When the clock functions were changed to use cached values (and thereby
avoiding expensive math functions), early serial debug broke because the
baud programming is called before external memory is available.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
There is no code change here, just new comments, but this keeps me from
having to do another audit from scratch in the future.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Previously, booting over the UART required the baud rate to be known ahead
of time. Using a bit of tricky simple math, we can calculate the new board
rate based on the old divisors.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Some devices have no UART device pulled out, so allow people to disable the
driver completely in favor of other methods (like JTAG-console).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
We should use the algorithm in the Linux kernel so that the UART divisor
calculation is more accurate. It also fixes problems on some picky UARTs
that have sampling anomalies.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
All of the duplicated code for Blackfin processors and boot modes have been
unified. After all, the core is the same for all processors, just the
peripheral set differs (which gets handled in the drivers).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>