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mmc: dw-mmc: ensure that the card is not busy when changing clock

PATCH In review Jaehoon Chung 2 participants 5 messages Aug 28, 2012 – Aug 30, 2012

Subsystems (2)
MMC, SD and SDIO Synopsys DesignWare MMC/SD/SDIO driver
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Jaehoon Chung

author maintainer
#0 lore raw

PATCH v2 1/5 mmc: dw-mmc: ensure that the card is not busy when changing clock

synopsys spec is mentioned. (7.1 Software/Hardware Restrictions)
"Before disabling clock, ensure that card is not busy due to any previous data command."

At specific board, i found the problem that didn't inform ciu.
(It didn't produce always.)
At that time, i checked the status register whether card is busy or not. (Start bit of CMD register is cleared, but card is busy.)
Current code didn't check the card status. Just check whether the start-bit cleared. host regard that command is completed, will send the next command.
But next command didn't issue because Card is busy.
This patch can prevent this situation.

Signed-off-by Jaehoon Chung <[email protected]>
---
 drivers/mmc/host/dw_mmc.c |   27 +++++++++++++++++++++------
 drivers/mmc/host/dw_mmc.h |    1 +
 2 files changed, 22 insertions(+), 6 deletions(-)
drivers/mmc/host/dw_mmc.c +21 -6
index 36f98c0..e30d3ed 100644
@@ -623,6 +623,24 @@ static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
 		cmd, arg, cmd_status);
 }
 
+static void dw_mci_inform_ciu(struct dw_mci_slot *slot)
+{
+	struct dw_mci *host = slot->host;
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);
+	u32 ctrl, status;
+
+	do {
+		status = mci_readl(host, STATUS);
+		if (!(status & SDMMC_DATA_BUSY))
+			break;
+		ctrl = mci_readl(host, CTRL);
+		ctrl |= SDMMC_CTRL_RESET;
+		mci_writel(host, CTRL, ctrl);
+	} while (time_before(jiffies, timeout));
+
+	mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+}
+
 static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 {
 	struct dw_mci *host = slot->host;

@@ -650,15 +668,13 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 		mci_writel(host, CLKSRC, 0);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		/* set clock to desired speed */
 		mci_writel(host, CLKDIV, div);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		/* enable clock; only low power if no SDIO */
 		clk_en_a = SDMMC_CLKEN_ENABLE << slot->id;

@@ -667,8 +683,7 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 		mci_writel(host, CLKENA, clk_en_a);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		host->current_speed = slot->clock;
 	}
drivers/mmc/host/dw_mmc.h +1 -0
index 15c27e1..b6a1a78 100644
@@ -127,6 +127,7 @@
 #define SDMMC_CMD_INDX(n)		((n) & 0x1F)
 /* Status register defines */
 #define SDMMC_GET_FCNT(x)		(((x)>>17) & 0x1FFF)
+#define SDMMC_DATA_BUSY			BIT(9)
 /* Internal DMAC interrupt defines */
 #define SDMMC_IDMAC_INT_AI		BIT(9)
 #define SDMMC_IDMAC_INT_NI		BIT(8)
Signature · 1 line
1.7.4.1
#1 lore raw
Quoted 23 lines · Jaehoon Chung

synopsys spec is mentioned. (7.1 Software/Hardware Restrictions)
"Before disabling clock, ensure that card is not busy due to any previous data command."

At specific board, i found the problem that didn't inform ciu.
(It didn't produce always.)
At that time, i checked the status register whether card is busy or not. (Start bit of CMD register is cleared, but card is busy.)
Current code didn't check the card status. Just check whether the start-bit cleared. host regard that command is completed, will send the next command.
But next command didn't issue because Card is busy.
This patch can prevent this situation.

Signed-off-by Jaehoon Chung <[email protected]>
---
 drivers/mmc/host/dw_mmc.c |   27 +++++++++++++++++++++------
 drivers/mmc/host/dw_mmc.h |    1 +
 2 files changed, 22 insertions(+), 6 deletions(-)
drivers/mmc/host/dw_mmc.c +0 -0
index 36f98c0..e30d3ed 100644

drivers/mmc/host/dw_mmc.c static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg) · line 629

Quoted 7 lines
drivers/mmc/host/dw_mmc.c +4 -0
@@ -623,6 +623,24 @@ static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
 		cmd, arg, cmd_status);
 }
 
+static void dw_mci_inform_ciu(struct dw_mci_slot *slot)
+{
+	struct dw_mci *host = slot->host;
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);

10ms is from test?

