linux/drivers/irqchip/irq-imx-intmux.c
Joakim Zhang 2fbb13961e irqchip: Add NXP INTMUX interrupt multiplexer support
The Interrupt Multiplexer (INTMUX) expands the number of peripherals
that can interrupt the core:
* The INTMUX has 8 channels that are assigned to 8 NVIC interrupt slots.
* Each INTMUX channel can receive up to 32 interrupt sources and has 1
  interrupt output.
* The INTMUX routes the interrupt sources to the interrupt outputs.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200117060653.27485-3-qiangqing.zhang@nxp.com
2020-01-20 19:10:05 +00:00

310 lines
8.4 KiB
C

// 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);