cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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gpio-idt3243x.c (5318B)


      1// SPDX-License-Identifier: GPL-2.0
      2/* Driver for IDT/Renesas 79RC3243x Interrupt Controller  */
      3
      4#include <linux/bitops.h>
      5#include <linux/gpio/driver.h>
      6#include <linux/irq.h>
      7#include <linux/module.h>
      8#include <linux/mod_devicetable.h>
      9#include <linux/platform_device.h>
     10#include <linux/spinlock.h>
     11
     12#define IDT_PIC_IRQ_PEND	0x00
     13#define IDT_PIC_IRQ_MASK	0x08
     14
     15#define IDT_GPIO_DIR		0x00
     16#define IDT_GPIO_DATA		0x04
     17#define IDT_GPIO_ILEVEL		0x08
     18#define IDT_GPIO_ISTAT		0x0C
     19
     20struct idt_gpio_ctrl {
     21	struct gpio_chip gc;
     22	void __iomem *pic;
     23	void __iomem *gpio;
     24	u32 mask_cache;
     25};
     26
     27static void idt_gpio_dispatch(struct irq_desc *desc)
     28{
     29	struct gpio_chip *gc = irq_desc_get_handler_data(desc);
     30	struct idt_gpio_ctrl *ctrl = gpiochip_get_data(gc);
     31	struct irq_chip *host_chip = irq_desc_get_chip(desc);
     32	unsigned int bit, virq;
     33	unsigned long pending;
     34
     35	chained_irq_enter(host_chip, desc);
     36
     37	pending = readl(ctrl->pic + IDT_PIC_IRQ_PEND);
     38	pending &= ~ctrl->mask_cache;
     39	for_each_set_bit(bit, &pending, gc->ngpio) {
     40		virq = irq_linear_revmap(gc->irq.domain, bit);
     41		if (virq)
     42			generic_handle_irq(virq);
     43	}
     44
     45	chained_irq_exit(host_chip, desc);
     46}
     47
     48static int idt_gpio_irq_set_type(struct irq_data *d, unsigned int flow_type)
     49{
     50	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
     51	struct idt_gpio_ctrl *ctrl = gpiochip_get_data(gc);
     52	unsigned int sense = flow_type & IRQ_TYPE_SENSE_MASK;
     53	unsigned long flags;
     54	u32 ilevel;
     55
     56	/* hardware only supports level triggered */
     57	if (sense == IRQ_TYPE_NONE || (sense & IRQ_TYPE_EDGE_BOTH))
     58		return -EINVAL;
     59
     60	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
     61
     62	ilevel = readl(ctrl->gpio + IDT_GPIO_ILEVEL);
     63	if (sense & IRQ_TYPE_LEVEL_HIGH)
     64		ilevel |= BIT(d->hwirq);
     65	else if (sense & IRQ_TYPE_LEVEL_LOW)
     66		ilevel &= ~BIT(d->hwirq);
     67
     68	writel(ilevel, ctrl->gpio + IDT_GPIO_ILEVEL);
     69	irq_set_handler_locked(d, handle_level_irq);
     70
     71	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
     72	return 0;
     73}
     74
     75static void idt_gpio_ack(struct irq_data *d)
     76{
     77	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
     78	struct idt_gpio_ctrl *ctrl = gpiochip_get_data(gc);
     79
     80	writel(~BIT(d->hwirq), ctrl->gpio + IDT_GPIO_ISTAT);
     81}
     82
     83static void idt_gpio_mask(struct irq_data *d)
     84{
     85	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
     86	struct idt_gpio_ctrl *ctrl = gpiochip_get_data(gc);
     87	unsigned long flags;
     88
     89	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
     90
     91	ctrl->mask_cache |= BIT(d->hwirq);
     92	writel(ctrl->mask_cache, ctrl->pic + IDT_PIC_IRQ_MASK);
     93
     94	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
     95}
     96
     97static void idt_gpio_unmask(struct irq_data *d)
     98{
     99	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