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot)

Quoted 18 lines
drivers/mmc/host/dw_mmc.c +14 -0
+	u32 ctrl, status;
+
+	do {
+		status = mci_readl(host, STATUS);
+		if (!(status & SDMMC_DATA_BUSY))
+			break;
+		ctrl = mci_readl(host, CTRL);
+		ctrl |= SDMMC_CTRL_RESET;
+		mci_writel(host, CTRL, ctrl);
+	} while (time_before(jiffies, timeout));
+
+	mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+}
+
 static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 {
 	struct dw_mci *host = slot->host;

@@ -650,15 +668,13 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)

According to your quotation of manual("Before disabling clock, ...), Place of dw_mci_inform_ciu is proper here?

	dw_mci_inform_ciu(slot);
	
          /* disable clock */
         mci_writel(host, CLKENA, 0);
         mci_writel(host, CLKSRC, 0);
Quoted 4 lines
drivers/mmc/host/dw_mmc.c +0 -1
 		mci_writel(host, CLKSRC, 0);
 
 		/* inform CIU */
-		mci_send_cmd(slot,

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 677

Quoted 10 lines
drivers/mmc/host/dw_mmc.c +2 -3
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		/* set clock to desired speed */
 		mci_writel(host, CLKDIV, div);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

And then, since start to change clock sequence, there is no need to check busy-status. Just need to update clock with origin code.

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 686

Quoted 10 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		/* enable clock; only low power if no SDIO */
 		clk_en_a = SDMMC_CLKEN_ENABLE << slot->id;

@@ -667,8 +683,7 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 		mci_writel(host, CLKENA, clk_en_a);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

Same here.

Thanks,
Seungwon Jeon

Quoted 17 lines
drivers/mmc/host/dw_mmc.c +0 -0
 		host->current_speed = slot->clock;
 	}
drivers/mmc/host/dw_mmc.h +1 -1
index 15c27e1..b6a1a78 100644
@@ -127,6 +127,7 @@
 #define SDMMC_CMD_INDX(n)		((n) & 0x1F)
 /* Status register defines */
 #define SDMMC_GET_FCNT(x)		(((x)>>17) & 0x1FFF)
+#define SDMMC_DATA_BUSY			BIT(9)
 /* Internal DMAC interrupt defines */
 #define SDMMC_IDMAC_INT_AI		BIT(9)
 #define SDMMC_IDMAC_INT_NI		BIT(8)
--

1.7.4.1

author maintainer
#2 lore raw
Quoted 27 lines · Seungwon Jeon
Quoted 26 lines · Jaehoon Chung

synopsys spec is mentioned. (7.1 Software/Hardware Restrictions)
"Before disabling clock, ensure that card is not busy due to any previous data command."

At specific board, i found the problem that didn't inform ciu.
(It didn't produce always.)
At that time, i checked the status register whether card is busy or not. (Start bit of CMD register is cleared, but card is busy.)
Current code didn't check the card status. Just check whether the start-bit cleared. host regard that command is completed, will send the next command.
But next command didn't issue because Card is busy.
This patch can prevent this situation.

Signed-off-by Jaehoon Chung <[email protected]>
---
 drivers/mmc/host/dw_mmc.c |   27 +++++++++++++++++++++------
 drivers/mmc/host/dw_mmc.h |    1 +
 2 files changed, 22 insertions(+), 6 deletions(-)
drivers/mmc/host/dw_mmc.c +0 -0
index 36f98c0..e30d3ed 100644
@@ -623,6 +623,24 @@ static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
 		cmd, arg, cmd_status);
 }
Quoted 5 lines

drivers/mmc/host/dw_mmc.c static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg) · line 629

Quoted 4 lines
drivers/mmc/host/dw_mmc.c +4 -0
+static void dw_mci_inform_ciu(struct dw_mci_slot *slot)
+{
+	struct dw_mci *host = slot->host;
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);

10ms is from test?

