nmon is a tiny monitor (<1200 bytes) program
for the MIPS processors.
It can operate with NO working RAM at all!
It uses only the processor registers and NS16550-compatible
UART port for operation, so it can be used for a memory
controller setup code debugging.
With no changes nmon should work on different MIPS
processors as it uses only common MIPS-I instructions.
nmon is inspired by mmon, MIPS VR4300 Mini-monitor.
mmon is copyrighted 1996, 2003 by Eric Smith.
Also Alexander Voropay must be noted for his work
on qemu & YAMON mmon adaptations made in 2006 and 2007.
See http://www.brouhaha.com/~eric/software/mmon/
for mmon details.
The mmon's features missed in nmon:
* batch memory dumps;
* byte and 16-bit half-words dumps and stores;
* fill memory;
* load S-records (this function make sense only
if RAM works properly).
nmon has only 4 commands:
q - quit to barebox
d <addr> - read 32-bit word from <addr> address
w <addr> <val> - write 32-bit word <val> to <addr>
g <addr> - jump to <addr>
Addresses and data must be given in hexadecimal.
Everything (including hex digits 'a'..'f') must
be in lower case.
EXAMPLE: change value of word with address 0xa0000000
nmon> d a0000000
00000000
nmon> w a0000000 12345678
nmon> d a0000000
12345678
nmon>
There is no error checking of any kind. If you
give an invalid address you will probably get
an exception which will hang the board and you
will have to press the reset button.
You can interrupt current command (e.g. you have
made error in input <addr> value) by pressing
the <ESC> key.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
if E0 flag is not set, sdram is defenetly not configured.
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
The mips_barebox_10h macro inserts at offset 0x10
of the barebox image the string 'barebox ' followed
by compile time version mark.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Remove Shinya Kuribayashi's copyright on the ADR macro
in start-pbl.S as we don't define this macro in
this file or even use it where.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
The generated label usage make possible
to use the ADR macro many times.
If we don't use a generated label and we try
to use the ADR macro second time then we get
Error: symbol `_pc' is already defined
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
We already have the LONGSIZE macro definition in <asm/asm.h>.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
By default CONFIG_JZ4750D_DEBUG_LL_UART0 is selected.
This can confuse the Ritmix RZX50 user as the board
has only UART1 connected.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit moves the C debug_ll code from
the MIPS <debug_ll_ns16550.h> header file to
the MIPS <asm/debug_ll_ns16550.h> header file,
so the C code and the asm code can use the same
register address macros.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Set fake DEBUG_LL_UART_DIVISOR to use <asm/debug_ll_ns16550.h>.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Set DEBUG_LL_UART_DIVISOR to use <asm/debug_ll_ns16550.h>.
The JZ4755 uses 24 MHz as the main reference frequency (EXCLK).
The UART controller can work on full EXCLK or on EXCLK/2.
Just now we use EXCLK/2 legacy clock setup made by U-Boot.
So set UART controller base frequency to 12 MHz.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This patch adds macros for ns16550 port initialisation
and single char output. The macros can be used in
MIPS asm pbl code.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Ingenic JZ4755 SoC (JZ4750D family) has three UARTs.
So we can give to the user choose which one of them
to use for low level debug (debug_ll) output.
Also this commit adapts the only JZ4755 board
(Ritmix RZX50) for using the new debug_ll port
selection.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
In barebox we have no CONFIG_MIPS_MT_SMTC Kconfig option.
So remove the code under this macro.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Also enable the iomem and poweroff commands.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
The Ingenic JZ4740, JZ4755 and JZ4770 SoCs use
the same IP core for UART interface. This IP core
is NS16550-compatible, but it needs small workaround.
This commit moves the UART code for Ingenic SoCs
from board level to machine level. So the code
can be reused for different boards or even
different SoCs.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
On MIPS there are two segments in CPU address space that
can be used for untranslated memory access: KSEG0 and KSEG1.
KSEG0 is used for cached access and KSEG1 is used for
uncached one.
The instroduced mips_add_ram0() function registers two
address regions for memory access: one in KSEG0 and
the other one in KSEG1.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Add barebox-data section in arm branch to get complete
barebox regions in sdram regions tree.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Change function remap_range in arm architecture to make it
global accessable. For example command 'memtest' can change
pte flags to enable or disable cache.
Add dummy function for others architectures that doesn't
have mmu or pte support.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Trivial pbl support has no cpu specific setup.
We will add cache setup routines in the future.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This patch is based on ARM pbl support and allows
creating a pre-bootloader binary for compressed image.
For different MIPS SoCs (or even for different boards based
on the same SoC) the operations carried on in start-pbl.S
can be very different. The additional constraints can be imposed
on the size of the boot code or the special magic labels in
the beginning of the boot code; In some cases it could be
necessary to show CPU is alive as early as possible
(transmit a char via UART or blink a LED).
So the demands for pbl start operation can be very different.
E.g. malta board store boot code at the NOR flash mapped
to the MIPS power-on address (0xbfc00000); it is the most
simple case: we need just copy pbl image from direct-mapped
flash to RAM and jump there.
The XBurst-powered boards store boot code in the beginning
of a NAND flash or in the beginning of SD/MMC card.
In this case we must use simple and short NAND or SD/MMC access
routines to copy pbl image to RAM.
To meet so different demands a simple technique is selected:
* MIPS pbl entry point located in file arch/mips/boot/start-pbl.S.
* MIPS pbl code (see start-pbl.S) assumes that every pbl-enabled
board has a arch/mips/boards/<BOARD>/include/board/board_pbl_start.h
header file. This file must contain definition of
the board_pbl_start macro. This macro is used as start of pbl image;
* the most popular asm routines (stack setup, relocation to link
address, NS16550 initialization (WIP) and so on) are containt
in the arch/mips/include/asm/pbl_macros.h header file.
So board pbl macro can use it if necessary.
It is possible to create similar headers with macros for each
specific SoC; so even if we have many different boards based
on the same SoC the board_pbl_start macro for every board
can be short and clear.
* after board-specific initialization the stack pointer
is initialized and pbl C code is started.
Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Jean-Christophe PLAGNIOL-VILLARD
Antony Pavlov
Oleksij Rempel
Alexander Shiyan
Sascha Hauer
Alexander Aring