diff options
Diffstat (limited to 'drivers/irqchip/irq-moxart.c')
-rw-r--r-- | drivers/irqchip/irq-moxart.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-moxart.c b/drivers/irqchip/irq-moxart.c new file mode 100644 index 000000000..00b3cc908 --- /dev/null +++ b/drivers/irqchip/irq-moxart.c @@ -0,0 +1,117 @@ +/* + * MOXA ART SoCs IRQ chip driver. + * + * Copyright (C) 2013 Jonas Jensen + * + * Jonas Jensen <jonas.jensen@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/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/irqdomain.h> + +#include <asm/exception.h> + +#include "irqchip.h" + +#define IRQ_SOURCE_REG 0 +#define IRQ_MASK_REG 0x04 +#define IRQ_CLEAR_REG 0x08 +#define IRQ_MODE_REG 0x0c +#define IRQ_LEVEL_REG 0x10 +#define IRQ_STATUS_REG 0x14 + +#define FIQ_SOURCE_REG 0x20 +#define FIQ_MASK_REG 0x24 +#define FIQ_CLEAR_REG 0x28 +#define FIQ_MODE_REG 0x2c +#define FIQ_LEVEL_REG 0x30 +#define FIQ_STATUS_REG 0x34 + + +struct moxart_irq_data { + void __iomem *base; + struct irq_domain *domain; + unsigned int interrupt_mask; +}; + +static struct moxart_irq_data intc; + +static void __exception_irq_entry handle_irq(struct pt_regs *regs) +{ + u32 irqstat; + int hwirq; + + irqstat = readl(intc.base + IRQ_STATUS_REG); + + while (irqstat) { + hwirq = ffs(irqstat) - 1; + handle_IRQ(irq_linear_revmap(intc.domain, hwirq), regs); + irqstat &= ~(1 << hwirq); + } +} + +static int __init moxart_of_intc_init(struct device_node *node, + struct device_node *parent) +{ + unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN; + int ret; + struct irq_chip_generic *gc; + + intc.base = of_iomap(node, 0); + if (!intc.base) { + pr_err("%s: unable to map IC registers\n", + node->full_name); + return -EINVAL; + } + + intc.domain = irq_domain_add_linear(node, 32, &irq_generic_chip_ops, + intc.base); + if (!intc.domain) { + pr_err("%s: unable to create IRQ domain\n", node->full_name); + return -EINVAL; + } + + ret = irq_alloc_domain_generic_chips(intc.domain, 32, 1, + "MOXARTINTC", handle_edge_irq, + clr, 0, IRQ_GC_INIT_MASK_CACHE); + if (ret) { + pr_err("%s: could not allocate generic chip\n", + node->full_name); + irq_domain_remove(intc.domain); + return -EINVAL; + } + + ret = of_property_read_u32(node, "interrupt-mask", + &intc.interrupt_mask); + if (ret) + pr_err("%s: could not read interrupt-mask DT property\n", + node->full_name); + + gc = irq_get_domain_generic_chip(intc.domain, 0); + + gc->reg_base = intc.base; + gc->chip_types[0].regs.mask = IRQ_MASK_REG; + gc->chip_types[0].regs.ack = IRQ_CLEAR_REG; + gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_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; + + writel(0, intc.base + IRQ_MASK_REG); + writel(0xffffffff, intc.base + IRQ_CLEAR_REG); + + writel(intc.interrupt_mask, intc.base + IRQ_MODE_REG); + writel(intc.interrupt_mask, intc.base + IRQ_LEVEL_REG); + + set_handle_irq(handle_irq); + + return 0; +} +IRQCHIP_DECLARE(moxa_moxart_ic, "moxa,moxart-ic", moxart_of_intc_init); |