[PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[Akash Kumar]

The current logic is rigid, setting num_fifos to fixed values:

3 for any maxburst greater than 1.
tx_fifo_resize_max_num for maxburst greater than 6.
Additionally, it did not differentiate much between bulk and
isochronous transfers, applying similar logic to both.

The new logic is more dynamic and tailored to the specific needs of
bulk and isochronous transfers:

Bulk Transfers: Ensures that num_fifos is optimized by considering
both the maxburst value and the maximum allowed number of FIFOs.

Isochronous Transfers: Ensures that num_fifos is sufficient by
considering the maxburst value and the maximum packet multiplier.

This change aims to optimize the allocation of Tx FIFOs for both bulk
and isochronous endpoints, potentially improving data transfer
efficiency and overall performance.
It also enhances support for all use cases, which can be tweaked
with DT parameters and the endpoint’s maxburst and maxpacket.

Signed-off-by: Akash Kumar <quic_akakum@quicinc.com>
---
Changes for v2:
Redefine logic for resizing tx fifos.

Changes for v1:
Added additional condition to allocate tx fifo for hs isoc eps,
keeping the other resize logic same.
---
 drivers/usb/dwc3/gadget.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 89fc690fdf34..49809a931104 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -778,15 +778,12 @@ static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep)
 
 	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
 
-	if ((dep->endpoint.maxburst > 1 &&
-	     usb_endpoint_xfer_bulk(dep->endpoint.desc)) ||
-	    usb_endpoint_xfer_isoc(dep->endpoint.desc))
-		num_fifos = 3;
-
-	if (dep->endpoint.maxburst > 6 &&
-	    (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
-	     usb_endpoint_xfer_isoc(dep->endpoint.desc)) && DWC3_IP_IS(DWC31))
-		num_fifos = dwc->tx_fifo_resize_max_num;
+	if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
+		num_fifos = min_t(unsigned int, dep->endpoint.maxburst + 1,
+				  dwc->tx_fifo_resize_max_num);
+	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
+		num_fifos = max_t(unsigned int, dep->endpoint.maxburst,
+				  usb_endpoint_maxp_mult(dep->endpoint.desc));
 
 	/* FIFO size for a single buffer */
 	fifo = dwc3_gadget_calc_tx_fifo_size(dwc, 1);
-- 
2.17.1

Re: [PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[Thinh Nguyen]

On Tue, Sep 03, 2024, Akash Kumar wrote:
> The current logic is rigid, setting num_fifos to fixed values:
> 
> 3 for any maxburst greater than 1.
> tx_fifo_resize_max_num for maxburst greater than 6.
> Additionally, it did not differentiate much between bulk and
> isochronous transfers, applying similar logic to both.
> 
> The new logic is more dynamic and tailored to the specific needs of
> bulk and isochronous transfers:
> 
> Bulk Transfers: Ensures that num_fifos is optimized by considering
> both the maxburst value and the maximum allowed number of FIFOs.
> 
> Isochronous Transfers: Ensures that num_fifos is sufficient by
> considering the maxburst value and the maximum packet multiplier.
> 
> This change aims to optimize the allocation of Tx FIFOs for both bulk
> and isochronous endpoints, potentially improving data transfer
> efficiency and overall performance.
> It also enhances support for all use cases, which can be tweaked
> with DT parameters and the endpoint’s maxburst and maxpacket.
> 
> Signed-off-by: Akash Kumar <quic_akakum@quicinc.com>
> ---
> Changes for v2:
> Redefine logic for resizing tx fifos.
> 
> Changes for v1:
> Added additional condition to allocate tx fifo for hs isoc eps,
> keeping the other resize logic same.
> ---
>  drivers/usb/dwc3/gadget.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 89fc690fdf34..49809a931104 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -778,15 +778,12 @@ static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep)
>  
>  	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
>  
> -	if ((dep->endpoint.maxburst > 1 &&
> -	     usb_endpoint_xfer_bulk(dep->endpoint.desc)) ||
> -	    usb_endpoint_xfer_isoc(dep->endpoint.desc))
> -		num_fifos = 3;
> -
> -	if (dep->endpoint.maxburst > 6 &&
> -	    (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
> -	     usb_endpoint_xfer_isoc(dep->endpoint.desc)) && DWC3_IP_IS(DWC31))
> -		num_fifos = dwc->tx_fifo_resize_max_num;
> +	if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
> +		num_fifos = min_t(unsigned int, dep->endpoint.maxburst + 1,
> +				  dwc->tx_fifo_resize_max_num);
> +	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
> +		num_fifos = max_t(unsigned int, dep->endpoint.maxburst,
> +				  usb_endpoint_maxp_mult(dep->endpoint.desc));

No. Don't mix usb_endpoint_maxp_mult with maxburst like this. Check base
on operating speed. Also, now you're ignoring tx_fifo_resize_max_num for
isoc.

