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authorSimon Glass <sjg@chromium.org>2016-01-21 19:44:03 -0700
committerSimon Glass <sjg@chromium.org>2016-01-21 20:42:35 -0700
commit28a943c11018f7e2946f3a529de87102f268cedb (patch)
treedb57df246af2bfaec66e3d92ca62c593fade6a35 /drivers/spi
parenta49dc0a91456dda9baec7e4778de4d96fa9174ec (diff)
downloadblackbird-obmc-uboot-28a943c11018f7e2946f3a529de87102f268cedb.tar.gz
blackbird-obmc-uboot-28a943c11018f7e2946f3a529de87102f268cedb.zip
rockchip: spi: Remember the last speed to avoid re-setting it
Rather than changing the clock to the same value on every transaction, remember the last value and don't adjust the clock unless it is necessary. Signed-off-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r--drivers/spi/rk_spi.c5
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/spi/rk_spi.c b/drivers/spi/rk_spi.c
index 2b58393e35..aaf139d823 100644
--- a/drivers/spi/rk_spi.c
+++ b/drivers/spi/rk_spi.c
@@ -44,6 +44,7 @@ struct rockchip_spi_priv {
u8 bits_per_word; /* max 16 bits per word */
u8 n_bytes;
unsigned int speed_hz;
+ unsigned int last_speed_hz;
unsigned int tmode;
uint input_rate;
};
@@ -82,6 +83,7 @@ static void rkspi_set_clk(struct rockchip_spi_priv *priv, uint speed)
debug("spi speed %u, div %u\n", speed, clk_div);
writel(clk_div, &priv->regs->baudr);
+ priv->last_speed_hz = speed;
}
static int rkspi_wait_till_not_busy(struct rockchip_spi *regs)
@@ -212,7 +214,8 @@ static int rockchip_spi_claim_bus(struct udevice *dev)
return -EPROTONOSUPPORT;
}
- rkspi_set_clk(priv, priv->speed_hz);
+ if (priv->speed_hz != priv->last_speed_hz)
+ rkspi_set_clk(priv, priv->speed_hz);
/* Operation Mode */
ctrlr0 = OMOD_MASTER << OMOD_SHIFT;
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