diff options
Diffstat (limited to 'kernel/drivers/irqchip/irq-renesas-intc-irqpin.c')
| -rw-r--r-- | kernel/drivers/irqchip/irq-renesas-intc-irqpin.c | 614 |
1 files changed, 614 insertions, 0 deletions
diff --git a/kernel/drivers/irqchip/irq-renesas-intc-irqpin.c b/kernel/drivers/irqchip/irq-renesas-intc-irqpin.c new file mode 100644 index 000000000..9a0767b9c --- /dev/null +++ b/kernel/drivers/irqchip/irq-renesas-intc-irqpin.c @@ -0,0 +1,614 @@ +/* + * Renesas INTC External IRQ Pin Driver + * + * Copyright (C) 2013 Magnus Damm + * + * 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 + * + * 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 + */ + +#include <linux/clk.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_data/irq-renesas-intc-irqpin.h> +#include <linux/pm_runtime.h> + +#define INTC_IRQPIN_MAX 8 /* maximum 8 interrupts per driver instance */ + +#define INTC_IRQPIN_REG_SENSE 0 /* ICRn */ +#define INTC_IRQPIN_REG_PRIO 1 /* INTPRInn */ +#define INTC_IRQPIN_REG_SOURCE 2 /* INTREQnn */ +#define INTC_IRQPIN_REG_MASK 3 /* INTMSKnn */ +#define INTC_IRQPIN_REG_CLEAR 4 /* INTMSKCLRnn */ +#define INTC_IRQPIN_REG_NR_MANDATORY 5 +#define INTC_IRQPIN_REG_IRLM 5 /* ICR0 with IRLM bit (optional) */ +#define INTC_IRQPIN_REG_NR 6 + +/* INTC external IRQ PIN hardware register access: + * + * SENSE is read-write 32-bit with 2-bits or 4-bits per IRQ (*) + * PRIO is read-write 32-bit with 4-bits per IRQ (**) + * SOURCE is read-only 32-bit or 8-bit with 1-bit per IRQ (***) + * MASK is write-only 32-bit or 8-bit with 1-bit per IRQ (***) + * CLEAR is write-only 32-bit or 8-bit with 1-bit per IRQ (***) + * + * (*) May be accessed by more than one driver instance - lock needed + * (**) Read-modify-write access by one driver instance - lock needed + * (***) Accessed by one driver instance only - no locking needed + */ + +struct intc_irqpin_iomem { + void __iomem *iomem; + unsigned long (*read)(void __iomem *iomem); + void (*write)(void __iomem *iomem, unsigned long data); + int width; +}; + +struct intc_irqpin_irq { + int hw_irq; + int requested_irq; + int domain_irq; + struct intc_irqpin_priv *p; +}; + +struct intc_irqpin_priv { + struct intc_irqpin_iomem iomem[INTC_IRQPIN_REG_NR]; + struct intc_irqpin_irq irq[INTC_IRQPIN_MAX]; + struct renesas_intc_irqpin_config config; + unsigned int number_of_irqs; + struct platform_device *pdev; + struct irq_chip irq_chip; + struct irq_domain *irq_domain; + struct clk *clk; + bool shared_irqs; + u8 shared_irq_mask; +}; + +struct intc_irqpin_irlm_config { + unsigned int irlm_bit; +}; + +static unsigned long intc_irqpin_read32(void __iomem *iomem) +{ + return ioread32(iomem); +} + +static unsigned long intc_irqpin_read8(void __iomem *iomem) +{ + return ioread8(iomem); +} + +static void intc_irqpin_write32(void __iomem *iomem, unsigned long data) +{ + iowrite32(data, iomem); +} + +static void intc_irqpin_write8(void __iomem *iomem, unsigned long data) +{ + iowrite8(data, iomem); +} + +static inline unsigned long intc_irqpin_read(struct intc_irqpin_priv *p, + int reg) +{ + struct intc_irqpin_iomem *i = &p->iomem[reg]; + + return i->read(i->iomem); +} + +static inline void intc_irqpin_write(struct intc_irqpin_priv *p, + int reg, unsigned long data) +{ + struct intc_irqpin_iomem *i = &p->iomem[reg]; + + i->write(i->iomem, data); +} + +static inline unsigned long intc_irqpin_hwirq_mask(struct intc_irqpin_priv *p, + int reg, int hw_irq) +{ + return BIT((p->iomem[reg].width - 1) - hw_irq); +} + +static inline void intc_irqpin_irq_write_hwirq(struct intc_irqpin_priv *p, + int reg, int hw_irq) +{ + intc_irqpin_write(p, reg, intc_irqpin_hwirq_mask(p, reg, hw_irq)); +} + +static DEFINE_RAW_SPINLOCK(intc_irqpin_lock); /* only used by slow path */ + +static void intc_irqpin_read_modify_write(struct intc_irqpin_priv *p, + int reg, int shift, + int width, int value) +{ + unsigned long flags; + unsigned long tmp; + + raw_spin_lock_irqsave(&intc_irqpin_lock, flags); + + tmp = intc_irqpin_read(p, reg); + tmp &= ~(((1 << width) - 1) << shift); + tmp |= value << shift; + intc_irqpin_write(p, reg, tmp); + + raw_spin_unlock_irqrestore(&intc_irqpin_lock, flags); +} + +static void intc_irqpin_mask_unmask_prio(struct intc_irqpin_priv *p, + int irq, int do_mask) +{ + /* The PRIO register is assumed to be 32-bit with fixed 4-bit fields. */ + int bitfield_width = 4; + int shift = 32 - (irq + 1) * bitfield_width; + + intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_PRIO, + shift, bitfield_width, + do_mask ? 0 : (1 << bitfield_width) - 1); +} + +static int intc_irqpin_set_sense(struct intc_irqpin_priv *p, int irq, int value) +{ + /* The SENSE register is assumed to be 32-bit. */ + int bitfield_width = p->config.sense_bitfield_width; + int shift = 32 - (irq + 1) * bitfield_width; + + dev_dbg(&p->pdev->dev, "sense irq = %d, mode = %d\n", irq, value); + + if (value >= (1 << bitfield_width)) + return -EINVAL; + + intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_SENSE, shift, + bitfield_width, value); + return 0; +} + +static void intc_irqpin_dbg(struct intc_irqpin_irq *i, char *str) +{ + dev_dbg(&i->p->pdev->dev, "%s (%d:%d:%d)\n", + str, i->requested_irq, i->hw_irq, i->domain_irq); +} + +static void intc_irqpin_irq_enable(struct irq_data *d) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + int hw_irq = irqd_to_hwirq(d); + + intc_irqpin_dbg(&p->irq[hw_irq], "enable"); + intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); +} + +static void intc_irqpin_irq_disable(struct irq_data *d) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + int hw_irq = irqd_to_hwirq(d); + + intc_irqpin_dbg(&p->irq[hw_irq], "disable"); + intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); +} + +static void intc_irqpin_shared_irq_enable(struct irq_data *d) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + int hw_irq = irqd_to_hwirq(d); + + intc_irqpin_dbg(&p->irq[hw_irq], "shared enable"); + intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_CLEAR, hw_irq); + + p->shared_irq_mask &= ~BIT(hw_irq); +} + +static void intc_irqpin_shared_irq_disable(struct irq_data *d) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + int hw_irq = irqd_to_hwirq(d); + + intc_irqpin_dbg(&p->irq[hw_irq], "shared disable"); + intc_irqpin_irq_write_hwirq(p, INTC_IRQPIN_REG_MASK, hw_irq); + + p->shared_irq_mask |= BIT(hw_irq); +} + +static void intc_irqpin_irq_enable_force(struct irq_data *d) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + int irq = p->irq[irqd_to_hwirq(d)].requested_irq; + + intc_irqpin_irq_enable(d); + + /* enable interrupt through parent interrupt