On Tue, Aug 20, 2019 at 07:28:37AM +0000, Z.q. Hou wrote:
> From: Hou Zhiqiang <Zhiqiang.Hou@xxxxxxx>
>
> On FSL Layerscape SoCs, the number of lanes assigned to PCIe
> controller is not fixed, it is determined by the selected
> SerDes protocol. The current num-lanes indicates the max lanes
> PCIe controller can support up to, instead of the lanes assigned
> to the PCIe controller. This can result in PCIe link training fail
> after hot-reset.
>
> Hou Zhiqiang (4):
> dt-bindings: PCI: designware: Remove the num-lanes from Required
> properties
> PCI: dwc: Return directly when num-lanes is not found
> ARM: dts: ls1021a: Remove num-lanes property from PCIe nodes
> arm64: dts: fsl: Remove num-lanes property from PCIe nodes
>
> Documentation/devicetree/bindings/pci/designware-pcie.txt | 1 -
> arch/arm/boot/dts/ls1021a.dtsi | 2 --
> arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi | 1 -
> arch/arm64/boot/dts/freescale/fsl-ls1043a.dtsi | 3 ---
> arch/arm64/boot/dts/freescale/fsl-ls1046a.dtsi | 6 ------
> arch/arm64/boot/dts/freescale/fsl-ls1088a.dtsi | 3 ---
> arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi | 4 ----
> drivers/pci/controller/dwc/pcie-designware.c | 6 ++++--
> 8 files changed, 4 insertions(+), 22 deletions(-)
What a mess.
I am going to apply these but first if anyone can explain to
me what commit 907fce090253 was _supposed_ to to I would
be grateful, I read it multiple times but I still have not
understood it. This series does the right thing but why things
are they way they are in the mainline honestly I have no
idea, this does not make any sense in the slightest:
ret = of_property_read_u32(np, "num-lanes", &lanes);
if (ret)
lanes = 0;
/* Set the number of lanes */
val = dw_pcie_readl_dbi(pci, PCIE_PORT_LINK_CONTROL);
val &= ~PORT_LINK_MODE_MASK;
switch (lanes) {
case 1:
val |= PORT_LINK_MODE_1_LANES;
break;
case 2:
val |= PORT_LINK_MODE_2_LANES;
break;
case 4:
val |= PORT_LINK_MODE_4_LANES;
break;
case 8:
val |= PORT_LINK_MODE_8_LANES;
break;
default:
dev_err(pci->dev, "num-lanes %u: invalid value\n", lanes);
return;
}
why do we need to set lanes to 0 if num-lanes is not present ? To print
an error message ?
I really do not understand this code.
Lorenzo