BR,
Thinh

Re: [PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[AKASH KUMAR]

Hi Thinh,

On 9/4/2024 3:41 AM, Thinh Nguyen wrote:
> On Tue, Sep 03, 2024, Akash Kumar wrote:
>> The current logic is rigid, setting num_fifos to fixed values:
>>
>> 3 for any maxburst greater than 1.
>> tx_fifo_resize_max_num for maxburst greater than 6.
>> Additionally, it did not differentiate much between bulk and
>> isochronous transfers, applying similar logic to both.
>>
>> The new logic is more dynamic and tailored to the specific needs of
>> bulk and isochronous transfers:
>>
>> Bulk Transfers: Ensures that num_fifos is optimized by considering
>> both the maxburst value and the maximum allowed number of FIFOs.
>>
>> Isochronous Transfers: Ensures that num_fifos is sufficient by
>> considering the maxburst value and the maximum packet multiplier.
>>
>> This change aims to optimize the allocation of Tx FIFOs for both bulk
>> and isochronous endpoints, potentially improving data transfer
>> efficiency and overall performance.
>> It also enhances support for all use cases, which can be tweaked
>> with DT parameters and the endpoint’s maxburst and maxpacket.
>>
>> Signed-off-by: Akash Kumar <quic_akakum@quicinc.com>
>> ---
>> Changes for v2:
>> Redefine logic for resizing tx fifos.
>>
>> Changes for v1:
>> Added additional condition to allocate tx fifo for hs isoc eps,
>> keeping the other resize logic same.
>> ---
>>   drivers/usb/dwc3/gadget.c | 15 ++++++---------
>>   1 file changed, 6 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index 89fc690fdf34..49809a931104 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -778,15 +778,12 @@ static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep)
>>   
>>   	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
>>   
>> -	if ((dep->endpoint.maxburst > 1 &&
>> -	     usb_endpoint_xfer_bulk(dep->endpoint.desc)) ||
>> -	    usb_endpoint_xfer_isoc(dep->endpoint.desc))
>> -		num_fifos = 3;
>> -
>> -	if (dep->endpoint.maxburst > 6 &&
>> -	    (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
>> -	     usb_endpoint_xfer_isoc(dep->endpoint.desc)) && DWC3_IP_IS(DWC31))
>> -		num_fifos = dwc->tx_fifo_resize_max_num;
>> +	if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
>> +		num_fifos = min_t(unsigned int, dep->endpoint.maxburst + 1,
>> +				  dwc->tx_fifo_resize_max_num);
>> +	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
>> +		num_fifos = max_t(unsigned int, dep->endpoint.maxburst,
>> +				  usb_endpoint_maxp_mult(dep->endpoint.desc));
> No. Don't mix usb_endpoint_maxp_mult with maxburst like this. Check base
> on operating speed. Also, now you're ignoring tx_fifo_resize_max_num for
> isoc.
Sure will add separate check based on speed.

We have to support three versions of CAM support through same dt and image
SS/SS+ capable cam which needs 10k fifo
HS cams which needs 3K
multi UVC cams which needs 1k and 2k fifo

Putting any dependency with tx_fifo_resize_max_num, we can't achieve 1k 
and 10K,
it has to be decided by maxbursts itself which user can configure.
All uvc gadget applications supports configurable maxburst which they 
use while opening,
so it should be better for isoc eps to decide fifo based on maxbursts.

Thanks,
Akash

Re: [PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[Thinh Nguyen]

