diff options
Diffstat (limited to 'drivers/irqchip/irq-orion.c')
| -rw-r--r-- | drivers/irqchip/irq-orion.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-orion.c b/drivers/irqchip/irq-orion.c new file mode 100644 index 000000000..c4b5ffb61 --- /dev/null +++ b/drivers/irqchip/irq-orion.c @@ -0,0 +1,206 @@ +/* + * Marvell Orion SoCs IRQ chip driver. + * + * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <asm/exception.h> +#include <asm/mach/irq.h> + +/* + * Orion SoC main interrupt controller + */ +#define ORION_IRQS_PER_CHIP 32 + +#define ORION_IRQ_CAUSE 0x00 +#define ORION_IRQ_MASK 0x04 +#define ORION_IRQ_FIQ_MASK 0x08 +#define ORION_IRQ_ENDP_MASK 0x0c + +static struct irq_domain *orion_irq_domain; + +static void +__exception_irq_entry orion_handle_irq(struct pt_regs *regs) +{ + struct irq_domain_chip_generic *dgc = orion_irq_domain->gc; + int n, base = 0; + + for (n = 0; n < dgc->num_chips; n++, base += ORION_IRQS_PER_CHIP) { + struct irq_chip_generic *gc = + irq_get_domain_generic_chip(orion_irq_domain, base); + u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) & + gc->mask_cache; + while (stat) { + u32 hwirq = __fls(stat); + handle_domain_irq(orion_irq_domain, + gc->irq_base + hwirq, regs); + stat &= ~(1 << hwirq); + } + } +} + +static int __init orion_irq_init(struct device_node *np, + struct device_node *parent) +{ + unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; + int n, ret, base, num_chips = 0; + struct resource r; + + /* count number of irq chips by valid reg addresses */ + while (of_address_to_resource(np, num_chips, &r) == 0) + num_chips++; + + orion_irq_domain = irq_domain_add_linear(np, + num_chips * ORION_IRQS_PER_CHIP, + &irq_generic_chip_ops, NULL); + if (!orion_irq_domain) + panic("%pOFn: unable to add irq domain\n", np); + + ret = irq_alloc_domain_generic_chips(orion_irq_domain, + ORION_IRQS_PER_CHIP, 1, np->full_name, + handle_level_irq, clr, 0, + IRQ_GC_INIT_MASK_CACHE); + if (ret) + panic("%pOFn: unable to alloc irq domain gc\n", np); + + for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) { + struct irq_chip_generic *gc = + irq_get_domain_generic_chip(orion_irq_domain, base); + + of_address_to_resource(np, n, &r); + + if (!request_mem_region(r.start, resource_size(&r), np->name)) + panic("%pOFn: unable to request mem region %d", + np, n); + + gc->reg_base = ioremap(r.start, resource_size(&r)); + if (!gc->reg_base) + panic("%pOFn: unable to map resource %d", np, n); + + gc->chip_types[0].regs.mask = ORION_IRQ_MASK; + gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; + gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; + + /* mask all interrupts */ + writel(0, gc->reg_base + ORION_IRQ_MASK); + } + + set_handle_irq(orion_handle_irq); + return 0; +} +IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init); + +/* + * Orion SoC bridge interrupt controller + */ +#define ORION_BRIDGE_IRQ_CAUSE 0x00 +#define ORION_BRIDGE_IRQ_MASK 0x04 + +static void orion_bridge_irq_handler(struct irq_desc *desc) +{ + struct irq_domain *d = irq_desc_get_handler_data(desc); + + struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0); + u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) & + gc->mask_cache; + + while (stat) { + u32 hwirq = __fls(stat); + + generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq)); + stat &= ~(1 << hwirq); + } +} + +/* + * Bridge IRQ_CAUSE is asserted regardless of IRQ_MASK register. + * To avoid interrupt events on stale irqs, we clear them before unmask. + */ +static unsigned int orion_bridge_irq_startup(struct irq_data *d) +{ + struct irq_chip_type *ct = irq_data_get_chip_type(d); + + ct->chip.irq_ack(d); + ct->chip.irq_unmask(d); + return 0; +} + +static int __init orion_bridge_irq_init(struct device_node *np, + struct device_node *parent) +{ + unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; + struct resource r; + struct irq_domain *domain; + struct irq_chip_generic *gc; + int ret, irq, nrirqs = 32; + + /* get optional number of interrupts provided */ + of_property_read_u32(np, "marvell,#interrupts", &nrirqs); + + domain = irq_domain_add_linear(np, nrirqs, + &irq_generic_chip_ops, NULL); + if (!domain) { + pr_err("%pOFn: unable to add irq domain\n", np); + return -ENOMEM; + } + + ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name, + handle_edge_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE); + if (ret) { + pr_err("%pOFn: unable to alloc irq domain gc\n", np); + return ret; + } + + ret = of_address_to_resource(np, 0, &r); + if (ret) { + pr_err("%pOFn: unable to get resource\n", np); + return ret; + } + + if (!request_mem_region(r.start, resource_size(&r), np->name)) { + pr_err("%s: unable to request mem region\n", np->name); + return -ENOMEM; + } + + /* Map the parent interrupt for the chained handler */ + irq = irq_of_parse_and_map(np, 0); + if (irq <= 0) { + pr_err("%pOFn: unable to parse irq\n", np); + return -EINVAL; + } + + gc = irq_get_domain_generic_chip(domain, 0); + gc->reg_base = ioremap(r.start, resource_size(&r)); + if (!gc->reg_base) { + pr_err("%pOFn: unable to map resource\n", np); + return -ENOMEM; + } + + gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE; + gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK; + gc->chip_types[0].chip.irq_startup = orion_bridge_irq_startup; + gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit; + gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; + gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; + + /* mask and clear all interrupts */ + writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK); + writel(0, gc->reg_base + ORION_BRIDGE_IRQ_CAUSE); + + irq_set_chained_handler_and_data(irq, orion_bridge_irq_handler, + domain); + + return 0; +} +IRQCHIP_DECLARE(orion_bridge_intc, + "marvell,orion-bridge-intc", orion_bridge_irq_init); |