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Diffstat (limited to 'drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c')
-rw-r--r--drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c632
1 files changed, 632 insertions, 0 deletions
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c
new file mode 100644
index 000000000000..7e93a45948f7
--- /dev/null
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_vkms.c
@@ -0,0 +1,632 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/**************************************************************************
+ *
+ * Copyright (c) 2024 Broadcom. All Rights Reserved. The term
+ * “Broadcom” refers to Broadcom Inc. and/or its subsidiaries.
+ *
+ * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS 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 "vmwgfx_vkms.h"
+
+#include "vmwgfx_bo.h"
+#include "vmwgfx_drv.h"
+#include "vmwgfx_kms.h"
+#include "vmwgfx_vkms.h"
+
+#include "vmw_surface_cache.h"
+
+#include <drm/drm_crtc.h>
+#include <drm/drm_debugfs_crc.h>
+#include <drm/drm_print.h>
+#include <drm/drm_vblank.h>
+
+#include <linux/crc32.h>
+#include <linux/delay.h>
+
+#define GUESTINFO_VBLANK "guestinfo.vmwgfx.vkms_enable"
+
+static int
+vmw_surface_sync(struct vmw_private *vmw,
+ struct vmw_surface *surf)
+{
+ int ret;
+ struct vmw_fence_obj *fence = NULL;
+ struct vmw_bo *bo = surf->res.guest_memory_bo;
+
+ vmw_resource_clean(&surf->res);
+
+ ret = ttm_bo_reserve(&bo->tbo, false, false, NULL);
+ if (ret != 0) {
+ drm_warn(&vmw->drm, "%s: failed reserve\n", __func__);
+ goto done;
+ }
+
+ ret = vmw_execbuf_fence_commands(NULL, vmw, &fence, NULL);
+ if (ret != 0) {
+ drm_warn(&vmw->drm, "%s: failed execbuf\n", __func__);
+ ttm_bo_unreserve(&bo->tbo);
+ goto done;
+ }
+
+ dma_fence_wait(&fence->base, false);
+ dma_fence_put(&fence->base);
+
+ ttm_bo_unreserve(&bo->tbo);
+done:
+ return ret;
+}
+
+static int
+compute_crc(struct drm_crtc *crtc,
+ struct vmw_surface *surf,
+ u32 *crc)
+{
+ u8 *mapped_surface;
+ struct vmw_bo *bo = surf->res.guest_memory_bo;
+ const struct SVGA3dSurfaceDesc *desc =
+ vmw_surface_get_desc(surf->metadata.format);
+ u32 row_pitch_bytes;
+ SVGA3dSize blocks;
+ u32 y;
+
+ *crc = 0;
+
+ vmw_surface_get_size_in_blocks(desc, &surf->metadata.base_size, &blocks);
+ row_pitch_bytes = blocks.width * desc->pitchBytesPerBlock;
+ WARN_ON(!bo);
+ mapped_surface = vmw_bo_map_and_cache(bo);
+
+ for (y = 0; y < blocks.height; y++) {
+ *crc = crc32_le(*crc, mapped_surface, row_pitch_bytes);
+ mapped_surface += row_pitch_bytes;
+ }
+
+ vmw_bo_unmap(bo);
+
+ return 0;
+}
+
+static void
+crc_generate_worker(struct work_struct *work)
+{
+ struct vmw_display_unit *du =
+ container_of(work, struct vmw_display_unit, vkms.crc_generator_work);
+ struct drm_crtc *crtc = &du->crtc;
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+ bool crc_pending;
+ u64 frame_start, frame_end;
+ u32 crc32 = 0;
+ struct vmw_surface *surf = 0;
+ int ret;
+
+ spin_lock_irq(&du->vkms.crc_state_lock);
+ crc_pending = du->vkms.crc_pending;
+ spin_unlock_irq(&du->vkms.crc_state_lock);
+
+ /*
+ * We raced with the vblank hrtimer and previous work already computed
+ * the crc, nothing to do.
