[PATCH v3 1/3] drm: allow real encoder to be passed for drm_writeback_connector
Abhinav Kumar
quic_abhinavk at quicinc.com
Thu Mar 17 17:26:38 UTC 2022
Hi Laurent
Thanks for the review.
On 3/17/2022 1:51 AM, Laurent Pinchart wrote:
> Hi Abhinav,
>
> Thank you for the patch.
>
> On Wed, Mar 16, 2022 at 11:48:16AM -0700, Abhinav Kumar wrote:
>> For some vendor driver implementations, display hardware can
>> be shared between the encoder used for writeback and the physical
>> display.
>>
>> In addition resources such as clocks and interrupts can
>> also be shared between writeback and the real encoder.
>>
>> To accommodate such vendor drivers and hardware, allow
>> real encoder to be passed for drm_writeback_connector using a new
>> drm_writeback_connector_init_with_encoder() API.
>
> The commit message doesn't match the commit.
Sorry, while splitting the change , I missed this part of the commit
text. Will fix it up.
>
>> In addition, to preserve the same call flows for the existing
>> users of drm_writeback_connector_init(), also allow passing
>> possible_crtcs as a parameter so that encoder can be initialized
>> with it.
>>
>> changes in v3:
>> - allow passing possible_crtcs for existing users of
>> drm_writeback_connector_init()
>> - squash the vendor changes into the same commit so
>> that each patch in the series can compile individually
>>
>> Co-developed-by: Kandpal Suraj <suraj.kandpal at intel.com>
>> Signed-off-by: Abhinav Kumar <quic_abhinavk at quicinc.com>
>> ---
>> .../drm/arm/display/komeda/komeda_wb_connector.c | 3 +-
>> drivers/gpu/drm/arm/malidp_mw.c | 5 +-
>> drivers/gpu/drm/drm_writeback.c | 103 +++++++++++++--------
>> drivers/gpu/drm/rcar-du/rcar_du_writeback.c | 5 +-
>> drivers/gpu/drm/vc4/vc4_txp.c | 19 ++--
>> drivers/gpu/drm/vkms/vkms_writeback.c | 3 +-
>> include/drm/drm_writeback.h | 22 ++++-
>> 7 files changed, 103 insertions(+), 57 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c b/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c
>> index e465cc4..40774e6 100644
>> --- a/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c
>> +++ b/drivers/gpu/drm/arm/display/komeda/komeda_wb_connector.c
>> @@ -155,7 +155,6 @@ static int komeda_wb_connector_add(struct komeda_kms_dev *kms,
>> kwb_conn->wb_layer = kcrtc->master->wb_layer;
>>
>> wb_conn = &kwb_conn->base;
>> - wb_conn->encoder.possible_crtcs = BIT(drm_crtc_index(&kcrtc->base));
>>
>> formats = komeda_get_layer_fourcc_list(&mdev->fmt_tbl,
>> kwb_conn->wb_layer->layer_type,
>> @@ -164,7 +163,7 @@ static int komeda_wb_connector_add(struct komeda_kms_dev *kms,
>> err = drm_writeback_connector_init(&kms->base, wb_conn,
>> &komeda_wb_connector_funcs,
>> &komeda_wb_encoder_helper_funcs,
>> - formats, n_formats);
>> + formats, n_formats, BIT(drm_crtc_index(&kcrtc->base)));
>> komeda_put_fourcc_list(formats);
>> if (err) {
>> kfree(kwb_conn);
>> diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c
>> index f5847a7..b882066 100644
>> --- a/drivers/gpu/drm/arm/malidp_mw.c
>> +++ b/drivers/gpu/drm/arm/malidp_mw.c
>> @@ -208,11 +208,12 @@ int malidp_mw_connector_init(struct drm_device *drm)
>> struct malidp_drm *malidp = drm->dev_private;
>> u32 *formats;
>> int ret, n_formats;
>> + uint32_t possible_crtcs;
>>
>> if (!malidp->dev->hw->enable_memwrite)
>> return 0;
>>
>> - malidp->mw_connector.encoder.possible_crtcs = 1 << drm_crtc_index(&malidp->crtc);
>> + possible_crtcs = 1 << drm_crtc_index(&malidp->crtc);
>> drm_connector_helper_add(&malidp->mw_connector.base,
>> &malidp_mw_connector_helper_funcs);
>>
>> @@ -223,7 +224,7 @@ int malidp_mw_connector_init(struct drm_device *drm)
>> ret = drm_writeback_connector_init(drm, &malidp->mw_connector,
>> &malidp_mw_connector_funcs,
>> &malidp_mw_encoder_helper_funcs,
>> - formats, n_formats);
>> + formats, n_formats, possible_crtcs);
>
> Do you need the local variable ?
Yes, we can dtop this. I just used this instead of "1 <<
drm_crtc_index(&malidp->crtc)" to simplify it.
