diff options
Diffstat (limited to 'arch/mips/pnx8550/common/int.c')
| -rw-r--r-- | arch/mips/pnx8550/common/int.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/arch/mips/pnx8550/common/int.c b/arch/mips/pnx8550/common/int.c new file mode 100644 index 000000000000..cfed5051dc6d --- /dev/null +++ b/arch/mips/pnx8550/common/int.c @@ -0,0 +1,236 @@ +/* + * + * Copyright (C) 2005 Embedded Alley Solutions, Inc + * Ported to 2.6. + * + * Per Hallsmark, per.hallsmark@mvista.com + * Copyright (C) 2000, 2001 MIPS Technologies, Inc. + * Copyright (C) 2001 Ralf Baechle + * + * Cleaned up and bug fixing: Pete Popov, ppopov@embeddedalley.com + * + * This program is free software; you can distribute it and/or modify it + * under the terms of the GNU General Public License (Version 2) as + * published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * 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., + * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + */ +#include <linux/compiler.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/kernel_stat.h> +#include <linux/random.h> +#include <linux/module.h> + +#include <asm/io.h> +#include <int.h> +#include <uart.h> + +/* default prio for interrupts */ +/* first one is a no-no so therefore always prio 0 (disabled) */ +static char gic_prio[PNX8550_INT_GIC_TOTINT] = { + 0, 1, 1, 1, 1, 15, 1, 1, 1, 1, // 0 - 9 + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 10 - 19 + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 20 - 29 + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 30 - 39 + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 40 - 49 + 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, // 50 - 59 + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // 60 - 69 + 1 // 70 +}; + +static void hw0_irqdispatch(int irq) +{ + /* find out which interrupt */ + irq = PNX8550_GIC_VECTOR_0 >> 3; + + if (irq == 0) { + printk("hw0_irqdispatch: irq 0, spurious interrupt?\n"); + return; + } + do_IRQ(PNX8550_INT_GIC_MIN + irq); +} + + +static void timer_irqdispatch(int irq) +{ + irq = (0x01c0 & read_c0_config7()) >> 6; + + if (unlikely(irq == 0)) { + printk("timer_irqdispatch: irq 0, spurious interrupt?\n"); + return; + } + + if (irq & 0x1) + do_IRQ(PNX8550_INT_TIMER1); + if (irq & 0x2) + do_IRQ(PNX8550_INT_TIMER2); + if (irq & 0x4) + do_IRQ(PNX8550_INT_TIMER3); +} + +asmlinkage void plat_irq_dispatch(void) +{ + unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM; + + if (pending & STATUSF_IP2) + hw0_irqdispatch(2); + else if (pending & STATUSF_IP7) { + if (read_c0_config7() & 0x01c0) + timer_irqdispatch(7); + } else + spurious_interrupt(); +} + +static inline void modify_cp0_intmask(unsigned clr_mask, unsigned set_mask) +{ + unsigned long status = read_c0_status(); + + status &= ~((clr_mask & 0xFF) << 8); + status |= (set_mask & 0xFF) << 8; + + write_c0_status(status); +} + +static inline void mask_gic_int(unsigned int irq_nr) +{ + /* interrupt disabled, bit 26(WE_ENABLE)=1 and bit 16(enable)=0 */ + PNX8550_GIC_REQ(irq_nr) = 1<<28; /* set priority to 0 */ +} + +static inline void unmask_gic_int(unsigned int irq_nr) +{ + /* set prio mask to lower four bits and enable interrupt */ + PNX8550_GIC_REQ(irq_nr) = (1<<26 | 1<<16) | (1<<28) | gic_prio[irq_nr]; +} + +static inline void mask_irq(unsigned int irq_nr) +{ + if ((PNX8550_INT_CP0_MIN <= irq_nr) && (irq_nr <= PNX8550_INT_CP0_MAX)) { + modify_cp0_intmask(1 << irq_nr, 0); + } else if ((PNX8550_INT_GIC_MIN <= irq_nr) && + (irq_nr <= PNX8550_INT_GIC_MAX)) { + mask_gic_int(irq_nr - PNX8550_INT_GIC_MIN); + } else if ((PNX8550_INT_TIMER_MIN <= irq_nr) && + (irq_nr <= PNX8550_INT_TIMER_MAX)) { + modify_cp0_intmask(1 << 7, 0); + } else { + printk("mask_irq: irq %d doesn't exist!