mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-23 23:42:43 +00:00
8c405cdccc
The patches were generated from the RPi repo with the following command: git format-patch v6.6.34..rpi-6.1.y Some patches needed rebasing and, as usual, the applied and reverted, wireless drivers, Github workflows, READMEs and defconfigs patches were removed. Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
115 lines
3.7 KiB
Diff
115 lines
3.7 KiB
Diff
From 273ee28efedfdfc546906da067581ba9d86edfc9 Mon Sep 17 00:00:00 2001
|
|
From: Michael Zoran <mzoran@crowfest.net>
|
|
Date: Sat, 14 Jan 2017 21:43:57 -0800
|
|
Subject: [PATCH 0112/1085] ARM64: Round-Robin dispatch IRQs between CPUs.
|
|
|
|
IRQ-CPU mapping is round robined on ARM64 to increase
|
|
concurrency and allow multiple interrupts to be serviced
|
|
at a time. This reduces the need for FIQ.
|
|
|
|
Signed-off-by: Michael Zoran <mzoran@crowfest.net>
|
|
|
|
drivers: irqchip: irq-bcm2835: Concurrency fix
|
|
|
|
The commit shown in Fixes: aims to improve interrupt throughput by
|
|
getting the handlers invoked on different CPU cores. It does so (*) by
|
|
using an irq_ack hook to change the interrupt routing.
|
|
|
|
Unfortunately, the IRQ status bits must be cleared at source, which only
|
|
happens once the interrupt handler has run - there is no easy way for
|
|
one core to claim one of the IRQs before sending the remainder to the
|
|
next core on the list, so waking another core immediately results in a
|
|
race with a chance of both cores handling the same IRQ. It is probably
|
|
for this reason that the routing change is deferred to irq_ack, but that
|
|
doesn't guarantee no clashes - after irq_ack is called, control returns
|
|
to bcm2836_chained_handler_irq which proceeds to check for other pending
|
|
IRQs at a time when the next core is probably doing the same thing.
|
|
|
|
Since the whole point of the original commit is to distribute the IRQ
|
|
handling, there is no reason to attempt to handle multiple IRQs in one
|
|
interrupt callback, so the problem can be solved (or at least made much
|
|
harder to reproduce) by changing a "while" into an "if", so that each
|
|
invocation only handles one IRQ.
|
|
|
|
(*) I'm not convinced it's as effective as claimed since irq_ack is
|
|
called _after_ the interrupt handler, but the author thought it made a
|
|
difference.
|
|
|
|
See: https://github.com/raspberrypi/linux/issues/5214
|
|
https://github.com/raspberrypi/linux/pull/1794
|
|
|
|
Fixes: fd4c9785bde8 ("ARM64: Round-Robin dispatch IRQs between CPUs.")
|
|
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
|
|
---
|
|
drivers/irqchip/irq-bcm2835.c | 18 ++++++++++++++++--
|
|
drivers/irqchip/irq-bcm2836.c | 21 +++++++++++++++++++++
|
|
2 files changed, 37 insertions(+), 2 deletions(-)
|
|
|
|
--- a/drivers/irqchip/irq-bcm2835.c
|
|
+++ b/drivers/irqchip/irq-bcm2835.c
|
|
@@ -154,10 +154,23 @@ static void armctrl_unmask_irq(struct ir
|
|
}
|
|
}
|
|
|
|
+#ifdef CONFIG_ARM64
|
|
+void bcm2836_arm_irqchip_spin_gpu_irq(void);
|
|
+
|
|
+static void armctrl_ack_irq(struct irq_data *d)
|
|
+{
|
|
+ bcm2836_arm_irqchip_spin_gpu_irq();
|
|
+}
|
|
+
|
|
+#endif
|
|
+
|
|
static struct irq_chip armctrl_chip = {
|
|
.name = "ARMCTRL-level",
|
|
.irq_mask = armctrl_mask_irq,
|
|
- .irq_unmask = armctrl_unmask_irq
|
|
+ .irq_unmask = armctrl_unmask_irq,
|
|
+#ifdef CONFIG_ARM64
|
|
+ .irq_ack = armctrl_ack_irq
|
|
+#endif
|
|
};
|
|
|
|
static int armctrl_xlate(struct irq_domain *d, struct device_node *ctrlr,
|
|
@@ -330,7 +343,8 @@ static void bcm2836_chained_handle_irq(s
|
|
{
|
|
u32 hwirq;
|
|
|
|
- while ((hwirq = get_next_armctrl_hwirq()) != ~0)
|
|
+ hwirq = get_next_armctrl_hwirq();
|
|
+ if (hwirq != ~0)
|
|
generic_handle_domain_irq(intc.domain, hwirq);
|
|
}
|
|
|
|
--- a/drivers/irqchip/irq-bcm2836.c
|
|
+++ b/drivers/irqchip/irq-bcm2836.c
|
|
@@ -87,6 +87,27 @@ static void bcm2836_arm_irqchip_unmask_g
|
|
{
|
|
}
|
|
|
|
+#ifdef CONFIG_ARM64
|
|
+
|
|
+void bcm2836_arm_irqchip_spin_gpu_irq(void)
|
|
+{
|
|
+ u32 i;
|
|
+ void __iomem *gpurouting = (intc.base + LOCAL_GPU_ROUTING);
|
|
+ u32 routing_val = readl(gpurouting);
|
|
+
|
|
+ for (i = 1; i <= 3; i++) {
|
|
+ u32 new_routing_val = (routing_val + i) & 3;
|
|
+
|
|
+ if (cpu_active(new_routing_val)) {
|
|
+ writel(new_routing_val, gpurouting);
|
|
+ return;
|
|
+ }
|
|
+ }
|
|
+}
|
|
+EXPORT_SYMBOL(bcm2836_arm_irqchip_spin_gpu_irq);
|
|
+
|
|
+#endif
|
|
+
|
|
static struct irq_chip bcm2836_arm_irqchip_gpu = {
|
|
.name = "bcm2836-gpu",
|
|
.irq_mask = bcm2836_arm_irqchip_mask_gpu_irq,
|