TDA4VM: Question about Csitx Lane Speed Configuration

zheng huicheng

Part Number: TDA4VM

Hi TI's expert,

I try to use tivxCsitxNode to transfer the image (2560*2560 UYVY), the verion of SDK is 7.03. And I also have patched the file 0001-CSITX-DRV-Bug-Fix-PDK-9694-CSITX-CSITX-supports-only.patch in SDK.

The configuration of tivxCsitxNode is as follows,

tivx_csitx_params_init(&local_csitx_config);

local_csitx_config.numInst = 1U;

local_csitx_config.numCh = 1U;

local_csitx_config.instId[0U] = 0U;

local_csitx_config.instCfg[0U].rxCompEnable = (uint32_t)vx_true_e;

local_csitx_config.instCfg[0U].rxv1p3MapEnable = (uint32_t)vx_true_e;

local_csitx_config.instCfg[0U].laneBandSpeed = TIVX_CSITX_LANE_BAND_SPEED_770_TO_870_MBPS;

local_csitx_config.instCfg[0U].numDataLanes = 4U;

for (loopCnt = 0U; loopCnt < local_csitx_config.instCfg[0U].numDataLanes; loopCnt++)

{

local_csitx_config.instCfg[0U].lanePolarityCtrl[loopCnt] = 0u;

}

for (loopCnt = 0U; loopCnt < 1; loopCnt++)

{

local_csitx_config.chVcNum[loopCnt] = loopCnt;

local_csitx_config.chInstMap[loopCnt] = 0;

}

and data not received at csitx output interface.

Then I try to slow down the laneBandSpeed, In these cases, data can be received normally,

a) CSITX_LANE_BAND_SPEED_560_TO_640_MBPS -------> 2560*2560*30fps UYVY

b) CSITX_LANE_BAND_SPEED_510_TO_560_MBPS -------> 2560*2560*25fps UYVY

I tried to check the previous E2E questions and found that the calculation formula of lane speed is as follows,

w * h * fps * bpp * blanking / (1024 * 1024 * lane_num) or w * h * fps * bpp * blanking / (1000 * 1000 * lane_num)

According to the formula, the Lane Speed should be the following values

2560 * 2560 * 30 * 16 * 1.2 / (1024 * 1024 * 4) = 900 MBPS and 2560 * 2560 * 25 * 16 * 1.2 / (1024 * 1024 * 4) = 750 MBPS

2560 * 2560 * 30 * 16 * 1.2 / (1000 * 1000 * 4) = 943.72 MBPS and 2560 * 2560 * 25 * 16 * 1.2 / (1000 * 1000 * 4) = 786.43 MBPS

So is the above formula correct? If it is wrong, how should it be calculated?

Best Regards!

over 3 years ago

0 Brijesh Jadav over 3 years ago

TI__Guru**** 477235 points

Hi,

Above formula is correct. 560 to 640Mbps seems very less for 2560x2560 resolution.. It might output, but not at the correct fps. Could you please check if you are getting correct fps?

Regards,

Brijesh

0 zheng huicheng over 3 years ago in reply to Brijesh Jadav

Prodigy 200 points

Hi Brijesh,

Thanks for your reply!

Our hardware interfaces are as follows,

tda4 Other Board

CSI ----> UB953 (Synchronous) ===> UB960(Non-synchronous, REFCLOCK = 25Mhz) ------> Other CPU ------> display

I tried to test all the rates as follows, fps of recving by reading the register 0x91 for UB960 and fps of sending by the function

appPerfPointPrintFPS() in tda4.

