/*
* drm_irq.c IRQ and vblank support
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
*
* Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* 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 (including the next
* paragraph) 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
* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS 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.
*/
#include <drm/drmP.h>
//#include "drm_trace.h"
#include "drm_internal.h"
//#include <linux/interrupt.h> /* For task queue support */
#include <linux/slab.h>
#include <linux/vgaarb.h>
#include <linux/export.h>
/* Access macro for slots in vblank timestamp ringbuffer. */
#define vblanktimestamp(dev, crtc, count) \
((dev)->vblank[crtc].time[(count) % DRM_VBLANKTIME_RBSIZE])
/* Retry timestamp calculation up to 3 times to satisfy
* drm_timestamp_precision before giving up.
*/
#define DRM_TIMESTAMP_MAXRETRIES 3
/* Threshold in nanoseconds for detection of redundant
* vblank irq in drm_handle_vblank(). 1 msec should be ok.
*/
#define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000
static bool
drm_get_last_vbltimestamp(struct drm_device *dev, int crtc,
struct timeval *tvblank, unsigned flags);
static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */
/*
* Clear vblank timestamp buffer for a crtc.
*/
#if 0
/**
* drm_vblank_init - initialize vblank support
* @dev: drm_device
* @num_crtcs: number of crtcs supported by @dev
*
* This function initializes vblank support for @num_crtcs display pipelines.
*
* Returns:
* Zero on success or a negative error code on failure.
*/
int drm_vblank_init(struct drm_device *dev, int num_crtcs)
{
int i, ret = -ENOMEM;
spin_lock_init(&dev->vbl_lock);
spin_lock_init(&dev->vblank_time_lock);
dev->num_crtcs = num_crtcs;
dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL);
if (!dev->vblank)
goto err;
for (i = 0; i < num_crtcs; i++) {
struct drm_vblank_crtc *vblank = &dev->vblank[i];
vblank->dev = dev;
vblank->crtc = i;
init_waitqueue_head(&vblank->queue);
setup_timer(&vblank->disable_timer, vblank_disable_fn,
(unsigned long)vblank);
}
DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n");
/* Driver specific high-precision vblank timestamping supported? */
if (dev->driver->get_vblank_timestamp)
DRM_INFO("Driver supports precise vblank timestamp query.\n");
else
DRM_INFO("No driver support for vblank timestamp query.\n");
dev->vblank_disable_allowed = false;
return 0;
err:
dev->num_crtcs = 0;
return ret;
}
EXPORT_SYMBOL(drm_vblank_init);
#endif
irqreturn_t device_irq_handler(struct drm_device *dev)
{
// printf("video irq\n");
// printf("device %p driver %p handler %p\n", dev, dev->driver, dev->driver->irq_handler) ;
return dev->driver->irq_handler(0, dev);
}
/**
* drm_irq_install - install IRQ handler
* @dev: DRM device
* @irq: IRQ number to install the handler for
*
* Initializes the IRQ related data. Installs the handler, calling the driver
* irq_preinstall() and irq_postinstall() functions before and after the
* installation.
*
* This is the simplified helper interface provided for drivers with no special
* needs. Drivers which need to install interrupt handlers for multiple
* interrupts must instead set drm_device->irq_enabled to signal the DRM core
* that vblank interrupts are available.
*
* Returns:
* Zero on success or a negative error code on failure.
