| /* |
| * arch/powerpc/sysdev/uic.c |
| * |
| * IBM PowerPC 4xx Universal Interrupt Controller |
| * |
| * Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation. |
| * |
| * 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. |
| */ |
| #include <linux/kernel.h> |
| #include <linux/init.h> |
| #include <linux/errno.h> |
| #include <linux/reboot.h> |
| #include <linux/slab.h> |
| #include <linux/stddef.h> |
| #include <linux/sched.h> |
| #include <linux/signal.h> |
| #include <linux/device.h> |
| #include <linux/spinlock.h> |
| #include <linux/irq.h> |
| #include <linux/interrupt.h> |
| #include <linux/kernel_stat.h> |
| #include <asm/irq.h> |
| #include <asm/io.h> |
| #include <asm/prom.h> |
| #include <asm/dcr.h> |
| |
| #define NR_UIC_INTS 32 |
| |
| #define UIC_SR 0x0 |
| #define UIC_ER 0x2 |
| #define UIC_CR 0x3 |
| #define UIC_PR 0x4 |
| #define UIC_TR 0x5 |
| #define UIC_MSR 0x6 |
| #define UIC_VR 0x7 |
| #define UIC_VCR 0x8 |
| |
| struct uic *primary_uic; |
| |
| struct uic { |
| int index; |
| int dcrbase; |
| |
| raw_spinlock_t lock; |
| |
| /* The remapper for this UIC */ |
| struct irq_domain *irqhost; |
| }; |
| |
| static void uic_unmask_irq(struct irq_data *d) |
| { |
| struct uic *uic = irq_data_get_irq_chip_data(d); |
| unsigned int src = irqd_to_hwirq(d); |
| unsigned long flags; |
| u32 er, sr; |
| |
| sr = 1 << (31-src); |
| raw_spin_lock_irqsave(&uic->lock, flags); |
| /* ack level-triggered interrupts here */ |
| if (irqd_is_level_type(d)) |
| mtdcr(uic->dcrbase + UIC_SR, sr); |
| er = mfdcr(uic->dcrbase + UIC_ER); |
| er |= sr; |
| mtdcr(uic->dcrbase + UIC_ER, er); |
| raw_spin_unlock_irqrestore(&uic->lock, flags); |
| } |
| |
| static void uic_mask_irq(struct irq_data *d) |
| { |
| struct uic *uic = irq_data_get_irq_chip_data(d); |
| unsigned int src = irqd_to_hwirq(d); |
| unsigned long flags; |
| u32 er; |
| |
| raw_spin_lock_irqsave(&uic->lock, flags); |
| er = mfdcr(uic->dcrbase + UIC_ER); |
| er &= ~(1 << (31 - src)); |
| mtdcr(uic->dcrbase + UIC_ER, er); |
| raw_spin_unlock_irqrestore(&uic->lock, flags); |
| } |
| |
| static void uic_ack_irq(struct irq_data *d) |
| { |
| struct uic *uic = irq_data_get_irq_chip_data(d); |
| unsigned int src = irqd_to_hwirq(d); |
| unsigned long flags; |
| |
| raw_spin_lock_irqsave(&uic->lock, flags); |
| mtdcr(uic->dcrbase + UIC_SR, 1 << (31-src)); |
| raw_spin_unlock_irqrestore(&uic->lock, flags); |
| } |
| |
| static void uic_mask_ack_irq(struct irq_data *d) |
| { |
| struct uic *uic = irq_data_get_irq_chip_data(d); |
| unsigned int src = irqd_to_hwirq(d); |
| unsigned long flags; |
| u32 er, sr; |
| |
| sr = 1 << (31-src); |
| raw_spin_lock_irqsave(&uic->lock, flags); |
| er = mfdcr(uic->dcrbase + UIC_ER); |
| er &= ~sr; |
| mtdcr(uic->dcrbase + UIC_ER, er); |
| /* On the UIC, acking (i.e. clearing the SR bit) |
| * a level irq will have no effect if the interrupt |
| * is still asserted by the device, even if |
| * the interrupt is already masked. Therefore |
| * we only ack the egde interrupts here, while |
