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2012-07-20s390/comments: unify copyright messages and remove file namesHeiko Carstens
Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-03-18[S390] __div64_31 broken for CONFIG_MARCH_G5Martin Schwidefsky
The implementation of __div64_31 for G5 machines is broken. The comments in __div64_31 are correct, only the code does not do what the comments say. The part "If the remainder has overflown subtract base and increase the quotient" is only partially realized, the base is subtracted correctly but the quotient is only increased if the dividend had the last bit set. Using the correct instruction fixes the problem. Cc: stable@kernel.org Reported-by: Frans Pop <elendil@planet.nl> Tested-by: Frans Pop <elendil@planet.nl> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-04-25[S390]: Fix build on 31-bit.David S. Miller
Allow s390 to properly override the generic __div64_32() implementation by: 1) Using obj-y for div64.o in s390's makefile instead of lib-y 2) Adding the weak attribute to the generic implementation. Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28[S390] __div64_32 for 31 bit.Martin Schwidefsky
The clocksource infrastructure introduced with commit ad596171ed635c51a9eef829187af100cbf8dcf7 broke 31 bit s390. The reason is that the do_div() primitive for 31 bit always had a restriction: it could only divide an unsigned 64 bit integer by an unsigned 31 bit integer. The clocksource code now uses do_div() with a base value that has the most significant bit set. The result is that clock->cycle_interval has a funny value which causes the linux time to jump around like mad. The solution is "obvious": implement a proper __div64_32 function for 31 bit s390. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>