From: Bjorn Helgaas <helgaas@kernel.org>
To: "Kuppuswamy,
Sathyanarayanan" <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: bhelgaas@google.com, linux-pci@vger.kernel.org,
linux-kernel@vger.kernel.org, ashok.raj@intel.com
Subject: Re: [PATCH v8 2/5] ACPI/PCI: Ignore _OSC negotiation result if pcie_ports_native is set.
Date: Tue, 15 Sep 2020 17:20:33 -0500 [thread overview]
Message-ID: <20200915222033.GA1438273@bjorn-Precision-5520> (raw)
In-Reply-To: <badc377a-09f9-aabe-0b34-9f806da4b255@linux.intel.com>
On Sun, Sep 13, 2020 at 01:54:38PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> On 9/10/20 1:14 PM, Bjorn Helgaas wrote:
> > On Fri, Jul 24, 2020 at 08:58:53PM -0700, sathyanarayanan.kuppuswamy@linux.intel.com wrote:
> > > From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> > >
> > > pcie_ports_native is set only if user requests native handling
> > > of PCIe capabilities via pcie_port_setup command line option.
> > > User input takes precedence over _OSC based control negotiation
> > > result. So consider the _OSC negotiated result only if
> > > pcie_ports_native is unset.
> > >
> > > Also, since struct pci_host_bridge ->native_* members caches the
> > > ownership status of various PCIe capabilities, use them instead
> > > of distributed checks for pcie_ports_native.
> > >
> > > Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> > > ---
> > > drivers/acpi/pci_root.c | 61 ++++++++++++++++++++++++++-----
> > > drivers/pci/hotplug/pciehp_core.c | 2 +-
> > > drivers/pci/pci-acpi.c | 3 --
> > > drivers/pci/pcie/aer.c | 2 +-
> > > drivers/pci/pcie/portdrv_core.c | 9 ++---
> > > 5 files changed, 56 insertions(+), 21 deletions(-)
> > >
> > > diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> > > index f90e841c59f5..f8981d4e044d 100644
> > > --- a/drivers/acpi/pci_root.c
> > > +++ b/drivers/acpi/pci_root.c
> > > @@ -145,6 +145,17 @@ static struct pci_osc_bit_struct pci_osc_control_bit[] = {
> > > { OSC_PCI_EXPRESS_DPC_CONTROL, "DPC" },
> > > };
>
> > > + else
> > > + dev_warn(&bus->dev, "OS overrides %s firmware control",
> > > + get_osc_desc(OSC_PCI_EXPRESS_NATIVE_HP_CONTROL));
> >
> > There's got to be a way to write this more concisely. Maybe something
> > like this?
> >
> > #define OSC_OWNER(ctrl, bit, flag) \
> > if (!(ctrl & bit)) \
> > flag = 0;
> >
> > if (pcie_ports_native)
> > decode_osc_control(root, "OS forcibly taking over", ~0);
>
> BIT1 and BIT6 does not have PCIe dependency. And BIT7-31 are reserved.
> So we can't force all _OSC bits based on pcie_ports_native value.
> So, IM0, its better to handle PCIe features seperatly.
Yes, we may need to handle a few bits specially. But we need to
figure out a nicer-looking way of coding this. It's too cumbersome to
check pcie_ports_native and log a message for every _OSC bit
individually.
> > else {
> > ctrl = root->osc_control_set;
> > OSC_OWNER(ctrl, OSC_PCI_EXPRESS_AER_CONTROL, host_bridge->native_aer);
> > OSC_OWNER(ctrl, OSC_PCI_EXPRESS_PME_CONTROL, host_bridge->native_pme);
> > ...
> > }
>
>
> --
> Sathyanarayanan Kuppuswamy
> Linux Kernel Developer
next prev parent reply other threads:[~2020-09-15 22:20 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-25 3:58 [PATCH v8 0/5] Simplify PCIe native ownership detection logic sathyanarayanan.kuppuswamy
2020-07-25 3:58 ` [PATCH v8 1/5] PCI: Conditionally initialize host bridge native_* members sathyanarayanan.kuppuswamy
2020-09-10 19:49 ` Bjorn Helgaas
2020-09-10 21:00 ` Kuppuswamy, Sathyanarayanan
2020-09-13 20:49 ` Kuppuswamy, Sathyanarayanan
2020-09-15 22:17 ` Bjorn Helgaas
2020-09-16 2:30 ` Kuppuswamy, Sathyanarayanan
2020-07-25 3:58 ` [PATCH v8 2/5] ACPI/PCI: Ignore _OSC negotiation result if pcie_ports_native is set sathyanarayanan.kuppuswamy
2020-07-25 10:35 ` Andy Shevchenko
2020-09-10 20:14 ` Bjorn Helgaas
2020-09-13 20:54 ` Kuppuswamy, Sathyanarayanan
2020-09-15 22:20 ` Bjorn Helgaas [this message]
2020-09-16 2:33 ` Kuppuswamy, Sathyanarayanan
2020-07-25 3:58 ` [PATCH v8 3/5] ACPI/PCI: Ignore _OSC DPC negotiation result if pcie_ports_dpc_native " sathyanarayanan.kuppuswamy
2020-07-25 3:58 ` [PATCH v8 4/5] PCI/portdrv: Remove redundant pci_aer_available() check in DPC enable logic sathyanarayanan.kuppuswamy
2020-07-25 3:58 ` [PATCH v8 5/5] PCI/DPC: Move AER/DPC dependency checks out of DPC driver sathyanarayanan.kuppuswamy
2020-07-25 10:38 ` Andy Shevchenko
2020-08-27 18:22 ` [PATCH v8 0/5] Simplify PCIe native ownership detection logic Kuppuswamy, Sathyanarayanan
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