[PATCH v8 0/2] Add the iMX8MP PCIe support

[Richard Zhu]

Based on the 6.0-rc1 of the pci/next branch. 
This series adds the i.MX8MP PCIe support and tested on i.MX8MP
EVK board when one PCIe NVME device is used.

- i.MX8MP PCIe has reversed initial PERST bit value refer to i.MX8MQ/i.MX8MM.
  Add the PHY PERST explicitly for i.MX8MP PCIe PHY.
- Add the i.MX8MP PCIe PHY support in the i.MX8M PCIe PHY driver.
  And share as much as possible codes with i.MX8MM PCIe PHY.
- Add the i.MX8MP PCIe support in binding document, DTS files, and PCIe
  driver.

Main changes v7-->v8:
- Add the Reviewed-by tag, no other changes.
  Only two patches in v8, Since the other patches had been merged by
  Philipp/Shawn/Lorenzo.

Main changes v6-->v7:
- Add "Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>" into first three
  patches.
- Use "const *char" to replace the static allocation.

Main changes v5-->v6:
- To avoid code duplication when find the gpr syscon regmap, add the
  gpr compatible into the drvdata.
- Add one missing space before one curly brace in 3/7 of v5 series.
- 4/7 of v5 had been applied by Phillipp, thanks. For ease of tests, still
  keep it in v6.

Main changes v4-->v5:
- Use Lucas' approach, let blk-ctrl driver do the hsio-mix resets.
- Fetch the iomuxc-gpr regmap by the different phandles.

Main changes v3-->v4:
- Regarding Phillipp's suggestions, add fix tag into the first commit.
- Add Reviewed and Tested tags.

Main changes v2-->v3:
- Fix the schema checking error in the PHY dt-binding patch.
- Inspired by Lucas, the PLL configurations might not required when
  external OSC is used as PCIe referrence clock. It's true. Remove all
  the HSIO PLL bit manipulations, and PCIe works fine on i.MX8MP EVK board
  with one NVME device is used.
- Drop the #4 patch of v2, since it had been applied by Rob.

Main changes v1-->v2:
- It's my fault forget including Vinod, re-send v2 after include Vinod
  and linux-phy@xxxxxxxxxxxxxxxxxxx.
- List the basements of this patch-set. The branch, codes changes and so on.
- Clean up some useless register and bit definitions in #3 patch.

[PATCH v8 1/2] dt-binding: phy: Add iMX8MP PCIe PHY binding
[PATCH v8 2/2] phy: freescale: imx8m-pcie: Add i.MX8MP PCIe PHY