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Release 4.14 drivers/irqchip/irq-crossbar.c

Directory: drivers/irqchip
/*
 *  drivers/irqchip/irq-crossbar.c
 *
 *  Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
 *  Author: Sricharan R <r.sricharan@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/slab.h>


#define IRQ_FREE	-1

#define IRQ_RESERVED	-2

#define IRQ_SKIP	-3

#define GIC_IRQ_START	32

/**
 * struct crossbar_device - crossbar device description
 * @lock: spinlock serializing access to @irq_map
 * @int_max: maximum number of supported interrupts
 * @safe_map: safe default value to initialize the crossbar
 * @max_crossbar_sources: Maximum number of crossbar sources
 * @irq_map: array of interrupts to crossbar number mapping
 * @crossbar_base: crossbar base address
 * @register_offsets: offsets for each irq number
 * @write: register write function pointer
 */

struct crossbar_device {
	
raw_spinlock_t lock;
	
uint int_max;
	
uint safe_map;
	
uint max_crossbar_sources;
	
uint *irq_map;
	
void __iomem *crossbar_base;
	
int *register_offsets;
	
void (*write)(int, int);
};


static struct crossbar_device *cb;


static void crossbar_writel(int irq_no, int cb_no) { writel(cb_no, cb->crossbar_base + cb->register_offsets[irq_no]); }

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R Sricharan28100.00%1100.00%
Total28100.00%1100.00%


static void crossbar_writew(int irq_no, int cb_no) { writew(cb_no, cb->crossbar_base + cb->register_offsets[irq_no]); }

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static void crossbar_writeb(int irq_no, int cb_no) { writeb(cb_no, cb->crossbar_base + cb->register_offsets[irq_no]); }

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static struct irq_chip crossbar_chip = { .name = "CBAR", .irq_eoi = irq_chip_eoi_parent, .irq_mask = irq_chip_mask_parent, .irq_unmask = irq_chip_unmask_parent, .irq_retrigger = irq_chip_retrigger_hierarchy, .irq_set_type = irq_chip_set_type_parent, .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE, #ifdef CONFIG_SMP .irq_set_affinity = irq_chip_set_affinity_parent, #endif };
static int allocate_gic_irq(struct irq_domain *domain, unsigned virq, irq_hw_number_t hwirq) { struct irq_fwspec fwspec; int i; int err; if (!irq_domain_get_of_node(domain->parent)) return -EINVAL; raw_spin_lock(&cb->lock); for (i = cb->int_max - 1; i >= 0; i--) { if (cb->irq_map[i] == IRQ_FREE) { cb->irq_map[i] = hwirq; break; } } raw_spin_unlock(&cb->lock); if (i < 0) return -ENODEV; fwspec.fwnode = domain->parent->fwnode; fwspec.param_count = 3; fwspec.param[0] = 0; /* SPI */ fwspec.param[1] = i; fwspec.param[2] = IRQ_TYPE_LEVEL_HIGH; err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); if (err) cb->irq_map[i] = IRQ_FREE; else cb->write(i, hwirq); return err; }

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Marc Zyngier12966.84%233.33%
R Sricharan4523.32%116.67%
Nishanth Menon199.84%350.00%
Total193100.00%6100.00%


static int crossbar_domain_alloc(struct irq_domain *d, unsigned int virq, unsigned int nr_irqs, void *data) { struct irq_fwspec *fwspec = data; irq_hw_number_t hwirq; int i; if (fwspec->param_count != 3) return -EINVAL; /* Not GIC compliant */ if (fwspec->param[0] != 0) return -EINVAL; /* No PPI should point to this domain */ hwirq = fwspec->param[1]; if ((hwirq + nr_irqs) > cb->max_crossbar_sources) return -EINVAL; /* Can't deal with this */ for (i = 0; i < nr_irqs; i++) { int err = allocate_gic_irq(d, virq + i, hwirq + i); if (err) return err; irq_domain_set_hwirq_and_chip(d, virq + i, hwirq + i, &crossbar_chip, NULL); } return 0; }

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Marc Zyngier12382.00%250.00%
R Sricharan2516.67%125.00%
Nishanth Menon21.33%125.00%
Total150100.00%4100.00%

/** * crossbar_domain_free - unmap/free a crossbar<->irq connection * @domain: domain of irq to unmap * @virq: virq number * @nr_irqs: number of irqs to free * * We do not maintain a use count of total number of map/unmap * calls for a particular irq to find out if a irq can be really * unmapped. This is because unmap is called during irq_dispose_mapping(irq), * after which irq is anyways unusable. So an explicit map has to be called * after that. */
static void crossbar_domain_free(struct irq_domain *domain, unsigned int virq, unsigned int nr_irqs) { int i; raw_spin_lock(&cb->lock); for (i = 0; i < nr_irqs; i++) { struct irq_data *d = irq_domain_get_irq_data(domain, virq + i); irq_domain_reset_irq_data(d); cb->irq_map[d->hwirq] = IRQ_FREE; cb->write(d->hwirq, cb->safe_map); } raw_spin_unlock(&cb->lock); }

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Marc Zyngier5961.46%125.00%
R Sricharan2425.00%125.00%
Nishanth Menon1313.54%250.00%
Total96100.00%4100.00%


static int crossbar_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec, unsigned long *hwirq, unsigned int *type) { if (is_of_node(fwspec->fwnode)) { if (fwspec->param_count != 3) return -EINVAL; /* No PPI should point to this domain */ if (fwspec->param[0] != 0) return -EINVAL; *hwirq = fwspec->param[1]; *type = fwspec->param[2] & IRQ_TYPE_SENSE_MASK; return 0; } return -EINVAL; }