controller, + * assumes non-shared interrupt with 1:1 mapping + * needed for busted IRQs on some SoCs like sh73a0 + */ + irq_get_chip(irq)->irq_unmask(irq_get_irq_data(irq)); +} + +static void intc_irqpin_irq_disable_force(struct irq_data *d) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + int irq = p->irq[irqd_to_hwirq(d)].requested_irq; + + /* disable interrupt through parent interrupt controller, + * assumes non-shared interrupt with 1:1 mapping + * needed for busted IRQs on some SoCs like sh73a0 + */ + irq_get_chip(irq)->irq_mask(irq_get_irq_data(irq)); + intc_irqpin_irq_disable(d); +} + +#define INTC_IRQ_SENSE_VALID 0x10 +#define INTC_IRQ_SENSE(x) (x + INTC_IRQ_SENSE_VALID) + +static unsigned char intc_irqpin_sense[IRQ_TYPE_SENSE_MASK + 1] = { + [IRQ_TYPE_EDGE_FALLING] = INTC_IRQ_SENSE(0x00), + [IRQ_TYPE_EDGE_RISING] = INTC_IRQ_SENSE(0x01), + [IRQ_TYPE_LEVEL_LOW] = INTC_IRQ_SENSE(0x02), + [IRQ_TYPE_LEVEL_HIGH] = INTC_IRQ_SENSE(0x03), + [IRQ_TYPE_EDGE_BOTH] = INTC_IRQ_SENSE(0x04), +}; + +static int intc_irqpin_irq_set_type(struct irq_data *d, unsigned int type) +{ + unsigned char value = intc_irqpin_sense[type & IRQ_TYPE_SENSE_MASK]; + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + + if (!(value & INTC_IRQ_SENSE_VALID)) + return -EINVAL; + + return intc_irqpin_set_sense(p, irqd_to_hwirq(d), + value ^ INTC_IRQ_SENSE_VALID); +} + +static int intc_irqpin_irq_set_wake(struct irq_data *d, unsigned int on) +{ + struct intc_irqpin_priv *p = irq_data_get_irq_chip_data(d); + + if (!p->clk) + return 0; + + if (on) + clk_enable(p->clk); + else + clk_disable(p->clk); + + return 0; +} + +static irqreturn_t intc_irqpin_irq_handler(int irq, void *dev_id) +{ + struct intc_irqpin_irq *i = dev_id; + struct intc_irqpin_priv *p = i->p; + unsigned long bit; + + intc_irqpin_dbg(i, "demux1"); + bit = intc_irqpin_hwirq_mask(p, INTC_IRQPIN_REG_SOURCE, i->hw_irq); + + if (intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE) & bit) { + intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, ~bit); + intc_irqpin_dbg(i, "demux2"); + generic_handle_irq(i->domain_irq); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +static irqreturn_t intc_irqpin_shared_irq_handler(int irq, void *dev_id) +{ + struct intc_irqpin_priv *p = dev_id; + unsigned int reg_source = intc_irqpin_read(p, INTC_IRQPIN_REG_SOURCE); + irqreturn_t status = IRQ_NONE; + int k; + + for (k = 0; k < 8; k++) { + if (reg_source & BIT(7 - k)) { + if (BIT(k) & p->shared_irq_mask) + continue; + + status |= intc_irqpin_irq_handler(irq, &p->irq[k]); + } + } + + return status; +} + +static int intc_irqpin_irq_domain_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + struct intc_irqpin_priv *p = h->host_data; + + p->irq[hw].domain_irq = virq; + p->irq[hw].hw_irq = hw; + + intc_irqpin_dbg(&p->irq[hw], "map"); + irq_set_chip_data(virq, h->host_data); + irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq); + set_irq_flags(virq, IRQF_VALID); /* kill me now */ + return 0; +} + +static struct irq_domain_ops intc_irqpin_irq_domain_ops = { + .map = intc_irqpin_irq_domain_map, + .xlate = irq_domain_xlate_twocell, +}; + +static const struct intc_irqpin_irlm_config intc_irqpin_irlm_r8a7779 = { + .irlm_bit = 23, /* ICR0.IRLM0 */ +}; + +static const struct of_device_id