+ */
+ if (!crc_pending)
+ return;
+
+ spin_lock_irq(&du->vkms.crc_state_lock);
+ surf = du->vkms.surface;
+ spin_unlock_irq(&du->vkms.crc_state_lock);
+
+ if (vmw_surface_sync(vmw, surf)) {
+ drm_warn(crtc->dev, "CRC worker wasn't able to sync the crc surface!\n");
+ return;
+ }
+
+ ret = compute_crc(crtc, surf, &crc32);
+ if (ret)
+ return;
+
+ spin_lock_irq(&du->vkms.crc_state_lock);
+ frame_start = du->vkms.frame_start;
+ frame_end = du->vkms.frame_end;
+ crc_pending = du->vkms.crc_pending;
+ du->vkms.frame_start = 0;
+ du->vkms.frame_end = 0;
+ du->vkms.crc_pending = false;
+ spin_unlock_irq(&du->vkms.crc_state_lock);
+
+ /*
+ * The worker can fall behind the vblank hrtimer, make sure we catch up.
+ */
+ while (frame_start <= frame_end)
+ drm_crtc_add_crc_entry(crtc, true, frame_start++, &crc32);
+}
+
+static enum hrtimer_restart
+vmw_vkms_vblank_simulate(struct hrtimer *timer)
+{
+ struct vmw_display_unit *du = container_of(timer, struct vmw_display_unit, vkms.timer);
+ struct drm_crtc *crtc = &du->crtc;
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+ struct vmw_surface *surf = NULL;
+ u64 ret_overrun;
+ bool locked, ret;
+
+ ret_overrun = hrtimer_forward_now(&du->vkms.timer,
+ du->vkms.period_ns);
+ if (ret_overrun != 1)
+ drm_dbg_driver(crtc->dev, "vblank timer missed %lld frames.\n",
+ ret_overrun - 1);
+
+ locked = vmw_vkms_vblank_trylock(crtc);
+ ret = drm_crtc_handle_vblank(crtc);
+ WARN_ON(!ret);
+ if (!locked)
+ return HRTIMER_RESTART;
+ surf = du->vkms.surface;
+ vmw_vkms_unlock(crtc);
+
+ if (du->vkms.crc_enabled && surf) {
+ u64 frame = drm_crtc_accurate_vblank_count(crtc);
+
+ spin_lock(&du->vkms.crc_state_lock);
+ if (!du->vkms.crc_pending)
+ du->vkms.frame_start = frame;
+ else
+ drm_dbg_driver(crtc->dev,
+ "crc worker falling behind, frame_start: %llu, frame_end: %llu\n",
+ du->vkms.frame_start, frame);
+ du->vkms.frame_end = frame;
+ du->vkms.crc_pending = true;
+ spin_unlock(&du->vkms.crc_state_lock);
+
+ ret = queue_work(vmw->crc_workq, &du->vkms.crc_generator_work);
+ if (!ret)
+ drm_dbg_driver(crtc->dev, "Composer worker already queued\n");
+ }
+
+ return HRTIMER_RESTART;
+}
+
+void
+vmw_vkms_init(struct vmw_private *vmw)
+{
+ char buffer[64];
+ const size_t max_buf_len = sizeof(buffer) - 1;
+ size_t buf_len = max_buf_len;
+ int ret;
+
+ vmw->vkms_enabled = false;
+
+ ret = vmw_host_get_guestinfo(GUESTINFO_VBLANK, buffer, &buf_len);
+ if (ret || buf_len > max_buf_len)
+ return;
+ buffer[buf_len] = '\0';
+
+ ret = kstrtobool(buffer, &vmw->vkms_enabled);
+ if (!ret && vmw->vkms_enabled) {
+ ret = drm_vblank_init(&vmw->drm, VMWGFX_NUM_DISPLAY_UNITS);
+ vmw->vkms_enabled = (ret == 0);
+ }
+
+ vmw->crc_workq = alloc_ordered_workqueue("vmwgfx_crc_generator", 0);
+ if (!vmw->crc_workq) {
+ drm_warn(&vmw->drm, "crc workqueue allocation failed. Disabling vkms.");
+ vmw->vkms_enabled = false;
+ }
+ if (vmw->vkms_enabled)
+ drm_info(&vmw->drm, "VKMS enabled\n");
+}
+
+void
+vmw_vkms_cleanup(struct vmw_private *vmw)
+{
+ destroy_workqueue(vmw->crc_workq);
+}
+
+bool
+vmw_vkms_get_vblank_timestamp(struct drm_crtc *crtc,
+ int *max_error,
+ ktime_t *vblank_time,
