Hi Detlev On 09/09/11 13:09, Detlev Zundel wrote: > Hi, > >> Dear Dave Aldridge, >> >> In message <[email protected]> you wrote: >>> If CONFIG_SYS_NS16550_MEM32 is defined then 32 bit memory >>> mapped access will be used to read/write the uart registers. >>> >>> This is especially useful for SoC devices that implement 16550 >>> compatible uarts but that have peripheral access width constraints. >>> >>> Signed-off-by: Dave Aldridge <[email protected]> >> ... >> >>> --- a/drivers/serial/ns16550.c >>> +++ b/drivers/serial/ns16550.c >>> @@ -19,6 +19,12 @@ >>> #ifdef CONFIG_SYS_NS16550_PORT_MAPPED >>> #define serial_out(x,y) outb(x,(ulong)y) >>> #define serial_in(y) inb((ulong)y) >>> +#elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE > >>> 0) >>> +#define serial_out(x,y) out_be32(y,x) >>> +#define serial_in(y) in_be32(y) >>> +#elif defined(CONFIG_SYS_NS16550_MEM32) && (CONFIG_SYS_NS16550_REG_SIZE < >>> 0) >>> +#define serial_out(x,y) out_le32(y,x) >>> +#define serial_in(y) in_le32(y) >> >> Sorry for the dumb question, but in which way is REG_SIZE > 0 or >> REG_SIZE < 0 connected to the endianess of the target system? >> >> My understanding is that this only defines how byte wide registers >> need to be padded, i. e. wether they are connected to the highest or >> to the lowest byte lane. THis has nothing to do with the endianess of >> the system, and it appears wrong to me, to imply such a relation here. >> >> Detlev, what do you think? > > I _think_ that if we are concerned with the question of where a one-byte > entity is placed in relation to its embracing 32-bit unit, then this is > the definiton of endianness, right? Actually the endianness of the > UART, and this is exactly what the interpretation of the sign of the > REG_SIZE macro is. > > So if the patch works for Dave, he gets my > > Acked-by: Detlev Zundel <[email protected]> > > on the latter version. >
Just to confirm that the V4 patch does work for me. > Cheers > Detlev > _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
