Re: [PATCH 2/4] fpga: dfl: Move DFH header register macros to linux/dfl.h

[Xu Yilun <yilun.xu@xxxxxxxxx>]

On Tue, Jun 22, 2021 at 05:31:57AM -0700, Tom Rix wrote:
> 
> On 6/21/21 9:56 PM, Xu Yilun wrote:
> > On Mon, Jun 21, 2021 at 06:56:28AM -0700, Tom Rix wrote:
> > > On 6/21/21 12:06 AM, Martin Hundebøll wrote:
> > > > From: Debarati Biswas <debaratix.biswas@xxxxxxxxx>
> > > > 
> > > > Device Feature List (DFL) drivers may be defined in subdirectories other
> > > > than drivers/fpga, and each DFL driver should have access to the Device
> > > > Feature Header (DFH) register, which contains revision and type
> > > > information. This change moves the macros specific to the DFH register
> > > > from drivers/fpga/dfl.h to include/linux/dfl.h.
> > > > 
> > > > Signed-off-by: Debarati Biswas <debaratix.biswas@xxxxxxxxx>
> > > > Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> > > > Signed-off-by: Martin Hundebøll <mhu@xxxxxxxxxx>
> > > > ---
> > > >    drivers/fpga/dfl.h  | 48 +----------------------------------------
> > > >    include/linux/dfl.h | 52 +++++++++++++++++++++++++++++++++++++++++++++
> > > >    2 files changed, 53 insertions(+), 47 deletions(-)
> > > > 
> > > > diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
> > > > index 2b82c96ba56c..6ed0353e9a99 100644
> > > > --- a/drivers/fpga/dfl.h
> > > > +++ b/drivers/fpga/dfl.h
> > > > @@ -17,6 +17,7 @@
> > > >    #include <linux/bitfield.h>
> > > bitfield.h was added to linux/dfl.h
> > > 
> > > Likely both aren't needed, try removing this one.
> > The DFL register definitions are in dfl.h, and Source files which include
> > dfl.h are likely to use bitfield ops for DFL register access, so could we
> > keep it here?
> 
> Not sure which dfl.h you mean.
> 
> It looks like you are copying header includes in both files and including
> the one file in the other.
> 
> So it is likely you are including headers you don't need.

Maybe I misunderstand, I thought you suggest remove the headers in both
drivers/fpga/dfl.h and linux/dfl.h.

Move the bitfield.h from drivers/fpga/dfl.h to linux/dfl.h is good to
me.

