linux/drivers/irqchip/irq-ath79-cpu.c

95 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Atheros AR71xx/AR724x/AR913x specific interrupt handling
*
* Copyright (C) 2015 Alban Bedel <albeu@free.fr>
* Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
* Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
*
* Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
*/
#include <linux/interrupt.h>
#include <linux/irqchip.h>
#include <linux/of.h>
#include <asm/irq_cpu.h>
#include <asm/mach-ath79/ath79.h>
/*
* The IP2/IP3 lines are tied to a PCI/WMAC/USB device. Drivers for
* these devices typically allocate coherent DMA memory, however the
* DMA controller may still have some unsynchronized data in the FIFO.
* Issue a flush in the handlers to ensure that the driver sees
* the update.
*
* This array map the interrupt lines to the DDR write buffer channels.
*/
static unsigned irq_wb_chan[8] = {
-1, -1, -1, -1, -1, -1, -1, -1,
};
asmlinkage void plat_irq_dispatch(void)
{
unsigned long pending;
int irq;
pending = read_c0_status() & read_c0_cause() & ST0_IM;
if (!pending) {
spurious_interrupt();
return;
}
pending >>= CAUSEB_IP;
while (pending) {
irq = fls(pending) - 1;
if (irq < ARRAY_SIZE(irq_wb_chan) && irq_wb_chan[irq] != -1)
ath79_ddr_wb_flush(irq_wb_chan[irq]);
do_IRQ(MIPS_CPU_IRQ_BASE + irq);
pending &= ~BIT(irq);
}
}
static int __init ar79_cpu_intc_of_init(
struct device_node *node, struct device_node *parent)
{
int err, i, count;
/* Fill the irq_wb_chan table */
count = of_count_phandle_with_args(
node, "qca,ddr-wb-channels", "#qca,ddr-wb-channel-cells");
for (i = 0; i < count; i++) {
struct of_phandle_args args;
u32 irq = i;
of_property_read_u32_index(
node, "qca,ddr-wb-channel-interrupts", i, &irq);
if (irq >= ARRAY_SIZE(irq_wb_chan))
continue;
err = of_parse_phandle_with_args(
node, "qca,ddr-wb-channels",
"#qca,ddr-wb-channel-cells",
i, &args);
if (err)
return err;
irq_wb_chan[irq] = args.args[0];
}
return mips_cpu_irq_of_init(node, parent);
}
IRQCHIP_DECLARE(ar79_cpu_intc, "qca,ar7100-cpu-intc",
ar79_cpu_intc_of_init);
void __init ath79_cpu_irq_init(unsigned irq_wb_chan2, unsigned irq_wb_chan3)
{
irq_wb_chan[2] = irq_wb_chan2;
irq_wb_chan[3] = irq_wb_chan3;
mips_cpu_irq_init();
}