*/
int drm_irq_install(struct drm_device *dev, int irq)
{
int ret;
unsigned long sh_flags = 0;
if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
return -EINVAL;
if (irq == 0)
return -EINVAL;
/* Driver must have been initialized */
if (!dev->dev_private)
return -EINVAL;
if (dev->irq_enabled)
return -EBUSY;
dev->irq_enabled = true;
DRM_DEBUG("irq=%d\n", irq);
/* Before installing handler */
if (dev->driver->irq_preinstall)
dev->driver->irq_preinstall(dev);
ret = !AttachIntHandler(irq, device_irq_handler, (u32)dev);
/* After installing handler */
if (dev->driver->irq_postinstall)
ret = dev->driver->irq_postinstall(dev);
if (ret < 0) {
dev->irq_enabled = false;
DRM_ERROR(__FUNCTION__);
} else {
dev->irq = irq;
}
u16 cmd = PciRead16(dev->pdev->busnr, dev->pdev->devfn, 4);
cmd&= ~(1<<10);
PciWrite16(dev->pdev->busnr, dev->pdev->devfn, 4, cmd);
return ret;
}
EXPORT_SYMBOL(drm_irq_install);
u64 div64_u64(u64 dividend, u64 divisor)
{
u32 high, d;
high = divisor >> 32;
if (high) {
unsigned int shift = fls(high);
d = divisor >> shift;
dividend >>= shift;
} else
d = divisor;
return div_u64(dividend, d);
}
/**
* drm_calc_timestamping_constants - calculate vblank timestamp constants
* @crtc: drm_crtc whose timestamp constants should be updated.
* @mode: display mode containing the scanout timings
*
* Calculate and store various constants which are later
* needed by vblank and swap-completion timestamping, e.g,
* by drm_calc_vbltimestamp_from_scanoutpos(). They are
* derived from CRTC's true scanout timing, so they take
* things like panel scaling or other adjustments into account.
*/
void drm_calc_timestamping_constants(struct drm_crtc *crtc,
const struct drm_display_mode *mode)
{
int linedur_ns = 0, pixeldur_ns = 0, framedur_ns = 0;
int dotclock = mode->crtc_clock;
/* Valid dotclock? */
if (dotclock > 0) {
int frame_size = mode->crtc_htotal * mode->crtc_vtotal;
/*
* Convert scanline length in pixels and video
* dot clock to line duration, frame duration
* and pixel duration in nanoseconds:
*/
pixeldur_ns = 1000000 / dotclock;
linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000, dotclock);
framedur_ns = div_u64((u64) frame_size * 1000000, dotclock);
/*
* Fields of interlaced scanout modes are only half a frame duration.
*/
if (mode->flags & DRM_MODE_FLAG_INTERLACE)
framedur_ns /= 2;
} else
DRM_ERROR("crtc %d: Can't calculate constants, dotclock = 0!\n",
crtc->base.id);
crtc->pixeldur_ns = pixeldur_ns;
crtc->linedur_ns = linedur_ns;
crtc->framedur_ns = framedur_ns;
DRM_DEBUG("crtc %d: hwmode: htotal %d, vtotal %d, vdisplay %d\n",
crtc->base.id, mode->crtc_htotal,
mode->crtc_vtotal, mode->crtc_vdisplay);
DRM_DEBUG("crtc %d: clock %d kHz framedur %d linedur %d, pixeldur %d\n",
crtc->base.id, dotclock, framedur_ns,
linedur_ns, pixeldur_ns);
}
EXPORT_SYMBOL(drm_calc_timestamping_constants);
/**
* drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper
* @dev: DRM device
* @crtc: Which CRTC's vblank timestamp to retrieve
* @max_error: Desired maximum allowable error in timestamps (nanosecs)
* On return contains true maximum error of timestamp
* @vblank_time: Pointer to struct timeval which should receive the timestamp
* @flags: Flags to pass to driver:
* 0 = Default,
* DRM_CALLED_FROM_VBLIRQ = If function is called from vbl IRQ handler
* @refcrtc: CRTC which defines scanout timing
* @mode: mode which defines the scanout timings
*
* Implements calculation of exact vblank timestamps from given drm_display_mode
* timings and current video scanout position of a CRTC. This can be called from
* within get_vblank_timestamp() implementation of a kms driver to implement the
* actual timestamping.
