On Sat, Sep 28, 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 updated logic is more flexible and specifically designed to meet
> the unique requirements of both bulk and isochronous transfers. We
> have made every effort to satisfy all needs and requirements,
> verified on our specific platform and application.
>
> The updated logic is more flexible and specifically designed to meet
> the unique requirements of both bulk and isochronous transfers. We
> have made every effort to satisfy all needs and requirements, verified
> on our specific platform and application.
Was there a copy-and-paste issue with the above paragraph?
>
> Bulk Transfers: Ensures that num_fifos is optimized by considering both
> the maxburst and DT property tx_fifo_resize_max_num for super speed and
> above. For high-speed and below bulk endpoints, a 2K TxFIFO allocation
> is used to meet efficient data transfer needs, considering
> FIFO-constrained platforms.
>
> Isochronous Transfers: Ensures that num_fifos is sufficient by considering
> the maximum packet multiplier for HS and maxburst for SS, along with a
> constraint with the DT property tx_fifo_resize_max_num.
>
> 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 v5:
> Update Calculation for HS and below bulk and isoc eps based on
> suggestion and fixed at 2k for bulk eps considering fifo
> constrained platforms.
>
> Changes for v4:
> Updated commit message as per review comments to clarify that it has
> been tested on specific platforms only and tried best to match all
> expectations.
>
> Changes for v3:
> Redefine logic for resizing tx fifos,added check based on operating
> speed and used maxp for HS and maxburst for SS and defined max
> allocation based on dt property.
>
> Changes for v2:
> Redefine logic for resizing tx fifos, handled fifo based on minimum
> of maxp and maxburts.
>
> 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 | 20 +++++++++++++-------
> 1 file changed, 13 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 291bc549935b..035d49155d57 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -771,15 +771,21 @@ 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 (dwc->gadget->speed <= USB_SPEED_HIGH) {
> + if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
> + num_fifos = 2;
> + if (usb_endpoint_xfer_isoc(dep->endpoint.desc))
> + num_fifos = min_t(unsigned int,
> + usb_endpoint_maxp_mult(dep->endpoint.desc) + 1,
> + dwc->tx_fifo_resize_max_num);
> + }
>
> - if (dep->endpoint.maxburst > 6 &&
> + if (dwc->gadget->speed > USB_SPEED_HIGH &&
> (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;
> + usb_endpoint_xfer_isoc(dep->endpoint.desc)))
> + num_fifos = min_t(unsigned int,
> + dep->endpoint.maxburst,
> + dwc->tx_fifo_resize_max_num);
>
Do you have a default value for other endpoints?
Perhaps we can do something like this? What do you think?
num_fifos = 1;
switch (dwc->gadget->speed) {
case USB_SPEED_SUPER_PLUS:
case USB_SPEED_SUPER:
if (usb_endpoint_xfer_bulk(dep->endpoint.desc) ||
usb_endpoint_xfer_isoc(dep->endpoint.desc))
num_fifos = min_t(unsigned int,
dep->endpoint.maxburst,
dwc->tx_fifo_resize_max_num);
break;
case USB_SPEED_HIGH:
if (usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
num_fifos = min_t(unsigned int,
usb_endpoint_maxp_mult(dep->endpoint.desc) + 1,
dwc->tx_fifo_resize_max_num);
break;
}
fallthrough;
case USB_SPEED_FULL:
if (usb_endpoint_xfer_bulk(dep->endpoint.desc))
num_fifos = 2;
break;
default:
break;
}
Thanks,
Thinh
> /* FIFO size for a single buffer */
> fifo = dwc3_gadget_calc_tx_fifo_size(dwc, 1);
> --
> 2.17.1
>
