linux-phytec-fsl

MLK-13186-4 PCI: imx: enable external osc support

In order to pass the pcie gen2 compliance tests,
the external oscillator is mandatory required by
imx6 legacy platforms.
add the external osc support by this patch.
- pll6 should be set bypass mode.
- src of the pll6_bypass should be lvds_clk1
- adjust the swing/deemphase value
- re-configure the phy if the external 100Mhz
differential osc is used. Because that phy used
the 125Mhz before.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>