[U-Boot] [PATCH 1/2] SPI: mxc_spi: fix swapping bug and add missing swapping in unaligned rx case

[U-Boot] [PATCH 1/2] SPI: mxc_spi: fix swapping bug and add missing swapping in unaligned rx case

[Anatolij Gustschin]

We need to shift only one time in each cycle in the swapping loop
for unaligned tx case. Currently two byte shift operations are
performed in each loop cycle causing zero gaps in the transmited
data, so not all data scheduled for transmition is actually
transmited.

The proper swapping in unaligned rx case is missing, so add it
as we need to put the received data into the rx buffer in the
correct byte order.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
---
 drivers/spi/mxc_spi.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
index d558137..9ed2891 100644
--- a/drivers/spi/mxc_spi.c
+++ b/drivers/spi/mxc_spi.c
@@ -304,7 +304,7 @@ int spi_xchg_single(struct spi_slave *slave, unsigned int bitlen,
 			/* Buffer is not 32-bit aligned */
 			if ((unsigned long)dout & 0x03) {
 				data = 0;
-				for (i = 0; i < 4; i++, data <<= 8) {
+				for (i = 0; i < 4; i++) {
 					data = (data << 8) | (*dout++ & 0xFF);
 				}
 			} else {
@@ -337,11 +337,11 @@ int spi_xchg_single(struct spi_slave *slave, unsigned int bitlen,
 	if (bitlen % 32) {
 		data = reg_read(mxcs->base + MXC_CSPIRXDATA);
 		cnt = (bitlen % 32) / 8;
+		data = cpu_to_be32(data) >> ((sizeof(data) - cnt) * 8);
 		debug("SPI Rx unaligned: 0x%x\n", data);
 		if (din) {
-			for (i = 0; i < cnt; i++, data >>= 8) {
-				*din++ = data & 0xFF;
-			}
+			memcpy(din, &data, cnt);
+			din += cnt;
 		}
 		nbytes -= cnt;
 	}
-- 
1.7.1

[U-Boot] [PATCH 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Anatolij Gustschin]

The MXC SPI driver didn't calculate the SPI clock up to
now and just used lowest possible divider 512 for DATA
RATE in the control register. This results in very low
transfer rates.

The patch adds code to calculate and setup the SPI clock
frequency for transfers.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
---
 drivers/spi/mxc_spi.c |   22 +++++++++++++++++++++-
 1 files changed, 21 insertions(+), 1 deletions(-)

diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
index 9ed2891..07c62c2 100644
--- a/drivers/spi/mxc_spi.c
+++ b/drivers/spi/mxc_spi.c
@@ -438,12 +438,25 @@ static int decode_cs(struct mxc_spi_slave *mxcs, unsigned int cs)
 	return cs;
 }
 
+u32 get_cspi_div(u32 div)
+{
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		if (div <= (4 << i))
+			return i;
+	}
+	return i;
+}
+
 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
 			unsigned int max_hz, unsigned int mode)
 {
 	unsigned int ctrl_reg;
 	struct mxc_spi_slave *mxcs;
 	int ret;
+	u32 clk_src;
+	u32 div;
 
 	if (bus >= ARRAY_SIZE(spi_bases))
 		return NULL;
@@ -477,9 +490,16 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
 		return NULL;
 	}
 #else
+	clk_src = mx31_get_ipg_clk();
+	div = clk_src / max_hz;
+	div = get_cspi_div(div);
+
+	debug("clk %d Hz, div %d, real clk %d Hz\n",
+		max_hz, div, clk_src / (4 << div));
+
 	ctrl_reg = MXC_CSPICTRL_CHIPSELECT(cs) |
 		MXC_CSPICTRL_BITCOUNT(31) |
-		MXC_CSPICTRL_DATARATE(7) | /* FIXME: calculate data rate */
+		MXC_CSPICTRL_DATARATE(div) |
 		MXC_CSPICTRL_EN |
 		MXC_CSPICTRL_MODE;
 
-- 
1.7.1

[U-Boot] [PATCH 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Stefano Babic]

On 01/16/2011 07:17 PM, Anatolij Gustschin wrote:
> The MXC SPI driver didn't calculate the SPI clock up to
> now and just used lowest possible divider 512 for DATA
> RATE in the control register. This results in very low
> transfer rates.
> 

Hi August,

I sent last friday a patch for mxc_spi.c, too, adding support for mx35,
and the two patches now conflict. Is it ok for you if I rebase your
patch on top of mine and I post it again ?

Best Regards,
Stefano

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de
=====================================================================

[U-Boot] [PATCH 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Anatolij Gustschin]

Hello Stefano,

On Mon, 17 Jan 2011 10:00:51 +0100
Stefano Babic <sbabic@denx.de> wrote:

> On 01/16/2011 07:17 PM, Anatolij Gustschin wrote:
> > The MXC SPI driver didn't calculate the SPI clock up to
> > now and just used lowest possible divider 512 for DATA
> > RATE in the control register. This results in very low
> > transfer rates.
> > 
> 
> Hi August,
> 
> I sent last friday a patch for mxc_spi.c, too, adding support for mx35,
> and the two patches now conflict. Is it ok for you if I rebase your
> patch on top of mine and I post it again ?

Yes, it is ok.

