Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Earlycon calculates UART clock as "BASE_BAUD * 16". In case of ARC
"BASE_BAUD" is calculated dynamically in runtime, basically it is an
alias to arc_early_base_baud(), which in turn just does
"arc_base_baud/16".

8250 UART on AXS/SDP board uses 33.3MHz clock source which is set in
"arc_base_baud" with this change.

Additional compatibility string "snps,arc-sdp" is introduced as well
because there're different flavours of AXS boards but they all share the
same motherboard and so it's possible to re-use the same code for
motherbord even if CPU daughterboard changes.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Commit ffb7fcd66f14 ("ARC: Dynamically determine BASE_BAUD from DeviceTree")
breaks arc:defconfig build:

       drivers/built-in.o: In function `of_setup_earlycon':
       (.init.text+0xb3e): undefined reference to `arc_early_base_baud'
       drivers/built-in.o: In function `setup_earlycon':
       (.init.text+0xcd0): undefined reference to `arc_early_base_baud'
       make: *** [vmlinux] Error 1

BASE_BAUD is only required for earlycon, which should depend on
CONFIG_SERIAL_EARLYCON.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

8250 earlycon is broken on multi-platform ARC because the UART clk
value (BASE_BAUD) is fixed at build time.

Instead, determine the appropriate UART clk at runtime; parse the
devicetree early for platforms requiring alternate UART clk values
(currently only the TB10X platform).

Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Rob Herring <robh@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

Make of_get_flat_dt_prop arguments compatible with libfdt fdt_getprop
call in preparation to convert FDT code to use libfdt. Make the return
value const and the property length ptr type an int.

Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Stephen Chivers <schivers@csc.com>

Remove unnecessary prom.h includes in preparation to remove prom.h.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Grant Likely <grant.likely@linaro.org>

Convert arc to use the common of_flat_dt_match_machine function.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>

Convert arc to use new early_init_dt_scan function.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>

Use the common unflatten_and_copy_device_tree to copy the built-in FDT
out of init section.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Grant Likely <grant.likely@linaro.org>