On Wed, Sep 04, 2024, AKASH KUMAR wrote:
> Hi Thinh,
> 
> On 9/4/2024 3:41 AM, Thinh Nguyen wrote:
> > On Tue, Sep 03, 2024, Akash Kumar wrote:
> > > The current logic is rigid, setting num_fifos to fixed values:
> > > 
> > > 3 for any maxburst greater than 1.
> > > tx_fifo_resize_max_num for maxburst greater than 6.
> > > Additionally, it did not differentiate much between bulk and
> > > isochronous transfers, applying similar logic to both.
> > > 
> > > The new logic is more dynamic and tailored to the specific needs of
> > > bulk and isochronous transfers:
> > > 
> > > Bulk Transfers: Ensures that num_fifos is optimized by considering
> > > both the maxburst value and the maximum allowed number of FIFOs.
> > > 
> > > Isochronous Transfers: Ensures that num_fifos is sufficient by
> > > considering the maxburst value and the maximum packet multiplier.
> > > 
> > > This change aims to optimize the allocation of Tx FIFOs for both bulk
> > > and isochronous endpoints, potentially improving data transfer
> > > efficiency and overall performance.
> > > It also enhances support for all use cases, which can be tweaked
> > > with DT parameters and the endpoint’s maxburst and maxpacket.
> > > 
> > > Signed-off-by: Akash Kumar <quic_akakum@quicinc.com>
> > > ---
> > > Changes for v2:
> > > Redefine logic for resizing tx fifos.
> > > 
> > > Changes for v1:
> > > Added additional condition to allocate tx fifo for hs isoc eps,
> > > keeping the other resize logic same.
> > > ---
> > >   drivers/usb/dwc3/gadget.c | 15 ++++++---------
> > >   1 file changed, 6 insertions(+), 9 deletions(-)
> > > 
> > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > > index 89fc690fdf34..49809a931104 100644
> > > --- a/drivers/usb/dwc3/gadget.c
> > > +++ b/drivers/usb/dwc3/gadget.c
> > > @@ -778,15 +778,12 @@ static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep)
> > >   	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
> > > -	if ((dep->endpoint.maxburst > 1 &&
> > > -	     usb_endpoint_xfer_bulk(dep->endpoint.desc)) ||
> > > -	    usb_endpoint_xfer_isoc(dep->endpoint.desc))
> > > -		num_fifos = 3;
> > > -
> > > -	if (dep->endpoint.maxburst > 6 &&
> > > -	    (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
> > > -	     usb_endpoint_xfer_isoc(dep->endpoint.desc)) && DWC3_IP_IS(DWC31))
> > > -		num_fifos = dwc->tx_fifo_resize_max_num;
> > > +	if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
> > > +		num_fifos = min_t(unsigned int, dep->endpoint.maxburst + 1,
> > > +				  dwc->tx_fifo_resize_max_num);
> > > +	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
> > > +		num_fifos = max_t(unsigned int, dep->endpoint.maxburst,
> > > +				  usb_endpoint_maxp_mult(dep->endpoint.desc));
> > No. Don't mix usb_endpoint_maxp_mult with maxburst like this. Check base
> > on operating speed. Also, now you're ignoring tx_fifo_resize_max_num for
> > isoc.
> Sure will add separate check based on speed.
> 
> We have to support three versions of CAM support through same dt and image
> SS/SS+ capable cam which needs 10k fifo
> HS cams which needs 3K
> multi UVC cams which needs 1k and 2k fifo
> 
> Putting any dependency with tx_fifo_resize_max_num, we can't achieve 1k and
> 10K,

That doesn't make sense. The tx_fifo_resize_max_num is a configurable
constraint through devicetree property. How can it not work?

> it has to be decided by maxbursts itself which user can configure.
> All uvc gadget applications supports configurable maxburst which they use
> while opening,
> so it should be better for isoc eps to decide fifo based on maxbursts.
> 

We should not just look at maxburst. It's only applicable to usb3
speeds. How the function driver configures maxp_mult* vs maxbursts is
independent. So let's keep the check separate base on speed for isoc.

Thanks,
Thinh

[*] Let's refer the mouthful "additional transaction opportunities" as
maxp_mult.

Re: [PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[AKASH KUMAR]

