The 'fsl,refclk-pad-mode' DT property used to select clock source for
PCIe PHY can have either of three values, IMX8_PCIE_REFCLK_PAD_INPUT,
IMX8_PCIE_REFCLK_PAD_OUTPUT, IMX8_PCIE_REFCLK_PAD_UNUSED. The first
two options are handled correctly by the driver, the last one is not,
this patch implements support for the last option.
The IMX8_PCIE_REFCLK_PAD_INPUT means PCIE_RESREF is PHY clock input,
the IMX8_PCIE_REFCLK_PAD_OUTPUT means PHY clock are sourced from SoC
internal PLL and output to PCIE_RESREF external IO pin. The last
IMX8_PCIE_REFCLK_PAD_UNUSED is a combination of previous two, PHY
clock are sourced from SoC internal PLL and not output anywhere.
Reviewed-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@denx.de>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
To: linux-phy@lists.infradead.org
Link: https://lore.kernel.org/r/20220413140710.10074-1-marex@denx.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
f7f9abc5ea