| Message ID | 20240509121713.190076-2-thorsten.blum@toblux.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: smc91x: Fix m68k kernel compilation for ColdFire CPU | expand |
On Thu, May 09, 2024 at 02:17:14PM +0200, Thorsten Blum wrote: > Compiling the m68k kernel with support for the ColdFire CPU family fails > with the following error: > > In file included from drivers/net/ethernet/smsc/smc91x.c:80: > drivers/net/ethernet/smsc/smc91x.c: In function ‘smc_reset’: > drivers/net/ethernet/smsc/smc91x.h:160:40: error: implicit declaration of function ‘_swapw’; did you mean ‘swap’? [-Werror=implicit-function-declaration] > 160 | #define SMC_outw(lp, v, a, r) writew(_swapw(v), (a) + (r)) > | ^~~~~~ > drivers/net/ethernet/smsc/smc91x.h:904:25: note: in expansion of macro ‘SMC_outw’ > 904 | SMC_outw(lp, x, ioaddr, BANK_SELECT); \ > | ^~~~~~~~ > drivers/net/ethernet/smsc/smc91x.c:250:9: note: in expansion of macro ‘SMC_SELECT_BANK’ > 250 | SMC_SELECT_BANK(lp, 2); > | ^~~~~~~~~~~~~~~ > cc1: some warnings being treated as errors > > The function _swapw() was removed in commit d97cf70af097 ("m68k: use > asm-generic/io.h for non-MMU io access functions"), but is still used in > drivers/net/ethernet/smsc/smc91x.h. > > Re-adding the previously deleted _swapw() function resolves the error. This seems like the wrong fix. commit d97cf70af09721ef416c61faa44543e3b84c9a55 Author: Greg Ungerer <gerg@linux-m68k.org> Date: Fri Mar 23 23:39:10 2018 +1000 m68k: use asm-generic/io.h for non-MMU io access functions There is nothing really special about the non-MMU m68k IO access functions. So we can easily switch to using the asm-generic/io.h functions. So it rather than put something back which there is an aim to remove, please find the generic replacement. This _swapw() swaps a 16 bit word. The generic for that is swab16(). I'm also surprised it took 6 years to find this. Has something else changed recently? Andrew --- pw-bot: cr
On Thu, May 9, 2024, at 14:17, Thorsten Blum wrote: > > +static inline unsigned short _swapw(volatile unsigned short v) > +{ > + return ((v << 8) | (v >> 8)); > +} > + > #define SMC_inw(a, r) _swapw(readw((a) + (r))) > #define SMC_outw(lp, v, a, r) writew(_swapw(v), (a) + (r)) > #define SMC_insw(a, r, p, l) mcf_insw(a + r, p, l) I think you can just use iowrite16_be() and ioread16_be() here in place of the little-endian access plus swap. Also, it looks like it's been broken for six years without anyone noticing the problem, so I wonder if there are even still any machines that use this driver and get kernel updates. Arnd
On 9. May 2024, at 22:36, Andrew Lunn <andrew@lunn.ch> wrote: > This seems like the wrong fix. > > commit d97cf70af09721ef416c61faa44543e3b84c9a55 > Author: Greg Ungerer <gerg@linux-m68k.org> > Date: Fri Mar 23 23:39:10 2018 +1000 > > m68k: use asm-generic/io.h for non-MMU io access functions > > There is nothing really special about the non-MMU m68k IO access functions. > So we can easily switch to using the asm-generic/io.h functions. > > So it rather than put something back which there is an aim to remove, > please find the generic replacement. This _swapw() swaps a 16 bit > word. The generic for that is swab16(). Thanks. I will use ioread16be() and iowrite16be() as suggested by Arnd instead and submit a v2 shortly. Thorsten
diff --git a/drivers/net/ethernet/smsc/smc91x.h b/drivers/net/ethernet/smsc/smc91x.h index 46eee747c699..e5d7f49915c6 100644 --- a/drivers/net/ethernet/smsc/smc91x.h +++ b/drivers/net/ethernet/smsc/smc91x.h @@ -156,6 +156,11 @@ static inline void mcf_outsw(void *a, unsigned char *p, int l) writew(*wp++, a); } +static inline unsigned short _swapw(volatile unsigned short v) +{ + return ((v << 8) | (v >> 8)); +} + #define SMC_inw(a, r) _swapw(readw((a) + (r))) #define SMC_outw(lp, v, a, r) writew(_swapw(v), (a) + (r)) #define SMC_insw(a, r, p, l) mcf_insw(a + r, p, l)
Compiling the m68k kernel with support for the ColdFire CPU family fails with the following error: In file included from drivers/net/ethernet/smsc/smc91x.c:80: drivers/net/ethernet/smsc/smc91x.c: In function ‘smc_reset’: drivers/net/ethernet/smsc/smc91x.h:160:40: error: implicit declaration of function ‘_swapw’; did you mean ‘swap’? [-Werror=implicit-function-declaration] 160 | #define SMC_outw(lp, v, a, r) writew(_swapw(v), (a) + (r)) | ^~~~~~ drivers/net/ethernet/smsc/smc91x.h:904:25: note: in expansion of macro ‘SMC_outw’ 904 | SMC_outw(lp, x, ioaddr, BANK_SELECT); \ | ^~~~~~~~ drivers/net/ethernet/smsc/smc91x.c:250:9: note: in expansion of macro ‘SMC_SELECT_BANK’ 250 | SMC_SELECT_BANK(lp, 2); | ^~~~~~~~~~~~~~~ cc1: some warnings being treated as errors The function _swapw() was removed in commit d97cf70af097 ("m68k: use asm-generic/io.h for non-MMU io access functions"), but is still used in drivers/net/ethernet/smsc/smc91x.h. Re-adding the previously deleted _swapw() function resolves the error. Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com> --- drivers/net/ethernet/smsc/smc91x.h | 5 +++++ 1 file changed, 5 insertions(+)