On 4/14/14 4:11 PM, [email protected] wrote: > From: Dinh Nguyen <[email protected]> > > The dwc2 IP on the SOCFPGA cannot use the default HW configured > FIFO sizes. The total FIFO depth as read from GHWCFG3 reports 0x1f80 or 8064 > 32-bit words. But the GRXFSIZ, GNPTXFSIZ, and HPTXFSIZ register defaults > to 0x2000 or 8192 32-bit words. So the driver cannot just use the fifo sizes > as read from those registers. > > For platforms that face the same issue, this commits sets the RX, periodic TX, > and non-periodic TX fifo size to those that are recommended v2.93a spec for > the DWC2 IP. Implements Method #2 from the Synopsys v2.93a spec for the DWC2. > > Signed-off-by: Dinh Nguyen <[email protected]> > Acked-by: Paul Zimmerman <[email protected]> > Reviewed-by: Felipe Balbi <[email protected]> > --- > v5: > - Fix build error around dev_err() > > v4: > - Fix comment style errors > - Use comment suggestion from Felipe to clearly commmunicate invalid fifo > sizes > - Removed useless comment > > v3: > - Address comments from Felipe > - Used Method 2 as recommended by Synopsys to high-bandwidth endpoints. > > v2: > - Fix coding style with braces around both if() branches > --- > drivers/usb/dwc2/core.c | 68 > +++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 68 insertions(+) > > diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c > index 1d12988..27d2c9b 100644 > --- a/drivers/usb/dwc2/core.c > +++ b/drivers/usb/dwc2/core.c > @@ -507,6 +507,72 @@ void dwc2_disable_host_interrupts(struct dwc2_hsotg > *hsotg) > writel(intmsk, hsotg->regs + GINTMSK); > } > > +/* > + * dwc2_calculate_dynamic_fifo() - Calculates the default fifo size > + * For system that have a total fifo depth that is smaller than the default > + * RX + TX fifo size. > + * > + * @hsotg: Programming view of DWC_otg controller > + */ > +static void dwc2_calculate_dynamic_fifo(struct dwc2_hsotg *hsotg) > +{ > + struct dwc2_core_params *params = hsotg->core_params; > + struct dwc2_hw_params *hw = &hsotg->hw_params; > + u32 rxfsiz, nptxfsiz, ptxfsiz, total_fifo_size; > + > + total_fifo_size = hw->total_fifo_size; > + rxfsiz = params->host_rx_fifo_size; > + nptxfsiz = params->host_nperio_tx_fifo_size; > + ptxfsiz = params->host_perio_tx_fifo_size; > + > + /* > + * Will use Method 2 defined in the DWC2 spec: minimum FIFO depth > + * allocation with support for high bandwidth endpoints. Synopsys > + * defines MPS(Max Packet size) for a periodic EP=1024, and for > + * non-periodic as 512. > + */ > + if (total_fifo_size < (rxfsiz + nptxfsiz + ptxfsiz)) { > + /* > + * For Buffer DMA mode/Scatter Gather DMA mode > + * 2 * ((Largest Packet size / 4) + 1 + 1) + n > + * with n = number of host channel. > + * 2 * ((1024/4) + 2) = 516 > + */ > + rxfsiz = 516 + hw->host_channels; > + > + /* > + * min non-periodic tx fifo depth > + * 2 * (largest non-periodic USB packet used / 4) > + * 2 * (512/4) = 256 > + */ > + nptxfsiz = 256; > + > + /* > + * min periodic tx fifo depth > + * (largest packet size*MC)/4 > + * (1024 * 3)/4 = 768 > + */ > + ptxfsiz = 768; > + > + params->host_rx_fifo_size = rxfsiz; > + params->host_nperio_tx_fifo_size = nptxfsiz; > + params->host_perio_tx_fifo_size = ptxfsiz; > + } > + > + /* > + * If the summation of RX, NPTX and PTX fifo sizes is still > + * bigger than the total_fifo_size, then we have a problem. > + * > + * We won't be able to allocate as many endpoints. Right now, > + * we're just printing an error message, but ideally this FIFO > + * allocation algorithm would be improved in the future. > + * > + * FIXME improve this FIFO allocation algorithm. > + */ > + if (unlikely(total_fifo_size < (rxfsiz + nptxfsiz + ptxfsiz))) > + dev_err(hsotg->dev, "invalid fifo sizes\n"); > +} > + > static void dwc2_config_fifos(struct dwc2_hsotg *hsotg) > { > struct dwc2_core_params *params = hsotg->core_params; > @@ -515,6 +581,8 @@ static void dwc2_config_fifos(struct dwc2_hsotg *hsotg) > if (!params->enable_dynamic_fifo) > return; > > + dwc2_calculate_dynamic_fifo(hsotg); > + > /* Rx FIFO */ > grxfsiz = readl(hsotg->regs + GRXFSIZ); > dev_dbg(hsotg->dev, "initial grxfsiz=%08x\n", grxfsiz); Hi Greg,
If you're ok with this patch, can you please apply this to usb-next? Thanks, Dinh -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
