diff mbox series

[v8,2/5] ACPI/PCI: Ignore _OSC negotiation result if pcie_ports_native is set.

Message ID ba80aa1cab7d244730c5abd48f3036bf527578cc.1595649348.git.sathyanarayanan.kuppuswamy@linux.intel.com
State New
Headers show
Series Simplify PCIe native ownership detection logic | expand

Commit Message

Kuppuswamy Sathyanarayanan July 25, 2020, 3:58 a.m. UTC 
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(-)

Comments

Andy Shevchenko July 25, 2020, 10:35 a.m. UTC | #1 
On Sat, Jul 25, 2020 at 7:01 AM
<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

the user

> 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.

...

> +static char *get_osc_desc(u32 bit)
> +{

> +       int i = 0;

Unneeded assignment.

> +       for (i = 0; i < ARRAY_SIZE(pci_osc_control_bit); i++)
> +               if (bit == pci_osc_control_bit[i].bit)
> +                       return pci_osc_control_bit[i].desc;
> +
> +       return NULL;
> +}

...

>         host_bridge = to_pci_host_bridge(bus->bridge);
> -       if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
> -               host_bridge->native_pcie_hotplug = 0;
> +       if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)) {
> +               if (!pcie_ports_native)
> +                       host_bridge->native_pcie_hotplug = 0;
> +               else

> +                       dev_warn(&bus->dev, "OS overrides %s firmware control",

pci_warn() ?

> +                       get_osc_desc(OSC_PCI_EXPRESS_NATIVE_HP_CONTROL));
> +       }
> +

>         if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
>                 host_bridge->native_shpc_hotplug = 0;

Group them in the same way you did in the previous patch.

> -       if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
> -               host_bridge->native_aer = 0;
> -       if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
> -               host_bridge->native_pme = 0;
> -       if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
> -               host_bridge->native_ltr = 0;
> -       if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
> -               host_bridge->native_dpc = 0;
> +
> +       if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL)) {

> +               if (!pcie_ports_native)
> +                       host_bridge->native_aer = 0;
> +               else
> +                       dev_warn(&bus->dev, "OS overrides %s firmware control",
> +                       get_osc_desc(OSC_PCI_EXPRESS_AER_CONTROL));

Looks like a lot of duplication here. Perhaps split out a helper ?

> +       }
Bjorn Helgaas Sept. 10, 2020, 8:14 p.m. UTC | #2 
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" },
>  };
>  
> +static char *get_osc_desc(u32 bit)
> +{
> +	int i = 0;
> +
> +	for (i = 0; i < ARRAY_SIZE(pci_osc_control_bit); i++)
> +		if (bit == pci_osc_control_bit[i].bit)
> +			return pci_osc_control_bit[i].desc;
> +
> +	return NULL;
> +}
> +
>  static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
>  			    struct pci_osc_bit_struct *table, int size)
>  {
> @@ -914,18 +925,48 @@ struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
>  		goto out_release_info;
>  
>  	host_bridge = to_pci_host_bridge(bus->bridge);
> -	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
> -		host_bridge->native_pcie_hotplug = 0;
> +	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)) {
> +		if (!pcie_ports_native)
> +			host_bridge->native_pcie_hotplug = 0;
> +		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);
  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);
    ...
  }

> +	}
> +
>  	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
>  		host_bridge->native_shpc_hotplug = 0;
> -	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
> -		host_bridge->native_aer = 0;
> -	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
> -		host_bridge->native_pme = 0;
> -	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
> -		host_bridge->native_ltr = 0;
> -	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
> -		host_bridge->native_dpc = 0;
> +
> +	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL)) {
> +		if (!pcie_ports_native)
> +			host_bridge->native_aer = 0;
> +		else
> +			dev_warn(&bus->dev, "OS overrides %s firmware control",
> +			get_osc_desc(OSC_PCI_EXPRESS_AER_CONTROL));
> +	}
> +
> +	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL)) {
> +		if (!pcie_ports_native)
> +			host_bridge->native_pme = 0;
> +		else
> +			dev_warn(&bus->dev, "OS overrides %s firmware control",
> +			get_osc_desc(OSC_PCI_EXPRESS_PME_CONTROL));
> +	}
> +
> +	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL)) {
> +		if (!pcie_ports_native)
> +			host_bridge->native_ltr = 0;
> +		else
> +			dev_warn(&bus->dev, "OS overrides %s firmware control",
> +			get_osc_desc(OSC_PCI_EXPRESS_LTR_CONTROL));
> +	}
> +
> +	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL)) {
> +		if (!pcie_ports_native)
> +			host_bridge->native_dpc = 0;
> +		else
> +			dev_warn(&bus->dev, "OS overrides %s firmware control",
> +			get_osc_desc(OSC_PCI_EXPRESS_DPC_CONTROL));
> +	}
>  
>  	/*
>  	 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
> diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
> index bf779f291f15..5fc999bf6f1b 100644
> --- a/drivers/pci/hotplug/pciehp_core.c
> +++ b/drivers/pci/hotplug/pciehp_core.c
> @@ -255,7 +255,7 @@ static bool pme_is_native(struct pcie_device *dev)
>  	const struct pci_host_bridge *host;
>  
>  	host = pci_find_host_bridge(dev->port->bus);
> -	return pcie_ports_native || host->native_pme;
> +	return host->native_pme;

I love this part!

