Message ID | 5385AC57.9040000@solarflare.com |
---|---|
State | Changes Requested, archived |
Delegated to: | David Miller |
Headers | show |
Hello. On 05/28/2014 01:28 PM, Shradha Shah wrote: > From: Jon Cooper <jcooper@solarflare.com> > Enable PIO for x86_64 architecture only. > Not tested on platforms other than x86_64. > Fixes:ee45fd92c739db5b7950163d91dfe5f016af6d24 12 digits is enough. And please specify that commit's summary enclosed in parens and quotes. > orig-hg-hash: 53dc43553d9bbe1c5a64c49e580ca571ddc470ae > Signed-off-by: Shradha Shah <sshah@solarflare.com> > --- > drivers/net/ethernet/sfc/io.h | 8 ++++++++ > 1 file changed, 8 insertions(+) WBR, Sergei -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/ethernet/sfc/io.h b/drivers/net/ethernet/sfc/io.h index 4d3f119..adadcf0 100644 --- a/drivers/net/ethernet/sfc/io.h +++ b/drivers/net/ethernet/sfc/io.h @@ -66,10 +66,18 @@ #define EFX_USE_QWORD_IO 1 #endif +/* PIO only works on 64-bit architectures */ +#if BITS_PER_LONG == 64 +/* not strictly necessary to restrict to x86 arch, but done for safety + * since unusual write combining behaviour can break PIO. + */ +#ifdef CONFIG_X86_64 /* PIO is a win only if write-combining is possible */ #ifdef ARCH_HAS_IOREMAP_WC #define EFX_USE_PIO 1 #endif +#endif +#endif #ifdef EFX_USE_QWORD_IO static inline void _efx_writeq(struct efx_nic *efx, __le64 value,