arch: remove blackfin port

The Analog Devices Blackfin port was added in 2007 and was rather
active for a while, but all work on it has come to a standstill
over time, as Analog have changed their product line-up.

Aaron Wu confirmed that the architecture port is no longer relevant,
and multiple people suggested removing blackfin independently because
of some of its oddities like a non-working SMP port, and the amount of
duplication between the chip variants, which cause extra work when
doing cross-architecture changes.

Link: https://docs.blackfin.uclinux.org/
Acked-by: Aaron Wu <Aaron.Wu@analog.com>
Acked-by: Bryan Wu <cooloney@gmail.com>
Cc: Steven Miao <realmz6@gmail.com>
Cc: Mike Frysinger <vapier@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 0 insertions, 16 deletions

diff --git a/Documentation/blackfin/bfin-spi-notes.txt b/Documentation/blackfin/bfin-spi-notes.txt
deleted file mode 100644
index eae6eaf2a09d..000000000000
--- a/Documentation/blackfin/bfin-spi-notes.txt
+++ /dev/null
@@ -1,16 +0,0 @@
-SPI Chip Select behavior:
-
-With the Blackfin on-chip SPI peripheral, there is some logic tied to the CPHA
-bit whether the Slave Select Line is controlled by hardware (CPHA=0) or
-controlled by software (CPHA=1). However, the Linux SPI bus driver assumes that
-the Slave Select is always under software control and being asserted during
-the entire SPI transfer. - And not just bits_per_word duration.
-
-In most cases you can utilize SPI MODE_3 instead of MODE_0 to work-around this
-behavior. If your SPI slave device in question requires SPI MODE_0 or MODE_2
-timing, you can utilize the GPIO controlled SPI Slave Select option instead.
-In this case, you should use GPIO based CS for all of your slaves and not just
-the ones using mode 0 or 2 in order to guarantee correct CS toggling behavior.
-
-You can even use the same pin whose peripheral role is a SSEL,
-but use it as a GPIO instead.