It's tested...it's not exactly value..but never spent the time.

Quoted 13 lines
Quoted 13 lines
drivers/mmc/host/dw_mmc.c +12 -0
+	u32 ctrl, status;
+
+	do {
+		status = mci_readl(host, STATUS);
+		if (!(status & SDMMC_DATA_BUSY))
+			break;
+		ctrl = mci_readl(host, CTRL);
+		ctrl |= SDMMC_CTRL_RESET;
+		mci_writel(host, CTRL, ctrl);
+	} while (time_before(jiffies, timeout));
+
+	mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
Quoted 8 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot)

Quoted 6 lines
drivers/mmc/host/dw_mmc.c +2 -0
+}
+
 static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 {
 	struct dw_mci *host = slot->host;

@@ -650,15 +668,13 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)

According to your quotation of manual("Before disabling clock, ...), Place of dw_mci_inform_ciu is proper here?

manual is mentioned "before the disabling clock". but i think no problem before send the command.

Quoted 17 lines
	dw_mci_inform_ciu(slot);
	
          /* disable clock */
         mci_writel(host, CLKENA, 0);
         mci_writel(host, CLKSRC, 0);
Quoted 10 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		mci_writel(host, CLKSRC, 0);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		/* set clock to desired speed */
 		mci_writel(host, CLKDIV, div);
Quoted 6 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 671

Quoted 4 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

And then, since start to change clock sequence, there is no need to check busy-status. Just need to update clock with origin code.

Right, didn't check the busy-status. but there is also no reason that didn't need to check busy-status.

Quoted 37 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 686

Quoted 10 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		/* enable clock; only low power if no SDIO */
 		clk_en_a = SDMMC_CLKEN_ENABLE << slot->id;

@@ -667,8 +683,7 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 		mci_writel(host, CLKENA, clk_en_a);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

Same here.

Thanks,
Seungwon Jeon

Quoted 16 lines
drivers/mmc/host/dw_mmc.c +0 -0
 		host->current_speed = slot->clock;
 	}
drivers/mmc/host/dw_mmc.h +1 -1
index 15c27e1..b6a1a78 100644
@@ -127,6 +127,7 @@
 #define SDMMC_CMD_INDX(n)		((n) & 0x1F)
 /* Status register defines */
 #define SDMMC_GET_FCNT(x)		(((x)>>17) & 0x1FFF)
+#define SDMMC_DATA_BUSY			BIT(9)
 /* Internal DMAC interrupt defines */
 #define SDMMC_IDMAC_INT_AI		BIT(9)
 #define SDMMC_IDMAC_INT_NI		BIT(8)
--
Quoted 1 line

1.7.4.1

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#3 lore raw
Quoted 73 lines · Jaehoon Chung
Quoted 27 lines · Seungwon Jeon
Quoted 26 lines · Jaehoon Chung

synopsys spec is mentioned. (7.1 Software/Hardware Restrictions)
"Before disabling clock, ensure that card is not busy due to any previous data command."

At specific board, i found the problem that didn't inform ciu.
(It didn't produce always.)
At that time, i checked the status register whether card is busy or not. (Start bit of CMD register is cleared, but card is busy.)
Current code didn't check the card status. Just check whether the start-bit cleared. host regard that command is completed, will send the next command.
But next command didn't issue because Card is busy.
This patch can prevent this situation.

Signed-off-by Jaehoon Chung <[email protected]>
---
 drivers/mmc/host/dw_mmc.c |   27 +++++++++++++++++++++------
 drivers/mmc/host/dw_mmc.h |    1 +
 2 files changed, 22 insertions(+), 6 deletions(-)
drivers/mmc/host/dw_mmc.c +0 -0
index 36f98c0..e30d3ed 100644
@@ -623,6 +623,24 @@ static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
 		cmd, arg, cmd_status);
 }
Quoted 5 lines

drivers/mmc/host/dw_mmc.c static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg) · line 629

Quoted 4 lines
drivers/mmc/host/dw_mmc.c +4 -0
+static void dw_mci_inform_ciu(struct dw_mci_slot *slot)
+{
+	struct dw_mci *host = slot->host;
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);

10ms is from test?

It's tested...it's not exactly value..but never spent the time.

