| Message ID | 20140317144235.546d2e19@marrow.netinsight.se (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Monday 17 March 2014, Simon Kågström wrote: > Non-PCI devices can use the entire 32-bit range, PCI dittos are > limited to the first 64MiB. > > Also actually setup coherent_dma_mask. > > The patch has been verified on a board with 128MiB memory, one > ipx4xx_eth device and a e100 PCI device. > > Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net> > --- I've applied this patch to the next/fixes-non-critical branch of arm-soc. Please let me know if you need to have it backported to older kernels as well. Patch 2 should go through the netdev tree. Arnd
On Tue, 18 Mar 2014 15:58:36 +0100 Arnd Bergmann <arnd@arndb.de> wrote: > On Monday 17 March 2014, Simon Kågström wrote: > > Non-PCI devices can use the entire 32-bit range, PCI dittos are > > limited to the first 64MiB. > > > > Also actually setup coherent_dma_mask. > > > > The patch has been verified on a board with 128MiB memory, one > > ipx4xx_eth device and a e100 PCI device. > > I've applied this patch to the next/fixes-non-critical branch of arm-soc. > Please let me know if you need to have it backported to older kernels > as well. Thanks. However, Krzysztof thinks that this implementation is incorrect. It certainly fixes my ixp4xx issues, but might not be good for everyone. // Simon
Simon Kågström <simon.kagstrom@netinsight.net> writes: > Thanks. However, Krzysztof thinks that this implementation is > incorrect. It certainly fixes my ixp4xx issues, but might not be good > for everyone. It because you don't have PCI devices setting coherent mask to 32-bits (and that's what normal PCI devices do). BTW PCI (and other) devices requesting 32-bit coherent allocs don't care if they're given 26-bit memory. 26 bits fit perfectly in 32 bits. It's the streaming mapping which is (may be) constrained by hardware.
On Thursday 20 March 2014, Krzysztof Ha?asa wrote: > Simon Kågström <simon.kagstrom@netinsight.net> writes: > > > Thanks. However, Krzysztof thinks that this implementation is > > incorrect. It certainly fixes my ixp4xx issues, but might not be good > > for everyone. > > It because you don't have PCI devices setting coherent mask to 32-bits > (and that's what normal PCI devices do). > > BTW PCI (and other) devices requesting 32-bit coherent allocs don't care > if they're given 26-bit memory. 26 bits fit perfectly in 32 bits. It's > the streaming mapping which is (may be) constrained by hardware. Should I revert the patch then until we have a better fix? Arnd
On Thu, 20 Mar 2014 12:02:36 +0100 Arnd Bergmann <arnd@arndb.de> wrote: > On Thursday 20 March 2014, Krzysztof Ha?asa wrote: > > Simon Kågström <simon.kagstrom@netinsight.net> writes: > > > > > Thanks. However, Krzysztof thinks that this implementation is > > > incorrect. It certainly fixes my ixp4xx issues, but might not be good > > > for everyone. > > > > It because you don't have PCI devices setting coherent mask to 32-bits > > (and that's what normal PCI devices do). > > > > BTW PCI (and other) devices requesting 32-bit coherent allocs don't care > > if they're given 26-bit memory. 26 bits fit perfectly in 32 bits. It's > > the streaming mapping which is (may be) constrained by hardware. > > Should I revert the patch then until we have a better fix? Yes, I think that would be good. Thanks to all for looking into it! // Simon
diff --git a/arch/arm/mach-ixp4xx/common-pci.c b/arch/arm/mach-ixp4xx/common-pci.c index 200970d..055d816 100644 --- a/arch/arm/mach-ixp4xx/common-pci.c +++ b/arch/arm/mach-ixp4xx/common-pci.c @@ -481,14 +481,5 @@ int ixp4xx_setup(int nr, struct pci_sys_data *sys) return 1; } -int dma_set_coherent_mask(struct device *dev, u64 mask) -{ - if (mask >= SZ_64M - 1) - return 0; - - return -EIO; -} - EXPORT_SYMBOL(ixp4xx_pci_read); EXPORT_SYMBOL(ixp4xx_pci_write); -EXPORT_SYMBOL(dma_set_coherent_mask); diff --git a/arch/arm/mach-ixp4xx/common.c b/arch/arm/mach-ixp4xx/common.c index 6d68aed..df82a2b 100644 --- a/arch/arm/mach-ixp4xx/common.c +++ b/arch/arm/mach-ixp4xx/common.c @@ -31,6 +31,7 @@ #include <linux/gpio.h> #include <linux/cpu.h> #include <linux/sched_clock.h> +#include <linux/pci.h> #include <mach/udc.h> #include <mach/hardware.h> @@ -578,6 +579,17 @@ void ixp4xx_restart(enum reboot_mode mode, const char *cmd) } } +int dma_set_coherent_mask(struct device *dev, u64 mask) +{ + if (dev_is_pci(dev) && mask >= SZ_64M) + return -EIO; + + dev->coherent_dma_mask = mask; + + return 0; +} +EXPORT_SYMBOL(dma_set_coherent_mask); + #ifdef CONFIG_IXP4XX_INDIRECT_PCI /* * In the case of using indirect PCI, we simply return the actual PCI
Non-PCI devices can use the entire 32-bit range, PCI dittos are limited to the first 64MiB. Also actually setup coherent_dma_mask. The patch has been verified on a board with 128MiB memory, one ipx4xx_eth device and a e100 PCI device. Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net> --- ChangeLog: * v2: Move EXPORT_SYMBOL together with dma_set_coherent_mask (Anrd Bergmann) arch/arm/mach-ixp4xx/common-pci.c | 9 --------- arch/arm/mach-ixp4xx/common.c | 12 ++++++++++++ 2 files changed, 12 insertions(+), 9 deletions(-)