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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msm_atomic.c (7127B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Copyright (C) 2014 Red Hat
      4 * Author: Rob Clark <robdclark@gmail.com>
      5 */
      6
      7#include <drm/drm_atomic_uapi.h>
      8#include <drm/drm_vblank.h>
      9
     10#include "msm_atomic_trace.h"
     11#include "msm_drv.h"
     12#include "msm_gem.h"
     13#include "msm_kms.h"
     14
     15/*
     16 * Helpers to control vblanks while we flush.. basically just to ensure
     17 * that vblank accounting is switched on, so we get valid seqn/timestamp
     18 * on pageflip events (if requested)
     19 */
     20
     21static void vblank_get(struct msm_kms *kms, unsigned crtc_mask)
     22{
     23	struct drm_crtc *crtc;
     24
     25	for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
     26		if (!crtc->state->active)
     27			continue;
     28		drm_crtc_vblank_get(crtc);
     29	}
     30}
     31
     32static void vblank_put(struct msm_kms *kms, unsigned crtc_mask)
     33{
     34	struct drm_crtc *crtc;
     35
     36	for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
     37		if (!crtc->state->active)
     38			continue;
     39		drm_crtc_vblank_put(crtc);
     40	}
     41}
     42
     43static void lock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
     44{
     45	int crtc_index;
     46	struct drm_crtc *crtc;
     47
     48	for_each_crtc_mask(kms->dev, crtc, crtc_mask) {
     49		crtc_index = drm_crtc_index(crtc);
     50		mutex_lock_nested(&kms->commit_lock[crtc_index], crtc_index);
     51	}
     52}
     53
     54static void unlock_crtcs(struct msm_kms *kms, unsigned int crtc_mask)
     55{
     56	struct drm_crtc *crtc;
     57
     58	for_each_crtc_mask_reverse(kms->dev, crtc, crtc_mask)
     59		mutex_unlock(&kms->commit_lock[drm_crtc_index(crtc)]);
     60}
     61
     62static void msm_atomic_async_commit(struct msm_kms *kms, int crtc_idx)
     63{
     64	unsigned crtc_mask = BIT(crtc_idx);
     65
     66	trace_msm_atomic_async_commit_start(crtc_mask);
     67
     68	lock_crtcs(kms, crtc_mask);
     69
     70	if (!(kms->pending_crtc_mask & crtc_mask)) {
     71		unlock_crtcs(kms, crtc_mask);
     72		goto out;
     73	}
     74
     75	kms->pending_crtc_mask &= ~crtc_mask;
     76
     77	kms->funcs->enable_commit(kms);
     78
     79	vblank_get(kms, crtc_mask);
     80
     81	/*
     82	 * Flush hardware updates:
     83	 */
     84	trace_msm_atomic_flush_commit(crtc_mask);
     85	kms->funcs->flush_commit(kms, crtc_mask);
     86
     87	/*
     88	 * Wait for flush to complete:
     89	 */
     90	trace_msm_atomic_wait_flush_start(crtc_mask);
     91	kms->funcs->wait_flush(kms, crtc_mask);
     92	trace_msm_atomic_wait_flush_finish(crtc_mask);
     93
     94	vblank_put(kms, crtc_mask);
     95
     96	kms->funcs->complete_commit(kms, crtc_mask);
     97	unlock_crtcs(kms, crtc_mask);
     98	kms->funcs->disable_commit(kms);
     99
    100out:
    101	trace_msm_atomic_async_commit_finish(crtc_mask);
    102}
    103
    104static void msm_atomic_pending_work(struct kthread_work *work)
    105{
    106	struct msm_pending_timer *timer = container_of(work,
    107			struct msm_pending_timer, work.work);
    108
    109	msm_atomic_async_commit(timer->kms, timer->crtc_idx);
    110}
    111
    112int msm_atomic_init_pending_timer(struct msm_pending_timer *timer,
    113		struct msm_kms *kms, int crtc_idx)
    114{
    115	timer->kms = kms;
    116	timer->crtc_idx = crtc_idx;
    117
    118	timer->worker = kthread_create_worker(0, "atomic-worker-%d", crtc_idx);
    119	if (IS_ERR(timer->worker)) {
    120		int ret = PTR_ERR(timer->worker);
    121		timer->worker = NULL;
    122		return ret;
    123	}
    124	sched_set_fifo(timer->worker->task);
    125
    126	msm_hrtimer_work_init(&timer->work, timer->worker,
    127			      msm_atomic_pending_work,
    128			      CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
    129
    130	return 0;
    131}
    132
    133void msm_atomic_destroy_pending_timer(struct msm_pending_timer *timer)
    134{
    135	if (timer->worker)
    136		kthread_destroy_worker(timer->worker);
    137}
    138
    139static bool can_do_async(struct drm_atomic_state *state,
    140		struct drm_crtc **async_crtc)
    141{
    142	struct drm_connector_state *connector_state;
    143	struct drm_connector *connector;
    144	struct drm_crtc_state *crtc_state;
    145	struct drm_crtc *crtc;
    146	int i, num_crtcs = 0;
    147
    148	if (!(state->legacy_cursor_update || state->async_update))
    149		return false;
    150
    151	/* any connector change, means slow path: */
    152	for_each_new_connector_in_state(state, connector, connector_state, i)
    153		return false;
    154
    155	for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
    156		if (drm_atomic_crtc_needs_modeset(crtc_state))
    157			return false;
    158		if (++num_crtcs > 1)
    159			return false;
    160		*async_crtc = crtc;
    161	}
    162
    163	return true;
    164}
    165
    166/* Get bitmask of crtcs that will need to be flushed.  The bitmask
    167 * can be used with for_each_crtc_mask() iterator, to iterate
    168 * effected crtcs without needing to preserve the atomic state.
