On Sun, 2007-07-15 at 09:04 -0400, Dan Williams wrote:
> On Sat, 2007-07-14 at 16:38 -0400, Mike Frysinger wrote:
> > On 7/14/07, Michael Buesch <[EMAIL PROTECTED]> wrote:
> > > On Saturday 14 July 2007 21:49:21 Mike Frysinger wrote:
> > > > On 7/14/07, Michael Buesch <[EMAIL PROTECTED]> wrote:
> > > > > On Saturday 14 July 2007 20:49:53 Bryan Wu wrote:
> > > > > > +static int __init bf537mac_probe(struct net_device *dev)
> > > > > > +{
> > > > > > + struct bf537mac_local *lp = netdev_priv(dev);
> > > > > > + int retval;
> > > > > > +
> > > > > > + /* Grab the MAC address in the MAC */
> > > > > > + *(u32 *) (&(dev->dev_addr[0])) = bfin_read_EMAC_ADDRLO();
> > > > > > + *(u16 *) (&(dev->dev_addr[4])) = (u16)
> > > > > > bfin_read_EMAC_ADDRHI();
> > > > >
> > > > > Endianess broken.
> > > > >
> > > > > > +struct dma_config_reg {
> > > > > > + unsigned short b_DMA_EN:1; /* Bit 0 : DMA Enable */
> > > > > > + unsigned short b_WNR:1; /* Bit 1 : DMA Direction */
> > > > > > + unsigned short b_WDSIZE:2; /* Bit 2 & 3 : DMA Tranfer Word
> > > > > > size */
> > > > > > + unsigned short b_DMA2D:1; /* Bit 4 : DMA Mode 2D or 1D */
> > > > > > + unsigned short b_RESTART:1; /* Bit 5 : Retain the FIFO */
> > > > > > + unsigned short b_DI_SEL:1; /* Bit 6 : Data Interrupt Timing
> > > > > > Select */
> > > > > > + unsigned short b_DI_EN:1; /* Bit 7 : Data Interrupt Enable
> > > > > > */
> > > > > > + unsigned short b_NDSIZE:4; /* Bit 8 to 11 : Flex descriptor
> > > > > > Size */
> > > > > > + unsigned short b_FLOW:3; /* Bit 12 to 14 : FLOW */
> > > > > > +};
> > > > >
> > > > > This is most likely not endianess safe.
> > > >
> > > > do we really need to care about this ? this is a driver for a MAC
> > > > which can only be found on Blackfin processors and Blackfin itself is
> > > > only little endian.
> > >
> > > Well, this bitfield _might_ be OK (although I don't like bitfields
> > > at all), but the above pointer casting stuff should really use
> > > leXX_to_cpu. It's so easy to use and it is easier to read and
> > > maintain the code afterwards.
> >
> > i think that's arguable ... i dont see how:
> > a = foo(b);
> > is easier to read than:
> > a = b;
> > but it is easy to use ... i guess my point was more along the lines of
> > wasting further time auditing a driver for endianness issues that will
> > never actually be an issue.
>
> Sometimes by doing this you catch bugs you didn't see before. It's a
> good thing to do generally. Does sparse with endianness check show
> errors? You may want to fix those.
>
> Dan
Yes, I will add endianess protection as Michael and you mentioned.
Thanks
- Bryan Wu
> > -mike
> > -
> > To unsubscribe from this list: send the line "unsubscribe netdev" in
> > the body of a message to [EMAIL PROTECTED]
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