Thanks,
Yilun

> 
> Tom
> 
> > 
> > Thanks,
> > Yilun
> > 
> > > Tom
> > > 
> > > >    #include <linux/cdev.h>
> > > >    #include <linux/delay.h>
> > > > +#include <linux/dfl.h>
> > > >    #include <linux/eventfd.h>
> > > >    #include <linux/fs.h>
> > > >    #include <linux/interrupt.h>
> > > > @@ -53,32 +54,6 @@
> > > >    #define PORT_FEATURE_ID_UINT		0x12
> > > >    #define PORT_FEATURE_ID_STP		0x13
> > > > -/*
> > > > - * Device Feature Header Register Set
> > > > - *
> > > > - * For FIUs, they all have DFH + GUID + NEXT_AFU as common header registers.
> > > > - * For AFUs, they have DFH + GUID as common header registers.
> > > > - * For private features, they only have DFH register as common header.
> > > > - */
> > > > -#define DFH			0x0
> > > > -#define GUID_L			0x8
> > > > -#define GUID_H			0x10
> > > > -#define NEXT_AFU		0x18
> > > > -
> > > > -#define DFH_SIZE		0x8
> > > > -
> > > > -/* Device Feature Header Register Bitfield */
> > > > -#define DFH_ID			GENMASK_ULL(11, 0)	/* Feature ID */
> > > > -#define DFH_ID_FIU_FME		0
> > > > -#define DFH_ID_FIU_PORT		1
> > > > -#define DFH_REVISION		GENMASK_ULL(15, 12)	/* Feature revision */
> > > > -#define DFH_NEXT_HDR_OFST	GENMASK_ULL(39, 16)	/* Offset to next DFH */
> > > > -#define DFH_EOL			BIT_ULL(40)		/* End of list */
> > > > -#define DFH_TYPE		GENMASK_ULL(63, 60)	/* Feature type */
> > > > -#define DFH_TYPE_AFU		1
> > > > -#define DFH_TYPE_PRIVATE	3
> > > > -#define DFH_TYPE_FIU		4
> > > > -
> > > >    /* Next AFU Register Bitfield */
> > > >    #define NEXT_AFU_NEXT_DFH_OFST	GENMASK_ULL(23, 0)	/* Offset to next AFU */
> > > > @@ -403,27 +378,6 @@ struct device *dfl_fpga_pdata_to_parent(struct dfl_feature_platform_data *pdata)
> > > >    	return pdata->dev->dev.parent->parent;
> > > >    }
> > > > -static inline bool dfl_feature_is_fme(void __iomem *base)
> > > > -{
> > > > -	u64 v = readq(base + DFH);
> > > > -
> > > > -	return (FIELD_GET(DFH_TYPE, v) == DFH_TYPE_FIU) &&
> > > > -		(FIELD_GET(DFH_ID, v) == DFH_ID_FIU_FME);
> > > > -}
> > > > -
> > > > -static inline bool dfl_feature_is_port(void __iomem *base)
> > > > -{
> > > > -	u64 v = readq(base + DFH);
> > > > -
> > > > -	return (FIELD_GET(DFH_TYPE, v) == DFH_TYPE_FIU) &&
> > > > -		(FIELD_GET(DFH_ID, v) == DFH_ID_FIU_PORT);
> > > > -}
> > > > -
> > > > -static inline u8 dfl_feature_revision(void __iomem *base)
> > > > -{
> > > > -	return (u8)FIELD_GET(DFH_REVISION, readq(base + DFH));
> > > > -}
> > > > -
> > > >    /**
> > > >     * struct dfl_fpga_enum_info - DFL FPGA enumeration information
> > > >     *
> > > > diff --git a/include/linux/dfl.h b/include/linux/dfl.h
> > > > index 6cc10982351a..1cd86b2e7cb1 100644
> > > > --- a/include/linux/dfl.h
> > > > +++ b/include/linux/dfl.h
> > > > @@ -8,7 +8,9 @@
> > > >    #ifndef __LINUX_DFL_H
> > > >    #define __LINUX_DFL_H
> > > > +#include <linux/bitfield.h>
> > > >    #include <linux/device.h>
> > > > +#include <linux/io.h>
> > > >    #include <linux/mod_devicetable.h>
> > > >    /**
> > > > @@ -83,4 +85,54 @@ void dfl_driver_unregister(struct dfl_driver *dfl_drv);
> > > >    	module_driver(__dfl_driver, dfl_driver_register, \
> > > >    		      dfl_driver_unregister)
> > > > +/*
> > > > + * Device Feature Header Register Set
> > > > + *
> > > > + * For FIUs, they all have DFH + GUID + NEXT_AFU as common header registers.
> > > > + * For AFUs, they have DFH + GUID as common header registers.
> > > > + * For private features, they only have DFH register as common header.
> > > > + */
> > > > +#define DFH                     0x0
> > > > +#define GUID_L                  0x8
> > > > +#define GUID_H                  0x10
> > > > +#define NEXT_AFU                0x18
> > > > +
> > > > +#define DFH_SIZE                0x8
> > > > +
> > > > +/* Device Feature Header Register Bitfield */
> > > > +#define DFH_ID                  GENMASK_ULL(11, 0)      /* Feature ID */
> > > > +#define DFH_ID_FIU_FME          0
> > > > +#define DFH_ID_FIU_PORT         1
> > > > +#define DFH_REVISION            GENMASK_ULL(15, 12)
> > > > +#define DFH_NEXT_HDR_OFST       GENMASK_ULL(39, 16)     /* Offset to next DFH */
> > > > +#define DFH_EOL                 BIT_ULL(40)             /* End of list */
> > > > +#define DFH_TYPE                GENMASK_ULL(63, 60)     /* Feature type */
> > > > +#define DFH_TYPE_AFU            1
> > > > +#define DFH_TYPE_PRIVATE        3
> > > > +#define DFH_TYPE_FIU            4
> > > > +
> > > > +/* Function to read from DFH and check if the Feature type is FME */
> > > > +static inline bool dfl_feature_is_fme(void __iomem *base)
> > > > +{
> > > > +	u64 v = readq(base + DFH);
> > > > +
> > > > +	return (FIELD_GET(DFH_TYPE, v) == DFH_TYPE_FIU) &&
> > > > +		(FIELD_GET(DFH_ID, v) == DFH_ID_FIU_FME);
> > > > +}
> > > > +
> > > > +/* Function to read from DFH and check if the Feature type is port*/
> > > > +static inline bool dfl_feature_is_port(void __iomem *base)
> > > > +{
> > > > +	u64 v = readq(base + DFH);
> > > > +
> > > > +	return (FIELD_GET(DFH_TYPE, v) == DFH_TYPE_FIU) &&
> > > > +		 (FIELD_GET(DFH_ID, v) == DFH_ID_FIU_PORT);
> > > > +}
> > > > +
> > > > +/* Function to read feature revision from DFH */
> > > > +static inline u8 dfl_feature_revision(void __iomem *base)
> > > > +{
> > > > +	return (u8)FIELD_GET(DFH_REVISION, readq(base + DFH));
> > > > +}
> > > > +
> > > >    #endif /* __LINUX_DFL_H */