diff options
Diffstat (limited to 'arch/mips/lantiq/irq.c')
| -rw-r--r-- | arch/mips/lantiq/irq.c | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/arch/mips/lantiq/irq.c b/arch/mips/lantiq/irq.c new file mode 100644 index 00000000000..fc89795cafd --- /dev/null +++ b/arch/mips/lantiq/irq.c @@ -0,0 +1,326 @@ +/* + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * Copyright (C) 2010 John Crispin <blogic@openwrt.org> + * Copyright (C) 2010 Thomas Langer <thomas.langer@lantiq.com> + */ + +#include <linux/interrupt.h> +#include <linux/ioport.h> + +#include <asm/bootinfo.h> +#include <asm/irq_cpu.h> + +#include <lantiq_soc.h> +#include <irq.h> + +/* register definitions */ +#define LTQ_ICU_IM0_ISR 0x0000 +#define LTQ_ICU_IM0_IER 0x0008 +#define LTQ_ICU_IM0_IOSR 0x0010 +#define LTQ_ICU_IM0_IRSR 0x0018 +#define LTQ_ICU_IM0_IMR 0x0020 +#define LTQ_ICU_IM1_ISR 0x0028 +#define LTQ_ICU_OFFSET (LTQ_ICU_IM1_ISR - LTQ_ICU_IM0_ISR) + +#define LTQ_EIU_EXIN_C 0x0000 +#define LTQ_EIU_EXIN_INIC 0x0004 +#define LTQ_EIU_EXIN_INEN 0x000C + +/* irq numbers used by the external interrupt unit (EIU) */ +#define LTQ_EIU_IR0 (INT_NUM_IM4_IRL0 + 30) +#define LTQ_EIU_IR1 (INT_NUM_IM3_IRL0 + 31) +#define LTQ_EIU_IR2 (INT_NUM_IM1_IRL0 + 26) +#define LTQ_EIU_IR3 INT_NUM_IM1_IRL0 +#define LTQ_EIU_IR4 (INT_NUM_IM1_IRL0 + 1) +#define LTQ_EIU_IR5 (INT_NUM_IM1_IRL0 + 2) +#define LTQ_EIU_IR6 (INT_NUM_IM2_IRL0 + 30) + +#define MAX_EIU 6 + +/* irqs generated by device attached to the EBU need to be acked in + * a special manner + */ +#define LTQ_ICU_EBU_IRQ 22 + +#define ltq_icu_w32(x, y) ltq_w32((x), ltq_icu_membase + (y)) +#define ltq_icu_r32(x) ltq_r32(ltq_icu_membase + (x)) + +#define ltq_eiu_w32(x, y) ltq_w32((x), ltq_eiu_membase + (y)) +#define ltq_eiu_r32(x) ltq_r32(ltq_eiu_membase + (x)) + +static unsigned short ltq_eiu_irq[MAX_EIU] = { + LTQ_EIU_IR0, + LTQ_EIU_IR1, + LTQ_EIU_IR2, + LTQ_EIU_IR3, + LTQ_EIU_IR4, + LTQ_EIU_IR5, +}; + +static struct resource ltq_icu_resource = { + .name = "icu", + .start = LTQ_ICU_BASE_ADDR, + .end = LTQ_ICU_BASE_ADDR + LTQ_ICU_SIZE - 1, + .flags = IORESOURCE_MEM, +}; + +static struct resource ltq_eiu_resource = { + .name = "eiu", + .start = LTQ_EIU_BASE_ADDR, + .end = LTQ_EIU_BASE_ADDR + LTQ_ICU_SIZE - 1, + .flags = IORESOURCE_MEM, +}; + +static void __iomem *ltq_icu_membase; +static void __iomem *ltq_eiu_membase; + +void ltq_disable_irq(struct irq_data *d) +{ + u32 ier = LTQ_ICU_IM0_IER; + int irq_nr = d->irq - INT_NUM_IRQ0; + + ier += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET); + irq_nr %= INT_NUM_IM_OFFSET; + ltq_icu_w32(ltq_icu_r32(ier) & ~(1 << irq_nr), ier); +} + +void ltq_mask_and_ack_irq(struct irq_data *d) +{ + u32 ier = LTQ_ICU_IM0_IER; + u32 isr = LTQ_ICU_IM0_ISR; + int irq_nr = d->irq - INT_NUM_IRQ0; + + ier += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET); + isr += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET); + irq_nr %= INT_NUM_IM_OFFSET; + ltq_icu_w32(ltq_icu_r32(ier) & ~(1 << irq_nr), ier); + ltq_icu_w32((1 << irq_nr), isr); +} + +static void ltq_ack_irq(struct irq_data *d) +{ + u32 isr = LTQ_ICU_IM0_ISR; + int irq_nr = d->irq - INT_NUM_IRQ0; + + isr += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET); + irq_nr %= INT_NUM_IM_OFFSET; + ltq_icu_w32((1 << irq_nr), isr); +} + +void ltq_enable_irq(struct irq_data *d) +{ + u32 ier = LTQ_ICU_IM0_IER; + int irq_nr = d->irq - INT_NUM_IRQ0; + + ier += LTQ_ICU_OFFSET * (irq_nr / INT_NUM_IM_OFFSET); + irq_nr %= INT_NUM_IM_OFFSET; + ltq_icu_w32(ltq_icu_r32(ier) | (1 << irq_nr), ier); +} + +static unsigned int ltq_startup_eiu_irq(struct irq_data *d) +{ + int i; + int irq_nr = d->irq - INT_NUM_IRQ0; + + ltq_enable_irq(d); + for (i = 0; i < MAX_EIU; i++) { + if (irq_nr == ltq_eiu_irq[i]) { + /* low level - we should really handle set_type */ + ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_C) | + (0x6 << (i * 4)), LTQ_EIU_EXIN_C); + /* clear all pending */ + ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INIC) & ~(1 << i), + LTQ_EIU_EXIN_INIC); + /* enable */ + ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) | (1 << i), + LTQ_EIU_EXIN_INEN); + break; + } + } + + return 0; +} + +static void ltq_shutdown_eiu_irq(struct irq_data *d) +{ + int i; + int irq_nr = d->irq - INT_NUM_IRQ0; + + ltq_disable_irq(d); + for (i = 0; i < MAX_EIU; i++) { + if (irq_nr == ltq_eiu_irq[i]) { + /* disable */ + ltq_eiu_w32(ltq_eiu_r32(LTQ_EIU_EXIN_INEN) & ~(1 << i), + LTQ_EIU_EXIN_INEN); + break; + } + } +} + +static struct irq_chip ltq_irq_type = { + "icu", + .irq_enable = ltq_enable_irq, + .irq_disable = ltq_disable_irq, + .irq_unmask = ltq_enable_irq, + .irq_ack = ltq_ack_irq, + .irq_mask = ltq_disable_irq, + .irq_mask_ack = ltq_mask_and_ack_irq, +}; + +static struct irq_chip ltq_eiu_type = { + "eiu", + .irq_startup = ltq_startup_eiu_irq, + .irq_shutdown = ltq_shutdown_eiu_irq, + .irq_enable = ltq_enable_irq, + .irq_disable = ltq_disable_irq, + .irq_unmask = ltq_enable_irq, + .irq_ack = ltq_ack_irq, + .irq_mask = ltq_disable_irq, + .irq_mask_ack = ltq_mask_and_ack_irq, +}; + +static void ltq_hw_irqdispatch(int module) +{ + u32 irq; + + irq = ltq_icu_r32(LTQ_ICU_IM0_IOSR + (module * LTQ_ICU_OFFSET)); + if (irq == 0) + return; + + /* silicon bug causes only the msb set to 1 to be valid. all + * other bits might be bogus + */ + irq = __fls(irq); + do_IRQ((int)irq + INT_NUM_IM0_IRL0 + (INT_NUM_IM_OFFSET * module)); + + /* if this is a EBU irq, we need to ack it or get a deadlock */ + if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0)) + ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_ISTAT) | 0x10, + LTQ_EBU_PCC_ISTAT); +} + +#define DEFINE_HWx_IRQDISPATCH(x) \ + static void ltq_hw ## x ## _irqdispatch(void) \ + { \ + ltq_hw_irqdispatch(x); \ + } +DEFINE_HWx_IRQDISPATCH(0) +DEFINE_HWx_IRQDISPATCH(1) +DEFINE_HWx_IRQDISPATCH(2) +DEFINE_HWx_IRQDISPATCH(3) +DEFINE_HWx_IRQDISPATCH(4) + +static void ltq_hw5_irqdispatch(void) +{ + do_IRQ(MIPS_CPU_TIMER_IRQ); +} + +asmlinkage void plat_irq_dispatch(void) +{ + unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM; + unsigned int i; + + if (pending & CAUSEF_IP7) { + do_IRQ(MIPS_CPU_TIMER_IRQ); + goto out; + } else { + for (i = 0; i < 5; i++) { + if (pending & (CAUSEF_IP2 << i)) { + ltq_hw_irqdispatch(i); + goto out; + } + } + } + pr_alert("Spurious IRQ: CAUSE=0x%08x\n", read_c0_status()); + +out: + return; +} + +static struct irqaction cascade = { + .handler = no_action, + .flags = IRQF_DISABLED, + .name = "cascade", +}; + +void __init arch_init_irq(void) +{ + int i; + + if (insert_resource(&iomem_resource, <q_icu_resource) < 0) + panic("Failed to insert icu memory\n"); + + if (request_mem_region(ltq_icu_resource.start, + resource_size(<q_icu_resource), "icu") < 0) + panic("Failed to request icu memory\n"); + + ltq_icu_membase = ioremap_nocache(ltq_icu_resource.start, + resource_size(<q_icu_resource)); + if (!ltq_icu_membase) + panic("Failed to remap icu memory\n"); + + if (insert_resource(&iomem_resource, <q_eiu_resource) < 0) + panic("Failed to insert eiu memory\n"); + + if (request_mem_region(ltq_eiu_resource.start, + resource_size(<q_eiu_resource), "eiu") < 0) + panic("Failed to request eiu memory\n"); + + ltq_eiu_membase = ioremap_nocache(ltq_eiu_resource.start, + resource_size(<q_eiu_resource)); + if (!ltq_eiu_membase) + panic("Failed to remap eiu memory\n"); + + /* make sure all irqs are turned off by default */ + for (i = 0; i < 5; i++) + ltq_icu_w32(0, LTQ_ICU_IM0_IER + (i * LTQ_ICU_OFFSET)); + + /* clear all possibly pending interrupts */ + ltq_icu_w32(~0, LTQ_ICU_IM0_ISR + (i * LTQ_ICU_OFFSET)); + + mips_cpu_irq_init(); + + for (i = 2; i <= 6; i++) + setup_irq(i, &cascade); + + if (cpu_has_vint) { + pr_info("Setting up vectored interrupts\n"); + set_vi_handler(2, ltq_hw0_irqdispatch); + set_vi_handler(3, ltq_hw1_irqdispatch); + set_vi_handler(4, ltq_hw2_irqdispatch); + set_vi_handler(5, ltq_hw3_irqdispatch); + set_vi_handler(6, ltq_hw4_irqdispatch); + set_vi_handler(7, ltq_hw5_irqdispatch); + } + + for (i = INT_NUM_IRQ0; + i <= (INT_NUM_IRQ0 + (5 * INT_NUM_IM_OFFSET)); i++) + if ((i == LTQ_EIU_IR0) || (i == LTQ_EIU_IR1) || + (i == LTQ_EIU_IR2)) + irq_set_chip_and_handler(i, <q_eiu_type, + handle_level_irq); + /* EIU3-5 only exist on ar9 and vr9 */ + else if (((i == LTQ_EIU_IR3) || (i == LTQ_EIU_IR4) || + (i == LTQ_EIU_IR5)) && (ltq_is_ar9() || ltq_is_vr9())) + irq_set_chip_and_handler(i, <q_eiu_type, + handle_level_irq); + else + irq_set_chip_and_handler(i, <q_irq_type, + handle_level_irq); + +#if !defined(CONFIG_MIPS_MT_SMP) && !defined(CONFIG_MIPS_MT_SMTC) + set_c0_status(IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | + IE_IRQ3 | IE_IRQ4 | IE_IRQ5); +#else + set_c0_status(IE_SW0 | IE_SW1 | IE_IRQ0 | IE_IRQ1 | + IE_IRQ2 | IE_IRQ3 | IE_IRQ4 | IE_IRQ5); +#endif +} + +unsigned int __cpuinit get_c0_compare_int(void) +{ + return CP0_LEGACY_COMPARE_IRQ; +} |