Re: [RFC PATCH 5/7] drm/msm/dpu: Document and enable TEAR interrupts on DSI interfaces

[Dmitry Baryshkov <dmitry.baryshkov@linaro.org>]

On 13/02/2023 21:37, Jessica Zhang wrote:
> 
> 
> On 12/31/2022 1:50 PM, Marijn Suijten wrote:
>> All SoCs since DPU 5.0.0 (and seemingly up until and including 6.0.0,
>> but excluding 7.x.x) have the tear interrupt and control registers moved
>> out of the PINGPONG block and into the INTF block.  Wire up the
>> necessary interrupts and IRQ masks on all supported hardware.
> 
> Hi Marijn,
> 
> Thanks for the patch.
> 
> I saw that in your commit msg, you mentioned that 7.x doesn't have 
> tearcheck in the INTF block -- can you double check that this is correct?
> 
> I'm working on SM8350 (DPU v7) and I'm seeing that it does have 
> tearcheck in INTF block.

I confirm, according to the vendor drivers INTF TE should be used for 
all DPU >= 5.0, including 7.x and 8.x

However I think I know what Marijn meant here. For 5.x and 6.x these 
IRQs are handled at the address MDSS + 0x6e800 / + 0x6e900 (which means 
offset here should 0x6d800 and 0x6d900) for INTF_1 and INTF_2. Since DPU 
7.x these IRQ registers were moved close to the main INTF block (0x36800 
and 0x37800 = INTF + 0x800).

