[U-Boot] [PATCH V3] mvsata_ide: adjust port init sequence

[Prafulla Wadaskar]

> -----Original Message-----
> From: u-boot-bounces at lists.denx.de 
> [mailto:u-boot-bounces at lists.denx.de] On Behalf Of Albert Aribaud
> Sent: Wednesday, September 08, 2010 11:01 PM
> To: u-boot at lists.denx.de
> Subject: [U-Boot] [PATCH V3] mvsata_ide: adjust port init sequence
> 
> mvsata_ide_initialize_port(): adjust init sequence (SStatus
> should be checked only after all writes to SControl) and
> return success/failure to ide_preinit().
> 
> Also, as some tests showed init durations in the hundreds
> of us, raise the time-out to 01 ms to be on the safe side.
> 
> Signed-off-by: Albert Aribaud <albert.aribaud at free.fr>
> ---
> PATCH HISTORY
> 
> V1	Initial patch.
> V2	Fixed wrong placement of comment.
> 	Fixed wrong description (was 01 ms, should have been 10).
> 	Added Signed-off-by.
> V3	Replaced return status values with symbolic names.
> 	Made error status values negative.
> 	Renamed 'tout' to 'timeleft' for clarity.
> 	Replaced ternary '?:' operator with '!' and if.
> 
> Patch was run through checkscript.pl with 0 errors and warnings.
> 
>  drivers/block/mvsata_ide.c |   42 
> +++++++++++++++++++++++++++++++++---------
>  1 files changed, 33 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/block/mvsata_ide.c b/drivers/block/mvsata_ide.c
> index 077b278..3d6993a 100644
> --- a/drivers/block/mvsata_ide.c
> +++ b/drivers/block/mvsata_ide.c
> @@ -91,29 +91,48 @@ struct mvsata_port_registers {
>  #define MVSATA_SSTATUS_DET_DEVCOMM		0x00000003
>  
>  /*
> + * Status codes to return to client callers. Currently, 
> callers ignore
> + * exact value and only care for zero or nonzero, so no need 
> to make this
> + * public, it is only #define'd for clarity.
> + * If/when standard negative codes are implemented in 
> U-boot, then these
> + * #defines should be moved to, or replaced by ones from, 
> the common list
> + * of status codes.
> + */
> +
> +#define MVSATA_STATUS_OK	0
> +#define MVSATA_STATUS_TIMEOUT	-1
> +
> +/*
>   * Initialize one MVSATAHC port: set SControl's IPM to 
> "always active"
>   * and DET to "reset", then wait for SStatus's DET to become 
> "device and
>   * comm ok" (or time out after 50 us if no device), then set 
> SControl's
>   * DET back to "no action".
>   */
>  
> -static void mvsata_ide_initialize_port(struct 
> mvsata_port_registers *port)
> +static int mvsata_ide_initialize_port(struct 
> mvsata_port_registers *port)
>  {
>  	u32 control;
>  	u32 status;
> -	u32 tout = 50; /* wait at most 50 us for SATA reset to 
> complete */
> +	u32 timeleft = 10000; /* wait at most 10 ms for SATA 
> reset to complete */
>  
> +	/* Set control IPM to 3 (no low power) and DET to 1 
> (initialize) */
>  	control = readl(&port->scontrol);
>  	control = (control & ~MVSATA_SCONTROL_MASK) | MVSATA_PORT_INIT;
>  	writel(control, &port->scontrol);
> -	while (--tout) {
> +	/* Toggle control DET back to 0 (normal operation) */
> +	control = (control & ~MVSATA_SCONTROL_MASK) | MVSATA_PORT_USE;
> +	writel(control, &port->scontrol);
> +	/* wait for status DET to become 3 (device and 
> communication OK) */
> +	while (--timeleft) {
>  		status = readl(&port->sstatus) & 
> MVSATA_SSTATUS_DET_MASK;
>  		if (status == MVSATA_SSTATUS_DET_DEVCOMM)
>  			break;
>  		udelay(1);
>  	}
> -	control = (control & ~MVSATA_SCONTROL_MASK) | MVSATA_PORT_USE;
> -	writel(control, &port->scontrol);
> +	/* return success or time-out error depending on time left */
> +	if (!timeleft)
> +		return MVSATA_STATUS_TIMEOUT;
> +	return MVSATA_STATUS_OK;
>  }
>  
>  /*
> @@ -123,18 +142,23 @@ static void 
> mvsata_ide_initialize_port(struct mvsata_port_registers *port)
>  
>  int ide_preinit(void)
>  {
> +	int status;
>  	/* Enable ATA port 0 (could be SATA port 0 or 1) if declared */
>  #if defined(CONFIG_SYS_ATA_IDE0_OFFSET)
> -	mvsata_ide_initialize_port(
> +	status = mvsata_ide_initialize_port(
>  		(struct mvsata_port_registers *)
>  		(CONFIG_SYS_ATA_BASE_ADDR + 
> CONFIG_SYS_ATA_IDE0_OFFSET));
> +	if (status)
> +		return status;
>  #endif
>  	/* Enable ATA port 1 (could be SATA port 0 or 1) if declared */
>  #if defined(CONFIG_SYS_ATA_IDE1_OFFSET)
> -	mvsata_ide_initialize_port(
> +	status = mvsata_ide_initialize_port(
>  		(struct mvsata_port_registers *)
>  		(CONFIG_SYS_ATA_BASE_ADDR + 
> CONFIG_SYS_ATA_IDE1_OFFSET));
> +	if (status)
> +		return status;
>  #endif
> -	/* return 0 as we always succeed */
> -	return 0;
> +	/* return success if all ports initializations succeeded */
> +	return MVSATA_STATUS_OK;
>  }

Ack

Regards..
Prafulla . .