+ bool in_vblank_irq)
+{
+ struct drm_device *dev = crtc->dev;
+ struct vmw_private *vmw = vmw_priv(dev);
+ unsigned int pipe = crtc->index;
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
+
+ if (!vmw->vkms_enabled)
+ return false;
+
+ if (!READ_ONCE(vblank->enabled)) {
+ *vblank_time = ktime_get();
+ return true;
+ }
+
+ *vblank_time = READ_ONCE(du->vkms.timer.node.expires);
+
+ if (WARN_ON(*vblank_time == vblank->time))
+ return true;
+
+ /*
+ * To prevent races we roll the hrtimer forward before we do any
+ * interrupt processing - this is how real hw works (the interrupt is
+ * only generated after all the vblank registers are updated) and what
+ * the vblank core expects. Therefore we need to always correct the
+ * timestampe by one frame.
+ */
+ *vblank_time -= du->vkms.period_ns;
+
+ return true;
+}
+
+int
+vmw_vkms_enable_vblank(struct drm_crtc *crtc)
+{
+ struct drm_device *dev = crtc->dev;
+ struct vmw_private *vmw = vmw_priv(dev);
+ unsigned int pipe = drm_crtc_index(crtc);
+ struct drm_vblank_crtc *vblank = &dev->vblank[pipe];
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+
+ if (!vmw->vkms_enabled)
+ return -EINVAL;
+
+ drm_calc_timestamping_constants(crtc, &crtc->mode);
+
+ hrtimer_init(&du->vkms.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ du->vkms.timer.function = &vmw_vkms_vblank_simulate;
+ du->vkms.period_ns = ktime_set(0, vblank->framedur_ns);
+ hrtimer_start(&du->vkms.timer, du->vkms.period_ns, HRTIMER_MODE_REL);
+
+ return 0;
+}
+
+void
+vmw_vkms_disable_vblank(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (!vmw->vkms_enabled)
+ return;
+
+ hrtimer_cancel(&du->vkms.timer);
+ du->vkms.surface = NULL;
+ du->vkms.period_ns = ktime_set(0, 0);
+}
+
+enum vmw_vkms_lock_state {
+ VMW_VKMS_LOCK_UNLOCKED = 0,
+ VMW_VKMS_LOCK_MODESET = 1,
+ VMW_VKMS_LOCK_VBLANK = 2
+};
+
+void
+vmw_vkms_crtc_init(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+
+ atomic_set(&du->vkms.atomic_lock, VMW_VKMS_LOCK_UNLOCKED);
+ spin_lock_init(&du->vkms.crc_state_lock);
+
+ INIT_WORK(&du->vkms.crc_generator_work, crc_generate_worker);
+ du->vkms.surface = NULL;
+}
+
+void
+vmw_vkms_crtc_cleanup(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+
+ WARN_ON(work_pending(&du->vkms.crc_generator_work));
+ hrtimer_cancel(&du->vkms.timer);
+}
+
+void
+vmw_vkms_crtc_atomic_begin(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (vmw->vkms_enabled)
+ vmw_vkms_modeset_lock(crtc);
+}
+
+void
+vmw_vkms_crtc_atomic_flush(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ unsigned long flags;
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (!vmw->vkms_enabled)
+ return;
+
+ if (crtc->state->event) {
+ spin_lock_irqsave(&crtc->dev->event_lock, flags);
+
+ if (drm_crtc_vblank_get(crtc) != 0)
+ drm_crtc_send_vblank_event(crtc, crtc->state->event);
+ else
+ drm_crtc_arm_vblank_event(crtc, crtc->state->event);
+
+ spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
+
+ crtc->state->event = NULL;
+ }
+
+ vmw_vkms_unlock(crtc);
+}
+
+void
+vmw_vkms_crtc_atomic_enable(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (vmw->vkms_enabled)
