diff options
author | Talel Shenhar <talel@amazon.com> | 2019-06-10 11:34:43 +0300 |
---|---|---|
committer | Marc Zyngier <marc.zyngier@arm.com> | 2019-07-03 09:19:11 +0100 |
commit | 1eb77c3bcdb70f2501f419b3da45b19acaf01072 (patch) | |
tree | 7edfbadb265ac6c597f22527f9e34a4f99ca5f1e /drivers/irqchip/irq-al-fic.c | |
parent | 74b5150cde45ab29ee332a3d1e770c00431f7993 (diff) | |
download | linux-1eb77c3bcdb70f2501f419b3da45b19acaf01072.tar.gz linux-1eb77c3bcdb70f2501f419b3da45b19acaf01072.tar.bz2 linux-1eb77c3bcdb70f2501f419b3da45b19acaf01072.zip |
irqchip/al-fic: Introduce Amazon's Annapurna Labs Fabric Interrupt Controller Driver
The Amazon's Annapurna Labs Fabric Interrupt Controller has 32 inputs.
A FIC (Fabric Interrupt Controller) may be cascaded into another FIC or
directly to the main CPU Interrupt Controller (e.g. GIC).
Signed-off-by: Talel Shenhar <talel@amazon.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'drivers/irqchip/irq-al-fic.c')
-rw-r--r-- | drivers/irqchip/irq-al-fic.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-al-fic.c b/drivers/irqchip/irq-al-fic.c new file mode 100644 index 000000000000..1a57cee3efab --- /dev/null +++ b/drivers/irqchip/irq-al-fic.c @@ -0,0 +1,278 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. + */ + +#include <linux/bitfield.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> + +/* FIC Registers */ +#define AL_FIC_CAUSE 0x00 +#define AL_FIC_MASK 0x10 +#define AL_FIC_CONTROL 0x28 + +#define CONTROL_TRIGGER_RISING BIT(3) +#define CONTROL_MASK_MSI_X BIT(5) + +#define NR_FIC_IRQS 32 + +MODULE_AUTHOR("Talel Shenhar"); +MODULE_DESCRIPTION("Amazon's Annapurna Labs Interrupt Controller Driver"); +MODULE_LICENSE("GPL v2"); + +enum al_fic_state { + AL_FIC_UNCONFIGURED = 0, + AL_FIC_CONFIGURED_LEVEL, + AL_FIC_CONFIGURED_RISING_EDGE, +}; + +struct al_fic { + void __iomem *base; + struct irq_domain *domain; + const char *name; + unsigned int parent_irq; + enum al_fic_state state; +}; + +static void al_fic_set_trigger(struct al_fic *fic, + struct irq_chip_generic *gc, + enum al_fic_state new_state) +{ + irq_flow_handler_t handler; + u32 control = readl_relaxed(fic->base + AL_FIC_CONTROL); + + if (new_state == AL_FIC_CONFIGURED_LEVEL) { + handler = handle_level_irq; + control &= ~CONTROL_TRIGGER_RISING; + } else { + handler = handle_edge_irq; + control |= CONTROL_TRIGGER_RISING; + } + gc->chip_types->handler = handler; + fic->state = new_state; + writel_relaxed(control, fic->base + AL_FIC_CONTROL); +} + +static int al_fic_irq_set_type(struct irq_data *data, unsigned int flow_type) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data); + struct al_fic *fic = gc->private; + enum al_fic_state new_state; + int ret = 0; + + irq_gc_lock(gc); + + if (((flow_type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_HIGH) && + ((flow_type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_EDGE_RISING)) { + pr_debug("fic doesn't support flow type %d\n", flow_type); + ret = -EINVAL; + goto err; + } + + new_state = (flow_type & IRQ_TYPE_LEVEL_HIGH) ? + AL_FIC_CONFIGURED_LEVEL : AL_FIC_CONFIGURED_RISING_EDGE; + + /* + * A given FIC instance can be either all level or all edge triggered. + * This is generally fixed depending on what pieces of HW it's wired up + * to. + * + * We configure it based on the sensitivity of the first source + * being setup, and reject any subsequent attempt at configuring it in a + * different way. + */ + if (fic->state == AL_FIC_UNCONFIGURED) { + al_fic_set_trigger(fic, gc, new_state); + } else if (fic->state != new_state) { + pr_debug("fic %s state already configured to %d\n", + fic->name, fic->state); + ret = -EINVAL; + goto err; + } + +err: + irq_gc_unlock(gc); + + return ret; +} + +static void al_fic_irq_handler(struct irq_desc *desc) +{ + struct al_fic *fic = irq_desc_get_handler_data(desc); + struct irq_domain *domain = fic->domain; + struct irq_chip *irqchip = irq_desc_get_chip(desc); + struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0); + unsigned long pending; + unsigned int irq; + u32 hwirq; + + chained_irq_enter(irqchip, desc); + + pending = readl_relaxed(fic->base + AL_FIC_CAUSE); + pending &= ~gc->mask_cache; + + for_each_set_bit(hwirq, &pending, NR_FIC_IRQS) { + irq = irq_find_mapping(domain, hwirq); + generic_handle_irq(irq); + } + + chained_irq_exit(irqchip, desc); +} + +static int al_fic_register(struct device_node *node, + struct al_fic *fic) +{ + struct irq_chip_generic *gc; + int ret; + + fic->domain = irq_domain_add_linear(node, + NR_FIC_IRQS, + &irq_generic_chip_ops, + fic); + if (!fic->domain) { + pr_err("fail to add irq domain\n"); + return -ENOMEM; + } + + ret = irq_alloc_domain_generic_chips(fic->domain, + NR_FIC_IRQS, + 1, fic->name, + handle_level_irq, + 0, 0, IRQ_GC_INIT_MASK_CACHE); + if (ret) { + pr_err("fail to allocate generic chip (%d)\n", ret); + goto err_domain_remove; + } + + gc = irq_get_domain_generic_chip(fic->domain, 0); + gc->reg_base = fic->base; + gc->chip_types->regs.mask = AL_FIC_MASK; + gc->chip_types->regs.ack = AL_FIC_CAUSE; + gc->chip_types->chip.irq_mask = irq_gc_mask_set_bit; + gc->chip_types->chip.irq_unmask = irq_gc_mask_clr_bit; + gc->chip_types->chip.irq_ack = irq_gc_ack_clr_bit; + gc->chip_types->chip.irq_set_type = al_fic_irq_set_type; + gc->chip_types->chip.flags = IRQCHIP_SKIP_SET_WAKE; + gc->private = fic; + + irq_set_chained_handler_and_data(fic->parent_irq, + al_fic_irq_handler, + fic); + return 0; + +err_domain_remove: + irq_domain_remove(fic->domain); + + return ret; +} + +/* + * al_fic_wire_init() - initialize and configure fic in wire mode + * @of_node: optional pointer to interrupt controller's device tree node. + * @base: mmio to fic register + * @name: name of the fic + * @parent_irq: interrupt of parent + * + * This API will configure the fic hardware to to work in wire mode. + * In wire mode, fic hardware is generating a wire ("wired") interrupt. + * Interrupt can be generated based on positive edge or level - configuration is + * to be determined based on connected hardware to this fic. + */ +static struct al_fic *al_fic_wire_init(struct device_node *node, + void __iomem *base, + const char *name, + unsigned int parent_irq) +{ + struct al_fic *fic; + int ret; + u32 control = CONTROL_MASK_MSI_X; + + fic = kzalloc(sizeof(*fic), GFP_KERNEL); + if (!fic) + return ERR_PTR(-ENOMEM); + + fic->base = base; + fic->parent_irq = parent_irq; + fic->name = name; + + /* mask out all interrupts */ + writel_relaxed(0xFFFFFFFF, fic->base + AL_FIC_MASK); + + /* clear any pending interrupt */ + writel_relaxed(0, fic->base + AL_FIC_CAUSE); + + writel_relaxed(control, fic->base + AL_FIC_CONTROL); + + ret = al_fic_register(node, fic); + if (ret) { + pr_err("fail to register irqchip\n"); + goto err_free; + } + + pr_debug("%s initialized successfully in Legacy mode (parent-irq=%u)\n", + fic->name, parent_irq); + + return fic; + +err_free: + kfree(fic); + return ERR_PTR(ret); +} + +static int __init al_fic_init_dt(struct device_node *node, + struct device_node *parent) +{ + int ret; + void __iomem *base; + unsigned int parent_irq; + struct al_fic *fic; + + if (!parent) { + pr_err("%s: unsupported - device require a parent\n", + node->name); + return -EINVAL; + } + + base = of_iomap(node, 0); + if (!base) { + pr_err("%s: fail to map memory\n", node->name); + return -ENOMEM; + } + + parent_irq = irq_of_parse_and_map(node, 0); + if (!parent_irq) { + pr_err("%s: fail to map irq\n", node->name); + ret = -EINVAL; + goto err_unmap; + } + + fic = al_fic_wire_init(node, + base, + node->name, + parent_irq); + if (IS_ERR(fic)) { + pr_err("%s: fail to initialize irqchip (%lu)\n", + node->name, + PTR_ERR(fic)); + ret = PTR_ERR(fic); + goto err_irq_dispose; + } + + return 0; + +err_irq_dispose: + irq_dispose_mapping(parent_irq); +err_unmap: + iounmap(base); + + return ret; +} + +IRQCHIP_DECLARE(al_fic, "amazon,al-fic", al_fic_init_dt); |