On Fri, Mar 15, 2013 at 06:25:49PM +0100, Michael Holzheu wrote: > Hello Simon, > > From the "Principles of Operations" (the s390 bible): > > The first operand is compared with the second operand, and the result > is indicated in the condition code. > > For COMPARE LOGICAL IMMEDIATE (CLGFI), the first operand is treated as > 64 bits, and the second operand is treated as 32 bits with 32 zeros > appended on the left. > > This instruction works with 32 bit immediate values. > > For COMPARE HALFWORD IMMEDIATE (CGHI), the first operand is treated as > a 64-bit signed binary integer. > > This instruction works only with 16 bit immediate values. > > See: > > http://pic.dhe.ibm.com/infocenter/ratdevz/v8r0/topic/com.ibm.tpf.toolkit.hlasm.doc/dz9zr006.pdf > > Because I only want to check against zero the two instructions will > have the same effect in the purgatory code. Thanks. I have applied the change. > Michael > > > On Fri, 15 Mar 2013 16:57:33 +0100 > Simon Horman <horms at verge.net.au> wrote: > > > On Fri, Mar 15, 2013 at 01:46:32PM +0100, Michael Holzheu wrote: > > > The clgfi instruction needs at least z9 machine level. To allow > > > kexec-tools compiled also with z900, this patch replaces clgfi with > > > the older cghi instruction. > > > > Hi, > > > > could you update the changelog to include a brief description of the > > difference between the two instructions - I assume they work the same > > way in the context of this change. > > > > > Signed-off-by: Michael Holzheu <holzheu at linux.vnet.ibm.com> > > > --- > > > purgatory/arch/s390/setup-s390.S | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > Index: kexec-tools-2.0.3/purgatory/arch/s390/setup-s390.S > > > =================================================================== > > > --- kexec-tools-2.0.3.orig/purgatory/arch/s390/setup-s390.S > > > +++ kexec-tools-2.0.3/purgatory/arch/s390/setup-s390.S > > > @@ -16,7 +16,7 @@ purgatory_start: > > > larl %r15,lstack_end > > > aghi %r15,-160 > > > > > > - clgfi %r2,0 > > > + cghi %r2,0 > > > je verify_checksums > > > > > > brasl %r14,purgatory > > > > > > > > > _______________________________________________ > > > kexec mailing list > > > kexec at lists.infradead.org > > > http://lists.infradead.org/mailman/listinfo/kexec > > > > > >
