Re: [parisc-linux] byte swapping redux

["Joel Soete" <jsoe0708@tiscali.be>]

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> Maybe our userspace will encounter this problem as well since I've
> ripped out the __STRICT_ANSI__ test...can you work this out?

I will see what I can do for this 

> > I also write this small testcase to try to point out the pb in 32bits
mode:
> ...
> > And here is the results:
> > Val of TU64: fedcba9876543210
> > Val of ___arch__swab64(TU64): 76543210fedcba98
> > Val of __fswab64(TU64): 1032547698badcfe
[...]
> __fswab64() is correct.
> ___arch__swab64() didn't actually swap within the  32-bit word
[...]

static __inline__ __const__ __u64 ___arch__swab64(__u64 x)
{
	__u32 t1 = (__u32) x;
	__u32 t2 = (__u32) ((x) >> 32);
	return ((__u64) ___arch__swab32(t1) << 32) + ((__u64) ___arch__swab32(t2))
>     
}

That works for my 32bits kernel on my b2k :-) (just replace 't1' by 'l' and
't2' by 'h' ;) )

btw here is also a small patch I just test also for cdrom pb encounter by
somebody else:
--- system_irqsave.h.orig	2003-07-02 17:34:02.000000000 +0200
+++ system_irqsave.h	2003-07-02 17:35:59.000000000 +0200
@@ -7,8 +7,13 @@
 #define __cli()	__asm__ __volatile__("rsm %0,%%r0\n" : : "i" (PSW_I) : "memory"
)
 #define __sti()	__asm__ __volatile__("ssm %0,%%r0\n" : : "i" (PSW_I) : "memory"
)
 
+#define __save_and_cli(x)  do { __save_flags(x); __cli(); } while(0);
+#define __save_and_sti(x)  do { __save_flags(x); __sti(); } while(0);
+
+/* For spinlocks etc */
 #define local_irq_save(x) \
 	__asm__ __volatile__("rsm %1,%0" : "=r" (x) :"i" (PSW_I) : "memory" )
+#define local_irq_set(x)   __save_and_sti(x)
 #define local_irq_restore(x) \
 	__asm__ __volatile__("mtsm %0" : : "r" (x) : "memory" )
 #define local_irq_disable() __cli()

( may be possible to do better ??)

Joel





---------------------------------
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--- system_irqsave.h.orig	2003-07-02 17:34:02.000000000 +0200
+++ system_irqsave.h	2003-07-02 17:35:59.000000000 +0200
@@ -7,8 +7,13 @@
 #define __cli()	__asm__ __volatile__("rsm %0,%%r0\n" : : "i" (PSW_I) : "memory" )
 #define __sti()	__asm__ __volatile__("ssm %0,%%r0\n" : : "i" (PSW_I) : "memory" )
 
+#define __save_and_cli(x)  do { __save_flags(x); __cli(); } while(0);
+#define __save_and_sti(x)  do { __save_flags(x); __sti(); } while(0);
+
+/* For spinlocks etc */
 #define local_irq_save(x) \
 	__asm__ __volatile__("rsm %1,%0" : "=r" (x) :"i" (PSW_I) : "memory" )
+#define local_irq_set(x)   __save_and_sti(x)
 #define local_irq_restore(x) \
 	__asm__ __volatile__("mtsm %0" : : "r" (x) : "memory" )
 #define local_irq_disable() __cli()