From: Eric Anholt <eric@anholt.net>
To: linux-rpi-kernel@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org,
Stephen Warren <swarren@wwwdotorg.org>,
Lee Jones <lee@kernel.org>,
Florian Fainelli <f.fainelli@gmail.com>,
devicetree@vger.kernel.org, Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Ian Campbell <ijc+devicetree@hellion.org.uk>,
Kumar Gala <galak@codeaurora.org>,
bcm-kernel-feedback-list@broadcom.com,
Ray Jui <rjui@broadcom.com>,
Scott Branden <sbranden@broadcom.com>,
Thomas Gleixner <tglx@linutronix.de>,
Jason Cooper <jason@lakedaemon.net>,
Marc Zyngier <marc.zyngier@arm.com>,
Eric Anholt <eric@anholt.net>
Subject: [PATCH v2 1/8] irq: bcm2836: Fix initialization of the LOCAL_IRQ_CNT*IRQ timers
Date: Wed, 16 Dec 2015 15:55:08 -0800 [thread overview]
Message-ID: <1450310115-22163-2-git-send-email-eric@anholt.net> (raw)
In-Reply-To: <1450310115-22163-1-git-send-email-eric@anholt.net>
The irqchip's register area includes the the setup for the timer's
scaling factors, and for the platform we want a fixed configuration of
these registers.
Signed-off-by: Eric Anholt <eric@anholt.net>
---
drivers/irqchip/irq-bcm2836.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/drivers/irqchip/irq-bcm2836.c b/drivers/irqchip/irq-bcm2836.c
index f687082..6ec125e 100644
--- a/drivers/irqchip/irq-bcm2836.c
+++ b/drivers/irqchip/irq-bcm2836.c
@@ -21,6 +21,9 @@
#include <linux/irqdomain.h>
#include <asm/exception.h>
+#define LOCAL_CONTROL 0x000
+#define LOCAL_PRESCALER 0x008
+
/*
* The low 2 bits identify the CPU that the GPU IRQ goes to, and the
* next 2 bits identify the CPU that the GPU FIQ goes to.
@@ -237,6 +240,27 @@ bcm2836_arm_irqchip_smp_init(void)
#endif
}
+/*
+ * The LOCAL_IRQ_CNT* timer firings are based off of the external
+ * oscillator with some scaling. The firmware sets up CNTFRQ to
+ * report 19.2Mhz, but doesn't set up the scaling registers.
+ */
+static void bcm2835_init_local_timer_frequency(void)
+{
+ /*
+ * Set the timer to source from the 19.2Mhz crystal clock (bit
+ * 8 unset), and only increment by 1 instead of 2 (bit 9
+ * unset).
+ */
+ writel(0, intc.base + LOCAL_CONTROL);
+
+ /*
+ * Set the timer prescaler to 1:1 (timer freq = input freq *
+ * 2**31 / prescaler)
+ */
+ writel(0x80000000, intc.base + LOCAL_PRESCALER);
+}
+
static int __init bcm2836_arm_irqchip_l1_intc_of_init(struct device_node *node,
struct device_node *parent)
{
@@ -246,6 +270,8 @@ static int __init bcm2836_arm_irqchip_l1_intc_of_init(struct device_node *node,
node->full_name);
}
+ bcm2835_init_local_timer_frequency();
+
intc.domain = irq_domain_add_linear(node, LAST_IRQ + 1,
&bcm2836_arm_irqchip_intc_ops,
NULL);
--
2.6.2
next prev parent reply other threads:[~2015-12-16 23:55 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-16 23:55 [PATCH v2 0/8] Raspberry Pi 2 support Eric Anholt
2015-12-16 23:55 ` Eric Anholt [this message]
2015-12-16 23:55 ` [PATCH v2 2/8] irq: bcm2836: Add SMP support for the 2836 Eric Anholt
2015-12-17 5:17 ` Baruch Siach
2015-12-16 23:55 ` [PATCH v2 3/8] dt-bindings: Add root properties for Raspberry Pi 2 Eric Anholt
2015-12-19 4:18 ` Rob Herring
2015-12-16 23:55 ` [PATCH v2 4/8] ARM: bcm2835: Split the DT for peripherals from the DT for the CPU Eric Anholt
2015-12-18 10:00 ` Alexander Aring
2015-12-21 23:09 ` Eric Anholt
2015-12-16 23:55 ` [PATCH v2 5/8] ARM: bcm2835: Move the CPU/peripheral include out of common RPi DT Eric Anholt
2015-12-16 23:55 ` [PATCH v2 6/8] ARM: bcm2835: Add devicetree for bcm2836 and Raspberry Pi 2 B Eric Anholt
2015-12-22 10:11 ` Alexander Aring
2015-12-16 23:55 ` [PATCH v2 7/8] ARM: bcm2835: Add a compat string for bcm2836 machine probe Eric Anholt
2015-12-16 23:55 ` [PATCH v2 8/8] ARM: bcm2835: Add Kconfig support for bcm2836 Eric Anholt
2015-12-26 22:38 ` Eric Anholt
2016-01-03 21:53 ` Noralf Trønnes
2015-12-17 0:03 ` [PATCH v2 0/8] Raspberry Pi 2 support Arnd Bergmann
2015-12-17 0:37 ` Eric Anholt
2015-12-17 8:48 ` Stefan Wahren
2015-12-17 10:26 ` Arnd Bergmann
2015-12-18 10:08 ` Alexander Aring
2015-12-18 10:55 ` Alexander Aring
2015-12-20 22:11 ` Alexander Aring
2015-12-21 23:07 ` Eric Anholt
2015-12-22 14:26 ` Alexander Aring
2015-12-22 19:01 ` Eric Anholt
2015-12-26 21:38 ` Noralf Trønnes
2015-12-21 23:11 ` Arnd Bergmann
2015-12-22 14:20 ` Alexander Aring
2015-12-22 21:23 ` Arnd Bergmann
2015-12-25 0:01 ` Eric Anholt
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