    100	struct idt_gpio_ctrl *ctrl = gpiochip_get_data(gc);
    101	unsigned long flags;
    102
    103	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
    104
    105	ctrl->mask_cache &= ~BIT(d->hwirq);
    106	writel(ctrl->mask_cache, ctrl->pic + IDT_PIC_IRQ_MASK);
    107
    108	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
    109}
    110
    111static int idt_gpio_irq_init_hw(struct gpio_chip *gc)
    112{
    113	struct idt_gpio_ctrl *ctrl = gpiochip_get_data(gc);
    114
    115	/* Mask interrupts. */
    116	ctrl->mask_cache = 0xffffffff;
    117	writel(ctrl->mask_cache, ctrl->pic + IDT_PIC_IRQ_MASK);
    118
    119	return 0;
    120}
    121
    122static struct irq_chip idt_gpio_irqchip = {
    123	.name = "IDTGPIO",
    124	.irq_mask = idt_gpio_mask,
    125	.irq_ack = idt_gpio_ack,
    126	.irq_unmask = idt_gpio_unmask,
    127	.irq_set_type = idt_gpio_irq_set_type
    128};
    129
    130static int idt_gpio_probe(struct platform_device *pdev)
    131{
    132	struct device *dev = &pdev->dev;
    133	struct gpio_irq_chip *girq;
    134	struct idt_gpio_ctrl *ctrl;
    135	int parent_irq;
    136	int ngpios;
    137	int ret;
    138
    139
    140	ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
    141	if (!ctrl)
    142		return -ENOMEM;
    143
    144	ctrl->gpio = devm_platform_ioremap_resource_byname(pdev, "gpio");
    145	if (IS_ERR(ctrl->gpio))
    146		return PTR_ERR(ctrl->gpio);
    147
    148	ctrl->gc.parent = dev;
    149
    150	ret = bgpio_init(&ctrl->gc, &pdev->dev, 4, ctrl->gpio + IDT_GPIO_DATA,
    151			 NULL, NULL, ctrl->gpio + IDT_GPIO_DIR, NULL, 0);
    152	if (ret) {
    153		dev_err(dev, "bgpio_init failed\n");
    154		return ret;
    155	}
    156
    157	ret = device_property_read_u32(dev, "ngpios", &ngpios);
    158	if (!ret)
    159		ctrl->gc.ngpio = ngpios;
    160
    161	if (device_property_read_bool(dev, "interrupt-controller")) {
    162		ctrl->pic = devm_platform_ioremap_resource_byname(pdev, "pic");
    163		if (IS_ERR(ctrl->pic))
    164			return PTR_ERR(ctrl->pic);
    165
    166		parent_irq = platform_get_irq(pdev, 0);
    167		if (parent_irq < 0)
    168			return parent_irq;
    169
    170		girq = &ctrl->gc.irq;
    171		girq->chip = &idt_gpio_irqchip;
    172		girq->init_hw = idt_gpio_irq_init_hw;
    173		girq->parent_handler = idt_gpio_dispatch;
    174		girq->num_parents = 1;
    175		girq->parents = devm_kcalloc(dev, girq->num_parents,
    176					     sizeof(*girq->parents),
    177					     GFP_KERNEL);
    178		if (!girq->parents)
    179			return -ENOMEM;
    180
    181		girq->parents[0] = parent_irq;
    182		girq->default_type = IRQ_TYPE_NONE;
    183		girq->handler = handle_bad_irq;
    184	}
    185
    186	return devm_gpiochip_add_data(&pdev->dev, &ctrl->gc, ctrl);
    187}
    188
    189static const struct of_device_id idt_gpio_of_match[] = {
    190	{ .compatible = "idt,32434-gpio" },
    191	{ }
    192};
    193MODULE_DEVICE_TABLE(of, idt_gpio_of_match);
    194
    195static struct platform_driver idt_gpio_driver = {
    196	.probe = idt_gpio_probe,
    197	.driver = {
    198		.name = "idt3243x-gpio",
    199		.of_match_table = idt_gpio_of_match,
    200	},
    201};
    202module_platform_driver(idt_gpio_driver);
    203
    204MODULE_DESCRIPTION("IDT 79RC3243x GPIO/PIC Driver");
    205MODULE_AUTHOR("Thomas Bogendoerfer <tsbogend@alpha.franken.de>");
    206MODULE_LICENSE("GPL");