diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/irqchip/Makefile | 1 | ||||
| -rw-r--r-- | drivers/irqchip/irq-dove.c | 126 |
2 files changed, 127 insertions, 0 deletions
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index 5194afb39e78..98589e7a1f62 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -1,6 +1,7 @@ obj-$(CONFIG_IRQCHIP) += irqchip.o obj-$(CONFIG_ARCH_BCM2835) += irq-bcm2835.o +obj-$(CONFIG_ARCH_DOVE) += irq-dove.o obj-$(CONFIG_ARCH_EXYNOS) += exynos-combiner.o obj-$(CONFIG_ARCH_MMP) += irq-mmp.o obj-$(CONFIG_ARCH_MVEBU) += irq-armada-370-xp.o diff --git a/drivers/irqchip/irq-dove.c b/drivers/irqchip/irq-dove.c new file mode 100644 index 000000000000..788acd89848a --- /dev/null +++ b/drivers/irqchip/irq-dove.c @@ -0,0 +1,126 @@ +/* + * Marvell Dove SoCs PMU IRQ chip driver. + * + * Andrew Lunn <andrew@lunn.ch> + * + * 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/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <asm/exception.h> +#include <asm/mach/irq.h> + +#include "irqchip.h" + +#define DOVE_PMU_IRQ_CAUSE 0x00 +#define DOVE_PMU_IRQ_MASK 0x04 + +static void dove_pmu_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + struct irq_domain *d = irq_get_handler_data(irq); + struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0); + u32 stat = readl_relaxed(gc->reg_base + DOVE_PMU_IRQ_CAUSE) & + gc->mask_cache; + + while (stat) { + u32 hwirq = ffs(stat) - 1; + + generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq)); + stat &= ~(1 << hwirq); + } +} + +static void pmu_irq_ack(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct irq_chip_type *ct = irq_data_get_chip_type(d); + u32 mask = ~d->mask; + + /* + * The PMU mask register is not RW0C: it is RW. This means that + * the bits take whatever value is written to them; if you write + * a '1', you will set the interrupt. + * + * Unfortunately this means there is NO race free way to clear + * these interrupts. + * + * So, let's structure the code so that the window is as small as + * possible. + */ + irq_gc_lock(gc); + mask &= irq_reg_readl(gc->reg_base + ct->regs.ack); + irq_reg_writel(mask, gc->reg_base + ct->regs.ack); + irq_gc_unlock(gc); +} + +static int __init dove_pmu_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 = 7; + + domain = irq_domain_add_linear(np, nrirqs, + &irq_generic_chip_ops, NULL); + if (!domain) { + pr_err("%s: unable to add irq domain\n", np->name); + return -ENOMEM; + } + + ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name, + handle_level_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE); + if (ret) { + pr_err("%s: unable to alloc irq domain gc\n", np->name); + return ret; + } + + ret = of_address_to_resource(np, 0, &r); + if (ret) { + pr_err("%s: unable to get resource\n", np->name); + 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("%s: unable to parse irq\n", np->name); + 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("%s: unable to map resource\n", np->name); + return -ENOMEM; + } + + gc->chip_types[0].regs.ack = DOVE_PMU_IRQ_CAUSE; + gc->chip_types[0].regs.mask = DOVE_PMU_IRQ_MASK; + gc->chip_types[0].chip.irq_ack = pmu_irq_ack; + 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 + DOVE_PMU_IRQ_MASK); + writel(0, gc->reg_base + DOVE_PMU_IRQ_CAUSE); + + irq_set_handler_data(irq, domain); + irq_set_chained_handler(irq, dove_pmu_irq_handler); + + return 0; +} +IRQCHIP_DECLARE(dove_pmu_intc, + "marvell,dove-pmu-intc", dove_pmu_irq_init); |