    169 */
    170static unsigned get_crtc_mask(struct drm_atomic_state *state)
    171{
    172	struct drm_crtc_state *crtc_state;
    173	struct drm_crtc *crtc;
    174	unsigned i, mask = 0;
    175
    176	for_each_new_crtc_in_state(state, crtc, crtc_state, i)
    177		mask |= drm_crtc_mask(crtc);
    178
    179	return mask;
    180}
    181
    182void msm_atomic_commit_tail(struct drm_atomic_state *state)
    183{
    184	struct drm_device *dev = state->dev;
    185	struct msm_drm_private *priv = dev->dev_private;
    186	struct msm_kms *kms = priv->kms;
    187	struct drm_crtc *async_crtc = NULL;
    188	unsigned crtc_mask = get_crtc_mask(state);
    189	bool async = kms->funcs->vsync_time &&
    190			can_do_async(state, &async_crtc);
    191
    192	trace_msm_atomic_commit_tail_start(async, crtc_mask);
    193
    194	kms->funcs->enable_commit(kms);
    195
    196	/*
    197	 * Ensure any previous (potentially async) commit has
    198	 * completed:
    199	 */
    200	lock_crtcs(kms, crtc_mask);
    201	trace_msm_atomic_wait_flush_start(crtc_mask);
    202	kms->funcs->wait_flush(kms, crtc_mask);
    203	trace_msm_atomic_wait_flush_finish(crtc_mask);
    204
    205	/*
    206	 * Now that there is no in-progress flush, prepare the
    207	 * current update:
    208	 */
    209	kms->funcs->prepare_commit(kms, state);
    210
    211	/*
    212	 * Push atomic updates down to hardware:
    213	 */
    214	drm_atomic_helper_commit_modeset_disables(dev, state);
    215	drm_atomic_helper_commit_planes(dev, state, 0);
    216	drm_atomic_helper_commit_modeset_enables(dev, state);
    217
    218	if (async) {
    219		struct msm_pending_timer *timer =
    220			&kms->pending_timers[drm_crtc_index(async_crtc)];
    221
    222		/* async updates are limited to single-crtc updates: */
    223		WARN_ON(crtc_mask != drm_crtc_mask(async_crtc));
    224
    225		/*
    226		 * Start timer if we don't already have an update pending
    227		 * on this crtc:
    228		 */
    229		if (!(kms->pending_crtc_mask & crtc_mask)) {
    230			ktime_t vsync_time, wakeup_time;
    231
    232			kms->pending_crtc_mask |= crtc_mask;
    233
    234			vsync_time = kms->funcs->vsync_time(kms, async_crtc);
    235			wakeup_time = ktime_sub(vsync_time, ms_to_ktime(1));
    236
    237			msm_hrtimer_queue_work(&timer->work, wakeup_time,
    238					HRTIMER_MODE_ABS);
    239		}
    240
    241		kms->funcs->disable_commit(kms);
    242		unlock_crtcs(kms, crtc_mask);
    243		/*
    244		 * At this point, from drm core's perspective, we
    245		 * are done with the atomic update, so we can just
    246		 * go ahead and signal that it is done:
    247		 */
    248		drm_atomic_helper_commit_hw_done(state);
    249		drm_atomic_helper_cleanup_planes(dev, state);
    250
    251		trace_msm_atomic_commit_tail_finish(async, crtc_mask);
    252
    253		return;
    254	}
    255
    256	/*
    257	 * If there is any async flush pending on updated crtcs, fold
    258	 * them into the current flush.
    259	 */
    260	kms->pending_crtc_mask &= ~crtc_mask;
    261
    262	vblank_get(kms, crtc_mask);
    263
    264	/*
    265	 * Flush hardware updates:
    266	 */
    267	trace_msm_atomic_flush_commit(crtc_mask);
    268	kms->funcs->flush_commit(kms, crtc_mask);
    269	unlock_crtcs(kms, crtc_mask);
    270	/*
    271	 * Wait for flush to complete:
    272	 */
    273	trace_msm_atomic_wait_flush_start(crtc_mask);
    274	kms->funcs->wait_flush(kms, crtc_mask);
    275	trace_msm_atomic_wait_flush_finish(crtc_mask);
    276
    277	vblank_put(kms, crtc_mask);
    278
    279	lock_crtcs(kms, crtc_mask);
    280	kms->funcs->complete_commit(kms, crtc_mask);
    281	unlock_crtcs(kms, crtc_mask);
    282	kms->funcs->disable_commit(kms);
    283
    284	drm_atomic_helper_commit_hw_done(state);
    285	drm_atomic_helper_cleanup_planes(dev, state);
    286
    287	trace_msm_atomic_commit_tail_finish(async, crtc_mask);
    288}