*
* Should return timestamps conforming to the OML_sync_control OpenML
* extension specification. The timestamp corresponds to the end of
* the vblank interval, aka start of scanout of topmost-leftmost display
* pixel in the following video frame.
*
* Requires support for optional dev->driver->get_scanout_position()
* in kms driver, plus a bit of setup code to provide a drm_display_mode
* that corresponds to the true scanout timing.
*
* The current implementation only handles standard video modes. It
* returns as no operation if a doublescan or interlaced video mode is
* active. Higher level code is expected to handle this.
*
* Returns:
* Negative value on error, failure or if not supported in current
* video mode:
*
* -EINVAL - Invalid CRTC.
* -EAGAIN - Temporary unavailable, e.g., called before initial modeset.
* -ENOTSUPP - Function not supported in current display mode.
* -EIO - Failed, e.g., due to failed scanout position query.
*
* Returns or'ed positive status flags on success:
*
* DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
* DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
*
*/
int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, int crtc,
int *max_error,
struct timeval *vblank_time,
unsigned flags,
const struct drm_crtc *refcrtc,
const struct drm_display_mode *mode)
{
struct timeval tv_etime;
int vbl_status;
int vpos, hpos, i;
int framedur_ns, linedur_ns, pixeldur_ns, delta_ns, duration_ns;
bool invbl;
if (crtc < 0 || crtc >= dev->num_crtcs) {
DRM_ERROR("Invalid crtc %d\n", crtc);
return -EINVAL;
}
/* Scanout position query not supported? Should not happen. */
if (!dev->driver->get_scanout_position) {
DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
return -EIO;
}
/* Durations of frames, lines, pixels in nanoseconds. */
framedur_ns = refcrtc->framedur_ns;
linedur_ns = refcrtc->linedur_ns;
pixeldur_ns = refcrtc->pixeldur_ns;
/* If mode timing undefined, just return as no-op:
* Happens during initial modesetting of a crtc.
*/
if (framedur_ns == 0) {
DRM_DEBUG("crtc %d: Noop due to uninitialized mode.\n", crtc);
return -EAGAIN;
}
return -EIO;
}
EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
/**
* drm_vblank_get - get a reference count on vblank events
* @dev: DRM device
* @crtc: which CRTC to own
*
* Acquire a reference count on vblank events to avoid having them disabled
* while in use.
*
* This is the legacy version of drm_crtc_vblank_get().
*
* Returns:
* Zero on success, nonzero on failure.
*/
int drm_vblank_get(struct drm_device *dev, int crtc)
{
struct drm_vblank_crtc *vblank = &dev->vblank[crtc];
unsigned long irqflags;
int ret = 0;
#if 0
if (WARN_ON(crtc >= dev->num_crtcs))
return -EINVAL;
spin_lock_irqsave(&dev->vbl_lock, irqflags);
/* Going from 0->1 means we have to enable interrupts again */
if (atomic_add_return(1, &vblank->refcount) == 1) {
ret = drm_vblank_enable(dev, crtc);
} else {
if (!vblank->enabled) {
atomic_dec(&vblank->refcount);
ret = -EINVAL;
}
}
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
#endif
return ret;
}
EXPORT_SYMBOL(drm_vblank_get);
/**
* drm_crtc_vblank_get - get a reference count on vblank events
* @crtc: which CRTC to own
*
* Acquire a reference count on vblank events to avoid having them disabled
* while in use.
*
* This is the native kms version of drm_vblank_off().
*
* Returns:
* Zero on success, nonzero on failure.
*/
int drm_crtc_vblank_get(struct drm_crtc *crtc)
{
return drm_vblank_get(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_get);
/**
* drm_vblank_put - give up ownership of vblank events
* @dev: DRM device
* @crtc: which counter to give up
*
* Release ownership of a given vblank counter, turning off interrupts
* if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
*
* This is the legacy version of drm_crtc_vblank_put().
