| Message ID | 1457594332-7490-2-git-send-email-tqnguyen@apm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, "Thang Q. Nguyen" <tqnguyen@apm.com> writes: > From: "Thang Q. Nguyen" <tqnguyen@apm.com> > > Add 64-bit DMA operation support to the USB DWC3 driver. > First attempt to set the coherent DMA mask for 64-bit DMA. > If that failed, attempt again with 32-bit DMA. > > Changes from v2: > - None. > > Changes from v1: > - Remove WARN_ON if dma_mask is NULL these changes lines should be between the tearline (---) and diffstat below. > Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com> > --- > drivers/usb/dwc3/core.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index de5e01f..2479c24 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev) > dwc->mem = mem; > dwc->dev = dev; > > + /* Try to set 64-bit DMA first */ > + if (!pdev->dev.dma_mask) > + /* Platform did not initialize dma_mask */ > + ret = dma_coerce_mask_and_coherent(&pdev->dev, > + DMA_BIT_MASK(64)); > + else > + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); > + > + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */ > + if (ret) { > + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); > + if (ret) > + return ret; > + } Also, why is it so that you need this now ? glue layers are copying dma mask from parent device and that should be set properly. This really shouldn't be necessary in dwc3-core; it would mean that glue layer didn't set this device up properly.
Hi Balbi, If CONFIG_DMA_CMA=y, dma mask is set properly. The issue just happen when CONFIG_DMA_CMA is not set. In this case, dma mask is not set and we need this code to check if dma mask should be manually set to 32 or 64. ---- Thang On Wed, Mar 30, 2016 at 8:09 PM, Felipe Balbi <felipe.balbi@linux.intel.com> wrote: > > Hi, > > "Thang Q. Nguyen" <tqnguyen@apm.com> writes: >> From: "Thang Q. Nguyen" <tqnguyen@apm.com> >> >> Add 64-bit DMA operation support to the USB DWC3 driver. >> First attempt to set the coherent DMA mask for 64-bit DMA. >> If that failed, attempt again with 32-bit DMA. >> >> Changes from v2: >> - None. >> >> Changes from v1: >> - Remove WARN_ON if dma_mask is NULL > > these changes lines should be between the tearline (---) and diffstat > below. > >> Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com> >> --- >> drivers/usb/dwc3/core.c | 15 +++++++++++++++ >> 1 file changed, 15 insertions(+) >> >> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c >> index de5e01f..2479c24 100644 >> --- a/drivers/usb/dwc3/core.c >> +++ b/drivers/usb/dwc3/core.c >> @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev) >> dwc->mem = mem; >> dwc->dev = dev; >> >> + /* Try to set 64-bit DMA first */ >> + if (!pdev->dev.dma_mask) >> + /* Platform did not initialize dma_mask */ >> + ret = dma_coerce_mask_and_coherent(&pdev->dev, >> + DMA_BIT_MASK(64)); >> + else >> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); >> + >> + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */ >> + if (ret) { >> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); >> + if (ret) >> + return ret; >> + } > > Also, why is it so that you need this now ? glue layers are copying dma > mask from parent device and that should be set properly. This really > shouldn't be necessary in dwc3-core; it would mean that glue layer > didn't set this device up properly. > > -- > balbi
Hi, (please don't top-post) "Thang Q. Nguyen" <tqnguyen@apm.com> writes: > Hi Balbi, > If CONFIG_DMA_CMA=y, dma mask is set properly. The issue just happen > when CONFIG_DMA_CMA is not set. In this case, dma mask is not set and > we need this code to check if dma mask should be manually set to 32 or > 64. Can you point me to the code which has this conditional ? Why would DMA_CMA=n mean that dma_mask isn't initialized ? According to DMA_CMA's help text (see below) that's supposed to allow drivers to *allocate* large contiguous buffers, but that's not the case here. config DMA_CMA bool "DMA Contiguous Memory Allocator" depends on HAVE_DMA_CONTIGUOUS && CMA help This enables the Contiguous Memory Allocator which allows drivers to allocate big physically-contiguous blocks of memory for use with hardware components that do not support I/O map nor scatter-gather. You can disable CMA by specifying "cma=0" on the kernel's command line. For more information see <include/linux/dma-contiguous.h>. If unsure, say "n". > > ---- > Thang > > On Wed, Mar 30, 2016 at 8:09 PM, Felipe Balbi > <felipe.balbi@linux.intel.com> wrote: >> >> Hi, >> >> "Thang Q. Nguyen" <tqnguyen@apm.com> writes: >>> From: "Thang Q. Nguyen" <tqnguyen@apm.com> >>> >>> Add 64-bit DMA operation support to the USB DWC3 driver. >>> First attempt to set the coherent DMA mask for 64-bit DMA. >>> If that failed, attempt again with 32-bit DMA. >>> >>> Changes from v2: >>> - None. >>> >>> Changes from v1: >>> - Remove WARN_ON if dma_mask is NULL >> >> these changes lines should be between the tearline (---) and diffstat >> below. >> >>> Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com> >>> --- >>> drivers/usb/dwc3/core.c | 15 +++++++++++++++ >>> 1 file changed, 15 insertions(+) >>> >>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c >>> index de5e01f..2479c24 100644 >>> --- a/drivers/usb/dwc3/core.c >>> +++ b/drivers/usb/dwc3/core.c >>> @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev) >>> dwc->mem = mem; >>> dwc->dev = dev; >>> >>> + /* Try to set 64-bit DMA first */ >>> + if (!pdev->dev.dma_mask) >>> + /* Platform did not initialize dma_mask */ >>> + ret = dma_coerce_mask_and_coherent(&pdev->dev, >>> + DMA_BIT_MASK(64)); >>> + else >>> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); >>> + >>> + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */ >>> + if (ret) { >>> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); >>> + if (ret) >>> + return ret; >>> + } >> >> Also, why is it so that you need this now ? glue layers are copying dma >> mask from parent device and that should be set properly. This really >> shouldn't be necessary in dwc3-core; it would mean that glue layer >> didn't set this device up properly. >> >> -- >> balbi > > > > -- > > Thang Q. Nguyen | Staff SW Eng. > > C: +849.7684.7606 | O: +848.3770.0640 > > F: +848.3770.0641 | tqnguyen@apm.com
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index de5e01f..2479c24 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -831,6 +831,21 @@ static int dwc3_probe(struct platform_device *pdev) dwc->mem = mem; dwc->dev = dev; + /* Try to set 64-bit DMA first */ + if (!pdev->dev.dma_mask) + /* Platform did not initialize dma_mask */ + ret = dma_coerce_mask_and_coherent(&pdev->dev, + DMA_BIT_MASK(64)); + else + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + + /* If seting 64-bit DMA mask fails, fall back to 32-bit DMA mask */ + if (ret) { + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (ret) + return ret; + } + res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (!res) { dev_err(dev, "missing IRQ\n");