\n", irq_nr); + } +} + +static inline void unmask_irq(unsigned int irq_nr) +{ + if ((PNX8550_INT_CP0_MIN <= irq_nr) && (irq_nr <= PNX8550_INT_CP0_MAX)) { + modify_cp0_intmask(0, 1 << irq_nr); + } else if ((PNX8550_INT_GIC_MIN <= irq_nr) && + (irq_nr <= PNX8550_INT_GIC_MAX)) { + unmask_gic_int(irq_nr - PNX8550_INT_GIC_MIN); + } else if ((PNX8550_INT_TIMER_MIN <= irq_nr) && + (irq_nr <= PNX8550_INT_TIMER_MAX)) { + modify_cp0_intmask(0, 1 << 7); + } else { + printk("mask_irq: irq %d doesn't exist!\n", irq_nr); + } +} + +int pnx8550_set_gic_priority(int irq, int priority) +{ + int gic_irq = irq-PNX8550_INT_GIC_MIN; + int prev_priority = PNX8550_GIC_REQ(gic_irq) & 0xf; + + gic_prio[gic_irq] = priority; + PNX8550_GIC_REQ(gic_irq) |= (0x10000000 | gic_prio[gic_irq]); + + return prev_priority; +} + +static struct irq_chip level_irq_type = { + .name = "PNX Level IRQ", + .ack = mask_irq, + .mask = mask_irq, + .mask_ack = mask_irq, + .unmask = unmask_irq, +}; + +static struct irqaction gic_action = { + .handler = no_action, + .flags = IRQF_DISABLED, + .name = "GIC", +}; + +static struct irqaction timer_action = { + .handler = no_action, + .flags = IRQF_DISABLED | IRQF_TIMER, + .name = "Timer", +}; + +void __init arch_init_irq(void) +{ + int i; + int configPR; + + for (i = 0; i < PNX8550_INT_CP0_TOTINT; i++) { + set_irq_chip_and_handler(i, &level_irq_type, handle_level_irq); + mask_irq(i); /* mask the irq just in case */ + } + + /* init of GIC/IPC interrupts */ + /* should be done before cp0 since cp0 init enables the GIC int */ + for (i = PNX8550_INT_GIC_MIN; i <= PNX8550_INT_GIC_MAX; i++) { + int gic_int_line = i - PNX8550_INT_GIC_MIN; + if (gic_int_line == 0 ) + continue; // don't fiddle with int 0 + /* + * enable change of TARGET, ENABLE and ACTIVE_LOW bits + * set TARGET 0 to route through hw0 interrupt + * set ACTIVE_LOW 0 active high (correct?) + * + * We really should setup an interrupt description table + * to do this nicely. + * Note, PCI INTA is active low on the bus, but inverted + * in the GIC, so to us it's active high. + */ + PNX8550_GIC_REQ(i - PNX8550_INT_GIC_MIN) = 0x1E000000; + + /* mask/priority is still 0 so we will not get any + * interrupts until it is unmasked */ + + set_irq_chip_and_handler(i, &level_irq_type, handle_level_irq); + } + + /* Priority level 0 */ + PNX8550_GIC_PRIMASK_0 = PNX8550_GIC_PRIMASK_1 = 0; + + /* Set int vector table address */ + PNX8550_GIC_VECTOR_0 = PNX8550_GIC_VECTOR_1 = 0; + + set_irq_chip_and_handler(MIPS_CPU_GIC_IRQ, &level_irq_type, + handle_level_irq); + setup_irq(MIPS_CPU_GIC_IRQ, &gic_action); + + /* init of Timer interrupts */ + for (i = PNX8550_INT_TIMER_MIN; i <= PNX8550_INT_TIMER_MAX; i++) + set_irq_chip_and_handler(i, &level_irq_type, handle_level_irq); + + /* Stop Timer 1-3 */ + configPR = read_c0_config7(); + configPR |= 0x00000038; + write_c0_config7(configPR); + + set_irq_chip_and_handler(MIPS_CPU_TIMER_IRQ, &level_irq_type, + handle_level_irq); + setup_irq(MIPS_CPU_TIMER_IRQ, &timer_action); +} + +EXPORT_SYMBOL(pnx8550_set_gic_priority); |