RE: [PATCH V2 1/3] NTB: Add AMD PCI-Express NTB driver

From: Yu, Xiangliang
Date: Wed Jan 06 2016 - 21:50:55 EST


> > +
> > +#define PCI_DEVICE_ID_AMD_NTB 0x145B
>
> This looks like a tab and not a space

I'll update it.

>
> > +#define AMD_LINK_HB_TIMEOUT msecs_to_jiffies(1000)
> > +#define AMD_LINK_STATUS_OFFSET 0x68
> > +#define NTB_LIN_STA_ACTIVE_BIT 0x00000002
> > +#define NTB_LNK_STA_SPEED_MASK 0x000F0000
> > +#define NTB_LNK_STA_WIDTH_MASK 0x03F00000
> > +#define NTB_LNK_STA_ACTIVE(x) (!!((x) & NTB_LIN_STA_ACTIVE_BIT))
> > +#define NTB_LNK_STA_SPEED(x) (((x) & NTB_LNK_STA_SPEED_MASK) >>
> 16)
> > +#define NTB_LNK_STA_WIDTH(x) (((x) &
> NTB_LNK_STA_WIDTH_MASK) >> 20)
> > +
> > +#ifndef ioread64
> > +#ifdef readq
> > +#define ioread64 readq
> > +#else
> > +#define ioread64 _ioread64
> > +static inline u64 _ioread64(void __iomem *mmio)
> > +{
> > + u64 low, high;
> > +
> > + low = ioread32(mmio);
> > + high = ioread32(mmio + sizeof(u32));
> > + return low | (high << 32);
> > +}
> > +#endif
> > +#endif
> > +
> > +#ifndef iowrite64
> > +#ifdef writeq
> > +#define iowrite64 writeq
> > +#else
> > +#define iowrite64 _iowrite64
> > +static inline void _iowrite64(u64 val, void __iomem *mmio)
> > +{
> > + iowrite32(val, mmio);
> > + iowrite32(val >> 32, mmio + sizeof(u32));
> > +}
> > +#endif
> > +#endif
> >

How about put ioread64/iowrite64 macro into ntb.h file? So low level driver can avoid to define these macro.

> > +#define NTB_READ_REG(base, r) (ioread32(base + AMD_ ## r ##
> _OFFSET))
> > +#define NTB_WRITE_REG(base, val, r) (iowrite32(val, base + \
> > + AMD_ ## r ## _OFFSET))
> > +#define NTB_READ_OFFSET(base, r, of) (ioread32(base + of + \
> > + AMD_ ## r ## _OFFSET))
> > +#define NTB_WRITE_OFFSET(base, val, r, of) (iowrite32(val, base + \
> > + of + AMD_ ## r ## _OFFSET))
>
> Please do not use marcos to hide ioread/iowrite. Call iorwad/iowrite directly.

I don't see any wrong to hide ioread/iowrite, and I think the macros can make code readable and easy to maintain.