On 06/06/2017 03:42 PM, Philipp Tomsich wrote: > For LP64 build w/ GCC 6.3, the handling of the ep->dma_buf variable > when (truncating and) writing into the controller's registers is > unsafe and triggers the following compiler warning (thus failing by > buildman tests): > ../drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c: In function 'setdma_rx': > ../drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c:116:9: warning: cast from > pointer to integer of different size [-Wpointer-to-int-cast] > writel((unsigned int) ep->dma_buf, ®->out_endp[ep_num].doepdma); > ^ > > This change fixes the warning and makes the code a bit more robust by > doing the following: > - we check whether ep->dma_buf can be safely truncated to 32 bits > (i.e. whether dma_buf is the same value when masked to 32 bits) and > emit an error message if that is not the case > - we cast to a uintptr_t and let the writel macro truncate the > uintptr_t (potentially a 64bit value) to 32bits > > Signed-off-by: Philipp Tomsich <[email protected]> > > --- > > Changes in v2: > - (new patch) fix warnings and add some robustness for the truncation > of ep->dma_buf in dwc2-otg for LP64 builds to fix a buildman failure > for u-boot-rockchip/master@2b19b2f > > drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c > b/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c > index 0d6d2fb..f5c926c 100644 > --- a/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c > +++ b/drivers/usb/gadget/dwc2_udc_otg_xfer_dma.c > @@ -113,7 +113,11 @@ static int setdma_rx(struct dwc2_ep *ep, struct > dwc2_request *req) > invalidate_dcache_range((unsigned long) ep->dma_buf, > (unsigned long) ep->dma_buf + ep->len); > > - writel((unsigned int) ep->dma_buf, ®->out_endp[ep_num].doepdma); > + /* ensure that ep->dma_buf fits into 32 bits */ > + if (((uintptr_t)ep->dma_buf & 0xffffffff) != (uintptr_t)ep->dma_buf) > + error("ep->dma_buf does not fit into a 32 bits");
You print an error, but still continue with the function ? That'll probably lead to a crash, you should rather abort. In fact, I suspect you can use bounce-buffer to assure the dma buffer is in 32bit space. > + writel((uintptr_t)ep->dma_buf, ®->out_endp[ep_num].doepdma); > writel(DOEPT_SIZ_PKT_CNT(pktcnt) | DOEPT_SIZ_XFER_SIZE(length), > ®->out_endp[ep_num].doeptsiz); > writel(DEPCTL_EPENA|DEPCTL_CNAK|ctrl, ®->out_endp[ep_num].doepctl); > -- Best regards, Marek Vasut _______________________________________________ U-Boot mailing list [email protected] https://lists.denx.de/listinfo/u-boot
