Add a virtual hardware or vblank-less mode as a module to enable VKMS to emulate virtual hardware drivers. This means no vertical blanking events occur and pageflips are completed arbitrarily and when required for updating the frame.
Add a new drm_crtc_funcs struct, vkms_vblankless_crtc_funcs and a drm_crtc_helper_funcs struct, vkms_vblankless_crtc_helper_funcs() which hold the atomic helpers for virtual hardware mode. The existing vkms_crtc_funcs struct and vkms_crtc_helper_funcs struct hold atomic helpers for the default vblank mode. This makes the code flow clearer and testing virtual hardware mode easier.
Add a function vkms_crtc_composer() which calls the helper function, vkms_composer_common() for plane composition in vblank-less mode. vkms_crtc_composer() is directly called in the atomic hook in vkms_crtc_atomic_begin().
However, some crc captures still use vblanks which causes the crc-based igt tests to crash. So, no CRC functions are called in vblankless mode for now and will be implemented in a later patch.
This patchset has been tested with the igt tests- kms_writeback, kms_atomic , kms_lease, kms_flip, kms_pipe_get_crc and preserves results except for subtests related to crc reads and vertical blanking, in which case, tests are skipped.
The patch is based on Rodrigo Siqueira's patch(https://patchwork.freedesktop.org/patch/316851/?series=48469&rev=3) and the ensuing review.
Signed-off-by: Sumera Priyadarsini sylphrenadin@gmail.com --- Changes in V6: - Skip CRC functions in vblankless mode - Refactor helper function names(Melissa) Changes in V5: - Move vkms_crtc_composer() to this patch(Melissa) - Add more clarification for "vblank-less" mode(Pekka) - Replace kzalloc() with kvmalloc() in compose_active_planes() to fix memory allocation error for output frame - Fix checkpatch warnings (Melissa) Changes in V3: - Refactor patchset(Melissa) Changes in V2: - Add atomic helper functions in a separate struct for virtual hardware mode (Daniel) - Remove spinlock across 'vkms_output->lock' in vkms_crtc.c(Daniel) - Add vkms_composer_common() (Daniel) --- drivers/gpu/drm/vkms/vkms_composer.c | 21 +++++++++++-- drivers/gpu/drm/vkms/vkms_crtc.c | 43 +++++++++++++++++++++++++-- drivers/gpu/drm/vkms/vkms_drv.c | 16 +++++++--- drivers/gpu/drm/vkms/vkms_drv.h | 2 ++ drivers/gpu/drm/vkms/vkms_writeback.c | 3 +- 5 files changed, 74 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c index bca746fb5b53..a009589b2c3a 100644 --- a/drivers/gpu/drm/vkms/vkms_composer.c +++ b/drivers/gpu/drm/vkms/vkms_composer.c @@ -176,11 +176,12 @@ static int compose_active_planes(void **vaddr_out, { struct drm_framebuffer *fb = &primary_composer->fb; struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0); + const void *vaddr; int i;
if (!*vaddr_out) { - *vaddr_out = kzalloc(gem_obj->size, GFP_KERNEL); + *vaddr_out = kvmalloc(gem_obj->size, GFP_KERNEL); if (!*vaddr_out) { DRM_ERROR("Cannot allocate memory for output frame."); return -ENOMEM; @@ -229,7 +230,7 @@ int vkms_composer_common(struct vkms_crtc_state *crtc_state,
if (ret) { if ((ret == -EINVAL || ret == -ENOMEM) && !wb_pending) - kfree(vaddr_out); + kvfree(vaddr_out); return ret; }
@@ -241,7 +242,7 @@ int vkms_composer_common(struct vkms_crtc_state *crtc_state, crtc_state->wb_pending = false; spin_unlock_irq(&out->composer_lock); } else { - kfree(vaddr_out); + kvfree(vaddr_out); }
return 0; @@ -296,6 +297,20 @@ void vkms_composer_worker(struct work_struct *work) drm_crtc_add_crc_entry(crtc, true, frame_start++, &crc32); }
+void vkms_crtc_composer(struct vkms_crtc_state *crtc_state) +{ + struct drm_crtc *crtc = crtc_state->base.crtc; + struct vkms_output *out = drm_crtc_to_vkms_output(crtc); + u32 crc32 = 0; + int ret; + + ret = vkms_composer_common(crtc_state, out, crtc_state->wb_pending, &crc32); + if (ret == -EINVAL) + return; + + drm_crtc_add_crc_entry(crtc, true, 0, &crc32); +} + static const char * const pipe_crc_sources[] = {"auto"};
const char *const *vkms_get_crc_sources(struct drm_crtc *crtc, diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c index 57bbd32e9beb..4a933553e0e4 100644 --- a/drivers/gpu/drm/vkms/vkms_crtc.c +++ b/drivers/gpu/drm/vkms/vkms_crtc.c @@ -174,6 +174,15 @@ static const struct drm_crtc_funcs vkms_crtc_funcs = { .verify_crc_source = vkms_verify_crc_source, };
+static const struct drm_crtc_funcs vkms_vblankless_crtc_funcs = { + .set_config = drm_atomic_helper_set_config, + .destroy = drm_crtc_cleanup, + .page_flip = drm_atomic_helper_page_flip, + .reset = vkms_atomic_crtc_reset, + .atomic_duplicate_state = vkms_atomic_crtc_duplicate_state, + .atomic_destroy_state = vkms_atomic_crtc_destroy_state, +}; + static int vkms_crtc_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state) { @@ -268,6 +277,20 @@ static void vkms_crtc_atomic_flush(struct drm_crtc *crtc, spin_unlock_irq(&vkms_output->lock); }