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Marc Zyngier4851.06%333.33%
R Sricharan3031.91%111.11%
Nishanth Menon1414.89%444.44%
Jon Hunter22.13%111.11%
Total94100.00%9100.00%

static const struct irq_domain_ops crossbar_domain_ops = { .alloc = crossbar_domain_alloc, .free = crossbar_domain_free, .translate = crossbar_domain_translate, };
static int __init crossbar_of_init(struct device_node *node) { u32 max = 0, entry, reg_size; int i, size, reserved = 0; const __be32 *irqsr; int ret = -ENOMEM; cb = kzalloc(sizeof(*cb), GFP_KERNEL); if (!cb) return ret; cb->crossbar_base = of_iomap(node, 0); if (!cb->crossbar_base) goto err_cb; of_property_read_u32(node, "ti,max-crossbar-sources", &cb->max_crossbar_sources); if (!cb->max_crossbar_sources) { pr_err("missing 'ti,max-crossbar-sources' property\n"); ret = -EINVAL; goto err_base; } of_property_read_u32(node, "ti,max-irqs", &max); if (!max) { pr_err("missing 'ti,max-irqs' property\n"); ret = -EINVAL; goto err_base; } cb->irq_map = kcalloc(max, sizeof(int), GFP_KERNEL); if (!cb->irq_map) goto err_base; cb->int_max = max; for (i = 0; i < max; i++) cb->irq_map[i] = IRQ_FREE; /* Get and mark reserved irqs */ irqsr = of_get_property(node, "ti,irqs-reserved", &size); if (irqsr) { size /= sizeof(__be32); for (i = 0; i < size; i++) { of_property_read_u32_index(node, "ti,irqs-reserved", i, &entry); if (entry >= max) { pr_err("Invalid reserved entry\n"); ret = -EINVAL; goto err_irq_map; } cb->irq_map[entry] = IRQ_RESERVED; } } /* Skip irqs hardwired to bypass the crossbar */ irqsr = of_get_property(node, "ti,irqs-skip", &size); if (irqsr) { size /= sizeof(__be32); for (i = 0; i < size; i++) { of_property_read_u32_index(node, "ti,irqs-skip", i, &entry); if (entry >= max) { pr_err("Invalid skip entry\n"); ret = -EINVAL; goto err_irq_map; } cb->irq_map[entry] = IRQ_SKIP; } } cb->register_offsets = kcalloc(max, sizeof(int), GFP_KERNEL); if (!cb->register_offsets) goto err_irq_map; of_property_read_u32(node, "ti,reg-size", &reg_size); switch (reg_size) { case 1: cb->write = crossbar_writeb; break; case 2: cb->write = crossbar_writew; break; case 4: cb->write = crossbar_writel; break; default: pr_err("Invalid reg-size property\n"); ret = -EINVAL; goto err_reg_offset; break; } /* * Register offsets are not linear because of the * reserved irqs. so find and store the offsets once. */ for (i = 0; i < max; i++) { if (cb->irq_map[i] == IRQ_RESERVED) continue; cb->register_offsets[i] = reserved; reserved += reg_size; } of_property_read_u32(node, "ti,irqs-safe-map", &cb->safe_map); /* Initialize the crossbar with safe map to start with */ for (i = 0; i < max; i++) { if (cb->irq_map[i] == IRQ_RESERVED || cb->irq_map[i] == IRQ_SKIP) continue; cb->write(i, cb->safe_map); } raw_spin_lock_init(&cb->lock); return 0; err_reg_offset: kfree(cb->register_offsets); err_irq_map: kfree(cb->irq_map); err_base: iounmap(cb->crossbar_base); err_cb: kfree(cb); cb = NULL; return ret; }

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R Sricharan35959.14%213.33%
Nishanth Menon23238.22%746.67%
Franck Demathieu91.48%320.00%
Marc Zyngier40.66%16.67%
Dan Carpenter30.49%213.33%
Total607100.00%15100.00%


static int __init irqcrossbar_init(struct device_node *node, struct device_node *parent) { struct irq_domain *parent_domain, *domain; int err; if (!parent) { pr_err("%pOF: no parent, giving up\n", node); return -ENODEV; } parent_domain = irq_find_host(parent); if (!parent_domain) { pr_err("%pOF: unable to obtain parent domain\n", node); return -ENXIO; } err = crossbar_of_init(node); if (err) return err; domain = irq_domain_add_hierarchy(parent_domain, 0, cb->max_crossbar_sources, node, &crossbar_domain_ops, NULL); if (!domain) { pr_err("%pOF: failed to allocated domain\n", node); return -ENOMEM; } return 0; }

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Marc Zyngier9575.40%133.33%
R Sricharan2822.22%133.33%
Rob Herring32.38%133.33%
Total126100.00%3100.00%

IRQCHIP_DECLARE(ti_irqcrossbar, "ti,irq-crossbar", irqcrossbar_init);

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R Sricharan67043.96%27.14%
Marc Zyngier52034.12%310.71%
Nishanth Menon30119.75%1242.86%
Grygorii Strashko110.72%310.71%
Franck Demathieu90.59%310.71%
Joël Porquet50.33%13.57%
Rob Herring30.20%13.57%
Dan Carpenter30.20%27.14%
Jon Hunter20.13%13.57%
Total1524100.00%28100.00%
Directory: drivers/irqchip
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