Thanks Bjorn & Martin! -Sean > -----Original Message----- > From: Bjorn Helgaas [mailto:helgaas@xxxxxxxxxx] > Sent: Monday, May 16, 2016 1:32 PM > To: Stalley, Sean <sean.stalley@xxxxxxxxx> > Cc: linux-pci@xxxxxxxxxxxxxxx; mj@xxxxxx; bhelgaas@xxxxxxxxxx; > alex.williamson@xxxxxxxxxx; david.daney@xxxxxxxxxx > Subject: Re: [PATCH v4 1/2] pci: Identify Enhanced Allocation (EA) BAR > Equivalent resources > > On Thu, Feb 11, 2016 at 04:52:24PM -0800, Sean O. Stalley wrote: > > From: Alex Williamson <alex.williamson@xxxxxxxxxx> > > > > Resource flags are exposed to userspace via the sysfs "resource" file. > > lspci reads the sysfs file to determine resource properties. > > Adding this flag allows lspci to distinguish between [virtual] and > > [enhanced] resources. > > > > If the resource is not aligned, userspace could deduce where the > > resource is EA based on the size & address fields. > > However, a flag indicating whether a PCI resource is a traditional BAR > > or BAR equivalent seems like a much simpler solution and works if the > > EA resource is aligned. > > > > Although this patchset only improves lspci, other uses for this flag > > have been identified. For example, vfio makes assumptions about > > alignment and sizing, and runs into problems when attempting to > > emulate a BAR Equivalent EA resource. > > > > Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> > > Signed-off-by: Sean O. Stalley <sean.stalley@xxxxxxxxx> > > I applied this to pci/resource and intend to merge it for v4.7. > > > --- > > drivers/pci/pci.c | 2 +- > > include/linux/ioport.h | 7 +++++++ > > 2 files changed, 8 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index > > d1a7105..8ff678c 100644 > > --- a/drivers/pci/pci.c > > +++ b/drivers/pci/pci.c > > @@ -2229,7 +2229,7 @@ void pci_pm_init(struct pci_dev *dev) > > > > static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop) { > > - unsigned long flags = IORESOURCE_PCI_FIXED; > > + unsigned long flags = IORESOURCE_PCI_FIXED | > IORESOURCE_PCI_EA_BEI; > > > > switch (prop) { > > case PCI_EA_P_MEM: > > diff --git a/include/linux/ioport.h b/include/linux/ioport.h index > > 24bea08..88816f9 100644 > > --- a/include/linux/ioport.h > > +++ b/include/linux/ioport.h > > @@ -25,7 +25,11 @@ struct resource { > > > > /* > > * IO resources have these defined flags. > > + * > > + * PCI devices expose these flags to userspace in the "resource" > > + sysfs file, > > + * Moving them around could break stuff, so don't do it. > > */ > > + > > #define IORESOURCE_BITS 0x000000ff /* Bus-specific bits */ > > > > #define IORESOURCE_TYPE_BITS 0x00001f00 /* Resource type */ > > @@ -97,6 +101,7 @@ struct resource { > > #define IORESOURCE_IO_SPARSE (1<<2) > > > > /* PCI ROM control bits (IORESOURCE_BITS) */ > > + > > #define IORESOURCE_ROM_ENABLE (1<<0) /* ROM is enabled, > same as PCI_ROM_ADDRESS_ENABLE */ > > #define IORESOURCE_ROM_SHADOW (1<<1) /* ROM is copy at > C000:0 */ > > #define IORESOURCE_ROM_COPY (1<<2) /* ROM is alloc'd copy, > resource field overlaid */ > > @@ -105,6 +110,8 @@ struct resource { > > /* PCI control bits. Shares IORESOURCE_BITS with above PCI ROM. */ > > #define IORESOURCE_PCI_FIXED (1<<4) /* Do not move > resource */ > > > > +/* PCI Enhanced Allocation defined BAR equivalent resource */ > > +#define IORESOURCE_PCI_EA_BEI (1<<5) > > > > /* helpers to define resources */ > > #define DEFINE_RES_NAMED(_start, _size, _name, _flags) > \ > > -- > > 1.9.1 > > > > -- > > 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 -- 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
