[v3] drm/msm/disp/dpu1: turn off vblank irqs aggressively in dpu
Kalyan Thota
kalyant at codeaurora.org
Fri Feb 12 11:44:49 UTC 2021
Set the flag vblank_disable_immediate = true to turn off vblank irqs
immediately as soon as drm_vblank_put is requested so that there are
no irqs triggered during idle state. This will reduce cpu wakeups
and help in power saving.
To enable vblank_disable_immediate flag the underlying KMS driver
needs to support high precision vblank timestamping and also a
reliable way of providing vblank counter which is incrementing
at the leading edge of vblank.
This patch also brings in changes to support vblank_disable_immediate
requirement in dpu driver.
Changes in v1:
- Specify reason to add vblank timestamp support. (Rob)
- Add changes to provide vblank counter from dpu driver.
Changes in v2:
- fix warn stack reported by Rob with v2 patch
Signed-off-by: Kalyan Thota <kalyant at codeaurora.org>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 80 +++++++++++++++++++++++++++++
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 28 +++++++++-
drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h | 11 ++++
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 5 ++
4 files changed, 123 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index d4662e8..9a80981 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -65,6 +65,83 @@ static void dpu_crtc_destroy(struct drm_crtc *crtc)
kfree(dpu_crtc);
}
+static struct drm_encoder *get_encoder_from_crtc(struct drm_crtc *crtc)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_encoder *encoder;
+
+ drm_for_each_encoder(encoder, dev)
+ if (encoder->crtc == crtc)
+ return encoder;
+
+ return NULL;
+}
+
+static u32 dpu_crtc_get_vblank_counter(struct drm_crtc *crtc)
+{
+ struct drm_encoder *encoder;
+
+ encoder = get_encoder_from_crtc(crtc);
+ if (!encoder) {
+ DRM_ERROR("no encoder found for crtc %d\n", crtc->index);
+ return false;
+ }
+
+ return dpu_encoder_get_frame_count(encoder);
+}
+
+static bool dpu_crtc_get_scanout_position(struct drm_crtc *crtc,
+ bool in_vblank_irq,
+ int *vpos, int *hpos,
+ ktime_t *stime, ktime_t *etime,
+ const struct drm_display_mode *mode)
+{
+ unsigned int pipe = crtc->index;
+ struct drm_encoder *encoder;
+ int line, vsw, vbp, vactive_start, vactive_end, vfp_end;
+
+ encoder = get_encoder_from_crtc(crtc);
+ if (!encoder) {
+ DRM_ERROR("no encoder found for crtc %d\n", pipe);
+ return false;
+ }
+
+ vsw = mode->crtc_vsync_end - mode->crtc_vsync_start;
+ vbp = mode->crtc_vtotal - mode->crtc_vsync_end;
+
+ /*
+ * the line counter is 1 at the start of the VSYNC pulse and VTOTAL at
+ * the end of VFP. Translate the porch values relative to the line
+ * counter positions.