No strong preference.
>
>> kfree(formats);
>> if (ret)
>> return ret;
>> diff --git a/drivers/gpu/drm/drm_writeback.c b/drivers/gpu/drm/drm_writeback.c
>> index dccf4504..17c1471 100644
>> --- a/drivers/gpu/drm/drm_writeback.c
>> +++ b/drivers/gpu/drm/drm_writeback.c
>> @@ -149,36 +149,15 @@ static const struct drm_encoder_funcs drm_writeback_encoder_funcs = {
>> .destroy = drm_encoder_cleanup,
>> };
>>
>> -/**
>> - * drm_writeback_connector_init - Initialize a writeback connector and its properties
>> - * @dev: DRM device
>> - * @wb_connector: Writeback connector to initialize
>> - * @con_funcs: Connector funcs vtable
>> - * @enc_helper_funcs: Encoder helper funcs vtable to be used by the internal encoder
>> - * @formats: Array of supported pixel formats for the writeback engine
>> - * @n_formats: Length of the formats array
>> - *
>> - * This function creates the writeback-connector-specific properties if they
>> - * have not been already created, initializes the connector as
>> - * type DRM_MODE_CONNECTOR_WRITEBACK, and correctly initializes the property
>> - * values. It will also create an internal encoder associated with the
>> - * drm_writeback_connector and set it to use the @enc_helper_funcs vtable for
>> - * the encoder helper.
>> - *
>> - * Drivers should always use this function instead of drm_connector_init() to
>> - * set up writeback connectors.
>> - *
>> - * Returns: 0 on success, or a negative error code
>> - */
>> -int drm_writeback_connector_init(struct drm_device *dev,
>> - struct drm_writeback_connector *wb_connector,
>> - const struct drm_connector_funcs *con_funcs,
>> - const struct drm_encoder_helper_funcs *enc_helper_funcs,
>> - const u32 *formats, int n_formats)
>> +static int drm_writeback_connector_setup(struct drm_device *dev,
>> + struct drm_writeback_connector *wb_connector,
>> + const struct drm_connector_funcs *con_funcs, const u32 *formats,
>> + int n_formats)
>> {
>> struct drm_property_blob *blob;
>> - struct drm_connector *connector = &wb_connector->base;
>> struct drm_mode_config *config = &dev->mode_config;
>> + struct drm_connector *connector = &wb_connector->base;
>> +
>> int ret = create_writeback_properties(dev);
>>
>> if (ret != 0)
>> @@ -186,15 +165,10 @@ int drm_writeback_connector_init(struct drm_device *dev,
>>
>> blob = drm_property_create_blob(dev, n_formats * sizeof(*formats),
>> formats);
>> - if (IS_ERR(blob))
>> - return PTR_ERR(blob);
>> -
>> - drm_encoder_helper_add(&wb_connector->encoder, enc_helper_funcs);
>> - ret = drm_encoder_init(dev, &wb_connector->encoder,
>> - &drm_writeback_encoder_funcs,
>> - DRM_MODE_ENCODER_VIRTUAL, NULL);
>> - if (ret)
>> - goto fail;
>> + if (IS_ERR(blob)) {
>> + ret = PTR_ERR(blob);
>> + return ret;
>> + }
>>
>> connector->interlace_allowed = 0;
>>
>> @@ -204,7 +178,7 @@ int drm_writeback_connector_init(struct drm_device *dev,
>> goto connector_fail;
>>
>> ret = drm_connector_attach_encoder(connector,
>> - &wb_connector->encoder);
>> + wb_connector->encoder);
>> if (ret)
>> goto attach_fail;
>>
>> @@ -233,11 +207,62 @@ int drm_writeback_connector_init(struct drm_device *dev,
>> attach_fail:
>> drm_connector_cleanup(connector);
>> connector_fail:
>> - drm_encoder_cleanup(&wb_connector->encoder);
>> -fail:
>> drm_property_blob_put(blob);
>> return ret;
>> }
>> +
>> +/**
>> + * drm_writeback_connector_init - Initialize a writeback connector and its properties
>> + * using an internal encoder
>> + *
>> + * @dev: DRM device
>> + * @wb_connector: Writeback connector to initialize
>> + * @con_funcs: Connector funcs vtable
>> + * @enc_helper_funcs: Encoder helper funcs vtable to be used by the internal encoder
>> + * @formats: Array of supported pixel formats for the writeback engine
>> + * @n_formats: Length of the formats array
>> + * @possible_crtcs: possible crtcs for the internal writeback encoder
>> + *
>> + * This function creates the writeback-connector-specific properties if they
>> + * have not been already created, initializes the connector as
>> + * type DRM_MODE_CONNECTOR_WRITEBACK, and correctly initializes the property
>> + * values. It will also create an internal encoder associated with the
>> + * drm_writeback_connector and set it to use the @enc_helper_funcs vtable for
>> + * the encoder helper.
