diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-12-15 14:52:16 -0300 |
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committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-12-15 14:52:16 -0300 |
commit | 8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch) | |
tree | e9891aa6c295060d065adffd610c4f49ecf884f3 /arch/mips/kernel/i8259.c | |
parent | a71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff) |
Linux-libre 4.3.2-gnu
Diffstat (limited to 'arch/mips/kernel/i8259.c')
-rw-r--r-- | arch/mips/kernel/i8259.c | 384 |
1 files changed, 0 insertions, 384 deletions
diff --git a/arch/mips/kernel/i8259.c b/arch/mips/kernel/i8259.c deleted file mode 100644 index 74f675281..000000000 --- a/arch/mips/kernel/i8259.c +++ /dev/null @@ -1,384 +0,0 @@ -/* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Code to handle x86 style IRQs plus some generic interrupt stuff. - * - * Copyright (C) 1992 Linus Torvalds - * Copyright (C) 1994 - 2000 Ralf Baechle - */ -#include <linux/delay.h> -#include <linux/init.h> -#include <linux/ioport.h> -#include <linux/interrupt.h> -#include <linux/irqdomain.h> -#include <linux/kernel.h> -#include <linux/of_irq.h> -#include <linux/spinlock.h> -#include <linux/syscore_ops.h> -#include <linux/irq.h> - -#include <asm/i8259.h> -#include <asm/io.h> - -#include "../../drivers/irqchip/irqchip.h" - -/* - * This is the 'legacy' 8259A Programmable Interrupt Controller, - * present in the majority of PC/AT boxes. - * plus some generic x86 specific things if generic specifics makes - * any sense at all. - * this file should become arch/i386/kernel/irq.c when the old irq.c - * moves to arch independent land - */ - -static int i8259A_auto_eoi = -1; -DEFINE_RAW_SPINLOCK(i8259A_lock); -static void disable_8259A_irq(struct irq_data *d); -static void enable_8259A_irq(struct irq_data *d); -static void mask_and_ack_8259A(struct irq_data *d); -static void init_8259A(int auto_eoi); - -static struct irq_chip i8259A_chip = { - .name = "XT-PIC", - .irq_mask = disable_8259A_irq, - .irq_disable = disable_8259A_irq, - .irq_unmask = enable_8259A_irq, - .irq_mask_ack = mask_and_ack_8259A, -}; - -/* - * 8259A PIC functions to handle ISA devices: - */ - -/* - * This contains the irq mask for both 8259A irq controllers, - */ -static unsigned int cached_irq_mask = 0xffff; - -#define cached_master_mask (cached_irq_mask) -#define cached_slave_mask (cached_irq_mask >> 8) - -static void disable_8259A_irq(struct irq_data *d) -{ - unsigned int mask, irq = d->irq - I8259A_IRQ_BASE; - unsigned long flags; - - mask = 1 << irq; - raw_spin_lock_irqsave(&i8259A_lock, flags); - cached_irq_mask |= mask; - if (irq & 8) - outb(cached_slave_mask, PIC_SLAVE_IMR); - else - outb(cached_master_mask, PIC_MASTER_IMR); - raw_spin_unlock_irqrestore(&i8259A_lock, flags); -} - -static void enable_8259A_irq(struct irq_data *d) -{ - unsigned int mask, irq = d->irq - I8259A_IRQ_BASE; - unsigned long flags; - - mask = ~(1 << irq); - raw_spin_lock_irqsave(&i8259A_lock, flags); - cached_irq_mask &= mask; - if (irq & 8) - outb(cached_slave_mask, PIC_SLAVE_IMR); - else - outb(cached_master_mask, PIC_MASTER_IMR); - raw_spin_unlock_irqrestore(&i8259A_lock, flags); -} - -int i8259A_irq_pending(unsigned int irq) -{ - unsigned int mask; - unsigned long flags; - int ret; - - irq -= I8259A_IRQ_BASE; - mask = 1 << irq; - raw_spin_lock_irqsave(&i8259A_lock, flags); - if (irq < 8) - ret = inb(PIC_MASTER_CMD) & mask; - else - ret = inb(PIC_SLAVE_CMD) & (mask >> 8); - raw_spin_unlock_irqrestore(&i8259A_lock, flags); - - return ret; -} - -void make_8259A_irq(unsigned int irq) -{ - disable_irq_nosync(irq); - irq_set_chip_and_handler(irq, &i8259A_chip, handle_level_irq); - enable_irq(irq); -} - -/* - * This function assumes to be called rarely. Switching