Hi Marek, On Wed, Oct 24, 2018 at 05:20:56PM +0200, Marek Behún wrote: > Add code to do a warm reset on the PHY and PCIE cores and if PERSTN GPIO > is specified in device tree (as reset-gpio), also reset the card. > > The reset-gpio is inspired by what is done in U-Boot and linux-marvell, > and is not final version: I am hoping this can be done via a PCIe register > rather than GPIO - bit 3 of CTRL_WARM_RESET_REG register (which is added > by this patch) is called PERSTN_GPIO_EN (Enable PERSTN from GPIO) and > I think this is the right register, but manipulating this register did > not have any effect on the PERSTN pin, even when pinctrl was correctly set. > > I asked Marvell about this and am awaiting their reply. > > The reset-gpio is needed for Compex 5 GHz wifi card model WLE900VX. Without > this patch the PCIe link never comes up in kernel (although U-Boot pci > command was able to enumerate the card). > > What is weird is that the link does not come up for this card when > pci-aardvark driver is probed in U-Boot. I haven't yet had time to discover > the problem there. My temporary solution is to compile out the pci-aardvark > driver from U-Boot. > > This patch is based on 4.14 kernel. Thanks for your research and the patch! As I'm sure you know, this would have to be applied to the latest kernel, e.g., v4.20-rc1 (when that comes out in about 10 days), so the best place to test it would be v4.19 + this patch, or v4.20-rc1 + this patch. After it's applied to the master branch, it's possible it could be backported to stable kernels if appropriate. > If you have time, please try it with some PCIe cards and let me know if they > work correctly. > > Signed-off-by: Marek Behún <marek.behun@xxxxxx> > Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > Cc: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx> > Cc: Bjorn Helgaas <helgaas@xxxxxxxxxx> > Cc: linux-pci@xxxxxxxxxxxxxxx > Cc: Antoine Ténart <antoine.tenart@xxxxxxxxxxxxxxxxxx> > Cc: Grégory Clement <gregory.clement@xxxxxxxxxxxxxxxxxx> > Cc: Miquèl Raynal <miquel.raynal@xxxxxxxxxxxxxxxxxx> > Cc: Victor Gu <xigu@xxxxxxxxxxx> Nit: some of the CC lines above have extra spaces.
