Messages in this thread | | | Date | Fri, 6 Feb 2015 15:26:55 -0500 | From | Murali Karicheri <> | Subject | Re: [PATCH v6 3/7] of: fix size when dma-range is not used |
| |
On 02/06/2015 10:12 AM, Catalin Marinas wrote: > On Fri, Feb 06, 2015 at 02:54:23PM +0000, Murali Karicheri wrote: >> On 02/06/2015 09:38 AM, Catalin Marinas wrote: >>> On Thu, Feb 05, 2015 at 09:52:55PM +0000, Murali Karicheri wrote: >>>> Fix the dma-range size when the DT attribute is missing. i.e set size to >>>> dev->coherent_dma_mask + 1 instead of dev->coherent_dma_mask. Also add >>>> code to check invalid values of size configured in DT and log error. >>>> >>>> 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 | 17 ++++++++++++++++- >>>> 1 file changed, 16 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/of/device.c b/drivers/of/device.c >>>> index 2de320d..314c8a9 100644 >>>> --- a/drivers/of/device.c >>>> +++ b/drivers/of/device.c >>>> @@ -105,9 +105,24 @@ void of_dma_configure(struct device *dev, struct device_node *np) >>>> ret = of_dma_get_range(np,&dma_addr,&paddr,&size); >>>> if (ret< 0) { >>>> dma_addr = offset = 0; >>>> - size = dev->coherent_dma_mask; >>>> + size = dev->coherent_dma_mask + 1; >>>> } else { >>>> offset = PFN_DOWN(paddr - dma_addr); >>>> + >>>> + /* >>>> + * Add a work around to treat the size as mask + 1 in case >>>> + * it is defined in DT as a mask. >>>> + */ >>>> + if (size& 1) { >>>> + dev_warn(dev, "Invalid size 0x%llx for dma-range\n", >>>> + size); >>>> + size = size + 1; >>>> + } >>>> + >>>> + if (!size) { >>>> + dev_err(dev, "Adjusted size 0x%llx invalid\n", size); >>>> + return; >>>> + } >>> >>> Would it make sense to set coherent_dma_mask to 0 here to make this more >>> noticeable? It can be done together with the mask calculation from size. >> >> I guess you are the following in the code. >> >> if (!size) { >> dev->coherent_dma_mask = 0; >> dev_err(dev, "Adjusted size 0x%llx invalid\n", size); >> return; >> } >> >> Not sure how this is going to help and how this get handled by the >> caller and subsequent logic. Probably it will cause probe to fail, with >> some helpful error code. > > Not sure how it will fail, maybe the driver figures out that DMA isn't > available and say something or switch to PIO. I guess you can leave it > as 32-bit mask by default for now even in case of size == 0. > > BTW, since pci_device_add() already sets coherent_dma_mask, you could > add another check at the beginning of of_dma_configure(): > > if (!dev->coherent_dma_mask) > dev->coherent_dma_mask = DMA_BIT_MASK(32); > > That's more of a nitpick as the values are both the same. > Catalin,
Just posted a patch for size based dma mask with title "of: calculate masks of the device based on dma-range size". Please review and comment
-- Murali Karicheri Linux Kernel, Texas Instruments
| |