*/
void drm_vblank_put(struct drm_device *dev, int crtc)
{
#if 0
struct drm_vblank_crtc *vblank = &dev->vblank[crtc];
if (WARN_ON(atomic_read(&vblank->refcount) == 0))
return;
if (WARN_ON(crtc >= dev->num_crtcs))
return;
/* Last user schedules interrupt disable */
if (atomic_dec_and_test(&vblank->refcount)) {
if (drm_vblank_offdelay == 0)
return;
else if (dev->vblank_disable_immediate || drm_vblank_offdelay < 0)
vblank_disable_fn((unsigned long)vblank);
else
mod_timer(&vblank->disable_timer,
jiffies + ((drm_vblank_offdelay * HZ)/1000));
}
#endif
}
EXPORT_SYMBOL(drm_vblank_put);
/**
* drm_crtc_vblank_put - give up ownership of vblank events
* @crtc: which counter to give up
*
* Release ownership of a given vblank counter, turning off interrupts
* if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
*
* This is the native kms version of drm_vblank_put().
*/
void drm_crtc_vblank_put(struct drm_crtc *crtc)
{
drm_vblank_put(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_put);
/**
* drm_wait_one_vblank - wait for one vblank
* @dev: DRM device
* @crtc: crtc index
*
* This waits for one vblank to pass on @crtc, using the irq driver interfaces.
* It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
* due to lack of driver support or because the crtc is off.
*/
void drm_wait_one_vblank(struct drm_device *dev, int crtc)
{
#if 0
int ret;
u32 last;
ret = drm_vblank_get(dev, crtc);
if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", crtc, ret))
return;
last = drm_vblank_count(dev, crtc);
ret = wait_event_timeout(dev->vblank[crtc].queue,
last != drm_vblank_count(dev, crtc),
msecs_to_jiffies(100));
WARN(ret == 0, "vblank wait timed out on crtc %i\n", crtc);
drm_vblank_put(dev, crtc);
#endif
}
EXPORT_SYMBOL(drm_wait_one_vblank);
/**
* drm_crtc_wait_one_vblank - wait for one vblank
* @crtc: DRM crtc
*
* This waits for one vblank to pass on @crtc, using the irq driver interfaces.
* It is a failure to call this when the vblank irq for @crtc is disabled, e.g.
* due to lack of driver support or because the crtc is off.
*/
void drm_crtc_wait_one_vblank(struct drm_crtc *crtc)
{
drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_wait_one_vblank);
/**
* drm_vblank_off - disable vblank events on a CRTC
* @dev: DRM device
* @crtc: CRTC in question
*
* Drivers can use this function to shut down the vblank interrupt handling when
* disabling a crtc. This function ensures that the latest vblank frame count is
* stored so that drm_vblank_on() can restore it again.
*
* Drivers must use this function when the hardware vblank counter can get
* reset, e.g. when suspending.
*
* This is the legacy version of drm_crtc_vblank_off().
*/
void drm_vblank_off(struct drm_device *dev, int crtc)
{
struct drm_vblank_crtc *vblank = &dev->vblank[crtc];
struct drm_pending_vblank_event *e, *t;
struct timeval now;
unsigned long irqflags;
unsigned int seq;
}
EXPORT_SYMBOL(drm_vblank_off);
/**
* drm_crtc_vblank_off - disable vblank events on a CRTC
* @crtc: CRTC in question
*
* Drivers can use this function to shut down the vblank interrupt handling when
* disabling a crtc. This function ensures that the latest vblank frame count is
* stored so that drm_vblank_on can restore it again.
*
* Drivers must use this function when the hardware vblank counter can get
* reset, e.g. when suspending.
*
* This is the native kms version of drm_vblank_off().
