On Thu, Apr 17, 2014 at 12:02:26AM +0100, Russell King - ARM Linux wrote: > On Wed, Apr 16, 2014 at 11:57:21PM +0100, Russell King - ARM Linux wrote: > > On Wed, Apr 16, 2014 at 05:46:47PM -0500, Rob Herring wrote: > > > On Wed, Apr 16, 2014 at 3:43 AM, Russell King > > > <rmk+kernel@xxxxxxxxxxxxxxxx> wrote: > > > > Spread-spectrum doesn't work with Cubox-i hardware, so we have to > > > > disable this feature. Add a DT property so that platforms can > > > > indicate that this feature should not be enabled. > > > > > > This is for spread-spectrum tx or rx? Transmit SS is optional to > > > support, but the receiver must support SS. Otherwise random drives > > > won't work which makes for a good user experience. Is this really a > > > board quirk rather than a Si issue? > > > > No idea. This bit controls clock generation, and one reason given to > > disable it is if the reference clock being supplied is already spread > > spectrum. I don't think that applies here. It doesn't say which > > clock(s) this is applied to - I would guess it's the transmit clock. > > > > All I know is that with SS enabled, the drive is not detected, and > > SolidRun's original port disables SS. Disabling SS allows the external > > drive to be detected. > > > > I have no capability to check the eye pattern, so I've no idea if > > there's a problem with the electrical setup which stops SS from > > working. All I know is with the parameters I give here (which are > > those which SolidRun's original port uses) and with SS disabled, > > it works. > > I'll correct that - it _is_ detected with SS enabled, but things go > awry very quickly with errors, which then result in corrupted IDENTIFY > responses, the link dropping back to 1.5Gbps, more errors and corruption > and eventually the SATA layer gives up and declares the port dead. Rob, Can I take your lack of reply on this as meaning that you don't have any objections against these new DT properties for this driver - if so, can I have your ack for these properties please? -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
