Hi Arnd, Sinan > -----Original Message----- > From: Sinan Kaya [mailto:okaya@xxxxxxxxxxxxxx] > Sent: 08 February 2016 14:12 > To: Arnd Bergmann; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > Cc: Gabriele Paoloni; Lorenzo.Pieralisi@xxxxxxx; jcm@xxxxxxxxxx; > tn@xxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; Linuxarm; xuwei (O); linux- > kernel@xxxxxxxxxxxxxxx; linux-acpi@xxxxxxxxxxxxxxx; Wangzhou (B); > liudongdong (C); Guohanjun (Hanjun Guo); bhelgaas@xxxxxxxxxx; > zhangjukuo; Liguozhu (Kenneth); qiujiang > Subject: Re: [RFC PATCH 0/4] Add ACPI support for HiSilicon PCIe Host > Controllers > > On 2/8/2016 8:55 AM, Arnd Bergmann wrote: > > I haven't really followed what is going on with ACPI. Do you expect > > to see future machines come out that are not just implementing SBSA > > but that still need to run ACPI? I thought this was just a hack > > for some early machines that only run with ACPI but are not actually > > compliant. Well from our side (HiSilicon) we're trying to move away from non fully ECAM platforms, so from us in the long term I don't expect too many quirks, but I don't know about the other vendors. Obviously the reason why Tomasz implemented the quirks is to fit non fully ECAM HW and to allow custom HW init; this is why I thought better to have the ACPI version in the same dir as the DT (maybe we can create an ACPI sub-dir in drivers/pci/host ?) > > > > Arnd > > I agree. We shouldn't be playing with half-baked ACPI solutions. We > have seen > two variants already that claim to be ACPI compliant yet they do not > tie into > anything inside ACPICA. > > The correct route is to use Tomasz's ACPI PCI root bridge driver and > use the ACPI > framework. > > If a platform has quirks, Tomasz's patches allow vendors add quirks > too. > > The combination of PCI host bridge driver + ACPI hack is not right. If you look at my patchset you can see that I didn't do any hack, I just used the framework provided by Tomasz patchset. The discussion here is more about the code location for the quirks. Since the configuration read/write and the HW init sequences can be similar between the ACPI variant and DT variant I thought it make sense to have them in "drivers/pci/host" Thanks Gab > > -- > Sinan Kaya > Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, > Inc. > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a > Linux Foundation Collaborative Project -- 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