+ drm_crtc_vblank_on(crtc);
+}
+
+void
+vmw_vkms_crtc_atomic_disable(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (vmw->vkms_enabled)
+ drm_crtc_vblank_off(crtc);
+}
+
+static bool
+is_crc_supported(struct drm_crtc *crtc)
+{
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (!vmw->vkms_enabled)
+ return false;
+
+ if (vmw->active_display_unit != vmw_du_screen_target)
+ return false;
+
+ return true;
+}
+
+static const char * const pipe_crc_sources[] = {"auto"};
+
+static int
+crc_parse_source(const char *src_name,
+ bool *enabled)
+{
+ int ret = 0;
+
+ if (!src_name) {
+ *enabled = false;
+ } else if (strcmp(src_name, "auto") == 0) {
+ *enabled = true;
+ } else {
+ *enabled = false;
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+const char *const *
+vmw_vkms_get_crc_sources(struct drm_crtc *crtc,
+ size_t *count)
+{
+ *count = 0;
+ if (!is_crc_supported(crtc))
+ return NULL;
+
+ *count = ARRAY_SIZE(pipe_crc_sources);
+ return pipe_crc_sources;
+}
+
+int
+vmw_vkms_verify_crc_source(struct drm_crtc *crtc,
+ const char *src_name,
+ size_t *values_cnt)
+{
+ bool enabled;
+
+ if (!is_crc_supported(crtc))
+ return -EINVAL;
+
+ if (crc_parse_source(src_name, &enabled) < 0) {
+ drm_dbg_driver(crtc->dev, "unknown source '%s'\n", src_name);
+ return -EINVAL;
+ }
+
+ *values_cnt = 1;
+
+ return 0;
+}
+
+int
+vmw_vkms_set_crc_source(struct drm_crtc *crtc,
+ const char *src_name)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ bool enabled, prev_enabled, locked;
+ int ret;
+
+ if (!is_crc_supported(crtc))
+ return -EINVAL;
+
+ ret = crc_parse_source(src_name, &enabled);
+
+ if (enabled)
+ drm_crtc_vblank_get(crtc);
+
+ locked = vmw_vkms_modeset_lock_relaxed(crtc);
+ prev_enabled = du->vkms.crc_enabled;
+ du->vkms.crc_enabled = enabled;
+ if (locked)
+ vmw_vkms_unlock(crtc);
+
+ if (prev_enabled)
+ drm_crtc_vblank_put(crtc);
+
+ return ret;
+}
+
+void
+vmw_vkms_set_crc_surface(struct drm_crtc *crtc,
+ struct vmw_surface *surf)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ struct vmw_private *vmw = vmw_priv(crtc->dev);
+
+ if (vmw->vkms_enabled) {
+ WARN_ON(atomic_read(&du->vkms.atomic_lock) != VMW_VKMS_LOCK_MODESET);
+ du->vkms.surface = surf;
+ }
+}
+
+/**
+ * vmw_vkms_lock_max_wait_ns - Return the max wait for the vkms lock
+ * @du: The vmw_display_unit from which to grab the vblank timings
+ *
+ * Returns the maximum wait time used to acquire the vkms lock. By
+ * default uses a time of a single frame and in case where vblank
+ * was not initialized for the display unit 1/60th of a second.
+ */
+static inline u64
+vmw_vkms_lock_max_wait_ns(struct vmw_display_unit *du)
+{
+ s64 nsecs = ktime_to_ns(du->vkms.period_ns);
+
+ return (nsecs > 0) ? nsecs : 16666666;
+}
+
+/**
+ * vmw_vkms_modeset_lock - Protects access to crtc during modeset
+ * @crtc: The crtc to lock for vkms
+ *
+ * This function prevents the VKMS timers/callbacks from being called
+ * while a modeset operation is in process. We don't want the callbacks
+ * e.g. the vblank simulator to be trying to access incomplete state
+ * so we need to make sure they execute only when the modeset has
+ * finished.
