diff options
Diffstat (limited to 'arch/powerpc/sysdev/i8259.c')
| -rw-r--r-- | arch/powerpc/sysdev/i8259.c | 141 |
1 files changed, 112 insertions, 29 deletions
diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c index c2e9465871a..72c73a6105c 100644 --- a/arch/powerpc/sysdev/i8259.c +++ b/arch/powerpc/sysdev/i8259.c @@ -6,11 +6,16 @@ * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ +#undef DEBUG + #include <linux/init.h> #include <linux/ioport.h> #include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/delay.h> #include <asm/io.h> #include <asm/i8259.h> +#include <asm/prom.h> static volatile void __iomem *pci_intack; /* RO, gives us the irq vector */ @@ -20,7 +25,8 @@ static unsigned char cached_8259[2] = { 0xff, 0xff }; static DEFINE_SPINLOCK(i8259_lock); -static int i8259_pic_irq_offset; +static struct device_node *i8259_node; +static struct irq_host *i8259_host; /* * Acknowledge the IRQ using either the PCI host bridge's interrupt @@ -28,16 +34,18 @@ static int i8259_pic_irq_offset; * which is called. It should be noted that polling is broken on some * IBM and Motorola PReP boxes so we must use the int-ack feature on them. */ -int i8259_irq(struct pt_regs *regs) +unsigned int i8259_irq(struct pt_regs *regs) { int irq; - - spin_lock(&i8259_lock); + int lock = 0; /* Either int-ack or poll for the IRQ */ if (pci_intack) irq = readb(pci_intack); else { + spin_lock(&i8259_lock); + lock = 1; + /* Perform an interrupt acknowledge cycle on controller 1. */ outb(0x0C, 0x20); /* prepare for poll */ irq = inb(0x20) & 7; @@ -62,11 +70,13 @@ int i8259_irq(struct pt_regs *regs) if (!pci_intack) outb(0x0B, 0x20); /* ISR register */ if(~inb(0x20) & 0x80) - irq = -1; - } + irq = NO_IRQ; + } else if (irq == 0xff) + irq = NO_IRQ; - spin_unlock(&i8259_lock); - return irq + i8259_pic_irq_offset; + if (lock) + spin_unlock(&i8259_lock); + return irq; } static void i8259_mask_and_ack_irq(unsigned int irq_nr) @@ -74,7 +84,6 @@ static void i8259_mask_and_ack_irq(unsigned int irq_nr) unsigned long flags; spin_lock_irqsave(&i8259_lock, flags); - irq_nr -= i8259_pic_irq_offset; if (irq_nr > 7) { cached_A1 |= 1 << (irq_nr-8); inb(0xA1); /* DUMMY */ @@ -100,8 +109,9 @@ static void i8259_mask_irq(unsigned int irq_nr) { unsigned long flags; + pr_debug("i8259_mask_irq(%d)\n", irq_nr); + spin_lock_irqsave(&i8259_lock, flags); - irq_nr -= i8259_pic_irq_offset; if (irq_nr < 8) cached_21 |= 1 << irq_nr; else @@ -114,8 +124,9 @@ static void i8259_unmask_irq(unsigned int irq_nr) { unsigned long flags; + pr_debug("i8259_unmask_irq(%d)\n", irq_nr); + spin_lock_irqsave(&i8259_lock, flags); - irq_nr -= i8259_pic_irq_offset; if (irq_nr < 8) cached_21 &= ~(1 << irq_nr); else @@ -152,25 +163,84 @@ static struct resource pic_edgectrl_iores = { .flags = IORESOURCE_BUSY, }; -static struct irqaction i8259_irqaction = { - .handler = no_action, - .flags = IRQF_DISABLED, - .mask = CPU_MASK_NONE, - .name = "82c59 secondary cascade", +static int i8259_host_match(struct irq_host *h, struct device_node *node) +{ + return i8259_node == NULL || i8259_node == node; +} + +static int i8259_host_map(struct irq_host *h, unsigned int virq, + irq_hw_number_t hw, unsigned int flags) +{ + pr_debug("i8259_host_map(%d, 0x%lx)\n", virq, hw); + + /* We block the internal cascade */ + if (hw == 2) + get_irq_desc(virq)->status |= IRQ_NOREQUEST; + + /* We use the level stuff only for now, we might want to + * be more cautious