[PATCH v4 1/2] ata: pata_at91.c bugfix for initial_timing initialisation

[PATCH v4 1/2] ata: pata_at91.c bugfix for initial_timing initialisation

[Igor Plyatov]

The "struct ata_timing" must contain 10 members, but ".dmack_hold" member was
forgotten for "initial_timing" initialisation. This patch fixes such a problem.

Signed-off-by: Igor Plyatov <plyatov@gmail.com>
---
 drivers/ata/pata_at91.c |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
index 0da0dcc..0267d54 100644
--- a/drivers/ata/pata_at91.c
+++ b/drivers/ata/pata_at91.c
@@ -49,8 +49,18 @@ struct at91_ide_info {
 	void __iomem *alt_addr;
 };
 
-static const struct ata_timing initial_timing =
-	{XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0};
+static const struct ata_timing initial_timing = {
+	.mode		= XFER_PIO_0,
+	.setup		= 70,
+	.act8b		= 290,
+	.rec8b		= 240,
+	.cyc8b		= 600,
+	.active		= 165,
+	.recover	= 150,
+	.dmack_hold	= 0,
+	.cycle		= 600,
+	.udma		= 0
+};
 
 static unsigned long calc_mck_cycles(unsigned long ns, unsigned long mck_hz)
 {
-- 
1.7.1

[PATCH v4 2/2] ata: pata_at91.c bugfix for high master clock

[Igor Plyatov]

The AT91SAM9 microcontrollers with master clock higher then 105 MHz
and PIO0, have overflow of the NCS_RD_PULSE value in the MSB. This
lead to "NCS_RD_PULSE" pulse longer then "NRD_CYCLE" pulse and driver
does not detect ATA device.

Signed-off-by: Igor Plyatov <plyatov@gmail.com>
---
 drivers/ata/pata_at91.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
index 0267d54..a5fdbdc 100644
--- a/drivers/ata/pata_at91.c
+++ b/drivers/ata/pata_at91.c
@@ -33,11 +33,12 @@
 
 
 #define DRV_NAME "pata_at91"
-#define DRV_VERSION "0.1"
+#define DRV_VERSION "0.2"
 
 #define CF_IDE_OFFSET	    0x00c00000
 #define CF_ALT_IDE_OFFSET   0x00e00000
 #define CF_IDE_RES_SIZE     0x08
+#define NCS_RD_PULSE_LIMIT  0x3f /* maximal value for pulse bitfields */
 
 struct at91_ide_info {
 	unsigned long mode;
@@ -119,6 +120,11 @@ static void set_smc_timing(struct device *dev,
 	/* (CS0, CS1, DIR, OE) <= (CFCE1, CFCE2, CFRNW, NCSX) timings */
 	ncs_read_setup = 1;
 	ncs_read_pulse = read_cycle - 2;
+	if (ncs_read_pulse > NCS_RD_PULSE_LIMIT) {
+		ncs_read_pulse = NCS_RD_PULSE_LIMIT;
+		dev_warn(dev, "ncs_read_pulse limited to maximal value %lu\n",
+			ncs_read_pulse);
+	}
 
 	/* Write timings same as read timings */
 	write_cycle = read_cycle;
-- 
1.7.1

Re: [PATCH v4 1/2] ata: pata_at91.c bugfix for initial_timing initialisation

[Sergei Shtylyov]

Hello.

Igor Plyatov wrote:

> The "struct ata_timing" must contain 10 members, but ".dmack_hold" member was
> forgotten for "initial_timing" initialisation. This patch fixes such a problem.

> Signed-off-by: Igor Plyatov <plyatov@gmail.com>
> ---
>  drivers/ata/pata_at91.c |   14 ++++++++++++--
>  1 files changed, 12 insertions(+), 2 deletions(-)

> diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
> index 0da0dcc..0267d54 100644
> --- a/drivers/ata/pata_at91.c
> +++ b/drivers/ata/pata_at91.c
> @@ -49,8 +49,18 @@ struct at91_ide_info {
>  	void __iomem *alt_addr;
>  };
>  
> -static const struct ata_timing initial_timing =
> -	{XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0};
> +static const struct ata_timing initial_timing = {
> +	.mode		= XFER_PIO_0,
> +	.setup		= 70,
> +	.act8b		= 290,
> +	.rec8b		= 240,
> +	.cyc8b		= 600,
> +	.active		= 165,
> +	.recover	= 150,
> +	.dmack_hold	= 0,
> +	.cycle		= 600,
> +	.udma		= 0
> +};

   There's no need to explicitly initialize to 0.

MBR, Sergei

Re: [PATCH v4 1/2] ata: pata_at91.c bugfix for initial_timing initialisation

[Igor Plyatov]

Hello Sergei!

> Hello.
> 
> Igor Plyatov wrote:
> 
> > The "struct ata_timing" must contain 10 members, but ".dmack_hold" member was
> > forgotten for "initial_timing" initialisation. This patch fixes such a problem.
> 
> > Signed-off-by: Igor Plyatov <plyatov@gmail.com>
> > ---
> >  drivers/ata/pata_at91.c |   14 ++++++++++++--
> >  1 files changed, 12 insertions(+), 2 deletions(-)
> 
> > diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
> > index 0da0dcc..0267d54 100644
> > --- a/drivers/ata/pata_at91.c
> > +++ b/drivers/ata/pata_at91.c
> > @@ -49,8 +49,18 @@ struct at91_ide_info {
> >  	void __iomem *alt_addr;
> >  };
> >  
> > -static const struct ata_timing initial_timing =
> > -	{XFER_PIO_0, 70, 290, 240, 600, 165, 150, 600, 0};
> > +static const struct ata_timing initial_timing = {
> > +	.mode		= XFER_PIO_0,
> > +	.setup		= 70,
> > +	.act8b		= 290,
> > +	.rec8b		= 240,
> > +	.cyc8b		= 600,
> > +	.active		= 165,
> > +	.recover	= 150,
> > +	.dmack_hold	= 0,
> > +	.cycle		= 600,
> > +	.udma		= 0
> > +};
> 
>    There's no need to explicitly initialize to 0.
> 
> MBR, Sergei

It's much better to explicitly initialise, then use old wrong code,
where .dmack_hold member was equal to 600.

Best regards!
--
Igor Plyatov