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reformat

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This commit is contained in:
Markus Fröschle
2015-10-13 05:14:06 +00:00
parent 35d879b698
commit d118796306
1 changed files with 19 additions and 14 deletions
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33
if/driver_vec.c
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@@ -236,36 +236,41 @@ void remove_handler(void)
*trap_0_vector = (uint32_t) std_exc_vec;
}
/*
* trap #0 entry point
*
* this is used to retrieve the driver table that gets exposed to the OS by BaS
*/
void __attribute__((interrupt)) get_bas_drivers(void)
{
__asm__ __volatile(
/*
* sp should now point to the next instruction after the trap
* The trap itself is 2 bytes, the four bytes before that must
* read '_BAS' or we are not meant by this call
* read '_BAS', otherwise we are not meant by this call
*/
" move.l a0,-(sp) \n\t" // save registers
" move.l a0,-(sp) \n\t" // save registers
" move.l d0,-(sp) \n\t"
" move.l 12(sp),a0 \n\t" // get return address
" move.l 12(sp),a0 \n\t" // get return address
" move.l -6(a0),d0 \n\t" //
" cmp.l #0x5f424153,d0 \n\t" // is it '_BAS'?
" beq fetch_drivers \n\t" // yes
" cmp.l #0x5f424153,d0 \n\t" // is it '_BAS'?
" beq fetch_drivers \n\t" // yes
/*
* This seems indeed a "normal" trap #0. Better pass control to "normal" trap #0 processing
* If trap #0 isn't set to something sensible, we'll probably crash here, but this must be
* prevented on the caller side.
*/
" move.l (sp)+,d0 \n\t" // restore registers
" move.l (sp)+,a0 \n\t"
" move.l 0x80,-(sp) \n\t" // fetch vector
" rts \n\t" // and jump through it
" move.l (sp)+,d0 \n\t" // restore registers
" move.l (sp)+,a0 \n\t"
" move.l 0x80,-(sp) \n\t" // fetch vector
" rts \n\t" // and jump through it
"fetch_drivers: \n\t"
" move.l #%[drivers],d0 \n\t" // return driver struct in d0
" addq.l #4,sp \n\t" // adjust stack
"fetch_drivers: \n\t"
" move.l #%[drivers],d0 \n\t" // return driver struct in d0
" addq.l #4,sp \n\t" // adjust stack
" move.l (sp)+,a0 \n\t" // restore register
: /* no output */
: [drivers] "o" (bas_drivers) /* input */
: /* clobber */
: [drivers] "o" (bas_drivers) /* input */
: /* clobber */
);
}