On Monday 10 August 2009 20:49:02 Gábor Stefanik wrote:
> Also add a "SPEX32" macro for extracting 32-bit SPROM variables.
>
> Signed-off-by: Gábor Stefanik <netrolller.3d@xxxxxxxxx>
> ---
> I'm not quite sure that the SPEX32 macro is sane endianness-wise;
> please review it carefully. (In the future, we will probably need
> a SPEX64 macro too, to correctly extract boardflags.)
>
> drivers/ssb/pci.c | 53 +++++++++++++++++++++++++++++++++-
> include/linux/ssb/ssb.h | 44 +++++++++++++++++++++++----
> include/linux/ssb/ssb_regs.h | 66 +++++++++++++++++++++++++++++++++++++----
> 3 files changed, 148 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/ssb/pci.c b/drivers/ssb/pci.c
> index 40ea417..50811e4 100644
> --- a/drivers/ssb/pci.c
> +++ b/drivers/ssb/pci.c
> @@ -169,8 +169,14 @@ err_pci:
> /* Get the word-offset for a SSB_SPROM_XXX define. */
> #define SPOFF(offset) (((offset) - SSB_SPROM_BASE) / sizeof(u16))
> /* Helper to extract some _offset, which is one of the SSB_SPROM_XXX defines. */
> -#define SPEX(_outvar, _offset, _mask, _shift) \
> +#define SPEX16(_outvar, _offset, _mask, _shift) \
> out->_outvar = ((in[SPOFF(_offset)] & (_mask)) >> (_shift))
> +#define SPEX32(_outvar, _offset, _mask, _shift) \
> + out->_outvar = ((((in[SPOFF((_offset)+2)] << sizeof(u16)) | \
^^^^^^^^^^^^^^
This shifts by 2 bit. Did you want 16 bits? Just write << 16 then.
Also, it seems you need +1 instead of +2 (it is an u16 pointer).
I also usually cast u16 values to u32 before shifting >=16 bits.
The result of shifting a 16bit variable left by 16bits is machine dependent.
It works as expected for every linux architecture, but I prefer the cast anyway.
Your macro extracts the value in littleendian format. I didn't check if this is
correct for your values. But there also are values stored in BE format.
--
Greetings, Michael.
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
