diff options
Diffstat (limited to 'drivers/irqchip/irq-xtensa-mx.c')
| -rw-r--r-- | drivers/irqchip/irq-xtensa-mx.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-xtensa-mx.c b/drivers/irqchip/irq-xtensa-mx.c new file mode 100644 index 0000000000..7f314e58f3 --- /dev/null +++ b/drivers/irqchip/irq-xtensa-mx.c @@ -0,0 +1,186 @@ +/* + * Xtensa MX interrupt distributor + * + * Copyright (C) 2002 - 2013 Tensilica, Inc. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/interrupt.h> +#include <linux/irqdomain.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqchip/xtensa-mx.h> +#include <linux/of.h> + +#include <asm/mxregs.h> + +#define HW_IRQ_IPI_COUNT 2 +#define HW_IRQ_MX_BASE 2 +#define HW_IRQ_EXTERN_BASE 3 + +static DEFINE_PER_CPU(unsigned int, cached_irq_mask); + +static int xtensa_mx_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hw) +{ + if (hw < HW_IRQ_IPI_COUNT) { + struct irq_chip *irq_chip = d->host_data; + irq_set_chip_and_handler_name(irq, irq_chip, + handle_percpu_irq, "ipi"); + irq_set_status_flags(irq, IRQ_LEVEL); + return 0; + } + irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq))); + return xtensa_irq_map(d, irq, hw); +} + +/* + * Device Tree IRQ specifier translation function which works with one or + * two cell bindings. First cell value maps directly to the hwirq number. + * Second cell if present specifies whether hwirq number is external (1) or + * internal (0). + */ +static int xtensa_mx_irq_domain_xlate(struct irq_domain *d, + struct device_node *ctrlr, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + return xtensa_irq_domain_xlate(intspec, intsize, + intspec[0], intspec[0] + HW_IRQ_EXTERN_BASE, + out_hwirq, out_type); +} + +static const struct irq_domain_ops xtensa_mx_irq_domain_ops = { + .xlate = xtensa_mx_irq_domain_xlate, + .map = xtensa_mx_irq_map, +}; + +void secondary_init_irq(void) +{ + __this_cpu_write(cached_irq_mask, + XCHAL_INTTYPE_MASK_EXTERN_EDGE | + XCHAL_INTTYPE_MASK_EXTERN_LEVEL); + xtensa_set_sr(XCHAL_INTTYPE_MASK_EXTERN_EDGE | + XCHAL_INTTYPE_MASK_EXTERN_LEVEL, intenable); +} + +static void xtensa_mx_irq_mask(struct irq_data *d) +{ + unsigned int mask = 1u << d->hwirq; + + if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE | + XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) { + unsigned int ext_irq = xtensa_get_ext_irq_no(d->hwirq); + + if (ext_irq >= HW_IRQ_MX_BASE) { + set_er(1u << (ext_irq - HW_IRQ_MX_BASE), MIENG); + return; + } + } + mask = __this_cpu_read(cached_irq_mask) & ~mask; + __this_cpu_write(cached_irq_mask, mask); + xtensa_set_sr(mask, intenable); +} + +static void xtensa_mx_irq_unmask(struct irq_data *d) +{ + unsigned int mask = 1u << d->hwirq; + + if (mask & (XCHAL_INTTYPE_MASK_EXTERN_EDGE | + XCHAL_INTTYPE_MASK_EXTERN_LEVEL)) { + unsigned int ext_irq = xtensa_get_ext_irq_no(d->hwirq); + + if (ext_irq >= HW_IRQ_MX_BASE) { + set_er(1u << (ext_irq - HW_IRQ_MX_BASE), MIENGSET); + return; + } + } + mask |= __this_cpu_read(cached_irq_mask); + __this_cpu_write(cached_irq_mask, mask); + xtensa_set_sr(mask, intenable); +} + +static void xtensa_mx_irq_enable(struct irq_data *d) +{ + xtensa_mx_irq_unmask(d); +} + +static void xtensa_mx_irq_disable(struct irq_data *d) +{ + xtensa_mx_irq_mask(d); +} + +static void xtensa_mx_irq_ack(struct irq_data *d) +{ + xtensa_set_sr(1 << d->hwirq, intclear); +} + +static int xtensa_mx_irq_retrigger(struct irq_data *d) +{ + unsigned int mask = 1u << d->hwirq; + + if (WARN_ON(mask & ~XCHAL_INTTYPE_MASK_SOFTWARE)) + return 0; + xtensa_set_sr(mask, intset); + return 1; +} + +static int xtensa_mx_irq_set_affinity(struct irq_data *d, + const struct cpumask *dest, bool force) +{ + int cpu = cpumask_any_and(dest, cpu_online_mask); + unsigned mask = 1u << cpu; + + set_er(mask, MIROUT(d->hwirq - HW_IRQ_MX_BASE)); + irq_data_update_effective_affinity(d, cpumask_of(cpu)); + + return 0; + +} + +static struct irq_chip xtensa_mx_irq_chip = { + .name = "xtensa-mx", + .irq_enable = xtensa_mx_irq_enable, + .irq_disable = xtensa_mx_irq_disable, + .irq_mask = xtensa_mx_irq_mask, + .irq_unmask = xtensa_mx_irq_unmask, + .irq_ack = xtensa_mx_irq_ack, + .irq_retrigger = xtensa_mx_irq_retrigger, + .irq_set_affinity = xtensa_mx_irq_set_affinity, +}; + +static void __init xtensa_mx_init_common(struct irq_domain *root_domain) +{ + unsigned int i; + + irq_set_default_host(root_domain); + secondary_init_irq(); + + /* Initialize default IRQ routing to CPU 0 */ + for (i = 0; i < XCHAL_NUM_EXTINTERRUPTS; ++i) + set_er(1, MIROUT(i)); +} + +int __init xtensa_mx_init_legacy(struct device_node *interrupt_parent) +{ + struct irq_domain *root_domain = + irq_domain_add_legacy(NULL, NR_IRQS - 1, 1, 0, + &xtensa_mx_irq_domain_ops, + &xtensa_mx_irq_chip); + xtensa_mx_init_common(root_domain); + return 0; +} + +static int __init xtensa_mx_init(struct device_node *np, + struct device_node *interrupt_parent) +{ + struct irq_domain *root_domain = + irq_domain_add_linear(np, NR_IRQS, &xtensa_mx_irq_domain_ops, + &xtensa_mx_irq_chip); + xtensa_mx_init_common(root_domain); + return 0; +} +IRQCHIP_DECLARE(xtensa_mx_irq_chip, "cdns,xtensa-mx", xtensa_mx_init); |