On Wed, Jul 14, 2021 at 12:30:07AM -0700, Wesley Cheng wrote: > > > On 7/13/2021 11:40 PM, Felipe Balbi wrote: > > > > Hi, > > > > Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> writes: > >>> Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx> writes: > >>>> Wesley Cheng wrote: > >>>>> Some devices have USB compositions which may require multiple endpoints > >>>>> that support EP bursting. HW defined TX FIFO sizes may not always be > >>>>> sufficient for these compositions. By utilizing flexible TX FIFO > >>>>> allocation, this allows for endpoints to request the required FIFO depth to > >>>>> achieve higher bandwidth. With some higher bMaxBurst configurations, using > >>>>> a larger TX FIFO size results in better TX throughput. > >>>>> > >>>>> By introducing the check_config() callback, the resizing logic can fetch > >>>>> the maximum number of endpoints used in the USB composition (can contain > >>>>> multiple configurations), which helps ensure that the resizing logic can > >>>>> fulfill the configuration(s), or return an error to the gadget layer > >>>>> otherwise during bind time. > >>>>> > >>>>> Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx> > >>>>> --- > >>>>> drivers/usb/dwc3/core.c | 15 +++ > >>>>> drivers/usb/dwc3/core.h | 16 ++++ > >>>>> drivers/usb/dwc3/ep0.c | 2 + > >>>>> drivers/usb/dwc3/gadget.c | 232 ++++++++++++++++++++++++++++++++++++++++++++++ > >>>>> 4 files changed, 265 insertions(+) > >>>>> > >>>>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > >>>>> index ba74ad7..b194aecd 100644 > >>>>> --- a/drivers/usb/dwc3/core.c > >>>>> +++ b/drivers/usb/dwc3/core.c > >>>>> @@ -1267,6 +1267,7 @@ static void dwc3_get_properties(struct dwc3 *dwc) > >>>>> u8 rx_max_burst_prd; > >>>>> u8 tx_thr_num_pkt_prd; > >>>>> u8 tx_max_burst_prd; > >>>>> + u8 tx_fifo_resize_max_num; > >>>>> const char *usb_psy_name; > >>>>> int ret; > >>>>> > >>>>> @@ -1282,6 +1283,13 @@ static void dwc3_get_properties(struct dwc3 *dwc) > >>>>> */ > >>>>> hird_threshold = 12; > >>>>> > >>>>> + /* > >>>>> + * default to a TXFIFO size large enough to fit 6 max packets. This > >>>>> + * allows for systems with larger bus latencies to have some headroom > >>>>> + * for endpoints that have a large bMaxBurst value. > >>>>> + */ > >>>>> + tx_fifo_resize_max_num = 6; > >>>>> + > >>>>> dwc->maximum_speed = usb_get_maximum_speed(dev); > >>>>> dwc->max_ssp_rate = usb_get_maximum_ssp_rate(dev); > >>>>> dwc->dr_mode = usb_get_dr_mode(dev); > >>>>> @@ -1325,6 +1333,11 @@ static void dwc3_get_properties(struct dwc3 *dwc) > >>>>> &tx_thr_num_pkt_prd); > >>>>> device_property_read_u8(dev, "snps,tx-max-burst-prd", > >>>>> &tx_max_burst_prd); > >>>>> + dwc->do_fifo_resize = device_property_read_bool(dev, > >>>>> + "tx-fifo-resize"); > >>>>> + if (dwc->do_fifo_resize) > >>>>> + device_property_read_u8(dev, "tx-fifo-max-num", > >>>>> + &tx_fifo_resize_max_num); > >>>> > >>>> Why is this check here? The dwc->tx_fifo_resize_max_num should store > >>>> whatever property the user sets. Whether the driver wants to use this > >>> > >>> Ack! > >>> > >>>> property should depend on "dwc->do_fifo_resize". Also why don't we have > >>>> "snps," prefix to be consistent with the other properties? > >>> > >>> Ack! > >>> > >>>> Can we enforce to a single property? If the designer wants to enable > >>>> this feature, he/she can to provide the tx-fifo-max-num. This would > >>>> simplify the driver a bit. Since this is to optimize for performance, > >>>> the user should know/want/test the specific value if they want to set > >>>> for their setup and not hoping that the default setting not break their > >>>> setup. So we can remove the "do_fifo_resize" property and just check > >>>> whether tx_fifo_resize_max_num is set. > >>> > >>> Ack! > >>> > >>> All very valid points :-) > >>> > > Hi Thinh/Felipe, > > >> > >> Looks like this series already landed in Greg's testing branch. Not sure > >> how we usually handle this to address some of our concerns. Add fix > >> patches on top of Greg's testing branch? > > > > yup, no choice anymore :-( > > > > Let me review your feedback, which had some good points. We can add a > change addressing everything on top of what is merged on Greg's branch. Any hint as to when these fixups will be sent? thanks, greg k-h
