| Message ID | 1423253720-2785-1-git-send-email-m-karicheri2@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Fri, Feb 06, 2015 at 03:15:20PM -0500, Murali Karicheri wrote: > diff --git a/drivers/of/device.c b/drivers/of/device.c > index 314c8a9..44209fa 100644 > --- a/drivers/of/device.c > +++ b/drivers/of/device.c > @@ -83,17 +83,18 @@ int of_device_add(struct platform_device *ofdev) > */ > void of_dma_configure(struct device *dev, struct device_node *np) > { > - u64 dma_addr, paddr, size; > + u64 dma_addr = 0, paddr, size; > int ret; > bool coherent; > - unsigned long offset; > + unsigned long offset = 0; > struct iommu_ops *iommu; > > /* > * Set default dma-mask to 32 bit. Drivers are expected to setup > * the correct supported dma_mask. > */ > - dev->coherent_dma_mask = DMA_BIT_MASK(32); > + if (!dev->coherent_dma_mask) > + dev->coherent_dma_mask = DMA_BIT_MASK(32); > > /* > * Set it to coherent_dma_mask by default if the architecture > @@ -102,11 +103,14 @@ void of_dma_configure(struct device *dev, struct device_node *np) > if (!dev->dma_mask) > dev->dma_mask = &dev->coherent_dma_mask; > > + /* > + * Set default size to cover the 32-bit. Drivers are expected to setup > + * the correct size and dma_mask. > + */ Nitpick: drivers don't set up the size, just the mask. We read the size from DT. > + size = 1ULL << 32; > + > ret = of_dma_get_range(np, &dma_addr, &paddr, &size); > - if (ret < 0) { > - dma_addr = offset = 0; > - size = dev->coherent_dma_mask + 1; Do you assume that, on error, of_dma_get_range() does not touch any of the dma_addr/paddr/size? It looks safer to me to leave it as the original. > - } else { > + if (!ret) { > offset = PFN_DOWN(paddr - dma_addr); > > /* > @@ -128,6 +132,15 @@ void of_dma_configure(struct device *dev, struct device_node *np) > > dev->dma_pfn_offset = offset; > > + /* > + * Limit coherent and dma mask based on size and default mask > + * set by the driver. > + */ > + dev->coherent_dma_mask = min(dev->coherent_dma_mask, > + DMA_BIT_MASK(ilog2(dma_addr + size))); Do we need to cover the case where size is incorrectly set to 0 in the DT? At least some warning and leaving the mask unchanged. > + *dev->dma_mask = min((*dev->dma_mask), > + DMA_BIT_MASK(ilog2(dma_addr + size))); > + > coherent = of_dma_is_coherent(np); > dev_dbg(dev, "device is%sdma coherent\n", > coherent ? " " : " not ");
On 02/09/2015 06:27 AM, Catalin Marinas wrote: > On Fri, Feb 06, 2015 at 03:15:20PM -0500, Murali Karicheri wrote: >> diff --git a/drivers/of/device.c b/drivers/of/device.c >> index 314c8a9..44209fa 100644 >> --- a/drivers/of/device.c >> +++ b/drivers/of/device.c >> @@ -83,17 +83,18 @@ int of_device_add(struct platform_device *ofdev) >> */ >> void of_dma_configure(struct device *dev, struct device_node *np) >> { >> - u64 dma_addr, paddr, size; >> + u64 dma_addr = 0, paddr, size; >> int ret; >> bool coherent; >> - unsigned long offset; >> + unsigned long offset = 0; >> struct iommu_ops *iommu; >> >> /* >> * Set default dma-mask to 32 bit. Drivers are expected to setup >> * the correct supported dma_mask. >> */ >> - dev->coherent_dma_mask = DMA_BIT_MASK(32); >> + if (!dev->coherent_dma_mask) >> + dev->coherent_dma_mask = DMA_BIT_MASK(32); >> >> /* >> * Set it to coherent_dma_mask by default if the architecture >> @@ -102,11 +103,14 @@ void of_dma_configure(struct device *dev, struct device_node *np) >> if (!dev->dma_mask) >> dev->dma_mask =&dev->coherent_dma_mask; >> >> + /* >> + * Set default size to cover the 32-bit. Drivers are expected to setup >> + * the correct size and dma_mask. >> + */ > > Nitpick: drivers don't set up the size, just the mask. We read the size > from DT. Not sure how this came, I will update this. > >> + size = 1ULL<< 32; >> + >> ret = of_dma_get_range(np,&dma_addr,&paddr,&size); >> - if (ret< 0) { >> - dma_addr = offset = 0; >> - size = dev->coherent_dma_mask + 1; > > Do you assume that, on error, of_dma_get_range() does not touch any of > the dma_addr/paddr/size? It looks safer to me to leave it as the > original. I think dma_addr and paddr is both modified on error. So this change can't be done. I will revert the logic back to original. > >> - } else { >> + if (!ret) { >> offset = PFN_DOWN(paddr - dma_addr); >> >> /* >> @@ -128,6 +132,15 @@ void of_dma_configure(struct device *dev, struct device_node *np) >> >> dev->dma_pfn_offset = offset; >> >> + /* >> + * Limit coherent and dma mask based on size and default mask >> + * set by the driver. >> + */ >> + dev->coherent_dma_mask = min(dev->coherent_dma_mask, >> + DMA_BIT_MASK(ilog2(dma_addr + size))); > > Do we need to cover the case where size is incorrectly set to 0 in the > DT? At least some warning and leaving the mask unchanged. The previous series already warn and return if the size is incorrect (Patch v6 3/7) and leave the dma mask unchanged. So we don't have to do anything in this patch. I will fix the above and re-send. > >> + *dev->dma_mask = min((*dev->dma_mask), >> + DMA_BIT_MASK(ilog2(dma_addr + size))); >> + >> coherent = of_dma_is_coherent(np); >> dev_dbg(dev, "device is%sdma coherent\n", >> coherent ? " " : " not "); >
diff --git a/drivers/of/device.c b/drivers/of/device.c index 314c8a9..44209fa 100644 --- a/drivers/of/device.c +++ b/drivers/of/device.c @@ -83,17 +83,18 @@ int of_device_add(struct platform_device *ofdev) */ void of_dma_configure(struct device *dev, struct device_node *np) { - u64 dma_addr, paddr, size; + u64 dma_addr = 0, paddr, size; int ret; bool coherent; - unsigned long offset; + unsigned long offset = 0; struct iommu_ops *iommu; /* * Set default dma-mask to 32 bit. Drivers are expected to setup * the correct supported dma_mask. */ - dev->coherent_dma_mask = DMA_BIT_MASK(32); + if (!dev->coherent_dma_mask) + dev->coherent_dma_mask = DMA_BIT_MASK(32); /* * Set it to coherent_dma_mask by default if the architecture @@ -102,11 +103,14 @@ void of_dma_configure(struct device *dev, struct device_node *np) if (!dev->dma_mask) dev->dma_mask = &dev->coherent_dma_mask; + /* + * Set default size to cover the 32-bit. Drivers are expected to setup + * the correct size and dma_mask. + */ + size = 1ULL << 32; + ret = of_dma_get_range(np, &dma_addr, &paddr, &size); - if (ret < 0) { - dma_addr = offset = 0; - size = dev->coherent_dma_mask + 1; - } else { + if (!ret) { offset = PFN_DOWN(paddr - dma_addr); /* @@ -128,6 +132,15 @@ void of_dma_configure(struct device *dev, struct device_node *np) dev->dma_pfn_offset = offset; + /* + * Limit coherent and dma mask based on size and default mask + * set by the driver. + */ + dev->coherent_dma_mask = min(dev->coherent_dma_mask, + DMA_BIT_MASK(ilog2(dma_addr + size))); + *dev->dma_mask = min((*dev->dma_mask), + DMA_BIT_MASK(ilog2(dma_addr + size))); + coherent = of_dma_is_coherent(np); dev_dbg(dev, "device is%sdma coherent\n", coherent ? " " : " not ");
This patch update of_dma_configure() API to calculate the masks (dma_mask and coherent_dma_mask) based on the dma-range values set in DT for the device. Also limit the mask to lower of the default mask and mask calculated. Cc: Joerg Roedel <joro@8bytes.org> Cc: Grant Likely <grant.likely@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Signed-off-by: Murali Karicheri <m-karicheri2@ti.com> --- drivers/of/device.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-)