Currently, the DT-related settings are split out to
uniphier_of_serial_setup(), but it turned out to be not nice.
The next commit will add a DT property, but it will not fit in
the helper. Merge the helper into the probe function.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The FIFO size of the UART devices is 64 on almost all UniPhier SoCs
with the exception Pro4TV SoC (MN2WS0235), which used 128 FIFO size.
However, Pro4TV SoC was never upstreamed, and out of production.
So, this property has never been used in a useful way.
Let's remove old unused code.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The 8250 core uses the SCR as a canary to discover if the console has
been powered-off.
This hardware does not have SCR at offset 7, but an unused register
CHAR at a different offset. As long as the character interrupt is
disabled, the register access has no impact, so it is useful as an
alternative scratch register.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial8250_register_8250_port() may allocate a different port index
than requested. The driver needs to remember the returned value of
serial8250_register_8250_port() for later use. Otherwise, the .remove
hook may unregister a different port.
Fixes: 1a8d2903cb ("serial: 8250_uniphier: add UniPhier serial driver")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The hardware book says, the FCR is combined with a register called
CHAR (it will trigger interrupt when a specific character is
received). At first, I used lock/read/modify/write/unlock dance for
the FCR to not affect the upper bits, but the CHAR is actually never
used. It should not hurt to always clear the CHAR and to handle the
FCR as a normal case. It can save the costly locking.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For this driver, uart_port::regshift is always 2. Hardcode the
shift value instead of reading ->regshift to get an already known
value. (pointed out by Denys Vlasenko)
Furthermore, I am using register macros that are already shifted,
which will save code a bit.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At this point, 'value' is always a byte, then this code is clearing
bit 15, which is already clear. I meant to clear bit 7.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The !defined(MODULE) conditional has been added to the
OF_EARLYCON_DECLARE() define.
Now we can revert commit a2d3ea2f23 ("serial: 8250/uniphier:
fix modular build").
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The newly added uniphier serial port driver fails to build as
a loadable module when the base 8250 driver is built-in and
its console support enabled:
ERROR: "early_serial8250_setup" [drivers/tty/serial/8250/8250_uniphier.ko] undefined!
This changes the driver to only provide the early console support
if it is built-in itself as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reuses the code of drivers/tty/serial/8250/8250_early.c except
- Overwrite device->port.iotype and device->port.regshift for
UPIO_MEM32 because of_setup_earlycon() has set them for UPIO_MEM.
- Set device->baud to zero to prevent early8250_setup() from
initializing the divisor register because port->uartclk does not
match the frequency expected by this hardware.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The register offset must be shifted by regshift, otherwise the
baudrate is not set. I missed the issue probably because the
divisor register was already set by the boot loader.
Fixes: 1a8d2903cb ("serial: 8250_uniphier: add UniPhier serial driver")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add the driver for on-chip UART used on UniPhier SoCs.
This hardware is similar to 8250, but the register mapping is
slightly different:
- The offset to FCR, MCR is different.
- The divisor latch access bit does not exist. Instead, the
divisor latch register is available at offset 9.
This driver overrides serial_{in,out}, dl_{read,write} callbacks,
but wants to borrow most of code from 8250_core.c.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
