[PATCH 0/2] PCI: amlogic: Make PCIe working reliably on AXG platforms

[Remi Pommarel <repk@triplefau.lt>]

PCIe device probing failures have been seen on some AXG platforms and were
due to unreliable clock signal output. Setting HHI_MIPI_CNTL0[26] bit
solved the problem. After being contacted about this, vendor reported that
this bit was linked to PCIe PLL CML output.

This serie adds a way to set this bit through AXG clock gating logic.
Platforms having this kind of issue could make use of this gating by
applying a patch to their devicetree similar to:

                clocks = <&clkc CLKID_USB
                        &clkc CLKID_MIPI_ENABLE
                        &clkc CLKID_PCIE_A
-                       &clkc CLKID_PCIE_CML_EN0>;
+                       &clkc CLKID_PCIE_CML_EN0
+                       &clkc CLKID_PCIE_PLL_CML_ENABLE>;
                clock-names = "pcie_general",
                                "pcie_mipi_en",
                                "pcie",
-                               "port";
+                               "port",
+                               "pll_cml_en";
                resets = <&reset RESET_PCIE_PHY>,
                        <&reset RESET_PCIE_A>,
                        <&reset RESET_PCIE_APB>;


Remi Pommarel (2):
  clk: meson: axg: add pcie pll cml gating
  PCI: amlogic: Use PCIe pll gate when available

 drivers/clk/meson/axg.c                | 3 +++
 drivers/clk/meson/axg.h                | 2 +-
 drivers/pci/controller/dwc/pci-meson.c | 5 +++++
 include/dt-bindings/clock/axg-clkc.h   | 1 +
 4 files changed, 10 insertions(+), 1 deletion(-)

-- 
2.24.0