[Freedreno] [RFC 1/4] drm/msm/dpu: introduce a wb_idx to be used for writeback interfaces

Abhinav Kumar quic_abhinavk at quicinc.com
Fri Apr 22 01:59:04 UTC 2022



On 4/21/2022 5:22 PM, Dmitry Baryshkov wrote:
> On Fri, 22 Apr 2022 at 02:07, Abhinav Kumar <quic_abhinavk at quicinc.com> wrote:
>>
>> Hi Dmitry
>>
>> Thanks for the review.
>>
>> One question below.
>>
>> On 4/21/2022 3:40 PM, Dmitry Baryshkov wrote:
>>> On 21/04/2022 23:48, Abhinav Kumar wrote:
>>>> Using intf_idx even for writeback interfaces is confusing
>>>> because intf_idx is of type enum dpu_intf but the index used
>>>> for writeback is of type enum dpu_wb.
>>>>
>>>> In addition, this makes it easier to separately check the
>>>> availability of the two as its possible that there are boards
>>>> which don't have any physical display connected but can still
>>>> work in writeback mode.
>>>>
>>>> Signed-off-by: Abhinav Kumar <quic_abhinavk at quicinc.com>
>>>
>>> Looks good, two minor issues bellow.
>>>
>>> With them fixed, I'd even squash this patch into the corresponding patch
>>> of the previous patchset.
>>>
>>>> ---
>>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c      | 62
>>>> +++++++++++++-----------
>>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h |  4 ++
>>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h           |  2 +-
>>>>    3 files changed, 40 insertions(+), 28 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> index 9c12841..054d7e4 100644
>>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
>>>> @@ -962,7 +962,6 @@ static void
>>>> dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
>>>>        struct dpu_hw_blk *hw_dsc[MAX_CHANNELS_PER_ENC];
>>>>        int num_lm, num_ctl, num_pp, num_dsc;
>>>>        unsigned int dsc_mask = 0;
>>>> -    enum dpu_hw_blk_type blk_type;
>>>>        int i;
>>>>        if (!drm_enc) {
>>>> @@ -1044,17 +1043,11 @@ static void
>>>> dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
>>>>            phys->hw_pp = dpu_enc->hw_pp[i];
>>>>            phys->hw_ctl = to_dpu_hw_ctl(hw_ctl[i]);
>>>> -        if (dpu_encoder_get_intf_mode(&dpu_enc->base) ==
>>>> INTF_MODE_WB_LINE)
>>>> -            blk_type = DPU_HW_BLK_WB;
>>>> -        else
>>>> -            blk_type = DPU_HW_BLK_INTF;
>>>> +        if (phys->intf_idx >= INTF_0 && phys->intf_idx < INTF_MAX)
>>>> +            phys->hw_intf = dpu_rm_get_intf(&dpu_kms->rm,
>>>> phys->intf_idx);
>>>> -        if (phys->intf_idx >= INTF_0 && phys->intf_idx < INTF_MAX) {
>>>> -            if (blk_type == DPU_HW_BLK_INTF)
>>>> -                phys->hw_intf = dpu_rm_get_intf(&dpu_kms->rm,
>>>> phys->intf_idx);
>>>> -            else if (blk_type == DPU_HW_BLK_WB)
>>>> -                phys->hw_wb = dpu_rm_get_wb(&dpu_kms->rm,
>>>> phys->intf_idx);
>>>> -        }
>>>> +        if (phys->wb_idx >= WB_0 && phys->wb_idx < WB_MAX)
>>>> +            phys->hw_wb = dpu_rm_get_wb(&dpu_kms->rm, phys->wb_idx);
>>>
>>> We also need a check for if (phus->hw_intf && phys->hw_wb) HERE
>>
>> So there is an error if
>>
>> 1) Neither wb NOR intf are present
>> 2) Both wb AND intf are present for the physical encoder?
>>
>> The second check is okay for now to add but considering concurrent
>> writeback then that wouldn't assumption be wrong since both physical and
>> wb interfaces can go with the same encoder?
> 
> To the same encoder, but not to the same physical encoder. Here we
> check the phys_enc parameters.

Ok got it, let me re-spin this RFC with patches 2 & 3 squashed.
Get the acks on them.

Then will absorb into WB series and re-post it.

