linux-stable-rt/arch/mips/lemote/lm2e/irq.c

146 lines
3.9 KiB
C

/*
* Copyright (C) 2007 Lemote Inc. & Insititute of Computing Technology
* Author: Fuxin Zhang, zhangfx@lemote.com
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
* NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <asm/irq_cpu.h>
#include <asm/i8259.h>
#include <asm/mipsregs.h>
#include <asm/mips-boards/bonito64.h>
/*
* the first level int-handler will jump here if it is a bonito irq
*/
static void bonito_irqdispatch(void)
{
u32 int_status;
int i;
/* workaround the IO dma problem: let cpu looping to allow DMA finish */
int_status = BONITO_INTISR;
if (int_status & (1 << 10)) {
while (int_status & (1 << 10)) {
udelay(1);
int_status = BONITO_INTISR;
}
}
/* Get pending sources, masked by current enables */
int_status = BONITO_INTISR & BONITO_INTEN;
if (int_status != 0) {
i = __ffs(int_status);
int_status &= ~(1 << i);
do_IRQ(BONITO_IRQ_BASE + i);
}
}
static void i8259_irqdispatch(void)
{
int irq;
irq = i8259_irq();
if (irq >= 0) {
do_IRQ(irq);
} else {
spurious_interrupt();
}
}
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
if (pending & CAUSEF_IP7) {
do_IRQ(MIPS_CPU_IRQ_BASE + 7);
} else if (pending & CAUSEF_IP5) {
i8259_irqdispatch();
} else if (pending & CAUSEF_IP2) {
bonito_irqdispatch();
} else {
spurious_interrupt();
}
}
static struct irqaction cascade_irqaction = {
.handler = no_action,
.mask = CPU_MASK_NONE,
.name = "cascade",
};
void __init arch_init_irq(void)
{
extern void bonito_irq_init(void);
/*
* Clear all of the interrupts while we change the able around a bit.
* int-handler is not on bootstrap
*/
clear_c0_status(ST0_IM | ST0_BEV);
local_irq_disable();
/* most bonito irq should be level triggered */
BONITO_INTEDGE = BONITO_ICU_SYSTEMERR | BONITO_ICU_MASTERERR |
BONITO_ICU_RETRYERR | BONITO_ICU_MBOXES;
BONITO_INTSTEER = 0;
/*
* Mask out all interrupt by writing "1" to all bit position in
* the interrupt reset reg.
*/
BONITO_INTENCLR = ~0;
/* init all controller
* 0-15 ------> i8259 interrupt
* 16-23 ------> mips cpu interrupt
* 32-63 ------> bonito irq
*/
/* Sets the first-level interrupt dispatcher. */
mips_cpu_irq_init();
init_i8259_irqs();
bonito_irq_init();
/*
printk("GPIODATA=%x, GPIOIE=%x\n", BONITO_GPIODATA, BONITO_GPIOIE);
printk("INTEN=%x, INTSET=%x, INTCLR=%x, INTISR=%x\n",
BONITO_INTEN, BONITO_INTENSET,
BONITO_INTENCLR, BONITO_INTISR);
*/
/* bonito irq at IP2 */
setup_irq(MIPS_CPU_IRQ_BASE + 2, &cascade_irqaction);
/* 8259 irq at IP5 */
setup_irq(MIPS_CPU_IRQ_BASE + 5, &cascade_irqaction);
}