blob: 67af2af70af091bf4b13ac03eb1078f867bc6cea [file] [log] [blame]
/*
* Copyright (C) 2015 Broadcom
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/**
* DOC: VC4 KMS
*
* This is the general code for implementing KMS mode setting that
* doesn't clearly associate with any of the other objects (plane,
* crtc, HDMI encoder).
*/
#include "drm_crtc.h"
#include "drm_atomic.h"
#include "drm_atomic_helper.h"
#include "drm_crtc_helper.h"
#include "drm_plane_helper.h"
#include "drm_fb_cma_helper.h"
#include "vc4_drv.h"
static void vc4_output_poll_changed(struct drm_device *dev)
{
struct vc4_dev *vc4 = to_vc4_dev(dev);
drm_fbdev_cma_hotplug_event(vc4->fbdev);
}
struct vc4_commit {
struct drm_device *dev;
struct drm_atomic_state *state;
struct vc4_seqno_cb cb;
};
static void
vc4_atomic_complete_commit(struct vc4_commit *c)
{
struct drm_atomic_state *state = c->state;
struct drm_device *dev = state->dev;
struct vc4_dev *vc4 = to_vc4_dev(dev);
drm_atomic_helper_commit_modeset_disables(dev, state);
drm_atomic_helper_commit_planes(dev, state, 0);
drm_atomic_helper_commit_modeset_enables(dev, state);
/* Make sure that drm_atomic_helper_wait_for_vblanks()
* actually waits for vblank. If we're doing a full atomic
* modeset (as opposed to a vc4_update_plane() short circuit),
* then we need to wait for scanout to be done with our
* display lists before we free it and potentially reallocate
* and overwrite the dlist memory with a new modeset.
*/
state->legacy_cursor_update = false;
drm_atomic_helper_wait_for_vblanks(dev, state);
drm_atomic_helper_cleanup_planes(dev, state);
drm_atomic_state_free(state);
up(&vc4->async_modeset);
kfree(c);
}
static void
vc4_atomic_complete_commit_seqno_cb(struct vc4_seqno_cb *cb)
{
struct vc4_commit *c = container_of(cb, struct vc4_commit, cb);
vc4_atomic_complete_commit(c);
}
static struct vc4_commit *commit_init(struct drm_atomic_state *state)
{
struct vc4_commit *c = kzalloc(sizeof(*c), GFP_KERNEL);
if (!c)
return NULL;
c->dev = state->dev;
c->state = state;
return c;
}
/**
* vc4_atomic_commit - commit validated state object
* @dev: DRM device
* @state: the driver state object
* @nonblock: nonblocking commit
*
* This function commits a with drm_atomic_helper_check() pre-validated state
* object. This can still fail when e.g. the framebuffer reservation fails. For
* now this doesn't implement asynchronous commits.
*
* RETURNS
* Zero for success or -errno.
*/
static int vc4_atomic_commit(struct drm_device *dev,
struct drm_atomic_state *state,
bool nonblock)
{
struct vc4_dev *vc4 = to_vc4_dev(dev);
int ret;
int i;
uint64_t wait_seqno = 0;
struct vc4_commit *c;
struct drm_plane *plane;
struct drm_plane_state *new_state;
c = commit_init(state);
if (!c)
return -ENOMEM;
/* Make sure that any outstanding modesets have finished. */
if (nonblock) {
struct drm_crtc *crtc;
struct drm_crtc_state *crtc_state;
unsigned long flags;
bool busy = false;
/*
* If there's an undispatched event to send then we're
* obviously still busy. If there isn't, then we can
* unconditionally wait for the semaphore because it
* shouldn't be contended (for long).
*
* This is to prevent a race where queuing a new flip
* from userspace immediately on receipt of an event
* beats our clean-up and returns EBUSY.
*/
spin_lock_irqsave(&dev->event_lock, flags);
for_each_crtc_in_state(state, crtc, crtc_state, i)
busy |= vc4_event_pending(crtc);
spin_unlock_irqrestore(&dev->event_lock, flags);
if (busy) {
kfree(c);
return -EBUSY;
}
}
ret = down_interruptible(&vc4->async_modeset);
if (ret) {
kfree(c);
return ret;
}
ret = drm_atomic_helper_prepare_planes(dev, state);
if (ret) {
kfree(c);
up(&vc4->async_modeset);
return ret;
}
for_each_plane_in_state(state, plane, new_state, i) {
if ((plane->state->fb != new_state->fb) && new_state->fb) {
struct drm_gem_cma_object *cma_bo =
drm_fb_cma_get_gem_obj(new_state->fb, 0);
struct vc4_bo *bo = to_vc4_bo(&cma_bo->base);
wait_seqno = max(bo->seqno, wait_seqno);
}
}
/*
* This is the point of no return - everything below never fails except
* when the hw goes bonghits. Which means we can commit the new state on
* the software side now.
*/
drm_atomic_helper_swap_state(state, true);
/*
* Everything below can be run asynchronously without the need to grab
* any modeset locks at all under one condition: It must be guaranteed
* that the asynchronous work has either been cancelled (if the driver
* supports it, which at least requires that the framebuffers get
* cleaned up with drm_atomic_helper_cleanup_planes()) or completed
* before the new state gets committed on the software side with
* drm_atomic_helper_swap_state().
*
* This scheme allows new atomic state updates to be prepared and
* checked in parallel to the asynchronous completion of the previous
* update. Which is important since compositors need to figure out the
* composition of the next frame right after having submitted the
* current layout.
*/
if (nonblock) {
vc4_queue_seqno_cb(dev, &c->cb, wait_seqno,
vc4_atomic_complete_commit_seqno_cb);
} else {
vc4_wait_for_seqno(dev, wait_seqno, ~0ull, false);
vc4_atomic_complete_commit(c);
}
return 0;
}
static const struct drm_mode_config_funcs vc4_mode_funcs = {
.output_poll_changed = vc4_output_poll_changed,
.atomic_check = drm_atomic_helper_check,
.atomic_commit = vc4_atomic_commit,
.fb_create = drm_fb_cma_create,
};
int vc4_kms_load(struct drm_device *dev)
{
struct vc4_dev *vc4 = to_vc4_dev(dev);
int ret;
sema_init(&vc4->async_modeset, 1);
ret = drm_vblank_init(dev, dev->mode_config.num_crtc);
if (ret < 0) {
dev_err(dev->dev, "failed to initialize vblank\n");
return ret;
}
dev->mode_config.max_width = 2048;
dev->mode_config.max_height = 2048;
dev->mode_config.funcs = &vc4_mode_funcs;
dev->mode_config.preferred_depth = 24;
dev->mode_config.async_page_flip = true;
drm_mode_config_reset(dev);
vc4->fbdev = drm_fbdev_cma_init(dev, 32,
dev->mode_config.num_crtc,
dev->mode_config.num_connector);
if (IS_ERR(vc4->fbdev))
vc4->fbdev = NULL;
drm_kms_helper_poll_init(dev);
return 0;
}