diff options
Diffstat (limited to 'drivers/irqchip/irq-vt8500.c')
| -rw-r--r-- | drivers/irqchip/irq-vt8500.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-vt8500.c b/drivers/irqchip/irq-vt8500.c new file mode 100644 index 0000000..d970595 --- /dev/null +++ b/drivers/irqchip/irq-vt8500.c @@ -0,0 +1,259 @@ +/* + * arch/arm/mach-vt8500/irq.c + * + * Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz> + * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* + * This file is copied and modified from the original irq.c provided by + * Alexey Charkov. Minor changes have been made for Device Tree Support. + */ + +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/interrupt.h> +#include <linux/bitops.h> + +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/of_address.h> + +#include <asm/irq.h> +#include <asm/exception.h> +#include <asm/mach/irq.h> + +#include "irqchip.h" + +#define VT8500_ICPC_IRQ 0x20 +#define VT8500_ICPC_FIQ 0x24 +#define VT8500_ICDC 0x40 /* Destination Control 64*u32 */ +#define VT8500_ICIS 0x80 /* Interrupt status, 16*u32 */ + +/* ICPC */ +#define ICPC_MASK 0x3F +#define ICPC_ROTATE BIT(6) + +/* IC_DCTR */ +#define ICDC_IRQ 0x00 +#define ICDC_FIQ 0x01 +#define ICDC_DSS0 0x02 +#define ICDC_DSS1 0x03 +#define ICDC_DSS2 0x04 +#define ICDC_DSS3 0x05 +#define ICDC_DSS4 0x06 +#define ICDC_DSS5 0x07 + +#define VT8500_INT_DISABLE 0 +#define VT8500_INT_ENABLE BIT(3) + +#define VT8500_TRIGGER_HIGH 0 +#define VT8500_TRIGGER_RISING BIT(5) +#define VT8500_TRIGGER_FALLING BIT(6) +#define VT8500_EDGE ( VT8500_TRIGGER_RISING \ + | VT8500_TRIGGER_FALLING) + +/* vt8500 has 1 intc, wm8505 and wm8650 have 2 */ +#define VT8500_INTC_MAX 2 + +struct vt8500_irq_data { + void __iomem *base; /* IO Memory base address */ + struct irq_domain *domain; /* Domain for this controller */ +}; + +/* Global variable for accessing io-mem addresses */ +static struct vt8500_irq_data intc[VT8500_INTC_MAX]; +static u32 active_cnt = 0; + +static void vt8500_irq_mask(struct irq_data *d) +{ + struct vt8500_irq_data *priv = d->domain->host_data; + void __iomem *base = priv->base; + void __iomem *stat_reg = base + VT8500_ICIS + (d->hwirq < 32 ? 0 : 4); + u8 edge, dctr; + u32 status; + + edge = readb(base + VT8500_ICDC + d->hwirq) & VT8500_EDGE; + if (edge) { + status = readl(stat_reg); + + status |= (1 << (d->hwirq & 0x1f)); + writel(status, stat_reg); + } else { + dctr = readb(base + VT8500_ICDC + d->hwirq); + dctr &= ~VT8500_INT_ENABLE; + writeb(dctr, base + VT8500_ICDC + d->hwirq); + } +} + +static void vt8500_irq_unmask(struct irq_data *d) +{ + struct vt8500_irq_data *priv = d->domain->host_data; + void __iomem *base = priv->base; + u8 dctr; + + dctr = readb(base + VT8500_ICDC + d->hwirq); + dctr |= VT8500_INT_ENABLE; + writeb(dctr, base + VT8500_ICDC + d->hwirq); +} + +static int vt8500_irq_set_type(struct irq_data *d, unsigned int flow_type) +{ + struct vt8500_irq_data *priv = d->domain->host_data; + void __iomem *base = priv->base; + u8 dctr; + + dctr = readb(base + VT8500_ICDC + d->hwirq); + dctr &= ~VT8500_EDGE; + + switch (flow_type) { + case IRQF_TRIGGER_LOW: + return -EINVAL; + case IRQF_TRIGGER_HIGH: + dctr |= VT8500_TRIGGER_HIGH; + __irq_set_handler_locked(d->irq, handle_level_irq); + break; + case IRQF_TRIGGER_FALLING: + dctr |= VT8500_TRIGGER_FALLING; + __irq_set_handler_locked(d->irq, handle_edge_irq); + break; + case IRQF_TRIGGER_RISING: + dctr |= VT8500_TRIGGER_RISING; + __irq_set_handler_locked(d->irq, handle_edge_irq); + break; + } + writeb(dctr, base + VT8500_ICDC + d->hwirq); + + return 0; +} + +static struct irq_chip vt8500_irq_chip = { + .name = "vt8500", + .irq_ack = vt8500_irq_mask, + .irq_mask = vt8500_irq_mask, + .irq_unmask = vt8500_irq_unmask, + .irq_set_type = vt8500_irq_set_type, +}; + +static void __init vt8500_init_irq_hw(void __iomem *base) +{ + u32 i; + + /* Enable rotating priority for IRQ */ + writel(ICPC_ROTATE, base + VT8500_ICPC_IRQ); + writel(0x00, base + VT8500_ICPC_FIQ); + + /* Disable all interrupts and route them to IRQ */ + for (i = 0; i < 64; i++) + writeb(VT8500_INT_DISABLE | ICDC_IRQ, base + VT8500_ICDC + i); +} + +static int vt8500_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + irq_set_chip_and_handler(virq, &vt8500_irq_chip, handle_level_irq); + set_irq_flags(virq, IRQF_VALID); + + return 0; +} + +static struct irq_domain_ops vt8500_irq_domain_ops = { + .map = vt8500_irq_map, + .xlate = irq_domain_xlate_onecell, +}; + +asmlinkage void __exception_irq_entry vt8500_handle_irq(struct pt_regs *regs) +{ + u32 stat, i; + int irqnr, virq; + void __iomem *base; + + /* Loop through each active controller */ + for (i=0; i<active_cnt; i++) { + base = intc[i].base; + irqnr = readl_relaxed(base) & 0x3F; + /* + Highest Priority register default = 63, so check that this + is a real interrupt by checking the status register + */ + if (irqnr == 63) { + stat = readl_relaxed(base + VT8500_ICIS + 4); + if (!(stat & BIT(31))) + continue; + } + + virq = irq_find_mapping(intc[i].domain, irqnr); + handle_IRQ(virq, regs); + } +} + +int __init vt8500_irq_init(struct device_node *node, struct device_node *parent) +{ + int irq, i; + struct device_node *np = node; + + if (active_cnt == VT8500_INTC_MAX) { + pr_err("%s: Interrupt controllers > VT8500_INTC_MAX\n", + __func__); + goto out; + } + + intc[active_cnt].base = of_iomap(np, 0); + intc[active_cnt].domain = irq_domain_add_linear(node, 64, + &vt8500_irq_domain_ops, &intc[active_cnt]); + + if (!intc[active_cnt].base) { + pr_err("%s: Unable to map IO memory\n", __func__); + goto out; + } + + if (!intc[active_cnt].domain) { + pr_err("%s: Unable to add irq domain!\n", __func__); + goto out; + } + + set_handle_irq(vt8500_handle_irq); + + vt8500_init_irq_hw(intc[active_cnt].base); + + pr_info("vt8500-irq: Added interrupt controller\n"); + + active_cnt++; + + /* check if this is a slaved controller */ + if (of_irq_count(np) != 0) { + /* check that we have the correct number of interrupts */ + if (of_irq_count(np) != 8) { + pr_err("%s: Incorrect IRQ map for slaved controller\n", + __func__); + return -EINVAL; + } + + for (i = 0; i < 8; i++) { + irq = irq_of_parse_and_map(np, i); + enable_irq(irq); + } + + pr_info("vt8500-irq: Enabled slave->parent interrupts\n"); + } +out: + return 0; +} + +IRQCHIP_DECLARE(vt8500_irq, "via,vt8500-intc", vt8500_irq_init); |