On 2021-07-02 02:20, Dmitry Baryshkov wrote:
On 02/07/2021 00:12, abhinavk@xxxxxxxxxxxxxx wrote:
On 2021-06-09 14:17, Dmitry Baryshkov wrote:
Move setting up encoders from set_encoder_mode to
_dpu_kms_initialize_dsi() / _dpu_kms_initialize_displayport(). This
allows us to support not only "single DSI" and "dual DSI" but also
"two
independent DSI" configurations. In future this would also help
adding
support for multiple DP connectors.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
I will have to see Bjorn's changes to check why it was dependent on
this cleanup.
Is the plan to call _dpu_kms_initialize_displayport() twice?
Yes. He needs to initialize several displayport interfaces. With the
current code he has to map ids in the set_encoder_mode, using encoder
ids (to fill up the info.h_tile_instance, which is hardcoded to 0 for
DP in the current code).
But still I am not able to put together where is the dependency on
that series
with this one. Can you please elaborate on that a little bit?
It is possible to support independent outputs with the current code. I
did that for DSI, Bjorn did for DP. However it results in quite an
ugly code to map received encoder in set_encoder_mode back to the DSI
(DP) instances to fill the h_tiles. If we drop the whole
set_encoder_mode story and call dpu_encoder_setup right from the
_dpu_kms_initialize_dsi() (or _dpu_kms_initialize_displayport()),
supporting multiple outputs becomes an easy task.
Okay got it, I think it will become more clear once he posts.
---
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 89
++++++++++++-------------
1 file changed, 44 insertions(+), 45 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index 1d3a4f395e74..b63e1c948ff2 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -471,30 +471,55 @@ static int _dpu_kms_initialize_dsi(struct
drm_device *dev,
struct dpu_kms *dpu_kms)
{
struct drm_encoder *encoder = NULL;
+ struct msm_display_info info;
int i, rc = 0;
if (!(priv->dsi[0] || priv->dsi[1]))
return rc;
- /*TODO: Support two independent DSI connectors */
- encoder = dpu_encoder_init(dev, DRM_MODE_ENCODER_DSI);
- if (IS_ERR(encoder)) {
- DPU_ERROR("encoder init failed for dsi display\n");
- return PTR_ERR(encoder);
- }
-
- priv->encoders[priv->num_encoders++] = encoder;
-
for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
if (!priv->dsi[i])
continue;
+ if (!encoder) {
+ encoder = dpu_encoder_init(dev, DRM_MODE_ENCODER_DSI);
+ if (IS_ERR(encoder)) {
+ DPU_ERROR("encoder init failed for dsi display\n");
+ return PTR_ERR(encoder);
+ }
+
+ priv->encoders[priv->num_encoders++] = encoder;
+
+ memset(&info, 0, sizeof(info));
+ info.intf_type = encoder->encoder_type;
+ info.capabilities = msm_dsi_is_cmd_mode(priv->dsi[i]) ?
+ MSM_DISPLAY_CAP_CMD_MODE :
+ MSM_DISPLAY_CAP_VID_MODE;
+ }
+
rc = msm_dsi_modeset_init(priv->dsi[i], dev, encoder);
if (rc) {
DPU_ERROR("modeset_init failed for dsi[%d], rc = %d\n",
i, rc);
break;
}
+
+ info.h_tile_instance[info.num_of_h_tiles++] = i;
+
+ if (!msm_dsi_is_dual_dsi(priv->dsi[i])) {
I would like to clarify the terminology of dual_dsi in the current DSI
driver before the rest of the reviews.
Today IS_DUAL_DSI() means that two DSIs are driving the same display
and the two DSIs are operating in master-slave mode
and are being driven by the same PLL.
Yes
Usually, dual independent DSI means two DSIs driving two separate
panels using two separate PLLs ( DSI0 with PLL0 and DSI1 with PLL1)
Let's stop calling it 'dual'. I'd suggest to continue using what was
there in the source file: 'two independent DSI'.
