[meta-freescale] i.MX6 - PCIe not detecting some devices in Linux 3.14.28

[Eric Bénard]

Hi Nikolay,

Le Thu, 21 May 2015 19:41:19 +0300,
Nikolay Dimitrov <picmaster at mail.bg> a écrit :
> On 05/21/2015 07:26 PM, ansaris wrote:
> > Hi,
> > We are using imx6Q custom platform based on sabresd platform. For our
> > development we are using Linux 3.14.28_1.0.0-GA BSP but initially we
> > used Linux 3.10.53_1.0.0-GA BSP.
> > We have seen that the pcie driver file is updated in Linux 3.14.28.
> >
> > The problem we are facing is, we have a PCIe device which is SSD SATA.
> > With Linux 3.14.28_1.0.0-GA BSP, the PCIe-SATA is not getting detected
> > and it is showing below error.
> >      imx6q-pcie 1ffc000.pcie: phy link never came up
> >      imx6q-pcie 1ffc000.pcie: Failed to bring link up!
> >      imx6q-pcie 1ffc000.pcie: failed to initialize host
> >      imx6q-pcie: probe of 1ffc000.pcie failed with error -22
> >
> > With Linux 3.10.53_1.0.0-GA BSP, the same PCIe-SATA is getting detected
> > and mounted as block device.
> > Here we have not changed any hardware. We just replaced the booting SD
> > card which contains Linux 3.10.53_1.0.0-GA BSP binaries.
> >
> > In addition, , we have checked with several PCIe devices (network PCIe
> > devices) with Linux 3.14.28_1.0.0-GA BSP. Only some of the PCIe devices
> > are getting detected.
> > Please note that, all the devices are getting detected in the Linux
> > 3.10.53_1.0.0-GA BSP.
> >
> > Please help us to resolve this issue.
> 
> Please clarify whether your device is PCIe or SATA - it can be only one
> of those, not both at the same time.
> 
FWIW newer M.2 boards directly expose a PCIe interface and embed a SATA
controler which (I believe) expose one drive but balances the load
between several SATA SSD to get better performances.
So the host only see a PCIe interface but the board has both PCIe and
SATA inside (and the host needs both PCIe and AHCI support) :
http://en.wikipedia.org/wiki/M.2
http://www.amazon.com/Samsung-XP941-512GB-AHCI-80mm/dp/B00JOSM3TK
http://www.bjorn3d.com/2015/03/480gb-hyperx-predator-m-2-pcie-ssd-shpm2280p2480g/
(M.2 SSD also exist with a SATA interface directly exposed but they have
a different keying on the connector to prevent the mismatch which is
possible with mSATA vs mPCIe).

Best regards,
Eric