+/* + * Crtc functions for virtual hardware/vblankless mode + */ +static void vkms_vblankless_crtc_atomic_flush(struct drm_crtc *crtc, + struct drm_atomic_state *state) +{ + struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc); + struct vkms_crtc_state *vkms_state = to_vkms_crtc_state(crtc->state); + + vkms_crtc_composer(vkms_state); + + vkms_output->composer_state = to_vkms_crtc_state(crtc->state); +} + static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = { .atomic_check = vkms_crtc_atomic_check, .atomic_begin = vkms_crtc_atomic_begin, @@ -276,20 +299,34 @@ static const struct drm_crtc_helper_funcs vkms_crtc_helper_funcs = { .atomic_disable = vkms_crtc_atomic_disable, };
+static const struct drm_crtc_helper_funcs vkms_vblankless_crtc_helper_funcs = { + .atomic_check = vkms_crtc_atomic_check, + .atomic_flush = vkms_vblankless_crtc_atomic_flush, +}; + int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc, struct drm_plane *primary, struct drm_plane *cursor) { struct vkms_output *vkms_out = drm_crtc_to_vkms_output(crtc); + struct vkms_device *vkmsdev = drm_device_to_vkms_device(dev); int ret;
- ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor, - &vkms_crtc_funcs, NULL); + if (vkmsdev->config->virtual_hw) + ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor, + &vkms_vblankless_crtc_funcs, NULL); + else + ret = drm_crtc_init_with_planes(dev, crtc, primary, cursor, + &vkms_crtc_funcs, NULL); + if (ret) { DRM_ERROR("Failed to init CRTC\n"); return ret; }
- drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs); + if (vkmsdev->config->virtual_hw) + drm_crtc_helper_add(crtc, &vkms_vblankless_crtc_helper_funcs); + else + drm_crtc_helper_add(crtc, &vkms_crtc_helper_funcs);
spin_lock_init(&vkms_out->lock); spin_lock_init(&vkms_out->composer_lock); diff --git a/drivers/gpu/drm/vkms/vkms_drv.c b/drivers/gpu/drm/vkms/vkms_drv.c index 0ffe5f0e33f7..ee78f5eef653 100644 --- a/drivers/gpu/drm/vkms/vkms_drv.c +++ b/drivers/gpu/drm/vkms/vkms_drv.c @@ -51,6 +51,10 @@ static bool enable_overlay; module_param_named(enable_overlay, enable_overlay, bool, 0444); MODULE_PARM_DESC(enable_overlay, "Enable/Disable overlay support");
+static bool enable_virtual_hw; +module_param_named(enable_virtual_hw, enable_virtual_hw, bool, 0444); +MODULE_PARM_DESC(enable_virtual_hw, "Enable/Disable virtual hardware mode(vblank-less mode)"); + DEFINE_DRM_GEM_FOPS(vkms_driver_fops);
static void vkms_release(struct drm_device *dev) @@ -98,6 +102,7 @@ static int vkms_config_show(struct seq_file *m, void *data) seq_printf(m, "writeback=%d\n", vkmsdev->config->writeback); seq_printf(m, "cursor=%d\n", vkmsdev->config->cursor); seq_printf(m, "overlay=%d\n", vkmsdev->config->overlay); + seq_printf(m, "virtual_hw=%d\n", vkmsdev->config->virtual_hw);
return 0; } @@ -191,10 +196,12 @@ static int vkms_create(struct vkms_config *config) goto out_devres; }
- ret = drm_vblank_init(&vkms_device->drm, 1); - if (ret) { - DRM_ERROR("Failed to vblank\n"); - goto out_devres; + if (!vkms_device->config->virtual_hw) { + ret = drm_vblank_init(&vkms_device->drm, 1); + if (ret) { + DRM_ERROR("Failed to vblank\n"); + goto out_devres; + } }
ret = vkms_modeset_init(vkms_device); @@ -229,6 +236,7 @@ static int __init vkms_init(void) config->cursor = enable_cursor; config->writeback = enable_writeback; config->overlay = enable_overlay; + config->virtual_hw = enable_virtual_hw;
return vkms_create(config); } diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h index 6f5f63591c20..d64554f21838 100644 --- a/drivers/gpu/drm/vkms/vkms_drv.h +++ b/drivers/gpu/drm/vkms/vkms_drv.h @@ -97,6 +97,7 @@ struct vkms_config { bool writeback; bool cursor; bool overlay; + bool virtual_hw; /* only set when instantiated */ struct vkms_device *dev; }; @@ -141,6 +142,7 @@ int vkms_composer_common(struct vkms_crtc_state *crtc_state, struct vkms_output bool wb_pending, uint32_t *crcs); void vkms_composer_worker(struct work_struct *work); void vkms_set_composer(struct vkms_output *out, bool enabled); +void vkms_crtc_composer(struct vkms_crtc_state *crtc_state);
/* Writeback */ int vkms_enable_writeback_connector(struct vkms_device *vkmsdev); diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c index 8694227f555f..6082cacbca1e 100644 --- a/drivers/gpu/drm/vkms/vkms_writeback.c +++ b/drivers/gpu/drm/vkms/vkms_writeback.c @@ -120,7 +120,8 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn, if (!conn_state) return;
- vkms_set_composer(&vkmsdev->output, true); + if (!vkmsdev->config->virtual_hw) + vkms_set_composer(&vkmsdev->output, true);
spin_lock_irq(&output->composer_lock); crtc_state->active_writeback = conn_state->writeback_job->priv;