[U-Boot] [PATCH] mmc: atmel_sdhci: not on capabilities to set gck rate
Wenyou Yang
wenyou.yang at microchip.com
Fri Nov 17 06:51:27 UTC 2017
From: Ludovic Desroches <ludovic.desroches at microchip.com>
The capabilities have default values which doesn't reflect the reality
when it concerns the base clock and the mul value. Use a fixe rate
for the gck. 240 MHz is an arbitrary choice, it is a multiple of the
maximum SD clock frequency handle by the controller and it allows to
get a 400 kHz clock for the card initialisation.
Signed-off-by: Ludovic Desroches <ludovic.desroches at microchip.com>
Signed-off-by: Wenyou Yang <wenyou.yang at microchip.com>
---
drivers/mmc/atmel_sdhci.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/drivers/mmc/atmel_sdhci.c b/drivers/mmc/atmel_sdhci.c
index c19a1f36b6..9b37e32c8d 100644
--- a/drivers/mmc/atmel_sdhci.c
+++ b/drivers/mmc/atmel_sdhci.c
@@ -13,6 +13,7 @@
#include <asm/arch/clk.h>
#define ATMEL_SDHC_MIN_FREQ 400000
+#define ATMEL_SDHC_GCK_RATE 240000000
#ifndef CONFIG_DM_MMC
int atmel_sdhci_init(void *regbase, u32 id)
@@ -57,9 +58,6 @@ static int atmel_sdhci_probe(struct udevice *dev)
struct atmel_sdhci_plat *plat = dev_get_platdata(dev);
struct sdhci_host *host = dev_get_priv(dev);
u32 max_clk;
- u32 caps, caps_1;
- u32 clk_base, clk_mul;
- ulong gck_rate;
struct clk clk;
int ret;
@@ -78,17 +76,11 @@ static int atmel_sdhci_probe(struct udevice *dev)
host->bus_width = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
"bus-width", 4);
- caps = sdhci_readl(host, SDHCI_CAPABILITIES);
- clk_base = (caps & SDHCI_CLOCK_V3_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
- caps_1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
- clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >> SDHCI_CLOCK_MUL_SHIFT;
- gck_rate = clk_base * 1000000 * (clk_mul + 1);
-
ret = clk_get_by_index(dev, 1, &clk);
if (ret)
return ret;
- ret = clk_set_rate(&clk, gck_rate);
+ ret = clk_set_rate(&clk, ATMEL_SDHC_GCK_RATE);
if (ret)
return ret;
--
2.13.0
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