diff options
author | David Howells <dhowells@redhat.com> | 2010-10-27 16:28:58 (GMT) |
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committer | David Howells <dhowells@redhat.com> | 2010-10-27 16:28:58 (GMT) |
commit | 6044cf1d9426dfd5cdc1e7b9cf8eaed6418e1ff6 (patch) | |
tree | 3f6f209d37328ce1635df8f5d0b5df1cef1afe30 /arch/mn10300/unit-asb2364/irq-fpga.c | |
parent | 730c1fad0ee22a170d2ee76a904709ee304931c0 (diff) | |
download | linux-6044cf1d9426dfd5cdc1e7b9cf8eaed6418e1ff6.tar.xz |
MN10300: ASB2364: Handle the IRQ multiplexer in the FPGA
Handle the IRQ multiplexer in the FPGA by implementing a cascade interrupt
driver for it.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'arch/mn10300/unit-asb2364/irq-fpga.c')
-rw-r--r-- | arch/mn10300/unit-asb2364/irq-fpga.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/arch/mn10300/unit-asb2364/irq-fpga.c b/arch/mn10300/unit-asb2364/irq-fpga.c new file mode 100644 index 0000000..fcf2975 --- /dev/null +++ b/arch/mn10300/unit-asb2364/irq-fpga.c @@ -0,0 +1,96 @@ +/* ASB2364 FPGA interrupt multiplexing + * + * Copyright (C) 2010 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <unit/fpga-regs.h> + +/* + * FPGA PIC operations + */ +static void asb2364_fpga_mask(unsigned int irq) +{ + ASB2364_FPGA_REG_MASK(irq - NR_CPU_IRQS) = 0x0001; + SyncExBus(); +} + +static void asb2364_fpga_ack(unsigned int irq) +{ + ASB2364_FPGA_REG_IRQ(irq - NR_CPU_IRQS) = 0x0001; + SyncExBus(); +} + +static void asb2364_fpga_mask_ack(unsigned int irq) +{ + ASB2364_FPGA_REG_MASK(irq - NR_CPU_IRQS) = 0x0001; + SyncExBus(); + ASB2364_FPGA_REG_IRQ(irq - NR_CPU_IRQS) = 0x0001; + SyncExBus(); +} + +static void asb2364_fpga_unmask(unsigned int irq) +{ + ASB2364_FPGA_REG_MASK(irq - NR_CPU_IRQS) = 0x0000; + SyncExBus(); +} + +static struct irq_chip asb2364_fpga_pic = { + .name = "fpga", + .ack = asb2364_fpga_ack, + .mask = asb2364_fpga_mask, + .mask_ack = asb2364_fpga_mask_ack, + .unmask = asb2364_fpga_unmask, +}; + +/* + * FPGA PIC interrupt handler + */ +static irqreturn_t fpga_interrupt(int irq, void *_mask) +{ + if ((ASB2364_FPGA_REG_IRQ_LAN & 0x0001) != 0x0001) + generic_handle_irq(FPGA_LAN_IRQ); + if ((ASB2364_FPGA_REG_IRQ_UART & 0x0001) != 0x0001) + generic_handle_irq(FPGA_UART_IRQ); + if ((ASB2364_FPGA_REG_IRQ_I2C & 0x0001) != 0x0001) + generic_handle_irq(FPGA_I2C_IRQ); + if ((ASB2364_FPGA_REG_IRQ_USB & 0x0001) != 0x0001) + generic_handle_irq(FPGA_USB_IRQ); + if ((ASB2364_FPGA_REG_IRQ_FPGA & 0x0001) != 0x0001) + generic_handle_irq(FPGA_FPGA_IRQ); + + return IRQ_HANDLED; +} + +/* + * Define an interrupt action for each FPGA PIC output + */ +static struct irqaction fpga_irq[] = { + [0] = { + .handler = fpga_interrupt, + .flags = IRQF_DISABLED | IRQF_SHARED, + .name = "fpga", + }, +}; + +/* + * Initialise the FPGA's PIC + */ +void __init irq_fpga_init(void) +{ + int irq; + + for (irq = NR_CPU_IRQS; irq < NR_IRQS; irq++) + set_irq_chip_and_handler(irq, &asb2364_fpga_pic, handle_level_irq); + + /* the FPGA drives the XIRQ1 input on the CPU PIC */ + setup_irq(XIRQ1, &fpga_irq[0]); +} |