> 
>>
>>>
>>>>            if (!phys->hw_intf && !phys->hw_wb) {
>>>>                DPU_ERROR_ENC(dpu_enc,
>>>> @@ -1201,7 +1194,7 @@ static void dpu_encoder_virt_disable(struct
>>>> drm_encoder *drm_enc)
>>>>        mutex_unlock(&dpu_enc->enc_lock);
>>>>    }
>>>> -static enum dpu_intf dpu_encoder_get_intf_or_wb(struct dpu_mdss_cfg
>>>> *catalog,
>>>> +static enum dpu_intf dpu_encoder_get_intf(struct dpu_mdss_cfg *catalog,
>>>>            enum dpu_intf_type type, u32 controller_id)
>>>>    {
>>>>        int i = 0;
>>>> @@ -1213,16 +1206,28 @@ static enum dpu_intf
>>>> dpu_encoder_get_intf_or_wb(struct dpu_mdss_cfg *catalog,
>>>>                    return catalog->intf[i].id;
>>>>                }
>>>>            }
>>>> -    } else {
>>>> -        for (i = 0; i < catalog->wb_count; i++) {
>>>> -            if (catalog->wb[i].id == controller_id)
>>>> -                return catalog->wb[i].id;
>>>> -        }
>>>>        }
>>>>        return INTF_MAX;
>>>>    }
>>>> +static enum dpu_wb dpu_encoder_get_wb(struct dpu_mdss_cfg *catalog,
>>>> +        enum dpu_intf_type type, u32 controller_id)
>>>> +{
>>>> +    int i = 0;
>>>> +
>>>> +    if (type != INTF_WB)
>>>> +        goto end;
>>>> +
>>>> +    for (i = 0; i < catalog->wb_count; i++) {
>>>> +        if (catalog->wb[i].id == controller_id)
>>>> +            return catalog->wb[i].id;
>>>> +    }
>>>> +
>>>> +end:
>>>> +    return WB_MAX;
>>>
>>> I'd return INTF_NONE/WB_NONE if the interface or WB unit was not found.
>> ack, i guess in that case even the places checking the return value of
>> this function need to be changed.
> 
> Yes, of course.
> 
>>>
>>>> +}
>>>> +
>>>>    static void dpu_encoder_vblank_callback(struct drm_encoder *drm_enc,
>>>>            struct dpu_encoder_phys *phy_enc)
>>>>    {
>>>> @@ -2249,18 +2254,21 @@ static int dpu_encoder_setup_display(struct
>>>> dpu_encoder_virt *dpu_enc,
>>>>            DPU_DEBUG("h_tile_instance %d = %d, split_role %d\n",
>>>>                    i, controller_id, phys_params.split_role);
>>>> -        /*
>>>> -         * FIXME: have separate intf_idx and wb_idx to avoid using
>>>> -         * enum dpu_intf type for wb_idx and also to be able to
>>>> -         * not bail out when there is no intf for boards which dont
>>>> -         * have a display connected to them.
>>>> -         * Having a valid wb_idx but not a intf_idx can be a valid
>>>> -         * combination moving forward.
>>>> -         */
>>>> -        phys_params.intf_idx =
>>>> dpu_encoder_get_intf_or_wb(dpu_kms->catalog,
>>>> +        phys_params.intf_idx = dpu_encoder_get_intf(dpu_kms->catalog,
>>>>                                                        intf_type,
>>>>                                                        controller_id);
>>>> -        if (phys_params.intf_idx == INTF_MAX) {
>>>> +
>>>> +        phys_params.wb_idx = dpu_encoder_get_wb(dpu_kms->catalog,
>>>> +                intf_type, controller_id);
>>>> +        /*
>>>> +         * For boards which have no physical displays, having no
>>>> interface
>>>> +         * is fine because it can still be used with just writeback.
>>>> +         * If we try without a display on a board which uses a DPU in
>>>> which
>>>> +         * writeback is not supported, then this will still fail as
>>>> it will not
>>>> +         * find any writeback in the catalog.
>>>> +         */
>>>> +        if ((phys_params.intf_idx == INTF_MAX) &&
>>>> +                (phys_params.wb_idx == WB_MAX)) {
>>>>                DPU_ERROR_ENC(dpu_enc, "could not get intf or wb: type
>>>> %d, id %d\n",
>>>>                              intf_type, controller_id);
>>>>                ret = -EINVAL;
>>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>>>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>>>> index 04d037e..f2af07d 100644
>>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
>>>> @@ -181,6 +181,7 @@ enum dpu_intr_idx {
>>>>     * @split_role:        Role to play in a split-panel configuration
>>>>     * @intf_mode:        Interface mode
>>>>     * @intf_idx:        Interface index on dpu hardware
>>>> + * @wb_idx:            Writeback index on dpu hardware
>>>>     * @enc_spinlock:    Virtual-Encoder-Wide Spin Lock for IRQ purposes
>>>>     * @enable_state:    Enable state tracking
>>>>     * @vblank_refcount:    Reference count of vblank request
>>>> @@ -209,6 +210,7 @@ struct dpu_encoder_phys {
>>>>        enum dpu_enc_split_role split_role;
>>>>        enum dpu_intf_mode intf_mode;
>>>>        enum dpu_intf intf_idx;
>>>> +    enum dpu_wb wb_idx;
>>>>        spinlock_t *enc_spinlock;
>>>>        enum dpu_enc_enable_state enable_state;
>>>>        atomic_t vblank_refcount;
>>>> @@ -275,6 +277,7 @@ struct dpu_encoder_phys_cmd {
>>>>     * @parent_ops:        Callbacks exposed by the parent to the phys_enc
>>>>     * @split_role:        Role to play in a split-panel configuration
>>>>     * @intf_idx:        Interface index this phys_enc will control
>>>> + * @wb_idx:            Writeback index this phys_enc will control
>>>>     * @enc_spinlock:    Virtual-Encoder-Wide Spin Lock for IRQ purposes
>>>>     */
>>>>    struct dpu_enc_phys_init_params {
>>>> @@ -283,6 +286,7 @@ struct dpu_enc_phys_init_params {
>>>>        const struct dpu_encoder_virt_ops *parent_ops;
>>>>        enum dpu_enc_split_role split_role;
>>>>        enum dpu_intf intf_idx;
>>>> +    enum dpu_wb wb_idx;
>>>>        spinlock_t *enc_spinlock;
>>>>    };
>>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
>>>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
>>>> index ba82e54..2f34a31 100644
>>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
>>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.h
>>>> @@ -103,7 +103,7 @@ static inline struct dpu_hw_intf
>>>> *dpu_rm_get_intf(struct dpu_rm *rm, enum dpu_in
>>>>     * @rm: DPU Resource Manager handle
>>>>     * @wb_idx: WB index
>>>>     */
>>>> -static inline struct dpu_hw_wb *dpu_rm_get_wb(struct dpu_rm *rm, enum
>>>> dpu_intf wb_idx)
>>>> +static inline struct dpu_hw_wb *dpu_rm_get_wb(struct dpu_rm *rm, enum
>>>> dpu_wb wb_idx)
>>>>    {
>>>>        return rm->hw_wb[wb_idx - WB_0];
>>>>    }
>>>
>>>
> 
> 
> 


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