*/
void drm_crtc_vblank_off(struct drm_crtc *crtc)
{
drm_vblank_off(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_off);
/**
* drm_vblank_on - enable vblank events on a CRTC
* @dev: DRM device
* @crtc: CRTC in question
*
* This functions restores the vblank interrupt state captured with
* drm_vblank_off() again. Note that calls to drm_vblank_on() and
* drm_vblank_off() can be unbalanced and so can also be unconditionally called
* in driver load code to reflect the current hardware state of the crtc.
*
* This is the legacy version of drm_crtc_vblank_on().
*/
void drm_vblank_on(struct drm_device *dev, int crtc)
{
struct drm_vblank_crtc *vblank = &dev->vblank[crtc];
unsigned long irqflags;
}
EXPORT_SYMBOL(drm_vblank_on);
/**
* drm_crtc_vblank_on - enable vblank events on a CRTC
* @crtc: CRTC in question
*
* This functions restores the vblank interrupt state captured with
* drm_vblank_off() again. Note that calls to drm_vblank_on() and
* drm_vblank_off() can be unbalanced and so can also be unconditionally called
* in driver load code to reflect the current hardware state of the crtc.
*
* This is the native kms version of drm_vblank_on().
*/
void drm_crtc_vblank_on(struct drm_crtc *crtc)
{
drm_vblank_on(crtc->dev, drm_crtc_index(crtc));
}
EXPORT_SYMBOL(drm_crtc_vblank_on);
/**
* drm_vblank_pre_modeset - account for vblanks across mode sets
* @dev: DRM device
* @crtc: CRTC in question
*
* Account for vblank events across mode setting events, which will likely
* reset the hardware frame counter.
*
* This is done by grabbing a temporary vblank reference to ensure that the
* vblank interrupt keeps running across the modeset sequence. With this the
* software-side vblank frame counting will ensure that there are no jumps or
* discontinuities.
*
* Unfortunately this approach is racy and also doesn't work when the vblank
* interrupt stops running, e.g. across system suspend resume. It is therefore
* highly recommended that drivers use the newer drm_vblank_off() and
* drm_vblank_on() instead. drm_vblank_pre_modeset() only works correctly when
* using "cooked" software vblank frame counters and not relying on any hardware
* counters.
*
* Drivers must call drm_vblank_post_modeset() when re-enabling the same crtc
* again.
*/
void drm_vblank_pre_modeset(struct drm_device *dev, int crtc)
{
#if 0
/* vblank is not initialized (IRQ not installed ?) */
if (!dev->num_crtcs)
return;
if (WARN_ON(crtc >= dev->num_crtcs))
return;
/*
* To avoid all the problems that might happen if interrupts
* were enabled/disabled around or between these calls, we just
* have the kernel take a reference on the CRTC (just once though
* to avoid corrupting the count if multiple, mismatch calls occur),
* so that interrupts remain enabled in the interim.
*/
if (!vblank->inmodeset) {
vblank->inmodeset = 0x1;
if (drm_vblank_get(dev, crtc) == 0)
vblank->inmodeset |= 0x2;
}
#endif
}
EXPORT_SYMBOL(drm_vblank_pre_modeset);
/**
* drm_vblank_post_modeset - undo drm_vblank_pre_modeset changes
* @dev: DRM device
* @crtc: CRTC in question
*
* This function again drops the temporary vblank reference acquired in
* drm_vblank_pre_modeset.
*/
void drm_vblank_post_modeset(struct drm_device *dev, int crtc)
{
#if 0
unsigned long irqflags;
/* vblank is not initialized (IRQ not installed ?), or has been freed */
if (!dev->num_crtcs)
return;
if (vblank->inmodeset) {
spin_lock_irqsave(&dev->vbl_lock, irqflags);
dev->vblank_disable_allowed = true;
spin_unlock_irqrestore(&dev->vbl_lock, irqflags);
if (vblank->inmodeset & 0x2)
drm_vblank_put(dev, crtc);
vblank->inmodeset = 0;
}
#endif
}
EXPORT_SYMBOL(drm_vblank_post_modeset);