[PATCH 02/16] dmaengine: ste_dma40: use writel_relaxed for lcxa

From: Fabio Baltieri
Date: Mon Jan 07 2013 - 06:23:14 EST


From: Per Forlin <per.forlin@xxxxxxxxxxxxxx>

lcpa and lcla are written often and the cache_sync() overhead in writel
is costly, especially for wlan where every single network packet (in RX
mode) corresponds to a separate DMA transfer.

Signed-off-by: Per Forlin <per.forlin@xxxxxxxxxxxxxx>
Reviewed-by: Narayanan Gopalakrishnan <narayanan.gopalakrishnan@xxxxxxxxxxxxxx>
Reviewed-by: Rabin Vincent <rabin.vincent@xxxxxxxxxxxxxx>
Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Signed-off-by: Fabio Baltieri <fabio.baltieri@xxxxxxxxxx>
---
drivers/dma/ste_dma40_ll.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/ste_dma40_ll.c b/drivers/dma/ste_dma40_ll.c
index d64b72a..1cfe7ab 100644
--- a/drivers/dma/ste_dma40_ll.c
+++ b/drivers/dma/ste_dma40_ll.c
@@ -332,10 +332,10 @@ void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
{
d40_log_lli_link(lli_dst, lli_src, next, flags);

- writel(lli_src->lcsp02, &lcpa[0].lcsp0);
- writel(lli_src->lcsp13, &lcpa[0].lcsp1);
- writel(lli_dst->lcsp02, &lcpa[0].lcsp2);
- writel(lli_dst->lcsp13, &lcpa[0].lcsp3);
+ writel_relaxed(lli_src->lcsp02, &lcpa[0].lcsp0);
+ writel_relaxed(lli_src->lcsp13, &lcpa[0].lcsp1);
+ writel_relaxed(lli_dst->lcsp02, &lcpa[0].lcsp2);
+ writel_relaxed(lli_dst->lcsp13, &lcpa[0].lcsp3);
}

void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
@@ -345,10 +345,10 @@ void d40_log_lli_lcla_write(struct d40_log_lli *lcla,
{
d40_log_lli_link(lli_dst, lli_src, next, flags);

- writel(lli_src->lcsp02, &lcla[0].lcsp02);
- writel(lli_src->lcsp13, &lcla[0].lcsp13);
- writel(lli_dst->lcsp02, &lcla[1].lcsp02);
- writel(lli_dst->lcsp13, &lcla[1].lcsp13);
+ writel_relaxed(lli_src->lcsp02, &lcla[0].lcsp02);
+ writel_relaxed(lli_src->lcsp13, &lcla[0].lcsp13);
+ writel_relaxed(lli_dst->lcsp02, &lcla[1].lcsp02);
+ writel_relaxed(lli_dst->lcsp13, &lcla[1].lcsp13);
}

static void d40_log_fill_lli(struct d40_log_lli *lli,
--
1.7.12.1

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