Quoted 13 lines
Quoted 13 lines
drivers/mmc/host/dw_mmc.c +12 -0
+	u32 ctrl, status;
+
+	do {
+		status = mci_readl(host, STATUS);
+		if (!(status & SDMMC_DATA_BUSY))
+			break;
+		ctrl = mci_readl(host, CTRL);
+		ctrl |= SDMMC_CTRL_RESET;
+		mci_writel(host, CTRL, ctrl);
+	} while (time_before(jiffies, timeout));
+
+	mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
Quoted 8 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot)

Quoted 6 lines
drivers/mmc/host/dw_mmc.c +2 -0
+}
+
 static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 {
 	struct dw_mci *host = slot->host;

@@ -650,15 +668,13 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)

According to your quotation of manual("Before disabling clock, ...), Place of dw_mci_inform_ciu is proper here?

manual is mentioned "before the disabling clock". but i think no problem before send the command.

Quoted 17 lines
	dw_mci_inform_ciu(slot);

          /* disable clock */
         mci_writel(host, CLKENA, 0);
         mci_writel(host, CLKSRC, 0);
Quoted 10 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		mci_writel(host, CLKSRC, 0);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		/* set clock to desired speed */
 		mci_writel(host, CLKDIV, div);
Quoted 7 lines
Quoted 6 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 671

Quoted 4 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

And then, since start to change clock sequence, there is no need to check busy-status. Just need to update clock with origin code.

Right, didn't check the busy-status. but there is also no reason that didn't need to check busy-status.

Ok, I mentioned no check busy-status because host doesn't send command to card in the middle of host's clock update. If you have a opinion, please let me know.

Thanks,
Seungwon Jeon

Quoted 42 lines
Quoted 28 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 686

Quoted 10 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		/* enable clock; only low power if no SDIO */
 		clk_en_a = SDMMC_CLKEN_ENABLE << slot->id;

@@ -667,8 +683,7 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 		mci_writel(host, CLKENA, clk_en_a);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

Same here.

Thanks,
Seungwon Jeon

Quoted 14 lines
drivers/mmc/host/dw_mmc.c +0 -0
 		host->current_speed = slot->clock;
 	}
drivers/mmc/host/dw_mmc.h +1 -0
index 15c27e1..b6a1a78 100644
@@ -127,6 +127,7 @@
 #define SDMMC_CMD_INDX(n)		((n) & 0x1F)
 /* Status register defines */
 #define SDMMC_GET_FCNT(x)		(((x)>>17) & 0x1FFF)
+#define SDMMC_DATA_BUSY			BIT(9)
 /* Internal DMAC interrupt defines */
 #define SDMMC_IDMAC_INT_AI		BIT(9)
Quoted 9 lines
Quoted 3 lines
drivers/mmc/host/dw_mmc.h +0 -1
 #define SDMMC_IDMAC_INT_NI		BIT(8)
--

1.7.4.1

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author maintainer
#4 lore raw
Quoted 80 lines · Seungwon Jeon
Quoted 79 lines · Jaehoon Chung
Quoted 27 lines · Seungwon Jeon
Quoted 26 lines · Jaehoon Chung

synopsys spec is mentioned. (7.1 Software/Hardware Restrictions)
"Before disabling clock, ensure that card is not busy due to any previous data command."

At specific board, i found the problem that didn't inform ciu.
(It didn't produce always.)
At that time, i checked the status register whether card is busy or not. (Start bit of CMD register is cleared, but card is busy.)
Current code didn't check the card status. Just check whether the start-bit cleared. host regard that command is completed, will send the next command.
But next command didn't issue because Card is busy.
This patch can prevent this situation.

Signed-off-by Jaehoon Chung <[email protected]>
---
 drivers/mmc/host/dw_mmc.c |   27 +++++++++++++++++++++------
 drivers/mmc/host/dw_mmc.h |    1 +
 2 files changed, 22 insertions(+), 6 deletions(-)
drivers/mmc/host/dw_mmc.c +0 -0
index 36f98c0..e30d3ed 100644
@@ -623,6 +623,24 @@ static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg)
 		cmd, arg, cmd_status);
 }
Quoted 5 lines

drivers/mmc/host/dw_mmc.c static void mci_send_cmd(struct dw_mci_slot *slot, u32 cmd, u32 arg) · line 629

Quoted 4 lines
drivers/mmc/host/dw_mmc.c +4 -0
+static void dw_mci_inform_ciu(struct dw_mci_slot *slot)
+{
+	struct dw_mci *host = slot->host;
+	unsigned long timeout = jiffies + msecs_to_jiffies(10);

10ms is from test?

