On Tuesday 29 December 2015 21:25:15 Santosh Shukla wrote: > mistakenly added wrong email-id of alex, looping his correct one. > > On 29 December 2015 at 21:23, Santosh Shukla <santosh.shukla@xxxxxxxxxx> wrote: > > On 29 December 2015 at 18:58, Arnd Bergmann <arnd@xxxxxxxx> wrote: > >> On Wednesday 23 December 2015 17:04:40 Santosh Shukla wrote: > >>> On 23 December 2015 at 03:26, Arnd Bergmann <arnd@xxxxxxxx> wrote: > >>> > On Tuesday 22 December 2015, Santosh Shukla wrote: > >>> >> } > >>> >> > >>> >> So I care for /dev/ioport types interface who could do more than byte > >>> >> data copy to/from user-space. I tested this patch with little > >>> >> modification and could able to run pmd driver for arm/arm64 case. > >>> >> > >>> >> Like to know how to address pci_io region mapping problem for > >>> >> arm/arm64, in-case /dev/ioports approach is not acceptable or else I > >>> >> can spent time on restructuring the patch? > >>> >> > >>> > > >>> > For the use case you describe, can't you use the vfio framework to > >>> > access the PCI BARs? > >>> > > >>> > >>> I looked at file: drivers/vfio/pci/vfio_pci.c, func vfio_pci_map() and > >>> it look to me that it only maps ioresource_mem pci region, pasting > >>> code snap: > >>> > >>> if (!(pci_resource_flags(pdev, index) & IORESOURCE_MEM)) > >>> return -EINVAL; > >>> .... > >>> > >>> and I want to map ioresource_io pci region for arm platform in my > >>> use-case. Not sure vfio maps pci_iobar region? > >> > >> Mapping I/O BARs is not portable, notably it doesn't work on x86. > >> > >> You should be able access them using the read/write interface on > >> the vfio device. > >> > > Right, x86 doesn't care as iopl() could give userspace application > > direct access to ioports. > > > > Also, Alex in other dpdk thread [1] suggested someone to propose io > > bar mapping in vfio-pci, I guess in particular to non-x86 arch so I > > started working on it. > > > So what's wrong with just using the existing read/write API on all architectures? Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
