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authorDavid S. Miller <davem@davemloft.net>2012-05-07 23:35:40 -0400
committerDavid S. Miller <davem@davemloft.net>2012-05-07 23:35:40 -0400
commit0d6c4a2e4641bbc556dd74d3aa158c413a972492 (patch)
treeda944af17682659bb433dc2282dcb48380c14cd1 /arch/arm/plat-omap/dma.c
parent6e06c0e2347ec79d0bd5702b2438fe883f784545 (diff)
parent1c430a727fa512500a422ffe4712166c550ea06a (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts: drivers/net/ethernet/intel/e1000e/param.c drivers/net/wireless/iwlwifi/iwl-agn-rx.c drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c drivers/net/wireless/iwlwifi/iwl-trans.h Resolved the iwlwifi conflict with mainline using 3-way diff posted by John Linville and Stephen Rothwell. In 'net' we added a bug fix to make iwlwifi report a more accurate skb->truesize but this conflicted with RX path changes that happened meanwhile in net-next. In e1000e a conflict arose in the validation code for settings of adapter->itr. 'net-next' had more sophisticated logic so that logic was used. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/arm/plat-omap/dma.c')
-rw-r--r--arch/arm/plat-omap/dma.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
index ecdb3da0dea..c58d896cd5c 100644
--- a/arch/arm/plat-omap/dma.c
+++ b/arch/arm/plat-omap/dma.c
@@ -916,6 +916,13 @@ void omap_start_dma(int lch)
l |= OMAP_DMA_CCR_BUFFERING_DISABLE;
l |= OMAP_DMA_CCR_EN;
+ /*
+ * As dma_write() uses IO accessors which are weakly ordered, there
+ * is no guarantee that data in coherent DMA memory will be visible
+ * to the DMA device. Add a memory barrier here to ensure that any
+ * such data is visible prior to enabling DMA.
+ */
+ mb();
p->dma_write(l, CCR, lch);
dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
@@ -965,6 +972,13 @@ void omap_stop_dma(int lch)
p->dma_write(l, CCR, lch);
}
+ /*
+ * Ensure that data transferred by DMA is visible to any access
+ * after DMA has been disabled. This is important for coherent
+ * DMA regions.
+ */
+ mb();
+
if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
int next_lch, cur_lch = lch;
char dma_chan_link_map[dma_lch_count];