I assume thats happening due to the foll logic and both DSI PHYs are
operating in STANDALONE mode:
if (!IS_DUAL_DSI()) {
ret = msm_dsi_host_register(msm_dsi->host, true);
if (ret)
return ret;
msm_dsi_phy_set_usecase(msm_dsi->phy,
MSM_DSI_PHY_STANDALONE);
ret = msm_dsi_host_set_src_pll(msm_dsi->host, msm_dsi->phy);
Yes. If we have two independent DSI outputs, we'd like them to work in
STANDALONE mode.
+ rc = dpu_encoder_setup(dev, encoder, &info);
+ if (rc)
+ DPU_ERROR("failed to setup DPU encoder %d: rc:%d\n",
+ encoder->base.id, rc);
+ encoder = NULL;
+ }
+ }
+
+ if (encoder) {
We will hit this case only for split-DSI right? ( that is two DSIs
driving the same panel ).
Yes, only in this case.
Even single DSI will be created in the above loop now. So this looks a
bit confusing at the moment.
What is so confusing? I can probably add a comment there. If the
encoder drivers single DSI output, we setup it after creating the DSI.
If the encoder drives dual DSI outpu, we have to setup it after
creating both DSI outputs.
Its not just this loop and this small piece of code. Lets look at
dsi_manager.c.
static int dsi_mgr_setup_components(int id)
{
struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
struct msm_dsi *other_dsi = dsi_mgr_get_other_dsi(id);
struct msm_dsi *clk_master_dsi = dsi_mgr_get_dsi(DSI_CLOCK_MASTER);
struct msm_dsi *clk_slave_dsi = dsi_mgr_get_dsi(DSI_CLOCK_SLAVE);
int ret;
if (!IS_DUAL_DSI()) {
ret = msm_dsi_host_register(msm_dsi->host, true);
if (ret)
return ret;
msm_dsi_phy_set_usecase(msm_dsi->phy, MSM_DSI_PHY_STANDALONE);
ret = msm_dsi_host_set_src_pll(msm_dsi->host, msm_dsi->phy);
} else if (!other_dsi) {
Here you are actually hitting this condition even though you are
operating in dual dsi mode.
But because of the current terminology, it seems like this use-case is
not dual DSI but it actually is.
So the confusion is more in the DSI driver than in this loop where you
are calling dpu_encoder_setup()
For this loop a comment should be good enough.
I have tried calling dpu_encoder_setup from a separate if/loop
condition, but it resulted in even uglier code.
I think we need to be more clear on dual-DSI Vs split-DSI to avoid
confusion in the code about which one means what and the one
which we are currently using. So what about having IS_DUAL_DSI() and
IS_SPLIT_DSI() to distinguish the terminologies and chaging
DSI driver accordingly.
The word 'SPLIT' is already overloaded in my opinion. I'd prefer to
keep on using 'dual DSI' for the master/slave case and not to use
'dual' for just two standalone DSI interfaces.
Ok, if SPLIT is overloaded how about using IS_DUAL_DSI() and adding one
more condition like IS_DUAL_DSI_SYNC()
to emphasize that both the DSIs are not independent and are operating in
sync.
Like the above condition i mentioned in dsi_manager there are many more
places where identifying two independent DSIs
and two DSIs operating together for a single panel will be useful in my
opinion.
So rather than leaving comments everywhere in the dsi code, I was
suggesting a different terminology.
In this series, the only change which will happen will be that this API
will change a bit but I dont think its a big change.