>> + *
>> + * Drivers should always use this function instead of drm_connector_init() to
>> + * set up writeback connectors.
>> + *
>> + * Returns: 0 on success, or a negative error code
>> + */
>> +int drm_writeback_connector_init(struct drm_device *dev,
>> + struct drm_writeback_connector *wb_connector,
>> + const struct drm_connector_funcs *con_funcs,
>> + const struct drm_encoder_helper_funcs *enc_helper_funcs,
>> + const u32 *formats, int n_formats, uint32_t possible_crtcs)
>> +{
>> + int ret = 0;
>> +
>> + wb_connector->encoder = &wb_connector->internal_encoder;
>> +
>> + drm_encoder_helper_add(wb_connector->encoder, enc_helper_funcs);
>> +
>> + wb_connector->encoder->possible_crtcs = possible_crtcs;
>> +
>> + ret = drm_encoder_init(dev, wb_connector->encoder,
>> + &drm_writeback_encoder_funcs,
>> + DRM_MODE_ENCODER_VIRTUAL, NULL);
>> + if (ret)
>> + return ret;
>> +
>> + ret = drm_writeback_connector_setup(dev, wb_connector, con_funcs, formats,
>> + n_formats);
>> +
>> + if (ret)
>> + drm_encoder_cleanup(wb_connector->encoder);
>> +
>> + return ret;
>> +}
>
> All this doesn't belong to this patch. Just add the possible_crtcs
> argument to drm_writeback_connector_init() in 1/3, nothing else. One
> functional change, one patch.
Ok, so let me re-factor the series like this:
1) possible_crtcs argument along with other vendor changes
2) changing encoder to a pointer with changes to vc4
3) adding a new API drm_writeback_connector_init_with_encoder() with the
cleanup in the drm_writeback
4) changing vc4 to use the new API
Let me know what you think.
>
>> EXPORT_SYMBOL(drm_writeback_connector_init);
>>
>> int drm_writeback_set_fb(struct drm_connector_state *conn_state,
>> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_writeback.c b/drivers/gpu/drm/rcar-du/rcar_du_writeback.c
>> index c79d125..1a610c0 100644
>> --- a/drivers/gpu/drm/rcar-du/rcar_du_writeback.c
>> +++ b/drivers/gpu/drm/rcar-du/rcar_du_writeback.c
>> @@ -199,8 +199,9 @@ int rcar_du_writeback_init(struct rcar_du_device *rcdu,
>> struct rcar_du_crtc *rcrtc)
>> {
>> struct drm_writeback_connector *wb_conn = &rcrtc->writeback;
>> + uint32_t possible_crtcs;
>>
>> - wb_conn->encoder.possible_crtcs = 1 << drm_crtc_index(&rcrtc->crtc);
>> + possible_crtcs = 1 << drm_crtc_index(&rcrtc->crtc);
>> drm_connector_helper_add(&wb_conn->base,
>> &rcar_du_wb_conn_helper_funcs);
>>
>> @@ -208,7 +209,7 @@ int rcar_du_writeback_init(struct rcar_du_device *rcdu,
>> &rcar_du_wb_conn_funcs,
>> &rcar_du_wb_enc_helper_funcs,
>> writeback_formats,
>> - ARRAY_SIZE(writeback_formats));
>> + ARRAY_SIZE(writeback_formats), possible_crtcs);
>
> Same here, do you need the intermediate variable ?
>
> And please add a line break after ARRAY_SIZE().
Ok will do
>
>> }
>>
>> void rcar_du_writeback_setup(struct rcar_du_crtc *rcrtc,
>> diff --git a/drivers/gpu/drm/vc4/vc4_txp.c b/drivers/gpu/drm/vc4/vc4_txp.c
>> index 9809ca3..32c4fb0 100644
>> --- a/drivers/gpu/drm/vc4/vc4_txp.c
>> +++ b/drivers/gpu/drm/vc4/vc4_txp.c
>> @@ -151,6 +151,8 @@ struct vc4_txp {
>>
>> struct platform_device *pdev;
>>
>> + struct drm_encoder drm_enc;
>> +
>> struct drm_writeback_connector connector;
>>
>> void __iomem *regs;
>> @@ -159,7 +161,7 @@ struct vc4_txp {
>>
>> static inline struct vc4_txp *encoder_to_vc4_txp(struct drm_encoder *encoder)
>> {
>> - return container_of(encoder, struct vc4_txp, connector.encoder);
>> + return container_of(encoder, struct vc4_txp, drm_enc);
>> }
>>
>> static inline struct vc4_txp *connector_to_vc4_txp(struct drm_connector *conn)
>> @@ -467,6 +469,7 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)
>> struct vc4_txp *txp;
>> struct drm_crtc *crtc;
>> struct drm_encoder *encoder;
>> + struct drm_writeback_connector *wb_conn;
>> int ret, irq;
>>
>> irq = platform_get_irq(pdev, 0);
>> @@ -492,12 +495,14 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)
>> txp->regset.regs = txp_regs;
>> txp->regset.nregs = ARRAY_SIZE(txp_regs);
>>
>> - drm_connector_helper_add(&txp->connector.base,
>> + wb_conn = &txp->connector;
>> + wb_conn->encoder = &txp->drm_enc;
>> +
>> + drm_connector_helper_add(&wb_conn->base,
>> &vc4_txp_connector_helper_funcs);
>> - ret = drm_writeback_connector_init(drm, &txp->connector,
>> - &vc4_txp_connector_funcs,
>> - &vc4_txp_encoder_helper_funcs,
>> - drm_fmts, ARRAY_SIZE(drm_fmts));
>> + ret = drm_writeback_connector_init(drm, wb_conn,
>> + &vc4_txp_connector_funcs, &vc4_txp_encoder_helper_funcs,
>> + drm_fmts, ARRAY_SIZE(drm_fmts), 0);
>
> Most of this also doesn't belong to this patch.