| * level interrupts are ack'ed after the actual |
| * isr call in the uic_unmask_irq() |
| */ |
| if (!irqd_is_level_type(d)) |
| mtdcr(uic->dcrbase + UIC_SR, sr); |
| raw_spin_unlock_irqrestore(&uic->lock, flags); |
| } |
| |
| static int uic_set_irq_type(struct irq_data *d, unsigned int flow_type) |
| { |
| struct uic *uic = irq_data_get_irq_chip_data(d); |
| unsigned int src = irqd_to_hwirq(d); |
| unsigned long flags; |
| int trigger, polarity; |
| u32 tr, pr, mask; |
| |
| switch (flow_type & IRQ_TYPE_SENSE_MASK) { |
| case IRQ_TYPE_NONE: |
| uic_mask_irq(d); |
| return 0; |
| |
| case IRQ_TYPE_EDGE_RISING: |
| trigger = 1; polarity = 1; |
| break; |
| case IRQ_TYPE_EDGE_FALLING: |
| trigger = 1; polarity = 0; |
| break; |
| case IRQ_TYPE_LEVEL_HIGH: |
| trigger = 0; polarity = 1; |
| break; |
| case IRQ_TYPE_LEVEL_LOW: |
| trigger = 0; polarity = 0; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| mask = ~(1 << (31 - src)); |
| |
| raw_spin_lock_irqsave(&uic->lock, flags); |
| tr = mfdcr(uic->dcrbase + UIC_TR); |
| pr = mfdcr(uic->dcrbase + UIC_PR); |
| tr = (tr & mask) | (trigger << (31-src)); |
| pr = (pr & mask) | (polarity << (31-src)); |
| |
| mtdcr(uic->dcrbase + UIC_PR, pr); |
| mtdcr(uic->dcrbase + UIC_TR, tr); |
| |
| raw_spin_unlock_irqrestore(&uic->lock, flags); |
| |
| return 0; |
| } |
| |
| static struct irq_chip uic_irq_chip = { |
| .name = "UIC", |
| .irq_unmask = uic_unmask_irq, |
| .irq_mask = uic_mask_irq, |
| .irq_mask_ack = uic_mask_ack_irq, |
| .irq_ack = uic_ack_irq, |
| .irq_set_type = uic_set_irq_type, |
| }; |
| |
| static int uic_host_map(struct irq_domain *h, unsigned int virq, |
| irq_hw_number_t hw) |
| { |
| struct uic *uic = h->host_data; |
| |
| irq_set_chip_data(virq, uic); |
| /* Despite the name, handle_level_irq() works for both level |
| * and edge irqs on UIC. FIXME: check this is correct */ |
| irq_set_chip_and_handler(virq, &uic_irq_chip, handle_level_irq); |
| |
| /* Set default irq type */ |
| irq_set_irq_type(virq, IRQ_TYPE_NONE); |
| |
| return 0; |
| } |
| |
| static const struct irq_domain_ops uic_host_ops = { |
| .map = uic_host_map, |
| .xlate = irq_domain_xlate_twocell, |
| }; |
| |
| void uic_irq_cascade(unsigned int virq, struct irq_desc *desc) |
| { |
| struct irq_chip *chip = irq_desc_get_chip(desc); |
| struct irq_data *idata = irq_desc_get_irq_data(desc); |
| struct uic *uic = irq_desc_get_handler_data(desc); |
| u32 msr; |
| int src; |
| int subvirq; |
| |
| raw_spin_lock(&desc->lock); |
| if (irqd_is_level_type(idata)) |
| chip->irq_mask(idata); |
| else |
| chip->irq_mask_ack(idata); |
| raw_spin_unlock(&desc->lock); |
| |
| msr = mfdcr(uic->dcrbase + UIC_MSR); |
| if (!msr) /* spurious interrupt */ |
| goto uic_irq_ret; |
| |
| src = 32 - ffs(msr); |
| |
| subvirq = irq_linear_revmap(uic->irqhost, src); |
| generic_handle_irq(subvirq); |
| |
| uic_irq_ret: |
| raw_spin_lock(&desc->lock); |
| if (irqd_is_level_type(idata)) |
| chip->irq_ack(idata); |
| if (!irqd_irq_disabled(idata) && chip->irq_unmask) |