between - * 8259A registers is slow. - * This has to be protected by the irq controller spinlock - * before being called. - */ -static inline int i8259A_irq_real(unsigned int irq) -{ - int value; - int irqmask = 1 << irq; - - if (irq < 8) { - outb(0x0B, PIC_MASTER_CMD); /* ISR register */ - value = inb(PIC_MASTER_CMD) & irqmask; - outb(0x0A, PIC_MASTER_CMD); /* back to the IRR register */ - return value; - } - outb(0x0B, PIC_SLAVE_CMD); /* ISR register */ - value = inb(PIC_SLAVE_CMD) & (irqmask >> 8); - outb(0x0A, PIC_SLAVE_CMD); /* back to the IRR register */ - return value; -} - -/* - * Careful! The 8259A is a fragile beast, it pretty - * much _has_ to be done exactly like this (mask it - * first, _then_ send the EOI, and the order of EOI - * to the two 8259s is important! - */ -static void mask_and_ack_8259A(struct irq_data *d) -{ - unsigned int irqmask, irq = d->irq - I8259A_IRQ_BASE; - unsigned long flags; - - irqmask = 1 << irq; - raw_spin_lock_irqsave(&i8259A_lock, flags); - /* - * Lightweight spurious IRQ detection. We do not want - * to overdo spurious IRQ handling - it's usually a sign - * of hardware problems, so we only do the checks we can - * do without slowing down good hardware unnecessarily. - * - * Note that IRQ7 and IRQ15 (the two spurious IRQs - * usually resulting from the 8259A-1|2 PICs) occur - * even if the IRQ is masked in the 8259A. Thus we - * can check spurious 8259A IRQs without doing the - * quite slow i8259A_irq_real() call for every IRQ. - * This does not cover 100% of spurious interrupts, - * but should be enough to warn the user that there - * is something bad going on ... - */ - if (cached_irq_mask & irqmask) - goto spurious_8259A_irq; - cached_irq_mask |= irqmask; - -handle_real_irq: - if (irq & 8) { - inb(PIC_SLAVE_IMR); /* DUMMY - (do we need this?) */ - outb(cached_slave_mask, PIC_SLAVE_IMR); - outb(0x60+(irq&7), PIC_SLAVE_CMD);/* 'Specific EOI' to slave */ - outb(0x60+PIC_CASCADE_IR, PIC_MASTER_CMD); /* 'Specific EOI' to master-IRQ2 */ - } else { - inb(PIC_MASTER_IMR); /* DUMMY - (do we need this?) */ - outb(cached_master_mask, PIC_MASTER_IMR); - outb(0x60+irq, PIC_MASTER_CMD); /* 'Specific EOI to master */ - } - raw_spin_unlock_irqrestore(&i8259A_lock, flags); - return; - -spurious_8259A_irq: - /* - * this is the slow path - should happen rarely. - */ - if (i8259A_irq_real(irq)) - /* - * oops, the IRQ _is_ in service according to the - * 8259A - not spurious, go handle it. - */ - goto handle_real_irq; - - { - static int spurious_irq_mask; - /* - * At this point we can be sure the IRQ is spurious, - * lets ACK and report it. [once per IRQ] - */ - if (!(spurious_irq_mask & irqmask)) { - printk(KERN_DEBUG "spurious 8259A interrupt: IRQ%d.\n", irq); - spurious_irq_mask |= irqmask; - } - atomic_inc(&irq_err_count); - /* - * Theoretically we do not have to handle this IRQ, - * but in Linux this does not cause problems and is - * simpler for us. - */ - goto handle_real_irq; - } -} - -static void i8259A_resume(void) -{ - if (i8259A_auto_eoi >= 0) - init_8259A(i8259A_auto_eoi); -} - -static void i8259A_shutdown(void) -{ - /* Put the i8259A into a quiescent state that - * the kernel initialization code can get it - * out of. - */ - if (i8259A_auto_eoi >= 0) { - outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */ - outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */ - } -} - -static struct syscore_ops i8259_syscore_ops = { - .resume = i8259A_resume, - .shutdown = i8259A_shutdown, -}; - -static int __init i8259A_init_sysfs(void) -{ - register_syscore_ops(&i8259_syscore_ops); - return 0; -} - -device_initcall(i8259A_init_sysfs); - -static void init_8259A(int auto_eoi) -{ - unsigned long flags; - - i8259A_auto_eoi = auto_eoi; - - raw_spin_lock_irqsave(&i8259A_lock, flags); - - outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */ - outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */ - - /* - * outb_p - this has to work on a wide range of PC hardware. - */ - outb_p(0x11, PIC_MASTER_CMD); /* ICW1: select 8259A-1 init */ - outb_p(I8259A_IRQ_BASE + 0, PIC_MASTER_IMR); /* ICW2: 8259A-1 IR0 mapped to I8259A_IRQ_BASE + 0x00 */ - outb_p(1U << PIC_CASCADE_IR, PIC_MASTER_IMR); /* 8259A-1 (the master) has a slave on IR2 */ - if (auto_eoi) /* master does Auto EOI */ - outb_p(MASTER_ICW4_DEFAULT | PIC_ICW4_AEOI, PIC_MASTER_IMR); - else /* master expects normal EOI */ - outb_p(MASTER_ICW4_DEFAULT, PIC_MASTER_IMR); - - outb_p(0x11, PIC_SLAVE_CMD); /* ICW1: select 8259A-2 init */ - outb_p(I8259A_IRQ_BASE + 8, PIC_SLAVE_IMR); /* ICW2: 8259A-2 IR0 mapped to I8259A_IRQ_BASE + 0x08 */ - outb_p(PIC_CASCADE_IR, PIC_SLAVE_IMR); /* 8259A-2 is a slave on master's IR2 */ - outb_p(SLAVE_ICW4_DEFAULT, PIC_SLAVE_IMR); /* (slave's support for AEOI in flat mode is to be investigated) */ - if (auto_eoi) - /* - * In AEOI mode we just have to mask the interrupt - * when acking. - */ - i8259A_chip.irq_mask_ack = disable_8259A_irq; - else - i8259A_chip.irq_mask_ack = mask_and_ack_8259A; - - udelay(100); /* wait for 8259A to initialize */ - - outb(cached_master_mask, PIC_MASTER_IMR); /* restore master IRQ mask */ - outb(cached_slave_mask, PIC_SLAVE_IMR); /* restore slave IRQ mask */ - - raw_spin_unlock_irqrestore(&i8259A_lock, flags); -} - -/* - * IRQ2 is cascade interrupt to second interrupt controller - */ -static struct irqaction irq2 = { - .handler = no_action, - .name = "cascade", - .flags = IRQF_NO_THREAD, -}; - -static struct resource pic1_io_resource = { - .name = "pic1", - .start = PIC_MASTER_CMD, - .end = PIC_MASTER_IMR, - .flags = IORESOURCE_BUSY -}; - -static struct resource pic2_io_resource = { - .name = "pic2", - .start = PIC_SLAVE_CMD, - .end = PIC_SLAVE_IMR, - .flags = IORESOURCE_BUSY -}; - -static int i8259A_irq_domain_map(struct irq_domain *d, unsigned int virq, - irq_hw_number_t hw) -{ - irq_set_chip_and_handler(virq, &i8259A_chip, handle_level_irq); - irq_set_probe(virq); - return 0; -} - -static struct irq_domain_ops i8259A_ops = { - .map = i8259A_irq_domain_map, - .xlate = irq_domain_xlate_onecell, -}; - -/* - * On systems with i8259-style interrupt controllers we assume for - * driver compatibility reasons interrupts 0 - 15 to be the i8259 - * interrupts even if the hardware uses a different interrupt numbering. - */ -struct irq_domain * __init __init_i8259_irqs(struct device_node *node) -{ - struct irq_domain *domain; - - insert_resource(&ioport_resource, &pic1_io_resource); - insert_resource(&ioport_resource, &pic2_io_resource); - - init_8259A(0); - - domain = irq_domain_add_legacy(node, 16, I8259A_IRQ_BASE, 0, - &i8259A_ops, NULL); - if (!domain) - panic("Failed to add i8259 IRQ domain"); - - setup_irq(I8259A_IRQ_BASE + PIC_CASCADE_IR, &irq2); - return domain; -} - -void __init init_i8259_irqs(void) -{ - __init_i8259_irqs(NULL); -} - -static void i8259_irq_dispatch(unsigned int irq, struct irq_desc *desc) -{ - struct irq_domain *domain = irq_get_handler_data(irq); - int hwirq = i8259_irq(); - - if (hwirq < 0) - return; - - irq = irq_linear_revmap(domain, hwirq); - generic_handle_irq(irq); -} - -int __init i8259_of_init(struct device_node *node, struct device_node *parent) -{ - struct irq_domain *domain; - unsigned int parent_irq; - - parent_irq = irq_of_parse_and_map(node, 0); - if (!parent_irq) { - pr_err("Failed to map i8259 parent IRQ\n"); - return -ENODEV; - } - - domain = __init_i8259_irqs(node); - irq_set_handler_data(parent_irq, domain); - irq_set_chained_handler(parent_irq, i8259_irq_dispatch); - return 0; -} -IRQCHIP_DECLARE(i8259, "intel,i8259", i8259_of_init); |