here but that works for now + */ + get_irq_desc(virq)->status |= IRQ_LEVEL; + set_irq_chip_and_handler(virq, &i8259_pic, handle_level_irq); + return 0; +} + +static void i8259_host_unmap(struct irq_host *h, unsigned int virq) +{ + /* Make sure irq is masked in hardware */ + i8259_mask_irq(virq); + + /* remove chip and handler */ + set_irq_chip_and_handler(virq, NULL, NULL); + + /* Make sure it's completed */ + synchronize_irq(virq); +} + +static int i8259_host_xlate(struct irq_host *h, struct device_node *ct, + u32 *intspec, unsigned int intsize, + irq_hw_number_t *out_hwirq, unsigned int *out_flags) +{ + static unsigned char map_isa_senses[4] = { + IRQ_TYPE_LEVEL_LOW, + IRQ_TYPE_LEVEL_HIGH, + IRQ_TYPE_EDGE_FALLING, + IRQ_TYPE_EDGE_RISING, + }; + + *out_hwirq = intspec[0]; + if (intsize > 1 && intspec[1] < 4) + *out_flags = map_isa_senses[intspec[1]]; + else + *out_flags = IRQ_TYPE_NONE; + + return 0; +} + +static struct irq_host_ops i8259_host_ops = { + .match = i8259_host_match, + .map = i8259_host_map, + .unmap = i8259_host_unmap, + .xlate = i8259_host_xlate, }; -/* - * i8259_init() - * intack_addr - PCI interrupt acknowledge (real) address which will return - * the active irq from the 8259 +/**** + * i8259_init - Initialize the legacy controller + * @node: device node of the legacy PIC (can be NULL, but then, it will match + * all interrupts, so beware) + * @intack_addr: PCI interrupt acknowledge (real) address which will return + * the active irq from the 8259 */ -void __init i8259_init(unsigned long intack_addr, int offset) +void i8259_init(struct device_node *node, unsigned long intack_addr) { unsigned long flags; - int i; + /* initialize the controller */ spin_lock_irqsave(&i8259_lock, flags); - i8259_pic_irq_offset = offset; + + /* Mask all first */ + outb(0xff, 0xA1); + outb(0xff, 0x21); /* init master interrupt controller */ outb(0x11, 0x20); /* Start init sequence */ @@ -184,24 +254,36 @@ void __init i8259_init(unsigned long intack_addr, int offset) outb(0x02, 0xA1); /* edge triggered, Cascade (slave) on IRQ2 */ outb(0x01, 0xA1); /* Select 8086 mode */ + /* That thing is slow */ + udelay(100); + /* always read ISR */ outb(0x0B, 0x20); outb(0x0B, 0xA0); - /* Mask all interrupts */ + /* Unmask the internal cascade */ + cached_21 &= ~(1 << 2); + + /* Set interrupt masks */ outb(cached_A1, 0xA1); outb(cached_21, 0x21); spin_unlock_irqrestore(&i8259_lock, flags); - for (i = 0; i < NUM_ISA_INTERRUPTS; ++i) { - set_irq_chip_and_handler(offset + i, &i8259_pic, - handle_level_irq); - irq_desc[offset + i].status |= IRQ_LEVEL; + /* create a legacy host */ + if (node) + i8259_node = of_node_get(node); + i8259_host = irq_alloc_host(IRQ_HOST_MAP_LEGACY, 0, &i8259_host_ops, 0); + if (i8259_host == NULL) { + printk(KERN_ERR "i8259: failed to allocate irq host !\n"); + return; } /* reserve our resources */ - setup_irq(offset + 2, &i8259_irqaction); + /* XXX should we continue doing that ? it seems to cause problems + * with further requesting of PCI IO resources for that range... + * need to look into it. + */ request_resource(&ioport_resource, &pic1_iores); request_resource(&ioport_resource, &pic2_iores); request_resource(&ioport_resource, &pic_edgectrl_iores); @@ -209,4 +291,5 @@ void __init i8259_init(unsigned long intack_addr, int offset) if (intack_addr != 0) pci_intack = ioremap(intack_addr, 1); + printk(KERN_INFO "i8259 legacy interrupt controller initialized\n"); } |