diff options
Diffstat (limited to 'drivers/irqchip/irq-vf610-gpc.c')
| -rw-r--r-- | drivers/irqchip/irq-vf610-gpc.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-vf610-gpc.c b/drivers/irqchip/irq-vf610-gpc.c new file mode 100644 index 000000000000..105a6606e425 --- /dev/null +++ b/drivers/irqchip/irq-vf610-gpc.c @@ -0,0 +1,138 @@ +/* + * Copyright (C) 2015 Toradex AG + * Author: Stefan Agner <stefan@agner.ch> + * + * 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. + * + * + * The GPC (General Power Controller) irqchip driver takes care of the + * interrupt wakeup functionality. + * + * o All peripheral interrupts of the Vybrid SoC can be used as wakeup + * source from STOP mode. In LPSTOP mode however, the GPC is unpowered + * too and cannot be used to as a wakeup source. The WKPU (Wakeup Unit) + * is responsible for wakeups from LPSTOP modes. + */ + +#include <linux/cpu_pm.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> +#include <linux/mfd/syscon.h> +#include <dt-bindings/interrupt-controller/arm-gic.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <linux/regmap.h> + +#define IMR_NUM 4 +#define VF610_GPC_IMR1 0x044 +#define VF610_GPC_MAX_IRQS (IMR_NUM * 32) + +static void __iomem *gpc_base; + +static int vf610_gpc_irq_set_wake(struct irq_data *d, unsigned int on) +{ + unsigned int idx = d->hwirq / 32; + void __iomem *reg_imr = gpc_base + VF610_GPC_IMR1 + (idx * 4); + u32 mask = 1 << d->hwirq % 32; + + if (on) + writel_relaxed(readl_relaxed(reg_imr) & ~mask, reg_imr); + else + writel_relaxed(readl_relaxed(reg_imr) | mask, reg_imr); + + /* + * Do *not* call into the parent, as the GIC doesn't have any + * wake-up facility... + */ + return 0; +} + +static struct irq_chip vf610_gpc_chip = { + .name = "vf610-gpc", + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_enable = irq_chip_enable_parent, + .irq_disable = irq_chip_disable_parent, + .irq_eoi = irq_chip_eoi_parent, + .irq_retrigger = irq_chip_retrigger_hierarchy, + .irq_set_wake = vf610_gpc_irq_set_wake, +}; + +static int vf610_gpc_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + int i; + irq_hw_number_t hwirq; + struct irq_fwspec *fwspec = arg; + struct irq_fwspec parent_fwspec; + + if (!irq_domain_get_of_node(domain->parent)) + return -EINVAL; + + if (fwspec->param_count != 2) + return -EINVAL; + + hwirq = fwspec->param[0]; + for (i = 0; i < nr_irqs; i++) + irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i, + &vf610_gpc_chip, NULL); + + parent_fwspec = *fwspec; + parent_fwspec.fwnode = domain->parent->fwnode; + return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, + &parent_fwspec); +} + +static int vf610_gpc_domain_translate(struct irq_domain *d, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + if (WARN_ON(fwspec->param_count < 2)) + return -EINVAL; + *hwirq = fwspec->param[0]; + *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK; + return 0; +} + +static const struct irq_domain_ops gpc_irq_domain_ops = { + .translate = vf610_gpc_domain_translate, + .alloc = vf610_gpc_domain_alloc, + .free = irq_domain_free_irqs_common, +}; + +static int __init vf610_gpc_of_init(struct device_node *node, + struct device_node *parent) +{ + struct irq_domain *domain, *domain_parent; + int i; + + domain_parent = irq_find_host(parent); + if (!domain_parent) { + pr_err("vf610_gpc: interrupt-parent not found\n"); + return -EINVAL; + } + + gpc_base = of_io_request_and_map(node, 0, "gpc"); + if (WARN_ON(!gpc_base)) + return -ENOMEM; + + domain = irq_domain_add_hierarchy(domain_parent, 0, VF610_GPC_MAX_IRQS, + node, &gpc_irq_domain_ops, NULL); + if (!domain) { + iounmap(gpc_base); + return -ENOMEM; + } + + /* Initially mask all interrupts for wakeup */ + for (i = 0; i < IMR_NUM; i++) + writel_relaxed(~0, gpc_base + VF610_GPC_IMR1 + i * 4); + + return 0; +} +IRQCHIP_DECLARE(vf610_gpc, "fsl,vf610-gpc", vf610_gpc_of_init); |