diff options
Diffstat (limited to 'arch/powerpc/platforms/82xx/pq2ads-pci-pic.c')
| -rw-r--r-- | arch/powerpc/platforms/82xx/pq2ads-pci-pic.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c b/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c new file mode 100644 index 00000000000..a8013816125 --- /dev/null +++ b/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c @@ -0,0 +1,195 @@ +/* + * PQ2 ADS-style PCI interrupt controller + * + * Copyright 2007 Freescale Semiconductor, Inc. + * Author: Scott Wood <scottwood@freescale.com> + * + * Loosely based on mpc82xx ADS support by Vitaly Bordug <vbordug@ru.mvista.com> + * Copyright (c) 2006 MontaVista Software, Inc. + * + * 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. + */ + +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/irq.h> +#include <linux/types.h> +#include <linux/bootmem.h> + +#include <asm/io.h> +#include <asm/prom.h> +#include <asm/cpm2.h> + +#include "pq2.h" + +static DEFINE_SPINLOCK(pci_pic_lock); + +struct pq2ads_pci_pic { + struct device_node *node; + struct irq_host *host; + + struct { + u32 stat; + u32 mask; + } __iomem *regs; +}; + +#define NUM_IRQS 32 + +static void pq2ads_pci_mask_irq(unsigned int virq) +{ + struct pq2ads_pci_pic *priv = get_irq_chip_data(virq); + int irq = NUM_IRQS - virq_to_hw(virq) - 1; + + if (irq != -1) { + unsigned long flags; + spin_lock_irqsave(&pci_pic_lock, flags); + + setbits32(&priv->regs->mask, 1 << irq); + mb(); + + spin_unlock_irqrestore(&pci_pic_lock, flags); + } +} + +static void pq2ads_pci_unmask_irq(unsigned int virq) +{ + struct pq2ads_pci_pic *priv = get_irq_chip_data(virq); + int irq = NUM_IRQS - virq_to_hw(virq) - 1; + + if (irq != -1) { + unsigned long flags; + + spin_lock_irqsave(&pci_pic_lock, flags); + clrbits32(&priv->regs->mask, 1 << irq); + spin_unlock_irqrestore(&pci_pic_lock, flags); + } +} + +static struct irq_chip pq2ads_pci_ic = { + .typename = "PQ2 ADS PCI", + .name = "PQ2 ADS PCI", + .end = pq2ads_pci_unmask_irq, + .mask = pq2ads_pci_mask_irq, + .mask_ack = pq2ads_pci_mask_irq, + .ack = pq2ads_pci_mask_irq, + .unmask = pq2ads_pci_unmask_irq, + .enable = pq2ads_pci_unmask_irq, + .disable = pq2ads_pci_mask_irq +}; + +static void pq2ads_pci_irq_demux(unsigned int irq, struct irq_desc *desc) +{ + struct pq2ads_pci_pic *priv = desc->handler_data; + u32 stat, mask, pend; + int bit; + + for (;;) { + stat = in_be32(&priv->regs->stat); + mask = in_be32(&priv->regs->mask); + + pend = stat & ~mask; + + if (!pend) + break; + + for (bit = 0; pend != 0; ++bit, pend <<= 1) { + if (pend & 0x80000000) { + int virq = irq_linear_revmap(priv->host, bit); + generic_handle_irq(virq); + } + } + } +} + +static int pci_pic_host_map(struct irq_host *h, unsigned int virq, + irq_hw_number_t hw) +{ + get_irq_desc(virq)->status |= IRQ_LEVEL; + set_irq_chip_data(virq, h->host_data); + set_irq_chip(virq, &pq2ads_pci_ic); + return 0; +} + +static void pci_host_unmap(struct irq_host *h, unsigned int virq) +{ + /* remove chip and handler */ + set_irq_chip_data(virq, NULL); + set_irq_chip(virq, NULL); +} + +static struct irq_host_ops pci_pic_host_ops = { + .map = pci_pic_host_map, + .unmap = pci_host_unmap, +}; + +int __init pq2ads_pci_init_irq(void) +{ + struct pq2ads_pci_pic *priv; + struct irq_host *host; + struct device_node *np; + int ret = -ENODEV; + int irq; + + np = of_find_compatible_node(NULL, NULL, "fsl,pq2ads-pci-pic"); + if (!np) { + printk(KERN_ERR "No pci pic node in device tree.\n"); + of_node_put(np); + goto out; + } + + irq = irq_of_parse_and_map(np, 0); + if (irq == NO_IRQ) { + printk(KERN_ERR "No interrupt in pci pic node.\n"); + of_node_put(np); + goto out; + } + + priv = alloc_bootmem(sizeof(struct pq2ads_pci_pic)); + if (!priv) { + of_node_put(np); + ret = -ENOMEM; + goto out_unmap_irq; + } + + /* PCI interrupt controller registers: status and mask */ + priv->regs = of_iomap(np, 0); + if (!priv->regs) { + printk(KERN_ERR "Cannot map PCI PIC registers.\n"); + goto out_free_bootmem; + } + + /* mask all PCI interrupts */ + out_be32(&priv->regs->mask, ~0); + mb(); + + host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, NUM_IRQS, + &pci_pic_host_ops, NUM_IRQS); + if (!host) { + ret = -ENOMEM; + goto out_unmap_regs; + } + + host->host_data = priv; + + priv->host = host; + host->host_data = priv; + set_irq_data(irq, priv); + set_irq_chained_handler(irq, pq2ads_pci_irq_demux); + + of_node_put(np); + return 0; + +out_unmap_regs: + iounmap(priv->regs); +out_free_bootmem: + free_bootmem((unsigned long)priv, + sizeof(sizeof(struct pq2ads_pci_pic))); + of_node_put(np); +out_unmap_irq: + irq_dispose_mapping(irq); +out: + return ret; +} |