On Tue, Mar 31, 2020 at 10:07:07AM -0700, Dave Jiang wrote:
>
> On 3/31/2020 3:04 AM, Greg KH wrote:
> > On Mon, Mar 30, 2020 at 02:27:00PM -0700, Dave Jiang wrote:
> > > Since the current accelerator devices do not have standard PCIe capability
> > > enumeration for accepting ENQCMDS yet, for now an attribute of pdev->cmdmem has
> > > been added to struct pci_dev. Currently a PCI quirk must be used for the
> > > devices that have such cap until the PCI cap is standardized. Add a helper
> > > function to provide the check if a device supports the cmdmem capability.
> > >
> > > Such capability is expected to be added to PCIe device cap enumeration in
> > > the future.
> > >
> > > Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> > > ---
> > > drivers/base/core.c | 13 +++++++++++++
> > > include/linux/device.h | 2 ++
> > > include/linux/pci.h | 1 +
> > > 3 files changed, 16 insertions(+)
> > >
> > > diff --git a/drivers/base/core.c b/drivers/base/core.c
> > > index dbb0f9130f42..cd9f5b040ed4 100644
> > > --- a/drivers/base/core.c
> > > +++ b/drivers/base/core.c
> > > @@ -27,6 +27,7 @@
> > > #include <linux/netdevice.h>
> > > #include <linux/sched/signal.h>
> > > #include <linux/sysfs.h>
> > > +#include <linux/pci.h>
> > > #include "base.h"
> > > #include "power/power.h"
> > > @@ -3790,3 +3791,15 @@ int device_match_any(struct device *dev, const void *unused)
> > > return 1;
> > > }
> > > EXPORT_SYMBOL_GPL(device_match_any);
> > > +
> > > +bool device_supports_cmdmem(struct device *dev)
> > > +{
> > > + struct pci_dev *pdev;
> > > +
> > > + if (!dev_is_pci(dev))
> > > + return false;
> > > +
> > > + pdev = to_pci_dev(dev);
> > > + return pdev->cmdmem;
> > > +}
> > > +EXPORT_SYMBOL_GPL(device_supports_cmdmem);
> > Why would a pci-specific function like this be ok to have in the driver
> > core? Please keep it in the pci core code instead.
>
> The original thought was to introduce a new arch level memory mapping
> semantic.
Please do not. Also, that's not what you are doing here from what I can
tell.
> If you feel this should be PCI exclusive, should we make the ioremap
> routines for this memory type pci specific as well?
Why wouldn't it be? Is this needed anywhere else?
thanks,
greg k-h