| chip->irq_unmask(idata); |
| raw_spin_unlock(&desc->lock); |
| } |
| |
| static struct uic * __init uic_init_one(struct device_node *node) |
| { |
| struct uic *uic; |
| const u32 *indexp, *dcrreg; |
| int len; |
| |
| BUG_ON(! of_device_is_compatible(node, "ibm,uic")); |
| |
| uic = kzalloc(sizeof(*uic), GFP_KERNEL); |
| if (! uic) |
| return NULL; /* FIXME: panic? */ |
| |
| raw_spin_lock_init(&uic->lock); |
| indexp = of_get_property(node, "cell-index", &len); |
| if (!indexp || (len != sizeof(u32))) { |
| printk(KERN_ERR "uic: Device node %s has missing or invalid " |
| "cell-index property\n", node->full_name); |
| return NULL; |
| } |
| uic->index = *indexp; |
| |
| dcrreg = of_get_property(node, "dcr-reg", &len); |
| if (!dcrreg || (len != 2*sizeof(u32))) { |
| printk(KERN_ERR "uic: Device node %s has missing or invalid " |
| "dcr-reg property\n", node->full_name); |
| return NULL; |
| } |
| uic->dcrbase = *dcrreg; |
| |
| uic->irqhost = irq_domain_add_linear(node, NR_UIC_INTS, &uic_host_ops, |
| uic); |
| if (! uic->irqhost) |
| return NULL; /* FIXME: panic? */ |
| |
| /* Start with all interrupts disabled, level and non-critical */ |
| mtdcr(uic->dcrbase + UIC_ER, 0); |
| mtdcr(uic->dcrbase + UIC_CR, 0); |
| mtdcr(uic->dcrbase + UIC_TR, 0); |
| /* Clear any pending interrupts, in case the firmware left some */ |
| mtdcr(uic->dcrbase + UIC_SR, 0xffffffff); |
| |
| printk ("UIC%d (%d IRQ sources) at DCR 0x%x\n", uic->index, |
| NR_UIC_INTS, uic->dcrbase); |
| |
| return uic; |
| } |
| |
| void __init uic_init_tree(void) |
| { |
| struct device_node *np; |
| struct uic *uic; |
| const u32 *interrupts; |
| |
| /* First locate and initialize the top-level UIC */ |
| for_each_compatible_node(np, NULL, "ibm,uic") { |
| interrupts = of_get_property(np, "interrupts", NULL); |
| if (!interrupts) |
| break; |
| } |
| |
| BUG_ON(!np); /* uic_init_tree() assumes there's a UIC as the |
| * top-level interrupt controller */ |
| primary_uic = uic_init_one(np); |
| if (!primary_uic) |
| panic("Unable to initialize primary UIC %s\n", np->full_name); |
| |
| irq_set_default_host(primary_uic->irqhost); |
| of_node_put(np); |
| |
| /* The scan again for cascaded UICs */ |
| for_each_compatible_node(np, NULL, "ibm,uic") { |
| interrupts = of_get_property(np, "interrupts", NULL); |
| if (interrupts) { |
| /* Secondary UIC */ |
| int cascade_virq; |
| |
| uic = uic_init_one(np); |
| if (! uic) |
| panic("Unable to initialize a secondary UIC %s\n", |
| np->full_name); |
| |
| cascade_virq = irq_of_parse_and_map(np, 0); |
| |
| irq_set_handler_data(cascade_virq, uic); |
| irq_set_chained_handler(cascade_virq, uic_irq_cascade); |
| |
| /* FIXME: setup critical cascade?? */ |
| } |
| } |
| } |
| |
| /* Return an interrupt vector or NO_IRQ if no interrupt is pending. */ |
| unsigned int uic_get_irq(void) |
| { |
| u32 msr; |
| int src; |
| |
| BUG_ON(! primary_uic); |
| |
| msr = mfdcr(primary_uic->dcrbase + UIC_MSR); |
| src = 32 - ffs(msr); |
| |
| return irq_linear_revmap(primary_uic->irqhost, src); |
| } |