diff options
| author | Wesley Cheng <wcheng@codeaurora.org> | 2021-07-10 02:13:12 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-12 09:37:26 +0200 |
| commit | 9f607a309fbe95fc1f77acce5af70766a7142537 (patch) | |
| tree | ba69cbac920359c83384bc030f11999d2e274c95 /drivers/usb/dwc3/core.c | |
| parent | 7adf9e3adc398e5d5b7af91e5fdfafa70e86dd36 (diff) | |
usb: dwc3: Resize TX FIFOs to meet EP bursting requirements
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@codeaurora.org>
Link: https://lore.kernel.org/r/1625908395-5498-4-git-send-email-wcheng@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/dwc3/core.c')
| -rw-r--r-- | drivers/usb/dwc3/core.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index ba74ad7f6995..b194aecd2202 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); dwc->disable_scramble_quirk = device_property_read_bool(dev, "snps,disable_scramble_quirk"); @@ -1390,6 +1403,8 @@ static void dwc3_get_properties(struct dwc3 *dwc) dwc->tx_max_burst_prd = tx_max_burst_prd; dwc->imod_interval = 0; + + dwc->tx_fifo_resize_max_num = tx_fifo_resize_max_num; } /* check whether the core supports IMOD */ |