25 ++++++++++++-
drivers/irqchip/irq-bcm2835.c | 43 ++++++++++++++++++++--
2 files changed, 64 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt b/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
index 7da578d..2d6c8bb 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
+++ b/Documentation/devicetree/bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
@@ -5,9 +5,14 @@ The BCM2835 contains a custom top-level interrupt controller, which supports
controller, or the HW block containing it, is referred to occasionally
as "armctrl" in the SoC documentation, hence naming of this binding.
+The BCM2836 contains the same interrupt controller with the same
+interrupts, but the per-CPU interrupt controller is the root, and an
+interrupt there indicates that the ARMCTRL has an interrupt to handle.
+
Required properties:
-- compatible : should be "brcm,bcm2835-armctrl-ic"
+- compatible : should be "brcm,bcm2835-armctrl-ic" or
+ "brcm,bcm2836-armctrl-ic"
- reg : Specifies base physical address and size of the registers.
- interrupt-controller : Identifies the node as an interrupt controller
- #interrupt-cells : Specifies the number of cells needed to encode an
@@ -20,6 +25,12 @@ Required properties:
The 2nd cell contains the interrupt number within the bank. Valid values
are 0..7 for bank 0, and 0..31 for bank 1.
+Additional required properties for brcm,bcm2836-armctrl-ic:
+- interrupt-parent : Specifies the parent interrupt controller when this
+ controller is the second level.
+- interrupts : Specifies the interrupt on the parent for this interrupt
+ controller to handle.
+
The interrupt sources are as follows:
Bank 0:
@@ -102,9 +113,21 @@ Bank 2:
Example:
+/* BCM2835, first level */
intc: interrupt-controller {
compatible = "brcm,bcm2835-armctrl-ic";
reg = <0x7e00b200 0x200>;
interrupt-controller;
#interrupt-cells = <2>;
};
+
+/* BCM2836, second level */
+intc: interrupt-controller {
+ compatible = "brcm,bcm2836-armctrl-ic";
+ reg = <0x7e00b200 0x200>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+
+ interrupt-parent = <&local_intc>;
+ interrupts = <8>;
+};
diff --git a/drivers/irqchip/irq-bcm2835.c b/drivers/irqchip/irq-bcm2835.c
index a40d972..ed4ca9d 100644
--- a/drivers/irqchip/irq-bcm2835.c
+++ b/drivers/irqchip/irq-bcm2835.c
@@ -96,6 +96,7 @@ struct armctrl_ic {
static struct armctrl_ic intc __read_mostly;
static void __exception_irq_entry bcm2835_handle_irq(
struct pt_regs *regs);
+static void bcm2836_chained_handle_irq(unsigned int irq, struct irq_desc *desc);
static void armctrl_mask_irq(struct irq_data *d)
{
@@ -139,7 +140,8 @@ static const struct irq_domain_ops armctrl_ops = {
};
static int __init armctrl_of_init(struct device_node *node,
- struct device_node *parent)
+ struct device_node *parent,
+ bool is_2836)
{
void __iomem *base;
int irq, b, i;
@@ -168,10 +170,34 @@ static int __init armctrl_of_init(struct device_node *node,
}
}
- set_handle_irq(bcm2835_handle_irq);
+ if (is_2836) {
+ int parent_irq = irq_of_parse_and_map(node, 0);
+
+ if (!parent_irq) {
+ panic("%s: unable to get parent interrupt.\n",
+ node->full_name);
+ }
+ irq_set_chained_handler(parent_irq, bcm2836_chained_handle_irq);
+ } else {
+ set_handle_irq(bcm2835_handle_irq);
+ }
+
return 0;
}
+static int __init bcm2835_armctrl_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ return armctrl_of_init(node, parent, false);
+}
+
+static int __init bcm2836_armctrl_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ return armctrl_of_init(node, parent, true);
+}
+
+
/*
* Handle each interrupt across the entire interrupt controller. This reads the
* status register before handling each interrupt, which is necessary given that
@@ -219,4 +245,15 @@ static void __exception_irq_entry bcm2835_handle_irq(
handle_IRQ(irq_linear_revmap(intc.domain, hwirq), regs);
}
-IRQCHIP_DECLARE(bcm2835_armctrl_ic, "brcm,bcm2835-armctrl-ic", armctrl_of_init);
+static void bcm2836_chained_handle_irq(unsigned int irq, struct irq_desc *desc)
+{
+ u32 hwirq;
+
+ while ((hwirq = get_next_armctrl_hwirq()) != ~0)
+ generic_handle_irq(irq_linear_revmap(intc.domain, hwirq));
+}
+
+IRQCHIP_DECLARE(bcm2835_armctrl_ic, "brcm,bcm2835-armctrl-ic",
+ bcm2835_armctrl_of_init);
+IRQCHIP_DECLARE(bcm2836_armctrl_ic, "brcm,bcm2836-armctrl-ic",
+ bcm2836_armctrl_of_init);
--
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