Messages in this thread | | | Subject | Re: [PATCH v3 2/3] x86/platform/p2sb: New Primary to Sideband bridge support driver for Intel SOC's | From | Andy Shevchenko <> | Date | Mon, 13 Jun 2016 16:54:31 +0300 |
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On Thu, 2016-06-09 at 17:05 +0300, Mika Westerberg wrote: > On Tue, Jun 07, 2016 at 02:55:52PM +0800, Tan Jui Nee wrote: > > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > > > There is already one and at least one more user coming which > > require an access to Primary to Sideband bridge (P2SB) in order > > to get IO or MMIO bar hidden by BIOS. > > Create a driver to access P2SB for x86 devices. > > > > Signed-off-by: Yong, Jonathan <jonathan.yong@intel.com> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > --- > > arch/x86/Kconfig | 14 ++++++ > > arch/x86/include/asm/p2sb.h | 27 +++++++++++ > > arch/x86/platform/intel/Makefile | 1 + > > arch/x86/platform/intel/p2sb.c | 99 > > ++++++++++++++++++++++++++++++++++++++++ > > 4 files changed, 141 insertions(+) > > create mode 100644 arch/x86/include/asm/p2sb.h > > create mode 100644 arch/x86/platform/intel/p2sb.c > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index 2dc18605..589045e 100644 > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -606,6 +606,20 @@ config IOSF_MBI_DEBUG > > > > If you don't require the option or are in doubt, say N. > > > > +config X86_INTEL_NON_ACPI > > + bool "Enable support non-ACPI Intel platforms" > > + select PINCTRL > > + ---help--- > > + Select this option to enables MMIO BAR access over the > > P2SB for > > + non-ACPI Intel SoC platforms. This driver uses the P2SB > > hide/unhide > > + mechanism cooperatively to pass the PCI BAR address to > > the platform > > + driver, currently GPIO on the following SoC products. > > + - Apollo Lake > > Why do we need Kconfig option for this?
In one of previous review I was wondering how we could not to build this at all. I don't like this option either.
> > I think better is to make P2SB available on CPUs which have one, and > that can be detected runtime. If P2SB is not available then p2sb_bar() > returns -ENODEV.
Would work to me, though still the same question: is it possible to avoid building it on even most of Intel platforms, since there, I assume, will be not many users of the module?
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Andy Shevchenko <andriy.shevchenko@linux.intel.com> Intel Finland Oy
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