+bool msm_dsi_is_dual_dsi(struct msm_dsi *msm_dsi)
+{
+ return IS_DUAL_DSI();
+}
+ rc = dpu_encoder_setup(dev, encoder, &info);
+ if (rc)
+ DPU_ERROR("failed to setup DPU encoder %d: rc:%d\n",
+ encoder->base.id, rc);
}
return rc;
@@ -505,6 +530,7 @@ static int _dpu_kms_initialize_displayport(struct
drm_device *dev,
struct dpu_kms *dpu_kms)
{
struct drm_encoder *encoder = NULL;
+ struct msm_display_info info;
int rc = 0;
if (!priv->dp)
@@ -516,6 +542,7 @@ static int _dpu_kms_initialize_displayport(struct
drm_device *dev,
return PTR_ERR(encoder);
}
+ memset(&info, 0, sizeof(info));
rc = msm_dp_modeset_init(priv->dp, dev, encoder);
if (rc) {
DPU_ERROR("modeset_init failed for DP, rc = %d\n", rc);
@@ -524,6 +551,14 @@ static int
_dpu_kms_initialize_displayport(struct
drm_device *dev,
}
priv->encoders[priv->num_encoders++] = encoder;
+
+ info.num_of_h_tiles = 1;
+ info.capabilities = MSM_DISPLAY_CAP_VID_MODE;
+ info.intf_type = encoder->encoder_type;
+ rc = dpu_encoder_setup(dev, encoder, &info);
+ if (rc)
+ DPU_ERROR("failed to setup DPU encoder %d: rc:%d\n",
+ encoder->base.id, rc);
return rc;
}
@@ -726,41 +761,6 @@ static void dpu_kms_destroy(struct msm_kms *kms)
msm_kms_destroy(&dpu_kms->base);
}
-static void _dpu_kms_set_encoder_mode(struct msm_kms *kms,
- struct drm_encoder *encoder,
- bool cmd_mode)
-{
- struct msm_display_info info;
- struct msm_drm_private *priv = encoder->dev->dev_private;
- int i, rc = 0;
-
- memset(&info, 0, sizeof(info));
-
- info.intf_type = encoder->encoder_type;
- info.capabilities = cmd_mode ? MSM_DISPLAY_CAP_CMD_MODE :
- MSM_DISPLAY_CAP_VID_MODE;
-
- switch (info.intf_type) {
- case DRM_MODE_ENCODER_DSI:
- /* TODO: No support for DSI swap */
- for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
- if (priv->dsi[i]) {
- info.h_tile_instance[info.num_of_h_tiles] = i;
- info.num_of_h_tiles++;
- }
- }
- break;
- case DRM_MODE_ENCODER_TMDS:
- info.num_of_h_tiles = 1;
- break;
- }
-
- rc = dpu_encoder_setup(encoder->dev, encoder, &info);
- if (rc)
- DPU_ERROR("failed to setup DPU encoder %d: rc:%d\n",
- encoder->base.id, rc);
-}
-
It seems we can get rid of set_encoder_mode for DP because the way we
are using it today seems not right.
Ideally, the purpose was that once we read the EDID, the information
we read like the tile group etc
can be used when we are setting up the encoder. But today, we are just
hard-coding the number of tiles.
But I just think whether looking ahead, we should still have some
callback which can be called after
EDID has been read instead of doing it in
_dpu_kms_initialize_displayport. Perhaps that can be a separate patch.
For the MST support? It is definitely a separate patch. For now we
want to be able to drive a much simpler config: SST on several
connected DPs.
Agreed on this.
static irqreturn_t dpu_irq(struct msm_kms *kms)
{
struct dpu_kms *dpu_kms = to_dpu_kms(kms);
@@ -863,7 +863,6 @@ static const struct msm_kms_funcs kms_funcs = {
.get_format = dpu_get_msm_format,
.round_pixclk = dpu_kms_round_pixclk,
.destroy = dpu_kms_destroy,
- .set_encoder_mode = _dpu_kms_set_encoder_mode,
I would like to get Rob's comment on why we had set_encoder_mode in
the first place. Its there even in mdp5.
in current msm dsi, the dsi bind will happen only after the panel has
attached
and the msm_drv's bind will happen only after that since its the
component master
in that case what was the need for set_encoder_mode because we will
know the panel's video/cmd mode in the dsi_bind call
am i missing something about why mdp5 had this?
As discussed with Rob on IRC, we both dont fully recall why this
set_encoder_mode callback was added for mdp5.
DPU just carried this forward from mdp5.
So to be safe, maybe we can just validate this once on mdp5 to make sure
it doesnt break.
Otherwise this part of removing the set_encoder_mode seems fine with me.
From the dpu perspective, since dsi_bind() happens only once panel
has attached.
.snapshot = dpu_kms_mdp_snapshot,
#ifdef CONFIG_DEBUG_FS
.debugfs_init = dpu_kms_debugfs_init,
