On Wed, Jul 14, 2021 at 03:10:25AM +0000, Thinh Nguyen wrote: > Felipe Balbi wrote: > > > > Hi, > > > > 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 :-) > > > > 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? Yes please send patches on top of this series. thanks, greg k-h
