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authorDaniel Vetter <daniel.vetter@ffwll.ch>2014-07-07 10:17:56 +0200
committerDaniel Vetter <daniel.vetter@ffwll.ch>2014-07-07 10:17:56 +0200
commitf1615bbe9be4def59c3b3eaddb60722efeed16c2 (patch)
treeca3020e65447576fc1826e819651e6ba072030b5 /drivers/net/ethernet/sfc/io.h
parentcfb3c0ab0903abb6ea5215b37eebd9c2a1f057eb (diff)
parentcd3de83f147601356395b57a8673e9c5ff1e59d1 (diff)
Merge tag 'v3.16-rc4' into drm-intel-next-queued
Due to Dave's vacation drm-next hasn't opened yet for 3.17 so I couldn't move my drm-intel-next queue forward yet like I usually do. Just pull in the latest upstream -rc to unblock patch merging - I don't want to needlessly rebase my current patch pile really and void all the testing we've done already. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/net/ethernet/sfc/io.h')
-rw-r--r--drivers/net/ethernet/sfc/io.h7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/io.h b/drivers/net/ethernet/sfc/io.h
index 4d3f119b67b..afb94aa2c15 100644
--- a/drivers/net/ethernet/sfc/io.h
+++ b/drivers/net/ethernet/sfc/io.h
@@ -66,10 +66,17 @@
#define EFX_USE_QWORD_IO 1
#endif
+/* Hardware issue requires that only 64-bit naturally aligned writes
+ * are seen by hardware. Its not strictly necessary to restrict to
+ * x86_64 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
#ifdef EFX_USE_QWORD_IO
static inline void _efx_writeq(struct efx_nic *efx, __le64 value,