diff options
Diffstat (limited to 'drivers/irqchip/irq-imx-intmux.c')
| -rw-r--r-- | drivers/irqchip/irq-imx-intmux.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-imx-intmux.c b/drivers/irqchip/irq-imx-intmux.c new file mode 100644 index 000000000000..c27577c81126 --- /dev/null +++ b/drivers/irqchip/irq-imx-intmux.c @@ -0,0 +1,309 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright 2017 NXP + +/* INTMUX Block Diagram + * + * ________________ + * interrupt source # 0 +---->| | + * | | | + * interrupt source # 1 +++-->| | + * ... | | | channel # 0 |--------->interrupt out # 0 + * ... | | | | + * ... | | | | + * interrupt source # X-1 +++-->|________________| + * | | | + * | | | + * | | | ________________ + * +---->| | + * | | | | | + * | +-->| | + * | | | | channel # 1 |--------->interrupt out # 1 + * | | +>| | + * | | | | | + * | | | |________________| + * | | | + * | | | + * | | | ... + * | | | ... + * | | | + * | | | ________________ + * +---->| | + * | | | | + * +-->| | + * | | channel # N |--------->interrupt out # N + * +>| | + * | | + * |________________| + * + * + * N: Interrupt Channel Instance Number (N=7) + * X: Interrupt Source Number for each channel (X=32) + * + * The INTMUX interrupt multiplexer has 8 channels, each channel receives 32 + * interrupt sources and generates 1 interrupt output. + * + */ + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/spinlock.h> + +#define CHANIER(n) (0x10 + (0x40 * n)) +#define CHANIPR(n) (0x20 + (0x40 * n)) + +#define CHAN_MAX_NUM 0x8 + +struct intmux_irqchip_data { + int chanidx; + int irq; + struct irq_domain *domain; +}; + +struct intmux_data { + raw_spinlock_t lock; + void __iomem *regs; + struct clk *ipg_clk; + int channum; + struct intmux_irqchip_data irqchip_data[]; +}; + +static void imx_intmux_irq_mask(struct irq_data *d) +{ + struct intmux_irqchip_data *irqchip_data = d->chip_data; + int idx = irqchip_data->chanidx; + struct intmux_data *data = container_of(irqchip_data, struct intmux_data, + irqchip_data[idx]); + unsigned long flags; + void __iomem *reg; + u32 val; + + raw_spin_lock_irqsave(&data->lock, flags); + reg = data->regs + CHANIER(idx); + val = readl_relaxed(reg); + /* disable the interrupt source of this channel */ + val &= ~BIT(d->hwirq); + writel_relaxed(val, reg); + raw_spin_unlock_irqrestore(&data->lock, flags); +} + +static void imx_intmux_irq_unmask(struct irq_data *d) +{ + struct intmux_irqchip_data *irqchip_data = d->chip_data; + int idx = irqchip_data->chanidx; + struct intmux_data *data = container_of(irqchip_data, struct intmux_data, + irqchip_data[idx]); + unsigned long flags; + void __iomem *reg; + u32 val; + + raw_spin_lock_irqsave(&data->lock, flags); + reg = data->regs + CHANIER(idx); + val = readl_relaxed(reg); + /* enable the interrupt source of this channel */ + val |= BIT(d->hwirq); + writel_relaxed(val, reg); + raw_spin_unlock_irqrestore(&data->lock, flags); +} + +static struct irq_chip imx_intmux_irq_chip = { + .name = "intmux", + .irq_mask = imx_intmux_irq_mask, + .irq_unmask = imx_intmux_irq_unmask, +}; + +static int imx_intmux_irq_map(struct irq_domain *h, unsigned int irq, + irq_hw_number_t hwirq) +{ + irq_set_chip_data(irq, h->host_data); + irq_set_chip_and_handler(irq, &imx_intmux_irq_chip, handle_level_irq); + + return 0; +} + +static int imx_intmux_irq_xlate(struct irq_domain *d, struct device_node *node, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + struct intmux_irqchip_data *irqchip_data = d->host_data; + int idx = irqchip_data->chanidx; + struct intmux_data *data = container_of(irqchip_data, struct intmux_data, + irqchip_data[idx]); + + /* + * two cells needed in interrupt specifier: + * the 1st cell: hw interrupt number + * the 2nd cell: channel index + */ + if (WARN_ON(intsize != 2)) + return -EINVAL; + + if (WARN_ON(intspec[1] >= data->channum)) + return -EINVAL; + + *out_hwirq = intspec[0]; + *out_type = IRQ_TYPE_LEVEL_HIGH; + + return 0; +} + +static int