+ */
+
+ vactive_start = vsw + vbp + 1;
+ vactive_end = vactive_start + mode->crtc_vdisplay;
+
+ /* last scan line before VSYNC */
+ vfp_end = mode->crtc_vtotal;
+
+ if (stime)
+ *stime = ktime_get();
+
+ line = dpu_encoder_get_linecount(encoder);
+
+ if (line < vactive_start)
+ line -= vactive_start;
+ else if (line > vactive_end)
+ line = line - vfp_end - vactive_start;
+ else
+ line -= vactive_start;
+
+ *vpos = line;
+ *hpos = 0;
+
+ if (etime)
+ *etime = ktime_get();
+
+ return true;
+}
+
static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer,
struct dpu_plane_state *pstate, struct dpu_format *format)
{
@@ -1243,6 +1320,8 @@ static const struct drm_crtc_funcs dpu_crtc_funcs = {
.early_unregister = dpu_crtc_early_unregister,
.enable_vblank = msm_crtc_enable_vblank,
.disable_vblank = msm_crtc_disable_vblank,
+ .get_vblank_timestamp = drm_crtc_vblank_helper_get_vblank_timestamp,
+ .get_vblank_counter = dpu_crtc_get_vblank_counter,
};
static const struct drm_crtc_helper_funcs dpu_crtc_helper_funcs = {
@@ -1251,6 +1330,7 @@ static const struct drm_crtc_helper_funcs dpu_crtc_helper_funcs = {
.atomic_check = dpu_crtc_atomic_check,
.atomic_begin = dpu_crtc_atomic_begin,
.atomic_flush = dpu_crtc_atomic_flush,
+ .get_scanout_position = dpu_crtc_get_scanout_position,
};
/* initialize crtc */
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
index f7f5c25..fb6546c 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
@@ -425,6 +425,32 @@ int dpu_encoder_helper_unregister_irq(struct dpu_encoder_phys *phys_enc,
return 0;
}
+int dpu_encoder_get_frame_count(struct drm_encoder *drm_enc)
+{
+ struct dpu_encoder_virt *dpu_enc;
+ struct dpu_encoder_phys *phy_enc;
+
+ dpu_enc = to_dpu_encoder_virt(drm_enc);
+ phy_enc = dpu_enc ? dpu_enc->cur_master : NULL;
+
+ return phy_enc ? atomic_read(&phy_enc->vsync_cnt) : 0;
+}
+
+int dpu_encoder_get_linecount(struct drm_encoder *drm_enc)
+{
+ struct dpu_encoder_virt *dpu_enc;
+ struct dpu_encoder_phys *phys;
+ int linecount = 0;
+
+ dpu_enc = to_dpu_encoder_virt(drm_enc);
+ phys = dpu_enc ? dpu_enc->cur_master : NULL;
+
+ if (phys && phys->ops.get_line_count)
+ linecount = phys->ops.get_line_count(phys);
+
+ return linecount;
+}
+
void dpu_encoder_get_hw_resources(struct drm_encoder *drm_enc,
struct dpu_encoder_hw_resources *hw_res)
{
@@ -1296,12 +1322,12 @@ static void dpu_encoder_vblank_callback(struct drm_encoder *drm_enc,
DPU_ATRACE_BEGIN("encoder_vblank_callback");
dpu_enc = to_dpu_encoder_virt(drm_enc);
+ atomic_inc(&phy_enc->vsync_cnt);
spin_lock_irqsave(&dpu_enc->enc_spinlock, lock_flags);
if (dpu_enc->crtc)
dpu_crtc_vblank_callback(dpu_enc->crtc);
spin_unlock_irqrestore(&dpu_enc->enc_spinlock, lock_flags);
- atomic_inc(&phy_enc->vsync_cnt);
DPU_ATRACE_END("encoder_vblank_callback");
}
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
index b491346..99a5d73 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h
@@ -156,5 +156,16 @@ void dpu_encoder_prepare_commit(struct drm_encoder *drm_enc);
*/
void dpu_encoder_set_idle_timeout(struct drm_encoder *drm_enc,
u32 idle_timeout);
+/**
+ * dpu_encoder_get_linecount - get interface line count for the encoder.
+ * @drm_enc: Pointer to previously created drm encoder structure
+ */
+int dpu_encoder_get_linecount(struct drm_encoder *drm_enc);
+
+/**
+ * dpu_encoder_get_frame_count - get interface frame count for the encoder.
+ * @drm_enc: Pointer to previously created drm encoder structure
+ */
+int dpu_encoder_get_frame_count(struct drm_encoder *drm_enc);
#endif /* __DPU_ENCODER_H__ */
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index 374b0e8..ed636f1 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -14,6 +14,7 @@
#include <drm/drm_crtc.h>
#include <drm/drm_file.h>
+#include <drm/drm_vblank.h>
#include "msm_drv.h"
#include "msm_mmu.h"
@@ -1020,6 +1021,10 @@ static int dpu_kms_hw_init(struct msm_kms *kms)
*/
dev->mode_config.allow_fb_modifiers = true;
+ dev->max_vblank_count = 0xffffffff;
+ /* Disable vblank irqs aggressively for power-saving */
+ dev->vblank_disable_immediate = true;
+
/*
* _dpu_kms_drm_obj_init should create the DRM related objects
* i.e. CRTCs, planes, encoders, connectors and so forth
--
2.7.4
More information about the dri-devel
mailing list