Hi Thinh,

On 9/5/2024 3:36 AM, Thinh Nguyen wrote:
> On Wed, Sep 04, 2024, AKASH KUMAR wrote:
>> Hi Thinh,
>>
>> On 9/4/2024 3:41 AM, Thinh Nguyen wrote:
>>> On Tue, Sep 03, 2024, Akash Kumar wrote:
>>>> The current logic is rigid, setting num_fifos to fixed values:
>>>>
>>>> 3 for any maxburst greater than 1.
>>>> tx_fifo_resize_max_num for maxburst greater than 6.
>>>> Additionally, it did not differentiate much between bulk and
>>>> isochronous transfers, applying similar logic to both.
>>>>
>>>> The new logic is more dynamic and tailored to the specific needs of
>>>> bulk and isochronous transfers:
>>>>
>>>> Bulk Transfers: Ensures that num_fifos is optimized by considering
>>>> both the maxburst value and the maximum allowed number of FIFOs.
>>>>
>>>> Isochronous Transfers: Ensures that num_fifos is sufficient by
>>>> considering the maxburst value and the maximum packet multiplier.
>>>>
>>>> This change aims to optimize the allocation of Tx FIFOs for both bulk
>>>> and isochronous endpoints, potentially improving data transfer
>>>> efficiency and overall performance.
>>>> It also enhances support for all use cases, which can be tweaked
>>>> with DT parameters and the endpoint’s maxburst and maxpacket.
>>>>
>>>> Signed-off-by: Akash Kumar <quic_akakum@quicinc.com>
>>>> ---
>>>> Changes for v2:
>>>> Redefine logic for resizing tx fifos.
>>>>
>>>> Changes for v1:
>>>> Added additional condition to allocate tx fifo for hs isoc eps,
>>>> keeping the other resize logic same.
>>>> ---
>>>>    drivers/usb/dwc3/gadget.c | 15 ++++++---------
>>>>    1 file changed, 6 insertions(+), 9 deletions(-)
>>>>
>>>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>>>> index 89fc690fdf34..49809a931104 100644
>>>> --- a/drivers/usb/dwc3/gadget.c
>>>> +++ b/drivers/usb/dwc3/gadget.c
>>>> @@ -778,15 +778,12 @@ static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep)
>>>>    	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
>>>> -	if ((dep->endpoint.maxburst > 1 &&
>>>> -	     usb_endpoint_xfer_bulk(dep->endpoint.desc)) ||
>>>> -	    usb_endpoint_xfer_isoc(dep->endpoint.desc))
>>>> -		num_fifos = 3;
>>>> -
>>>> -	if (dep->endpoint.maxburst > 6 &&
>>>> -	    (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
>>>> -	     usb_endpoint_xfer_isoc(dep->endpoint.desc)) && DWC3_IP_IS(DWC31))
>>>> -		num_fifos = dwc->tx_fifo_resize_max_num;
>>>> +	if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
>>>> +		num_fifos = min_t(unsigned int, dep->endpoint.maxburst + 1,
>>>> +				  dwc->tx_fifo_resize_max_num);
>>>> +	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
>>>> +		num_fifos = max_t(unsigned int, dep->endpoint.maxburst,
>>>> +				  usb_endpoint_maxp_mult(dep->endpoint.desc));
>>> No. Don't mix usb_endpoint_maxp_mult with maxburst like this. Check base
>>> on operating speed. Also, now you're ignoring tx_fifo_resize_max_num for
>>> isoc.
>> Sure will add separate check based on speed.
>>
>> We have to support three versions of CAM support through same dt and image
>> SS/SS+ capable cam which needs 10k fifo
>> HS cams which needs 3K
>> multi UVC cams which needs 1k and 2k fifo
>>
>> Putting any dependency with tx_fifo_resize_max_num, we can't achieve 1k and
>> 10K,
> That doesn't make sense. The tx_fifo_resize_max_num is a configurable
> constraint through devicetree property. How can it not work?
i have tested and i don't have any problem in adding constraint with HS 
but for SS
i need to set fifo size of 1K for 1 cam and 10k for other.
if i add any boundary with tx_fifo_resize_max_num (either max or min ) 
one of tx fifo size
either 1k or 10K i won't be able to set. So i request you allow to for 
 >=SS , to decide fifo
size based on maxburst only. i will be pusing patchset3 with that. 
please approve consideration this.
>> it has to be decided by maxbursts itself which user can configure.
>> All uvc gadget applications supports configurable maxburst which they use
>> while opening,
>> so it should be better for isoc eps to decide fifo based on maxbursts.
>>
> We should not just look at maxburst. It's only applicable to usb3
> speeds. How the function driver configures maxp_mult* vs maxbursts is
> independent. So let's keep the check separate base on speed for isoc.
>
> Thanks,
> Thinh
>
> [*] Let's refer the mouthful "additional transaction opportunities" as
> maxp_mult.

yes of course i will add separate check for maxp_mult in patchset3 for 
<=HS speed devices.

