diff options
Diffstat (limited to 'drivers/irqchip/irq-ls1x.c')
| -rw-r--r-- | drivers/irqchip/irq-ls1x.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-ls1x.c b/drivers/irqchip/irq-ls1x.c new file mode 100644 index 000000000..353111a10 --- /dev/null +++ b/drivers/irqchip/irq-ls1x.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019, Jiaxun Yang <jiaxun.yang@flygoat.com> + * Loongson-1 platform IRQ support + */ + +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/irqchip.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/io.h> +#include <linux/irqchip/chained_irq.h> + +#define LS_REG_INTC_STATUS 0x00 +#define LS_REG_INTC_EN 0x04 +#define LS_REG_INTC_SET 0x08 +#define LS_REG_INTC_CLR 0x0c +#define LS_REG_INTC_POL 0x10 +#define LS_REG_INTC_EDGE 0x14 + +/** + * struct ls1x_intc_priv - private ls1x-intc data. + * @domain: IRQ domain. + * @intc_base: IO Base of intc registers. + */ + +struct ls1x_intc_priv { + struct irq_domain *domain; + void __iomem *intc_base; +}; + + +static void ls1x_chained_handle_irq(struct irq_desc *desc) +{ + struct ls1x_intc_priv *priv = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + u32 pending; + + chained_irq_enter(chip, desc); + pending = readl(priv->intc_base + LS_REG_INTC_STATUS) & + readl(priv->intc_base + LS_REG_INTC_EN); + + if (!pending) + spurious_interrupt(); + + while (pending) { + int bit = __ffs(pending); + + generic_handle_irq(irq_find_mapping(priv->domain, bit)); + pending &= ~BIT(bit); + } + + chained_irq_exit(chip, desc); +} + +static void ls_intc_set_bit(struct irq_chip_generic *gc, + unsigned int offset, + u32 mask, bool set) +{ + if (set) + writel(readl(gc->reg_base + offset) | mask, + gc->reg_base + offset); + else + writel(readl(gc->reg_base + offset) & ~mask, + gc->reg_base + offset); +} + +static int ls_intc_set_type(struct irq_data *data, unsigned int type) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); + u32 mask = data->mask; + + switch (type) { + case IRQ_TYPE_LEVEL_HIGH: + ls_intc_set_bit(gc, LS_REG_INTC_EDGE, mask, false); + ls_intc_set_bit(gc, LS_REG_INTC_POL, mask, true); + break; + case IRQ_TYPE_LEVEL_LOW: + ls_intc_set_bit(gc, LS_REG_INTC_EDGE, mask, false); + ls_intc_set_bit(gc, LS_REG_INTC_POL, mask, false); + break; + case IRQ_TYPE_EDGE_RISING: + ls_intc_set_bit(gc, LS_REG_INTC_EDGE, mask, true); + ls_intc_set_bit(gc, LS_REG_INTC_POL, mask, true); + break; + case IRQ_TYPE_EDGE_FALLING: + ls_intc_set_bit(gc, LS_REG_INTC_EDGE, mask, true); + ls_intc_set_bit(gc, LS_REG_INTC_POL, mask, false); + break; + default: + return -EINVAL; + } + + irqd_set_trigger_type(data, type); + return irq_setup_alt_chip(data, type); +} + + +static int __init ls1x_intc_of_init(struct device_node *node, + struct device_node *parent) +{ + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + struct ls1x_intc_priv *priv; + int parent_irq, err = 0; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->intc_base = of_iomap(node, 0); + if (!priv->intc_base) { + err = -ENODEV; + goto out_free_priv; + } + + parent_irq = irq_of_parse_and_map(node, 0); + if (!parent_irq) { + pr_err("ls1x-irq: unable to get parent irq\n"); + err = -ENODEV; + goto out_iounmap; + } + + /* Set up an IRQ domain */ + priv->domain = irq_domain_add_linear(node, 32, &irq_generic_chip_ops, + NULL); + if (!priv->domain) { + pr_err("ls1x-irq: cannot add IRQ domain\n"); + err = -ENOMEM; + goto out_iounmap; + } + + err = irq_alloc_domain_generic_chips(priv->domain, 32, 2, + node->full_name, handle_level_irq, + IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN, 0, + IRQ_GC_INIT_MASK_CACHE); + if (err) { + pr_err("ls1x-irq: unable to register IRQ domain\n"); + goto out_free_domain; + } + + /* Mask all irqs */ + writel(0x0, priv->intc_base + LS_REG_INTC_EN); + + /* Ack all irqs */ + writel(0xffffffff, priv->intc_base + LS_REG_INTC_CLR); + + /* Set all irqs to high level triggered */ + writel(0xffffffff, priv->intc_base + LS_REG_INTC_POL); + + gc = irq_get_domain_generic_chip(priv->domain, 0); + + gc->reg_base = priv->intc_base; + + ct = gc->chip_types; + ct[0].type = IRQ_TYPE_LEVEL_MASK; + ct[0].regs.mask = LS_REG_INTC_EN; + ct[0].regs.ack = LS_REG_INTC_CLR; + ct[0].chip.irq_unmask = irq_gc_mask_set_bit; + ct[0].chip.irq_mask = irq_gc_mask_clr_bit; + ct[0].chip.irq_ack = irq_gc_ack_set_bit; + ct[0].chip.irq_set_type = ls_intc_set_type; + ct[0].handler = handle_level_irq; + + ct[1].type = IRQ_TYPE_EDGE_BOTH; + ct[1].regs.mask = LS_REG_INTC_EN; + ct[1].regs.ack = LS_REG_INTC_CLR; + ct[1].chip.irq_unmask = irq_gc_mask_set_bit; + ct[1].chip.irq_mask = irq_gc_mask_clr_bit; + ct[1].chip.irq_ack = irq_gc_ack_set_bit; + ct[1].chip.irq_set_type = ls_intc_set_type; + ct[1].handler = handle_edge_irq; + + irq_set_chained_handler_and_data(parent_irq, + ls1x_chained_handle_irq, priv); + + return 0; + +out_free_domain: + irq_domain_remove(priv->domain); +out_iounmap: + iounmap(priv->intc_base); +out_free_priv: + kfree(priv); + + return err; +} + +IRQCHIP_DECLARE(ls1x_intc, "loongson,ls1x-intc", ls1x_intc_of_init); |