Formula 1 = w * h * fps * bpp * blanking / (1024 * 1024 * lane_num)

Formula 2 = w * h * fps * bpp * blanking / (1000 * 1000 * lane_num)

No.	DefaultInfo List	Mbps	Fps 2 By Formula 1	Fps By Formula 2	Fps For UB960 Recv	Fps For UB953 Send
1	CSITX_LANE_BAND_SPEED_80_TO_100_MBPS	100	3.33	3.18	5	4.73
2	CSITX_LANE_BAND_SPEED_100_TO_120_MBPS	120	4.00	3.81	6	5.64
3	CSITX_LANE_BAND_SPEED_120_TO_160_MBPS	150	5.00	4.77	8	7
4	CSITX_LANE_BAND_SPEED_160_TO_200_MBPS	200	6.67	6.36	10	9.16
5	CSITX_LANE_BAND_SPEED_200_TO_240_MBPS	220	7.33	6.99	11	10.2
6	CSITX_LANE_BAND_SPEED_240_TO_320_MBPS	300	10.00	9.54	15	13.4
7	CSITX_LANE_BAND_SPEED_320_TO_390_MBPS	350	11.67	11.13	17	15.36
8	CSITX_LANE_BAND_SPEED_390_TO_450_MBPS	400	13.33	12.72	19	17.29
9	CSITX_LANE_BAND_SPEED_450_TO_510_MBPS	500	16.67	15.89	23	21.2
10	CSITX_LANE_BAND_SPEED_510_TO_560_MBPS	550	18.33	17.48	25	22.9
11	CSITX_LANE_BAND_SPEED_560_TO_640_MBPS	600	20.00	19.07	28	24.65
12	CSITX_LANE_BAND_SPEED_640_TO_690_MBPS	650	21.67	20.66	29	26.5
13	CSITX_LANE_BAND_SPEED_690_TO_770_MBPS	700	23.33	22.25	31	27.91
14	CSITX_LANE_BAND_SPEED_770_TO_870_MBPS	800	26.67	25.43	35	31.13
15	CSITX_LANE_BAND_SPEED_870_TO_950_MBPS	900	30.00	28.61	38	34.21
16	CSITX_LANE_BAND_SPEED_950_TO_1000_MBPS	1000	33.33	31.79	41	36.28
17	CSITX_LANE_BAND_SPEED_1000_TO_1200_MBPS	1188	39.60	37.77	41	36.9
18	CSITX_LANE_BAND_SPEED_1200_TO_1400_MBPS	1300	43.33	41.33	40	36.1
19	CSITX_LANE_BAND_SPEED_1400_TO_1600_MBPS	1500	50.00	47.68	41	36.39
20	CSITX_LANE_BAND_SPEED_1600_TO_1800_MBPS	1600	53.33	50.86	40	36.11
21	CSITX_LANE_BAND_SPEED_1800_TO_2000_MBPS	1800	60.00	57.22	40	36.32
22	CSITX_LANE_BAND_SPEED_2000_TO_2200_MBPS	2000	66.67	63.58	40	36.18
23	CSITX_LANE_BAND_SPEED_2200_TO_2500_MBPS	2500	83.33	79.47	40	36

The green background indicates that it can be displayed normally, and the others not.

The red background indicates that the fps can not increase, I guess it may exceed the maximum serializer speed for 4.16Gbps.

The yellow background Unable to display normally which I am confused!

Can you help me that why do the speed of yellow background Unable to display normally?

Looking for your reply!

Best regards!

0 Brijesh Jadav over 3 years ago in reply to zheng huicheng

TI__Guru**** 477235 points

Hi Zheng,

How do you calculate fps at ub953? Is it what you are sending out in OpenVX?

I think fps in ub960 cannot be float number, so there could be difference of 1fps in ub960..

I think we can ignore lane speed marked as red, because they most likely exceed max speed..

When you say speed marked with yellow does not display properly, what does it mean? Do you get correct frame captured on ub960? When you use these speeds, is it this within the limit of 1.5Gbps CSI output of ub960 (depending on the reference clock used)?

Can you please check if ub960 reporting any error status?

Regards,

Brijesh

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TDA4VM: Question about Csitx Lane Speed Configuration