linux/drivers/gpu/drm/nouveau/nv50_gpio.c
Ben Skeggs fce2bad0ee drm/nv50: rework PGPIO IRQ handling and hotplug detection
Allows callers to install their own handlers for when a GPIO line
changes state (such as for hotplug detect).

This also fixes a bug where we weren't acknowledging the GPIO IRQ
until after the bottom half had run, causing a severe IRQ storm
in some cases.

Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
2010-12-03 15:11:45 +10:00

300 lines
7.3 KiB
C

/*
* Copyright 2010 Red Hat Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Ben Skeggs
*/
#include "drmP.h"
#include "nouveau_drv.h"
#include "nouveau_hw.h"
#include "nv50_display.h"
static void nv50_gpio_isr(struct drm_device *dev);
static void nv50_gpio_isr_bh(struct work_struct *work);
struct nv50_gpio_priv {
struct list_head handlers;
spinlock_t lock;
};
struct nv50_gpio_handler {
struct drm_device *dev;
struct list_head head;
struct work_struct work;
bool inhibit;
struct dcb_gpio_entry *gpio;
void (*handler)(void *data, int state);
void *data;
};
static int
nv50_gpio_location(struct dcb_gpio_entry *gpio, uint32_t *reg, uint32_t *shift)
{
const uint32_t nv50_gpio_reg[4] = { 0xe104, 0xe108, 0xe280, 0xe284 };
if (gpio->line >= 32)
return -EINVAL;
*reg = nv50_gpio_reg[gpio->line >> 3];
*shift = (gpio->line & 7) << 2;
return 0;
}
int
nv50_gpio_get(struct drm_device *dev, enum dcb_gpio_tag tag)
{
struct dcb_gpio_entry *gpio;
uint32_t r, s, v;
gpio = nouveau_bios_gpio_entry(dev, tag);
if (!gpio)
return -ENOENT;
if (nv50_gpio_location(gpio, &r, &s))
return -EINVAL;
v = nv_rd32(dev, r) >> (s + 2);
return ((v & 1) == (gpio->state[1] & 1));
}
int
nv50_gpio_set(struct drm_device *dev, enum dcb_gpio_tag tag, int state)
{
struct dcb_gpio_entry *gpio;
uint32_t r, s, v;
gpio = nouveau_bios_gpio_entry(dev, tag);
if (!gpio)
return -ENOENT;
if (nv50_gpio_location(gpio, &r, &s))
return -EINVAL;
v = nv_rd32(dev, r) & ~(0x3 << s);
v |= (gpio->state[state] ^ 2) << s;
nv_wr32(dev, r, v);
return 0;
}
int
nv50_gpio_irq_register(struct drm_device *dev, enum dcb_gpio_tag tag,
void (*handler)(void *, int), void *data)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
struct nv50_gpio_priv *priv = pgpio->priv;
struct nv50_gpio_handler *gpioh;
struct dcb_gpio_entry *gpio;
unsigned long flags;
gpio = nouveau_bios_gpio_entry(dev, tag);
if (!gpio)
return -ENOENT;
gpioh = kzalloc(sizeof(*gpioh), GFP_KERNEL);
if (!gpioh)
return -ENOMEM;
INIT_WORK(&gpioh->work, nv50_gpio_isr_bh);
gpioh->dev = dev;
gpioh->gpio = gpio;
gpioh->handler = handler;
gpioh->data = data;
spin_lock_irqsave(&priv->lock, flags);
list_add(&gpioh->head, &priv->handlers);
spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
void
nv50_gpio_irq_unregister(struct drm_device *dev, enum dcb_gpio_tag tag,
void (*handler)(void *, int), void *data)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
struct nv50_gpio_priv *priv = pgpio->priv;
struct nv50_gpio_handler *gpioh, *tmp;
struct dcb_gpio_entry *gpio;
unsigned long flags;
gpio = nouveau_bios_gpio_entry(dev, tag);
if (!gpio)
return;
spin_lock_irqsave(&priv->lock, flags);