Thanks,
Akash

Re: [PATCH v2] usb: dwc3: gadget: Refine the logic for resizing Tx FIFOs

[Thinh Nguyen]

On Thu, Sep 05, 2024, AKASH KUMAR wrote:
> Hi Thinh,
> 
> On 9/5/2024 3:36 AM, Thinh Nguyen wrote:
> > On Wed, Sep 04, 2024, AKASH KUMAR wrote:
> > > Hi Thinh,
> > > 
> > > On 9/4/2024 3:41 AM, Thinh Nguyen wrote:
> > > > On Tue, Sep 03, 2024, Akash Kumar wrote:
> > > > > The current logic is rigid, setting num_fifos to fixed values:
> > > > > 
> > > > > 3 for any maxburst greater than 1.
> > > > > tx_fifo_resize_max_num for maxburst greater than 6.
> > > > > Additionally, it did not differentiate much between bulk and
> > > > > isochronous transfers, applying similar logic to both.
> > > > > 
> > > > > The new logic is more dynamic and tailored to the specific needs of
> > > > > bulk and isochronous transfers:
> > > > > 
> > > > > Bulk Transfers: Ensures that num_fifos is optimized by considering
> > > > > both the maxburst value and the maximum allowed number of FIFOs.
> > > > > 
> > > > > Isochronous Transfers: Ensures that num_fifos is sufficient by
> > > > > considering the maxburst value and the maximum packet multiplier.
> > > > > 
> > > > > This change aims to optimize the allocation of Tx FIFOs for both bulk
> > > > > and isochronous endpoints, potentially improving data transfer
> > > > > efficiency and overall performance.
> > > > > It also enhances support for all use cases, which can be tweaked
> > > > > with DT parameters and the endpoint’s maxburst and maxpacket.
> > > > > 
> > > > > Signed-off-by: Akash Kumar <quic_akakum@quicinc.com>
> > > > > ---
> > > > > Changes for v2:
> > > > > Redefine logic for resizing tx fifos.
> > > > > 
> > > > > Changes for v1:
> > > > > Added additional condition to allocate tx fifo for hs isoc eps,
> > > > > keeping the other resize logic same.
> > > > > ---
> > > > >    drivers/usb/dwc3/gadget.c | 15 ++++++---------
> > > > >    1 file changed, 6 insertions(+), 9 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> > > > > index 89fc690fdf34..49809a931104 100644
> > > > > --- a/drivers/usb/dwc3/gadget.c
> > > > > +++ b/drivers/usb/dwc3/gadget.c
> > > > > @@ -778,15 +778,12 @@ static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep)
> > > > >    	ram1_depth = DWC3_RAM1_DEPTH(dwc->hwparams.hwparams7);
> > > > > -	if ((dep->endpoint.maxburst > 1 &&
> > > > > -	     usb_endpoint_xfer_bulk(dep->endpoint.desc)) ||
> > > > > -	    usb_endpoint_xfer_isoc(dep->endpoint.desc))
> > > > > -		num_fifos = 3;
> > > > > -
> > > > > -	if (dep->endpoint.maxburst > 6 &&
> > > > > -	    (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
> > > > > -	     usb_endpoint_xfer_isoc(dep->endpoint.desc)) && DWC3_IP_IS(DWC31))
> > > > > -		num_fifos = dwc->tx_fifo_resize_max_num;
> > > > > +	if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
> > > > > +		num_fifos = min_t(unsigned int, dep->endpoint.maxburst + 1,
> > > > > +				  dwc->tx_fifo_resize_max_num);
> > > > > +	if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
> > > > > +		num_fifos = max_t(unsigned int, dep->endpoint.maxburst,
> > > > > +				  usb_endpoint_maxp_mult(dep->endpoint.desc));
> > > > No. Don't mix usb_endpoint_maxp_mult with maxburst like this. Check base
> > > > on operating speed. Also, now you're ignoring tx_fifo_resize_max_num for
> > > > isoc.
> > > Sure will add separate check based on speed.
> > > 
> > > We have to support three versions of CAM support through same dt and image
> > > SS/SS+ capable cam which needs 10k fifo
> > > HS cams which needs 3K
> > > multi UVC cams which needs 1k and 2k fifo
> > > 
> > > Putting any dependency with tx_fifo_resize_max_num, we can't achieve 1k and
> > > 10K,
> > That doesn't make sense. The tx_fifo_resize_max_num is a configurable
> > constraint through devicetree property. How can it not work?
> i have tested and i don't have any problem in adding constraint with HS but
> for SS
> i need to set fifo size of 1K for 1 cam and 10k for other.
> if i add any boundary with tx_fifo_resize_max_num (either max or min ) one
> of tx fifo size
> either 1k or 10K i won't be able to set. So i request you allow to for >=SS
> , to decide fifo
> size based on maxburst only. i will be pusing patchset3 with that. please
> approve consideration this.

I still don't understand. Did you try to increase the
tx_fifo_resize_max_num via devicetree property?

I don't want inconsistent behavior where tx_fifo_resize_max_num applies
to some but not others.

BR,
Thinh