imx6 eSATA

[Shawn Guo]

Copy Richard who might be better to clarify.

Shawn

On Sat, Jan 18, 2014 at 06:44:27PM +0000, Russell King - ARM Linux wrote:
> So, I see we have AHCI support for SATA on the iMX6.  Great... but it
> doesn't work on the cubox-i, because the phy settings are wrong.
> 
> The Cubox-i requires GPR13 set to 0x0593A044 - I haven't decoded what
> this means yet, but it's different from the 0x0593E4A4 which is
> currently hard-coded into the driver (and I've independently tested
> that this is indeed required.)
> 
> So, there's presently no DT properties for this - given that these
> parameters would be board specific, it surprises me that this has not
> been thought about, and properties already generated, because now it
> means that we need to _add_ new properties to this driver.
> 
> Also, this PDDQ mode thing, which can't be recovered except by reset.
> This is another illustration why Linux is unfriendly - the thing can
> silently go into this power down mode which is irrecoverable without
> any messages being generated nor any hints how to avoid it - maybe
> this should also be a DT property, not just a command line option.
> 
> More importantly, maybe we should print a message when we discover
> that there's nothing connected and we're going to enter this mode -
> maybe something like this:
> 
> diff --git a/drivers/ata/ahci_imx.c b/drivers/ata/ahci_imx.c
> index 3e23e9941dad..0a1ae7213992 100644
> --- a/drivers/ata/ahci_imx.c
> +++ b/drivers/ata/ahci_imx.c
> @@ -77,6 +77,10 @@ static void ahci_imx_error_handler(struct ata_port *ap)
>  			!IMX6Q_GPR13_SATA_MPLL_CLK_EN);
>  	clk_disable_unprepare(imxpriv->sata_ref_clk);
>  	imxpriv->no_device = true;
> +
> +	dev_info(ap->dev, "no device, link disabled until next reset.\n");
> +	dev_info(ap->dev, "pass " MODULE_PARAM_PREFIX
> +		 ".hotplug=1 to enable link hotplug support\n");
>  }
>  
>  static struct ata_port_operations ahci_imx_ops = {
> 
> 
> -- 
> FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up.  Estimation
> in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad.
> Estimate before purchase was "up to 13.2Mbit".