> 
>>
>> Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
>> ---
>>   .../gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c    | 78 +++++++++++--------
>>   .../gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h    |  6 +-
>>   .../gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.c | 12 +++
>>   .../gpu/drm/msm/disp/dpu1/dpu_hw_interrupts.h |  2 +
>>   drivers/gpu/drm/msm/disp/dpu1/dpu_hwio.h      |  3 +
>>   5 files changed, 68 insertions(+), 33 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c 
>> b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
>> index 1cfe94494135..b9b9b5b0b615 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.c
>> @@ -86,6 +86,15 @@
>>   #define INTF_SC7280_MASK INTF_SC7180_MASK | BIT(DPU_DATA_HCTL_EN)
>> +#define IRQ_MSM8998_MASK (BIT(MDP_SSPP_TOP0_INTR) | \
>> +             BIT(MDP_SSPP_TOP0_INTR2) | \
>> +             BIT(MDP_SSPP_TOP0_HIST_INTR) | \
>> +             BIT(MDP_INTF0_INTR) | \
>> +             BIT(MDP_INTF1_INTR) | \
>> +             BIT(MDP_INTF2_INTR) | \
>> +             BIT(MDP_INTF3_INTR) | \
>> +             BIT(MDP_INTF4_INTR))
>> +
>>   #define IRQ_SDM845_MASK (BIT(MDP_SSPP_TOP0_INTR) | \
>>                BIT(MDP_SSPP_TOP0_INTR2) | \
>>                BIT(MDP_SSPP_TOP0_HIST_INTR) | \
>> @@ -100,13 +109,15 @@
>>   #define IRQ_QCM2290_MASK (BIT(MDP_SSPP_TOP0_INTR) | \
>>                BIT(MDP_SSPP_TOP0_INTR2) | \
>>                BIT(MDP_SSPP_TOP0_HIST_INTR) | \
>> -             BIT(MDP_INTF1_INTR))
>> +             BIT(MDP_INTF1_INTR) | \
>> +             BIT(MDP_INTF1_TEAR_INTR))
>>   #define IRQ_SC7180_MASK (BIT(MDP_SSPP_TOP0_INTR) | \
>>                BIT(MDP_SSPP_TOP0_INTR2) | \
>>                BIT(MDP_SSPP_TOP0_HIST_INTR) | \
>>                BIT(MDP_INTF0_INTR) | \
>> -             BIT(MDP_INTF1_INTR))
>> +             BIT(MDP_INTF1_INTR) | \
>> +             BIT(MDP_INTF1_TEAR_INTR))
>>   #define IRQ_SC7280_MASK (BIT(MDP_SSPP_TOP0_INTR) | \
>>                BIT(MDP_SSPP_TOP0_INTR2) | \
>> @@ -120,7 +131,9 @@
>>                BIT(MDP_SSPP_TOP0_HIST_INTR) | \
>>                BIT(MDP_INTF0_INTR) | \
>>                BIT(MDP_INTF1_INTR) | \
>> +             BIT(MDP_INTF1_TEAR_INTR) | \
>>                BIT(MDP_INTF2_INTR) | \
>> +             BIT(MDP_INTF2_TEAR_INTR) | \
>>                BIT(MDP_INTF3_INTR) | \
>>                BIT(MDP_INTF4_INTR))
>> @@ -129,7 +142,9 @@
>>                 BIT(MDP_SSPP_TOP0_HIST_INTR) | \
>>                 BIT(MDP_INTF0_INTR) | \
>>                 BIT(MDP_INTF1_INTR) | \
>> +              BIT(MDP_INTF1_TEAR_INTR) | \
>>                 BIT(MDP_INTF2_INTR) | \
>> +              BIT(MDP_INTF2_TEAR_INTR) | \
>>                 BIT(MDP_INTF3_INTR) | \
>>                 BIT(MDP_INTF4_INTR) | \
>>                 BIT(MDP_INTF5_INTR) | \
>> @@ -1300,63 +1315,64 @@ static struct dpu_dsc_cfg sdm845_dsc[] = {
>>   /*************************************************************
>>    * INTF sub blocks config
>>    *************************************************************/
>> -#define INTF_BLK(_name, _id, _base, _type, _ctrl_id, _progfetch, 
>> _features, _reg, _underrun_bit, _vsync_bit) \
>> +#define INTF_BLK(_name, _id, _base, _len, _type, _ctrl_id, 
>> _progfetch, _features, _reg, _underrun_bit, _vsync_bit, _tear_reg, 
>> _tear_rd_ptr_bit) \
>>       {\
>>       .name = _name, .id = _id, \
>> -    .base = _base, .len = 0x280, \
>> +    .base = _base, .len = _len, \
>>       .features = _features, \
>>       .type = _type, \
>>       .controller_id = _ctrl_id, \
>>       .prog_fetch_lines_worst_case = _progfetch, \
>>       .intr_underrun = DPU_IRQ_IDX(_reg, _underrun_bit), \
>>       .intr_vsync = DPU_IRQ_IDX(_reg, _vsync_bit), \
>> +    .intr_tear_rd_ptr = DPU_IRQ_IDX(_tear_reg, _tear_rd_ptr_bit), \
>>       }
>>   static const struct dpu_intf_cfg msm8998_intf[] = {
>> -    INTF_BLK("intf_0", INTF_0, 0x6A000, INTF_DP, 0, 25, 
>> INTF_SDM845_MASK, MDP_SSPP_TOP0_INTR, 24, 25),
>> -    INTF_BLK("intf_1", INTF_1, 0x6A800, INTF_DSI, 0, 25, 
>> INTF_SDM845_MASK, MDP_SSPP_TOP0_INTR, 26, 27),
>> -    INTF_BLK("intf_2", INTF_2, 0x6B000, INTF_DSI, 1, 25, 
>> INTF_SDM845_MASK, MDP_SSPP_TOP0_INTR, 28, 29),
>> -    INTF_BLK("intf_3", INTF_3, 0x6B800, INTF_HDMI, 0, 25, 
>> INTF_SDM845_MASK, MDP_SSPP_TOP0_INTR, 30, 31),
>> +    INTF_BLK("intf_0", INTF_0, 0x6A000, 0x268, INTF_DP, 0, 25, 
>> INTF_SDM845_MASK, MDP_SSPP_TOP0_INTR, 24, 25, -1, -1),
> 
> Just wondering, how were the lengths calculated for the INTF blocks? The 
> values in general seem a little off to me.
> 
> For example, I'm looking downstream and it seems to me that the length 
> for the INTF_0 on MSM8998 should be 0x280. Similarly for SC7280, I'm 
> seeing that length for INTF + tearcheck should be 0x2c4.

We have discussed INTF lengths in [1]. The current understanding of the 
block lengths can be found at [2]. Please comment there if any of the 
fixed lengths sounds incorrect to you.

[1] https://patchwork.freedesktop.org/patch/522187/
[2] https://patchwork.freedesktop.org/patch/522227/

[skipped the rest]

-- 
With best wishes
Dmitry