Am Samstag, 21. Mai 2016, 11:55:35 schrieb Shawn Lin: > On 2016/5/20 19:20, Heiko Stuebner wrote: > > Hi Shawn, > > > > Am Freitag, 20. Mai 2016, 18:29:06 schrieb Shawn Lin: > >> This patch add some required and optional properties for Rockchip > >> PCIe controller. Also we add a example for how to use it. > >> > >> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> > >> > >> --- [...] > >> +- msi-parent: Link to the hardware entity that serves as the Message > >> +- pinctrl-names : The pin control state names > >> +- pinctrl-0: The "default" pinctrl state > > > > I'm not sure if pinctrl-properties need to be described when you don't > > need special handling in the form of additional pin states. The pcie > > part does not do any pin-handling of its own. > > We need it in prevention of any firmwares change the default state > of #CLKREQ which is useful for ASPM. Also we have a backup pin for > clkreqn called clkreqnb, which should be taken more consideration since > when refering to any one of these two, pinctrl should configure the > bit[14] of GRF_SOC_CON7 automatically. But it is unfortunately beyound > the implementation of pinctrl-rk3399. > > BTW, I don't know if we wanna support this action inside the pinctrl > code? The TRM says for me for that bit only "pcie_clkreq_sel port control" and that naming really suggests that it is a property of the pcie controller, not the generic pinctrl. So if this needs to be touched the pcie controller needs to do it. > >> +- interrupt-map-mask and interrupt-map: standard PCI properties > >> +- interrupt-controller: identifies the node as an interrupt controller > >> + > >> +Optional Property: > >> +- ep-gpios: contain the entry for pre-reset gpio > >> +- num-lanes: number of lanes to use > >> +- assigned-clocks, assigned-clock-parents and assigned-clock-rates: > >> standard + clock bindings. See ../clock/clock-bindings.txt > > > > Again that (assigned-clocks handling) is not actual part of the pci- > > controllers actions, but other parts and also described already > > elsewhere. > Basically it does. But this is an alternative choice for pcie-phy to > generate the ref_clk. When we want 100MHz src clk for PLL inside the > pcie-phy，we should add them, otherwise it's taken from xin 24MHz. > > This is useful for SI testing or some others special cases. So should we > add it as an option and leave a sample here? What I meant was that while clock handling is important when looking at the whole system, the pcie controller itself does only care that it gets a clock, but not that much where you get it from. So while assigned-clocks has its place in the real devicetree, I don't think it is an element of the actual pcie-controller binding. Heiko -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
