patches/glibc/2.9/530-powerpc-8xx-CPU15-errata.patch
author "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Tue Jun 08 23:26:54 2010 +0200 (2010-06-08)
changeset 1976 2d90ec981ba3
parent 1016 a059741f7bd4
permissions -rw-r--r--
config: add support for a second part of the generated choices

Some components have configuration options that can depend on
generic options, so they should go below those.

uClibc for example:
- has its own options (wchar...)
- uses the generic options (threads...)
- if linuxthreads chosen, offers two impls

So we need to be able to split the components options in 2,
one part that is above the generic options, and one part that
ends up below the generic options.
     1 Fix memset on PowerPC 8xx, by Nye Liu:
     2 http://sourceware.org/ml/crossgcc/2008-10/msg00067.html
     3 
     4 Quote:
     5  I am working on a powerpc 860 toolchain, but I am having problems  
     6  convincing glibc to not emit code that uses the dcbz instruction (CPU15  
     7  dcbX bug). The source of the problem is sysdeps/powerpc/power3/memset.S
     8 
     9 --- glibc-2.7/sysdeps/powerpc/powerpc32/memset.S	2007-03-26 13:09:07.000000000 -0700
    10 +++ glibc-2.7/sysdeps/powerpc/powerpc32/memset.S.new	2008-10-23 20:28:52.000000000 -0700
    11 @@ -112,11 +112,13 @@
    12  	clrrwi.	rALIGN, rLEN, 5
    13  	mtcrf	0x01, rLEN	/* 40th instruction from .align */
    14  
    15 +#ifndef BROKEN_PPC_8xx_CPU15
    16  /* Check if we can use the special case for clearing memory using dcbz.
    17     This requires that we know the correct cache line size for this
    18     processor.  Getting the __cache_line_size may require establishing GOT
    19     addressability, so branch out of line to set this up.  */
    20  	beq	cr1, L(checklinesize)
    21 +#endif
    22  
    23  /* Store blocks of 32-bytes (256-bits) starting on a 32-byte boundary.
    24     Can't assume that rCHR is zero or that the cache line size is either
    25 @@ -158,6 +160,7 @@
    26  	add	rMEMP, rMEMP, rALIGN
    27  	b	L(medium_tail2)	/* 72nd instruction from .align */
    28  
    29 +#ifndef BROKEN_PPC_8xx_CPU15
    30  	.align	5
    31  	nop
    32  /* Clear cache lines of memory in 128-byte chunks.
    33 @@ -191,6 +194,7 @@
    34  	bdnz	L(zloop)
    35  	beqlr	cr5
    36  	b	L(medium_tail2)
    37 +#endif /* ! BROKEN_PPC_8xx_CPU15 */
    38  
    39  	.align	5
    40  L(small):
    41 @@ -248,6 +252,7 @@
    42  	stw	rCHR, -8(rMEMP)
    43  	blr
    44  
    45 +#ifndef BROKEN_PPC_8xx_CPU15
    46  L(checklinesize):
    47  #ifdef SHARED
    48  	mflr	rTMP
    49 @@ -329,6 +334,7 @@
    50  L(handletail32):
    51  	clrrwi.	rALIGN, rLEN, 5
    52  	b	L(nondcbz)
    53 +#endif /* ! BROKEN_PPC_8xx_CPU15 */
    54  
    55  END (BP_SYM (memset))
    56  libc_hidden_builtin_def (memset)