Thanks,
Anatolij

--
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de

[U-Boot] [PATCH 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Anatolij Gustschin]

On Mon, 17 Jan 2011 10:30:09 +0100
Anatolij Gustschin <agust@denx.de> wrote:

> Hello Stefano,
> 
> On Mon, 17 Jan 2011 10:00:51 +0100
> Stefano Babic <sbabic@denx.de> wrote:
> 
> > On 01/16/2011 07:17 PM, Anatolij Gustschin wrote:
> > > The MXC SPI driver didn't calculate the SPI clock up to
> > > now and just used lowest possible divider 512 for DATA
> > > RATE in the control register. This results in very low
> > > transfer rates.
> > > 
> > 
> > Hi August,
> > 
> > I sent last friday a patch for mxc_spi.c, too, adding support for mx35,
> > and the two patches now conflict. Is it ok for you if I rebase your
> > patch on top of mine and I post it again ?
> 
> Yes, it is ok.

BTW: While at it, could you then also please fix a mistake in the
commit description: it should be "... just highest possible divider
512".

Thanks,
Anatolij

--
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de

[U-Boot] [PATCH 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Stefano Babic]

On 01/17/2011 10:36 AM, Anatolij Gustschin wrote:

> BTW: While at it, could you then also please fix a mistake in the
> commit description: it should be "... just highest possible divider
> 512".

Of course, I will do it.

Stefano

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de
=====================================================================

[U-Boot] [PATCH V2 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Stefano Babic]

From: Anatolij Gustschin <agust@denx.de>

The MXC SPI driver didn't calculate the SPI clock up to
now and just highest possible divider 512 for DATA
RATE in the control register. This results in very low
transfer rates.

The patch adds code to calculate and setup the SPI clock
frequency for transfers.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Stefano Babic <sbabic@denx.de>
---
Changes:

The patch is rebased on the current patches already sent for this driver
(support for MX35). Tested on a MX35 board.

Modified commit message as suggested by Anatolij

 drivers/spi/mxc_spi.c |   24 +++++++++++++++++++++++-
 1 files changed, 23 insertions(+), 1 deletions(-)

diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
index 0e42d41..32be7b0 100644
--- a/drivers/spi/mxc_spi.c
+++ b/drivers/spi/mxc_spi.c
@@ -71,6 +71,7 @@ static unsigned long spi_bases[] = {
 };
 
 #define spi_cfg	spi_cfg_mx3
+#define mxc_get_clock(x)	mx31_get_ipg_clk()
 
 #elif defined(CONFIG_MX51)
 #include <asm/arch/imx-regs.h>
@@ -201,15 +202,36 @@ void spi_cs_deactivate(struct spi_slave *slave)
 			      !(mxcs->ss_pol));
 }
 
+u32 get_cspi_div(u32 div)
+{
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		if (div <= (4 << i))
+			return i;
+	}
+	return i;
+}
+
 #if defined(CONFIG_MX31) || defined(CONFIG_MX35)
 static s32 spi_cfg_mx3(struct mxc_spi_slave *mxcs, unsigned int cs,
 		unsigned int max_hz, unsigned int mode)
 {
 	unsigned int ctrl_reg;
+	u32 clk_src;
+	u32 div;
+
+	clk_src = mxc_get_clock(MXC_CSPI_CLK);
+
+	div = clk_src / max_hz;
+	div = get_cspi_div(div);
+
+	debug("clk %d Hz, div %d, real clk %d Hz\n",
+		max_hz, div, clk_src / (4 << div));
 
 	ctrl_reg = MXC_CSPICTRL_CHIPSELECT(cs) |
 		MXC_CSPICTRL_BITCOUNT(MXC_CSPICTRL_MAXBITS) |
-		MXC_CSPICTRL_DATARATE(7) | /* FIXME: calculate data rate */
+		MXC_CSPICTRL_DATARATE(div) |
 		MXC_CSPICTRL_EN |
 #ifdef CONFIG_MX35
 		MXC_CSPICTRL_SSCTL |
-- 
1.7.1

[U-Boot] [PATCH V2 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Sergei Shtylyov]

Hello.

Stefano Babic wrote:

> From: Anatolij Gustschin <agust@denx.de>

> The MXC SPI driver didn't calculate the SPI clock up to
> now and just highest possible divider 512 for DATA
               ^
    I think "used" shouldn't have been ommitted here.

> RATE in the control register. This results in very low
> transfer rates.

> The patch adds code to calculate and setup the SPI clock
> frequency for transfers.

> Signed-off-by: Anatolij Gustschin <agust@denx.de>
> Signed-off-by: Stefano Babic <sbabic@denx.de>

WBR, Sergei

[U-Boot] [PATCH V2 2/2] SPI: mxc_spi: add SPI clock calculation and setup to the driver

[Stefano Babic]

On 01/18/2011 04:37 PM, Sergei Shtylyov wrote:
> Hello.
> 
> Stefano Babic wrote:
> 
>> From: Anatolij Gustschin <agust@denx.de>
> 
>> The MXC SPI driver didn't calculate the SPI clock up to
>> now and just highest possible divider 512 for DATA
>               ^
>    I think "used" shouldn't have been ommitted here.
> 

Right. I fix it.

Best regards,
Stefano Babic

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de
=====================================================================

[U-Boot] [PATCH 1/2] SPI: mxc_spi: fix swapping bug and add missing swapping in unaligned rx case

[Stefano Babic]

On 01/16/2011 07:17 PM, Anatolij Gustschin wrote:
> We need to shift only one time in each cycle in the swapping loop
> for unaligned tx case. Currently two byte shift operations are
> performed in each loop cycle causing zero gaps in the transmited
> data, so not all data scheduled for transmition is actually
> transmited.

Tested on a mx35pdk.

Tested-by: Stefano Babic <sbabic@denx.de>

Best regards,
Stefano Babic

-- 
=====================================================================
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: +49-8142-66989-0 Fax: +49-8142-66989-80  Email: office at denx.de
=====================================================================