imx_intmux_irq_select(struct irq_domain *d, struct irq_fwspec *fwspec, + enum irq_domain_bus_token bus_token) +{ + struct intmux_irqchip_data *irqchip_data = d->host_data; + + /* Not for us */ + if (fwspec->fwnode != d->fwnode) + return false; + + return irqchip_data->chanidx == fwspec->param[1]; +} + +static const struct irq_domain_ops imx_intmux_domain_ops = { + .map = imx_intmux_irq_map, + .xlate = imx_intmux_irq_xlate, + .select = imx_intmux_irq_select, +}; + +static void imx_intmux_irq_handler(struct irq_desc *desc) +{ + struct intmux_irqchip_data *irqchip_data = irq_desc_get_handler_data(desc); + int idx = irqchip_data->chanidx; + struct intmux_data *data = container_of(irqchip_data, struct intmux_data, + irqchip_data[idx]); + unsigned long irqstat; + int pos, virq; + + chained_irq_enter(irq_desc_get_chip(desc), desc); + + /* read the interrupt source pending status of this channel */ + irqstat = readl_relaxed(data->regs + CHANIPR(idx)); + + for_each_set_bit(pos, &irqstat, 32) { + virq = irq_find_mapping(irqchip_data->domain, pos); + if (virq) + generic_handle_irq(virq); + } + + chained_irq_exit(irq_desc_get_chip(desc), desc); +} + +static int imx_intmux_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct irq_domain *domain; + struct intmux_data *data; + int channum; + int i, ret; + + channum = platform_irq_count(pdev); + if (channum == -EPROBE_DEFER) { + return -EPROBE_DEFER; + } else if (channum > CHAN_MAX_NUM) { + dev_err(&pdev->dev, "supports up to %d multiplex channels\n", + CHAN_MAX_NUM); + return -EINVAL; + } + + data = devm_kzalloc(&pdev->dev, sizeof(*data) + + channum * sizeof(data->irqchip_data[0]), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regs = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(data->regs)) { + dev_err(&pdev->dev, "failed to initialize reg\n"); + return PTR_ERR(data->regs); + } + + data->ipg_clk = devm_clk_get(&pdev->dev, "ipg"); + if (IS_ERR(data->ipg_clk)) { + ret = PTR_ERR(data->ipg_clk); + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "failed to get ipg clk: %d\n", ret); + return ret; + } + + data->channum = channum; + raw_spin_lock_init(&data->lock); + + ret = clk_prepare_enable(data->ipg_clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable ipg clk: %d\n", ret); + return ret; + } + + for (i = 0; i < channum; i++) { + data->irqchip_data[i].chanidx = i; + + data->irqchip_data[i].irq = irq_of_parse_and_map(np, i); + if (data->irqchip_data[i].irq <= 0) { + ret = -EINVAL; + dev_err(&pdev->dev, "failed to get irq\n"); + goto out; + } + + domain = irq_domain_add_linear(np, 32, &imx_intmux_domain_ops, + &data->irqchip_data[i]); + if (!domain) { + ret = -ENOMEM; + dev_err(&pdev->dev, "failed to create IRQ domain\n"); + goto out; + } + data->irqchip_data[i].domain = domain; + + /* disable all interrupt sources of this channel firstly */ + writel_relaxed(0, data->regs + CHANIER(i)); + + irq_set_chained_handler_and_data(data->irqchip_data[i].irq, + imx_intmux_irq_handler, + &data->irqchip_data[i]); + } + + platform_set_drvdata(pdev, data); + + return 0; +out: + clk_disable_unprepare(data->ipg_clk); + return ret; +} + +static int imx_intmux_remove(struct platform_device *pdev) +{ + struct intmux_data *data = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < data->channum; i++) { + /* disable all interrupt sources of this channel */ + writel_relaxed(0, data->regs + CHANIER(i)); + + irq_set_chained_handler_and_data(data->irqchip_data[i].irq, + NULL, NULL); + + irq_domain_remove(data->irqchip_data[i].domain); + } + + clk_disable_unprepare(data->ipg_clk); + + return 0; +} + +static const struct of_device_id imx_intmux_id[] = { + { .compatible = "fsl,imx-intmux", }, + { /* sentinel */ }, +}; + +static struct platform_driver imx_intmux_driver = { + .driver = { + .name = "imx-intmux", + .of_match_table = imx_intmux_id, + }, + .probe = imx_intmux_probe, + .remove = imx_intmux_remove, +}; +builtin_platform_driver(imx_intmux_driver); |