If the counter overflows during a __delay operation, we will exit the
loop prematurely. For example, calling __delay(0x100) with the counter
at 0xffffff00 gives us a target of 0x0. The unsigned comparison in the
while loop will likely be false on the first iteration (if the counter
is now anything other than 0) and we will return early.
This patch fixes the problem by comparing deltas in the loop rather than
absolute values.
Cc: Jon Masters <jcm@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
The openrisc implementation of __const_udelay casts the result of a
32-bit multiplication to 64 bits and passes the top 32 bits to __delay.
Since there are no casts on the arguments, this results in a __delay of
zero, regardless of the xloops parameter.
This patch fixes the problem by casting xloops to (unsigned long long),
ensuring that the multiplication is not truncated.
Cc: Jon Masters <jcm@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonas Bonn <jonas@southpole.se>
The generic version is both easier to support and more correct.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As per commits 2922585b93 ("lib: Sparc's strncpy_from_user is generic
enough, move under lib/") and 92ae03f2ef ("x86: merge 32/64-bit
versions of 'strncpy_from_user()' and speed it up"), and corresponding
discussion on linux-arch.
Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Will Deacon