list_for_each_entry_safe(gpioh, tmp, &priv->handlers, head) {
if (gpioh->gpio != gpio ||
gpioh->handler != handler ||
gpioh->data != data)
continue;
list_del(&gpioh->head);
kfree(gpioh);
}
spin_unlock_irqrestore(&priv->lock, flags);
}
bool
nv50_gpio_irq_enable(struct drm_device *dev, enum dcb_gpio_tag tag, bool on)
{
struct dcb_gpio_entry *gpio;
u32 reg, mask;
gpio = nouveau_bios_gpio_entry(dev, tag);
if (!gpio)
return false;
reg = gpio->line < 16 ? 0xe050 : 0xe070;
mask = 0x00010001 << (gpio->line & 0xf);
nv_wr32(dev, reg + 4, mask);
reg = nv_mask(dev, reg + 0, mask, on ? mask : 0);
return (reg & mask) == mask;
}
static int
nv50_gpio_create(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
struct nv50_gpio_priv *priv;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
INIT_LIST_HEAD(&priv->handlers);
spin_lock_init(&priv->lock);
pgpio->priv = priv;
return 0;
}
static void
nv50_gpio_destroy(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
kfree(pgpio->priv);
pgpio->priv = NULL;
}
int
nv50_gpio_init(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
struct nv50_gpio_priv *priv;
int ret;
if (!pgpio->priv) {
ret = nv50_gpio_create(dev);
if (ret)
return ret;
}
priv = pgpio->priv;
/* disable, and ack any pending gpio interrupts */
nv_wr32(dev, 0xe050, 0x00000000);
nv_wr32(dev, 0xe054, 0xffffffff);
if (dev_priv->chipset >= 0x90) {
nv_wr32(dev, 0xe070, 0x00000000);
nv_wr32(dev, 0xe074, 0xffffffff);
}
nouveau_irq_register(dev, 21, nv50_gpio_isr);
return 0;
}
void
nv50_gpio_fini(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
nv_wr32(dev, 0xe050, 0x00000000);
if (dev_priv->chipset >= 0x90)
nv_wr32(dev, 0xe070, 0x00000000);
nouveau_irq_unregister(dev, 21);
nv50_gpio_destroy(dev);
}
static void
nv50_gpio_isr_bh(struct work_struct *work)
{
struct nv50_gpio_handler *gpioh =
container_of(work, struct nv50_gpio_handler, work);
struct drm_nouveau_private *dev_priv = gpioh->dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
struct nv50_gpio_priv *priv = pgpio->priv;
unsigned long flags;
int state;
state = pgpio->get(gpioh->dev, gpioh->gpio->tag);
if (state < 0)
return;
gpioh->handler(gpioh->data, state);
spin_lock_irqsave(&priv->lock, flags);
gpioh->inhibit = false;
spin_unlock_irqrestore(&priv->lock, flags);
}
static void
nv50_gpio_isr(struct drm_device *dev)
{
struct drm_nouveau_private *dev_priv = dev->dev_private;
struct nouveau_gpio_engine *pgpio = &dev_priv->engine.gpio;
struct nv50_gpio_priv *priv = pgpio->priv;
struct nv50_gpio_handler *gpioh;
u32 intr0, intr1 = 0;
u32 hi, lo, ch;
intr0 = nv_rd32(dev, 0xe054) & nv_rd32(dev, 0xe050);
if (dev_priv->chipset >= 0x90)
intr1 = nv_rd32(dev, 0xe074) & nv_rd32(dev, 0xe070);
hi = (intr0 & 0x0000ffff) | (intr1 << 16);
lo = (intr0 >> 16) | (intr1 & 0xffff0000);
ch = hi | lo;
nv_wr32(dev, 0xe054, intr0);
if (dev_priv->chipset >= 0x90)
nv_wr32(dev, 0xe074, intr1);
spin_lock(&priv->lock);
list_for_each_entry(gpioh, &priv->handlers, head) {
if (!(ch & (1 << gpioh->gpio->line)))
continue;
if (gpioh->inhibit)
continue;
gpioh->inhibit = true;
queue_work(dev_priv->wq, &gpioh->work);
}
spin_unlock(&priv->lock);
}