It's tested...it's not exactly value..but never spent the time.

Quoted 13 lines
Quoted 13 lines
drivers/mmc/host/dw_mmc.c +12 -0
+	u32 ctrl, status;
+
+	do {
+		status = mci_readl(host, STATUS);
+		if (!(status & SDMMC_DATA_BUSY))
+			break;
+		ctrl = mci_readl(host, CTRL);
+		ctrl |= SDMMC_CTRL_RESET;
+		mci_writel(host, CTRL, ctrl);
+	} while (time_before(jiffies, timeout));
+
+	mci_send_cmd(slot, SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
Quoted 8 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot)

Quoted 6 lines
drivers/mmc/host/dw_mmc.c +2 -0
+}
+
 static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 {
 	struct dw_mci *host = slot->host;

@@ -650,15 +668,13 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)

According to your quotation of manual("Before disabling clock, ...), Place of dw_mci_inform_ciu is proper here?

manual is mentioned "before the disabling clock". but i think no problem before send the command.

Quoted 23 lines
	dw_mci_inform_ciu(slot);

          /* disable clock */
         mci_writel(host, CLKENA, 0);
         mci_writel(host, CLKSRC, 0);
Quoted 4 lines
drivers/mmc/host/dw_mmc.c +0 -1
 		mci_writel(host, CLKSRC, 0);
 
 		/* inform CIU */
-		mci_send_cmd(slot,

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 677

Quoted 10 lines
drivers/mmc/host/dw_mmc.c +2 -3
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);
 
 		/* set clock to desired speed */
 		mci_writel(host, CLKDIV, div);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

And then, since start to change clock sequence, there is no need to check busy-status. Just need to update clock with origin code.

Quoted 3 lines
Quoted 1 line

Right, didn't check the busy-status. but there is also no reason that didn't need to check busy-status.

Ok, I mentioned no check busy-status because host doesn't send command to card in the middle of host's clock update. If you have a opinion, please let me know.

OK, i will apply with your opinion.
Then resend the patch.

Best Regards,
Jaehoon Chung

Quoted 48 lines

Thanks,
Seungwon Jeon

Quoted 42 lines
Quoted 28 lines

drivers/mmc/host/dw_mmc.c static void dw_mci_setup_bus(struct dw_mci_slot *slot) · line 686

Quoted 10 lines
drivers/mmc/host/dw_mmc.c +1 -2
 		/* enable clock; only low power if no SDIO */
 		clk_en_a = SDMMC_CLKEN_ENABLE << slot->id;

@@ -667,8 +683,7 @@ static void dw_mci_setup_bus(struct dw_mci_slot *slot)
 		mci_writel(host, CLKENA, clk_en_a);
 
 		/* inform CIU */
-		mci_send_cmd(slot,
-			     SDMMC_CMD_UPD_CLK | SDMMC_CMD_PRV_DAT_WAIT, 0);
+		dw_mci_inform_ciu(slot);

Same here.

Thanks,
Seungwon Jeon

Quoted 14 lines
drivers/mmc/host/dw_mmc.c +0 -0
 		host->current_speed = slot->clock;
 	}
drivers/mmc/host/dw_mmc.h +1 -0
index 15c27e1..b6a1a78 100644
@@ -127,6 +127,7 @@
 #define SDMMC_CMD_INDX(n)		((n) & 0x1F)
 /* Status register defines */
 #define SDMMC_GET_FCNT(x)		(((x)>>17) & 0x1FFF)
+#define SDMMC_DATA_BUSY			BIT(9)
 /* Internal DMAC interrupt defines */
 #define SDMMC_IDMAC_INT_AI		BIT(9)
Quoted 9 lines
Quoted 3 lines
drivers/mmc/host/dw_mmc.h +0 -1
 #define SDMMC_IDMAC_INT_NI		BIT(8)
--

1.7.4.1

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