[PATCH] phy: freescale: imx8m-pcie: Handle IMX8_PCIE_REFCLK_PAD_UNUSED

[Marek Vasut]

On 3/14/22 02:51, Hongxing Zhu wrote:
>> -----Original Message-----
>> From: Marek Vasut <marex at denx.de>
>> Sent: 2022年3月12日 9:38
>> To: linux-phy at lists.infradead.org
>> Cc: Marek Vasut <marex at denx.de>; Fabio Estevam <festevam at denx.de>;
>> Kishon Vijay Abraham I <kishon at ti.com>; Marcel Ziswiler
>> <marcel.ziswiler at toradex.com>; dl-linux-imx <linux-imx at nxp.com>; Peng Fan
>> <peng.fan at nxp.com>; Hongxing Zhu <hongxing.zhu at nxp.com>; Shawn Guo
>> <shawnguo at kernel.org>; Vinod Koul <vkoul at kernel.org>;
>> linux-arm-kernel at lists.infradead.org
>> Subject: [PATCH] phy: freescale: imx8m-pcie: Handle
>> IMX8_PCIE_REFCLK_PAD_UNUSED
>>
>> 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.
>>
>> Signed-off-by: Marek Vasut <marex at denx.de>
> Hi Marek:
> Thanks for your patch.
> I assume that you had tested this IMX8_PCIE_REFCLK_PAD_UNUSED option.

Yes

> The CLK_N/P pads are not connected on the tested board, right?

They are connected from MX8MP SoC to MiniPCIe slot.
There is no external clock source like on the EVK, the MX8MP internal 
PLL is the clock source.

> BTW, it's better to add the Fixes tag into the commit log.

Do you think this should be considered a bugfix ?