+ *
+ * Normally this would have been done with a spinlock but locking the
+ * entire atomic modeset with vmwgfx is impossible because kms prepare
+ * executes non-atomic ops (e.g. vmw_validation_prepare holds a mutex to
+ * guard various bits of state). Which means that we need to synchronize
+ * atomic context (the vblank handler) with the non-atomic entirity
+ * of kms - so use an atomic_t to track which part of vkms has access
+ * to the basic vkms state.
+ */
+void
+vmw_vkms_modeset_lock(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ const u64 nsecs_delay = 10;
+ const u64 MAX_NSECS_DELAY = vmw_vkms_lock_max_wait_ns(du);
+ u64 total_delay = 0;
+ int ret;
+
+ do {
+ ret = atomic_cmpxchg(&du->vkms.atomic_lock,
+ VMW_VKMS_LOCK_UNLOCKED,
+ VMW_VKMS_LOCK_MODESET);
+ if (ret == VMW_VKMS_LOCK_UNLOCKED || total_delay >= MAX_NSECS_DELAY)
+ break;
+ ndelay(nsecs_delay);
+ total_delay += nsecs_delay;
+ } while (1);
+
+ if (total_delay >= MAX_NSECS_DELAY) {
+ drm_warn(crtc->dev, "VKMS lock expired! total_delay = %lld, ret = %d, cur = %d\n",
+ total_delay, ret, atomic_read(&du->vkms.atomic_lock));
+ }
+}
+
+/**
+ * vmw_vkms_modeset_lock_relaxed - Protects access to crtc during modeset
+ * @crtc: The crtc to lock for vkms
+ *
+ * Much like vmw_vkms_modeset_lock except that when the crtc is currently
+ * in a modeset it will return immediately.
+ *
+ * Returns true if actually locked vkms to modeset or false otherwise.
+ */
+bool
+vmw_vkms_modeset_lock_relaxed(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ const u64 nsecs_delay = 10;
+ const u64 MAX_NSECS_DELAY = vmw_vkms_lock_max_wait_ns(du);
+ u64 total_delay = 0;
+ int ret;
+
+ do {
+ ret = atomic_cmpxchg(&du->vkms.atomic_lock,
+ VMW_VKMS_LOCK_UNLOCKED,
+ VMW_VKMS_LOCK_MODESET);
+ if (ret == VMW_VKMS_LOCK_UNLOCKED ||
+ ret == VMW_VKMS_LOCK_MODESET ||
+ total_delay >= MAX_NSECS_DELAY)
+ break;
+ ndelay(nsecs_delay);
+ total_delay += nsecs_delay;
+ } while (1);
+
+ if (total_delay >= MAX_NSECS_DELAY) {
+ drm_warn(crtc->dev, "VKMS relaxed lock expired!\n");
+ return false;
+ }
+
+ return ret == VMW_VKMS_LOCK_UNLOCKED;
+}
+
+/**
+ * vmw_vkms_vblank_trylock - Protects access to crtc during vblank
+ * @crtc: The crtc to lock for vkms
+ *
+ * Tries to lock vkms for vblank, returns immediately.
+ *
+ * Returns true if locked vkms to vblank or false otherwise.
+ */
+bool
+vmw_vkms_vblank_trylock(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+ u32 ret;
+
+ ret = atomic_cmpxchg(&du->vkms.atomic_lock,
+ VMW_VKMS_LOCK_UNLOCKED,
+ VMW_VKMS_LOCK_VBLANK);
+
+ return ret == VMW_VKMS_LOCK_UNLOCKED;
+}
+
+void
+vmw_vkms_unlock(struct drm_crtc *crtc)
+{
+ struct vmw_display_unit *du = vmw_crtc_to_du(crtc);
+
+ /* Release flag; mark it as unlocked. */
+ atomic_set(&du->vkms.atomic_lock, VMW_VKMS_LOCK_UNLOCKED);
+}