>
>> if (ret)
>> return ret;
>>
>> @@ -506,7 +511,7 @@ static int vc4_txp_bind(struct device *dev, struct device *master, void *data)
>> if (ret)
>> return ret;
>>
>> - encoder = &txp->connector.encoder;
>> + encoder = txp->connector.encoder;
>> encoder->possible_crtcs = drm_crtc_mask(crtc);
>>
>> ret = devm_request_irq(dev, irq, vc4_txp_interrupt, 0,
>> diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
>> index 8694227..381e7b7 100644
>> --- a/drivers/gpu/drm/vkms/vkms_writeback.c
>> +++ b/drivers/gpu/drm/vkms/vkms_writeback.c
>> @@ -140,12 +140,11 @@ int vkms_enable_writeback_connector(struct vkms_device *vkmsdev)
>> {
>> struct drm_writeback_connector *wb = &vkmsdev->output.wb_connector;
>>
>> - vkmsdev->output.wb_connector.encoder.possible_crtcs = 1;
>> drm_connector_helper_add(&wb->base, &vkms_wb_conn_helper_funcs);
>>
>> return drm_writeback_connector_init(&vkmsdev->drm, wb,
>> &vkms_wb_connector_funcs,
>> &vkms_wb_encoder_helper_funcs,
>> vkms_wb_formats,
>> - ARRAY_SIZE(vkms_wb_formats));
>> + ARRAY_SIZE(vkms_wb_formats), 1);
>> }
>> diff --git a/include/drm/drm_writeback.h b/include/drm/drm_writeback.h
>> index 9697d27..5e002bc 100644
>> --- a/include/drm/drm_writeback.h
>> +++ b/include/drm/drm_writeback.h
>> @@ -25,13 +25,29 @@ struct drm_writeback_connector {
>> struct drm_connector base;
>>
>> /**
>> - * @encoder: Internal encoder used by the connector to fulfill
>> + * @encoder: handle to drm_encoder used by the connector to fulfill
>> * the DRM framework requirements. The users of the
>> * @drm_writeback_connector control the behaviour of the @encoder
>> * by passing the @enc_funcs parameter to drm_writeback_connector_init()
>> * function.
>> + *
>> + * For some vendor drivers, the hardware resources are shared between
>> + * writeback encoder and rest of the display pipeline.
>> + * To accommodate such cases, encoder is a handle to the real encoder
>> + * hardware.
>> + *
>> + * For current existing writeback users, this shall continue to be the
>> + * embedded encoder for the writeback connector.
>> + *
>> + */
>> + struct drm_encoder *encoder;
>> +
>> + /**
>> + * @internal_encoder: internal encoder used by writeback when
>> + * a real encoder is not provided by the vendor drm drivers.
>> + * @encoder will be assigned to this for those cases.
>> */
>> - struct drm_encoder encoder;
>> + struct drm_encoder internal_encoder;
>
> None of this belong here.
Alright, will split to the next patch.
>
>>
>> /**
>> * @pixel_formats_blob_ptr:
>> @@ -150,7 +166,7 @@ int drm_writeback_connector_init(struct drm_device *dev,
>> struct drm_writeback_connector *wb_connector,
>> const struct drm_connector_funcs *con_funcs,
>> const struct drm_encoder_helper_funcs *enc_helper_funcs,
>> - const u32 *formats, int n_formats);
>> + const u32 *formats, int n_formats, uint32_t possible_crtcs);
>>
>> int drm_writeback_set_fb(struct drm_connector_state *conn_state,
>> struct drm_framebuffer *fb);
>
More information about the dri-devel
mailing list