>  }
>  
>  static void pciehp_disable_interrupt(struct pcie_device *dev)
> diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
> index 7224b1e5f2a8..e09589571a9d 100644
> --- a/drivers/pci/pci-acpi.c
> +++ b/drivers/pci/pci-acpi.c
> @@ -800,9 +800,6 @@ bool pciehp_is_native(struct pci_dev *bridge)
>  	if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
>  		return false;
>  
> -	if (pcie_ports_native)
> -		return true;
> -
>  	host = pci_find_host_bridge(bridge->bus);
>  	return host->native_pcie_hotplug;
>  }
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index 3acf56683915..d663bd9c7257 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -219,7 +219,7 @@ int pcie_aer_is_native(struct pci_dev *dev)
>  	if (!dev->aer_cap)
>  		return 0;
>  
> -	return pcie_ports_native || host->native_aer;
> +	return host->native_aer;
>  }
>  
>  int pci_enable_pcie_error_reporting(struct pci_dev *dev)
> diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
> index 50a9522ab07d..ccd5e0ce5605 100644
> --- a/drivers/pci/pcie/portdrv_core.c
> +++ b/drivers/pci/pcie/portdrv_core.c
> @@ -208,8 +208,7 @@ static int get_port_device_capability(struct pci_dev *dev)
>  	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
>  	int services = 0;
>  
> -	if (dev->is_hotplug_bridge &&
> -	    (pcie_ports_native || host->native_pcie_hotplug)) {
> +	if (dev->is_hotplug_bridge && host->native_pcie_hotplug) {
>  		services |= PCIE_PORT_SERVICE_HP;
>  
>  		/*
> @@ -221,8 +220,7 @@ static int get_port_device_capability(struct pci_dev *dev)
>  	}
>  
>  #ifdef CONFIG_PCIEAER
> -	if (dev->aer_cap && pci_aer_available() &&
> -	    (pcie_ports_native || host->native_aer)) {
> +	if (dev->aer_cap && pci_aer_available() && host->native_aer) {
>  		services |= PCIE_PORT_SERVICE_AER;
>  
>  		/*
> @@ -238,8 +236,7 @@ static int get_port_device_capability(struct pci_dev *dev)
>  	 * Event Collectors can also generate PMEs, but we don't handle
>  	 * those yet.
>  	 */
> -	if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT &&
> -	    (pcie_ports_native || host->native_pme)) {
> +	if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT && host->native_pme) {
>  		services |= PCIE_PORT_SERVICE_PME;
>  
>  		/*
> -- 
> 2.17.1
>
Kuppuswamy Sathyanarayanan Sept. 13, 2020, 8:54 p.m. UTC | #3 
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.
>    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);
>      ...
>    }
Bjorn Helgaas Sept. 15, 2020, 10:20 p.m. UTC | #4 
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
Kuppuswamy Sathyanarayanan Sept. 16, 2020, 2:33 a.m. UTC | #5 
On 9/15/20 3:20 PM, Bjorn Helgaas wrote:
> 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.
ok. Let me check how to simplify it.
> 
>>>     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
diff mbox series

Patch

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" },
 };
 
+static char *get_osc_desc(u32 bit)
+{
+	int i = 0;
+
+	for (i = 0; i < ARRAY_SIZE(pci_osc_control_bit); i++)
+		if (bit == pci_osc_control_bit[i].bit)
+			return pci_osc_control_bit[i].desc;
+
+	return NULL;
+}
+
 static void decode_osc_bits(struct acpi_pci_root *root, char *msg, u32 word,
 			    struct pci_osc_bit_struct *table, int size)
 {
@@ -914,18 +925,48 @@  struct pci_bus *acpi_pci_root_create(struct acpi_pci_root *root,
 		goto out_release_info;
 
