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[1/1] sdhci: sdhc spec 3.0 add some modification

Message ID AANLkTimWaA2x3o60G+cSeAkFhFfLe4YbCVmHZGFy-Zn8@mail.gmail.com (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Zhangfei Gao Aug. 16, 2010, 3:09 a.m. UTC
None
diff mbox

Patch

From c0d23113e5056c9313407ac22d93349501b0b9b2 Mon Sep 17 00:00:00 2001
From: Zhangfei Gao <zgao6@marvell.com>
Date: Fri, 6 Aug 2010 07:10:01 +0800
Subject: [PATCH] sdhc: support 10-bit divided clock Mode

Signed-off-by: Zhangfei Gao <zgao6@marvell.com>
Reviewed-by: Matt Fleming <matt@console-pimps.org>
---
 drivers/mmc/host/sdhci.c |   16 ++++++++++++----
 drivers/mmc/host/sdhci.h |    5 +++++
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 7855121..768fdc9 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -983,7 +983,7 @@  static void sdhci_finish_command(struct sdhci_host *host)
 
 static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
 {
-	int div;
+	int div, max_div;
 	u16 clk;
 	unsigned long timeout;
 
@@ -1001,13 +1001,21 @@  static void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
 	if (clock == 0)
 		goto out;
 
-	for (div = 1;div < 256;div *= 2) {
+	if (host->version >= SDHCI_SPEC_300)
+		max_div = 2046;
+	else
+		max_div = 256;
+
+	if(host->max_clk <= clock)
+		div = 1;
+	for (div = 2; div < max_div; div += 2) {
 		if ((host->max_clk / div) <= clock)
 			break;
 	}
 	div >>= 1;
 
-	clk = div << SDHCI_DIVIDER_SHIFT;
+	clk = (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT;
+	clk |= ((div & SDHCI_DIV_HI_MASK) >> SDHCI_DIV_MASK_LEN) << SDHCI_DIVIDER_HI_SHIFT;
 	clk |= SDHCI_CLOCK_INT_EN;
 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 
@@ -1707,7 +1715,7 @@  int sdhci_add_host(struct sdhci_host *host)
 	host->version = sdhci_readw(host, SDHCI_HOST_VERSION);
 	host->version = (host->version & SDHCI_SPEC_VER_MASK)
 				>> SDHCI_SPEC_VER_SHIFT;
-	if (host->version > SDHCI_SPEC_200) {
+	if (host->version > SDHCI_SPEC_300) {
 		printk(KERN_ERR "%s: Unknown controller version (%d). "
 			"You may experience problems.\n", mmc_hostname(mmc),
 			host->version);
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 036cfae..50860dc 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -86,6 +86,10 @@ 
 
 #define SDHCI_CLOCK_CONTROL	0x2C
 #define  SDHCI_DIVIDER_SHIFT	8
+#define  SDHCI_DIVIDER_HI_SHIFT	6
+#define  SDHCI_DIV_MASK	0xFF
+#define  SDHCI_DIV_MASK_LEN	8
+#define  SDHCI_DIV_HI_MASK	0x300
 #define  SDHCI_CLOCK_CARD_EN	0x0004
 #define  SDHCI_CLOCK_INT_STABLE	0x0002
 #define  SDHCI_CLOCK_INT_EN	0x0001
@@ -178,6 +182,7 @@ 
 #define  SDHCI_SPEC_VER_SHIFT	0
 #define   SDHCI_SPEC_100	0
 #define   SDHCI_SPEC_200	1
+#define   SDHCI_SPEC_300	2
 
 struct sdhci_ops;
 
-- 
1.7.0.4