intc_irqpin_dt_ids[] = { + { .compatible = "renesas,intc-irqpin", }, + { .compatible = "renesas,intc-irqpin-r8a7779", + .data = &intc_irqpin_irlm_r8a7779 }, + {}, +}; +MODULE_DEVICE_TABLE(of, intc_irqpin_dt_ids); + +static int intc_irqpin_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct renesas_intc_irqpin_config *pdata = dev->platform_data; + const struct of_device_id *of_id; + struct intc_irqpin_priv *p; + struct intc_irqpin_iomem *i; + struct resource *io[INTC_IRQPIN_REG_NR]; + struct resource *irq; + struct irq_chip *irq_chip; + void (*enable_fn)(struct irq_data *d); + void (*disable_fn)(struct irq_data *d); + const char *name = dev_name(dev); + int ref_irq; + int ret; + int k; + + p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); + if (!p) { + dev_err(dev, "failed to allocate driver data\n"); + return -ENOMEM; + } + + /* deal with driver instance configuration */ + if (pdata) { + memcpy(&p->config, pdata, sizeof(*pdata)); + } else { + of_property_read_u32(dev->of_node, "sense-bitfield-width", + &p->config.sense_bitfield_width); + p->config.control_parent = of_property_read_bool(dev->of_node, + "control-parent"); + } + if (!p->config.sense_bitfield_width) + p->config.sense_bitfield_width = 4; /* default to 4 bits */ + + p->pdev = pdev; + platform_set_drvdata(pdev, p); + + p->clk = devm_clk_get(dev, NULL); + if (IS_ERR(p->clk)) { + dev_warn(dev, "unable to get clock\n"); + p->clk = NULL; + } + + pm_runtime_enable(dev); + pm_runtime_get_sync(dev); + + /* get hold of register banks */ + memset(io, 0, sizeof(io)); + for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { + io[k] = platform_get_resource(pdev, IORESOURCE_MEM, k); + if (!io[k] && k < INTC_IRQPIN_REG_NR_MANDATORY) { + dev_err(dev, "not enough IOMEM resources\n"); + ret = -EINVAL; + goto err0; + } + } + + /* allow any number of IRQs between 1 and INTC_IRQPIN_MAX */ + for (k = 0; k < INTC_IRQPIN_MAX; k++) { + irq = platform_get_resource(pdev, IORESOURCE_IRQ, k); + if (!irq) + break; + + p->irq[k].p = p; + p->irq[k].requested_irq = irq->start; + } + + p->number_of_irqs = k; + if (p->number_of_irqs < 1) { + dev_err(dev, "not enough IRQ resources\n"); + ret = -EINVAL; + goto err0; + } + + /* ioremap IOMEM and setup read/write callbacks */ + for (k = 0; k < INTC_IRQPIN_REG_NR; k++) { + i = &p->iomem[k]; + + /* handle optional registers */ + if (!io[k]) + continue; + + switch (resource_size(io[k])) { + case 1: + i->width = 8; + i->read = intc_irqpin_read8; + i->write = intc_irqpin_write8; + break; + case 4: + i->width = 32; + i->read = intc_irqpin_read32; + i->write = intc_irqpin_write32; + break; + default: + dev_err(dev, "IOMEM size mismatch\n"); + ret = -EINVAL; + goto err0; + } + + i->iomem = devm_ioremap_nocache(dev, io[k]->start, + resource_size(io[k])); + if (!i->iomem) { + dev_err(dev, "failed to remap IOMEM\n"); + ret = -ENXIO; + goto err0; + } + } + + /* configure "individual IRQ mode" where needed */ + of_id = of_match_device(intc_irqpin_dt_ids, dev); + if (of_id && of_id->data) { + const struct intc_irqpin_irlm_config *irlm_config = of_id->data; + + if (io[INTC_IRQPIN_REG_IRLM]) + intc_irqpin_read_modify_write(p, INTC_IRQPIN_REG_IRLM, + irlm_config->irlm_bit, + 1, 1); + else + dev_warn(dev, "unable to select IRLM mode\n"); + } + + /* mask all interrupts using priority */ + for (k = 0; k < p->number_of_irqs; k++) + intc_irqpin_mask_unmask_prio(p, k, 1); + + /* clear all pending interrupts */ + intc_irqpin_write(p, INTC_IRQPIN_REG_SOURCE, 0x0); + + /* scan for shared interrupt lines */ + ref_irq = p->irq[0].requested_irq; + p->shared_irqs = true; + for (k = 1; k < p->number_of_irqs; k++) { + if (ref_irq != p->irq[k].requested_irq) { + p->shared_irqs = false; + break; + } + } + + /* use more severe masking method if requested */ + if (p->config.control_parent) { + enable_fn = intc_irqpin_irq_enable_force; + disable_fn = intc_irqpin_irq_disable_force; + } else if (!p->shared_irqs) { + enable_fn = intc_irqpin_irq_enable; + disable_fn = intc_irqpin_irq_disable; + } else { + enable_fn = intc_irqpin_shared_irq_enable; + disable_fn = intc_irqpin_shared_irq_disable; + } + + irq_chip = &p->irq_chip; + irq_chip->name = name; + irq_chip->irq_mask = disable_fn; + irq_chip->irq_unmask = enable_fn; + irq_chip->irq_set_type = intc_irqpin_irq_set_type; + irq_chip->irq_set_wake = intc_irqpin_irq_set_wake; + irq_chip->flags = IRQCHIP_MASK_ON_SUSPEND; + + p->irq_domain = irq_domain_add_simple(dev->of_node, + p->number_of_irqs, + p->config.irq_base, + &intc_irqpin_irq_domain_ops, p); + if (!p->irq_domain) { + ret = -ENXIO; + dev_err(dev, "cannot initialize irq domain\n"); + goto err0; + } + + if (p->shared_irqs) { + /* request one shared interrupt */ + if (devm_request_irq(dev, p->irq[0].requested_irq, + intc_irqpin_shared_irq_handler, + IRQF_SHARED, name, p)) { + dev_err(dev, "failed to request low IRQ\n"); + ret = -ENOENT; + goto err1; + } + } else { + /* request interrupts one by one */ + for (k = 0; k < p->number_of_irqs; k++) { + if (devm_request_irq(dev, p->irq[k].requested_irq, + intc_irqpin_irq_handler, 0, name, + &p->irq[k])) { + dev_err(dev, "failed to request low IRQ\n"); + ret = -ENOENT; + goto err1; + } + } + } + + /* unmask all interrupts on prio level */ + for (k = 0; k < p->number_of_irqs; k++) + intc_irqpin_mask_unmask_prio(p, k, 0); + + dev_info(dev, "driving %d irqs\n", p->number_of_irqs); + + /* warn in case of mismatch if irq base is specified */ + if (p->config.irq_base) { + if (p->config.irq_base != p->irq[0].domain_irq) + dev_warn(dev, "irq base mismatch (%d/%d)\n", + p->config.irq_base, p->irq[0].domain_irq); + } + + return 0; + +err1: + irq_domain_remove(p->irq_domain); +err0: + pm_runtime_put(dev); + pm_runtime_disable(dev); + return ret; +} + +static int intc_irqpin_remove(struct platform_device *pdev) +{ + struct intc_irqpin_priv *p = platform_get_drvdata(pdev); + + irq_domain_remove(p->irq_domain); + pm_runtime_put(&pdev->dev); + pm_runtime_disable(&pdev->dev); + return 0; +} + +static struct platform_driver intc_irqpin_device_driver = { + .probe = intc_irqpin_probe, + .remove = intc_irqpin_remove, + .driver = { + .name = "renesas_intc_irqpin", + .of_match_table = intc_irqpin_dt_ids, + } +}; + +static int __init intc_irqpin_init(void) +{ + return platform_driver_register(&intc_irqpin_device_driver); +} +postcore_initcall(intc_irqpin_init); + +static void __exit intc_irqpin_exit(void) +{ + platform_driver_unregister(&intc_irqpin_device_driver); +} +module_exit(intc_irqpin_exit); + +MODULE_AUTHOR("Magnus Damm"); +MODULE_DESCRIPTION("Renesas INTC External IRQ Pin Driver"); +MODULE_LICENSE("GPL v2"); |