 	host_bridge = to_pci_host_bridge(bus->bridge);
-	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
-		host_bridge->native_pcie_hotplug = 0;
+	if (!(root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)) {
+		if (!pcie_ports_native)
+			host_bridge->native_pcie_hotplug = 0;
+		else
+			dev_warn(&bus->dev, "OS overrides %s firmware control",
+			get_osc_desc(OSC_PCI_EXPRESS_NATIVE_HP_CONTROL));
+	}
+
 	if (!(root->osc_control_set & OSC_PCI_SHPC_NATIVE_HP_CONTROL))
 		host_bridge->native_shpc_hotplug = 0;
-	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL))
-		host_bridge->native_aer = 0;
-	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL))
-		host_bridge->native_pme = 0;
-	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL))
-		host_bridge->native_ltr = 0;
-	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL))
-		host_bridge->native_dpc = 0;
+
+	if (!(root->osc_control_set & OSC_PCI_EXPRESS_AER_CONTROL)) {
+		if (!pcie_ports_native)
+			host_bridge->native_aer = 0;
+		else
+			dev_warn(&bus->dev, "OS overrides %s firmware control",
+			get_osc_desc(OSC_PCI_EXPRESS_AER_CONTROL));
+	}
+
+	if (!(root->osc_control_set & OSC_PCI_EXPRESS_PME_CONTROL)) {
+		if (!pcie_ports_native)
+			host_bridge->native_pme = 0;
+		else
+			dev_warn(&bus->dev, "OS overrides %s firmware control",
+			get_osc_desc(OSC_PCI_EXPRESS_PME_CONTROL));
+	}
+
+	if (!(root->osc_control_set & OSC_PCI_EXPRESS_LTR_CONTROL)) {
+		if (!pcie_ports_native)
+			host_bridge->native_ltr = 0;
+		else
+			dev_warn(&bus->dev, "OS overrides %s firmware control",
+			get_osc_desc(OSC_PCI_EXPRESS_LTR_CONTROL));
+	}
+
+	if (!(root->osc_control_set & OSC_PCI_EXPRESS_DPC_CONTROL)) {
+		if (!pcie_ports_native)
+			host_bridge->native_dpc = 0;
+		else
+			dev_warn(&bus->dev, "OS overrides %s firmware control",
+			get_osc_desc(OSC_PCI_EXPRESS_DPC_CONTROL));
+	}
 
 	/*
 	 * Evaluate the "PCI Boot Configuration" _DSM Function.  If it
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index bf779f291f15..5fc999bf6f1b 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -255,7 +255,7 @@  static bool pme_is_native(struct pcie_device *dev)
 	const struct pci_host_bridge *host;
 
 	host = pci_find_host_bridge(dev->port->bus);
-	return pcie_ports_native || host->native_pme;
+	return host->native_pme;
 }
 
 static void pciehp_disable_interrupt(struct pcie_device *dev)
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 7224b1e5f2a8..e09589571a9d 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -800,9 +800,6 @@  bool pciehp_is_native(struct pci_dev *bridge)
 	if (!(slot_cap & PCI_EXP_SLTCAP_HPC))
 		return false;
 
-	if (pcie_ports_native)
-		return true;
-
 	host = pci_find_host_bridge(bridge->bus);
 	return host->native_pcie_hotplug;
 }
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 3acf56683915..d663bd9c7257 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -219,7 +219,7 @@  int pcie_aer_is_native(struct pci_dev *dev)
 	if (!dev->aer_cap)
 		return 0;
 
-	return pcie_ports_native || host->native_aer;
+	return host->native_aer;
 }
 
 int pci_enable_pcie_error_reporting(struct pci_dev *dev)
diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c
index 50a9522ab07d..ccd5e0ce5605 100644
--- a/drivers/pci/pcie/portdrv_core.c
+++ b/drivers/pci/pcie/portdrv_core.c
@@ -208,8 +208,7 @@  static int get_port_device_capability(struct pci_dev *dev)
 	struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
 	int services = 0;
 
-	if (dev->is_hotplug_bridge &&
-	    (pcie_ports_native || host->native_pcie_hotplug)) {
+	if (dev->is_hotplug_bridge && host->native_pcie_hotplug) {
 		services |= PCIE_PORT_SERVICE_HP;
 
 		/*
@@ -221,8 +220,7 @@  static int get_port_device_capability(struct pci_dev *dev)
 	}
 
 #ifdef CONFIG_PCIEAER
-	if (dev->aer_cap && pci_aer_available() &&
-	    (pcie_ports_native || host->native_aer)) {
+	if (dev->aer_cap && pci_aer_available() && host->native_aer) {
 		services |= PCIE_PORT_SERVICE_AER;
 
 		/*
@@ -238,8 +236,7 @@  static int get_port_device_capability(struct pci_dev *dev)
 	 * Event Collectors can also generate PMEs, but we don't handle
 	 * those yet.
 	 */
-	if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT &&
-	    (pcie_ports_native || host->native_pme)) {
+	if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT && host->native_pme) {
 		services |= PCIE_PORT_SERVICE_PME;
 
 		/*