On Wed, Sep 04, 2024, AKASH KUMAR wrote:i have tested and i don't have any problem in adding constraint with HS but for SS
Hi Thinh,That doesn't make sense. The tx_fifo_resize_max_num is a configurable
On 9/4/2024 3:41 AM, Thinh Nguyen wrote:
On Tue, Sep 03, 2024, Akash Kumar wrote:Sure will add separate check based on speed.
The current logic is rigid, setting num_fifos to fixed values:No. Don't mix usb_endpoint_maxp_mult with maxburst like this. Check base
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@xxxxxxxxxxx>
---
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));
on operating speed. Also, now you're ignoring tx_fifo_resize_max_num for
isoc.
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,
constraint through devicetree property. How can it not work?
it has to be decided by maxbursts itself which user can configure.We should not just look at maxburst. It's only applicable to usb3
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.
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.