Octeon has a specific boot header, when booted via SPI NOR, NAND or MMC.
Here the only 2 instructions are allowed in the first few bytes of the
image. And these instructions need to be one branch and a nop. This
patch adds the necessary nop after the nop, to that the common MIPS
image is compatible with this Octeon header.
The tool to patch the Octeon boot header into the image will be send in
a follow-up patch.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Aaron Williams <awilliams@marvell.com>
Cc: Chandrakala Chavva <cchavva@marvell.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
This patch adds the optional call to mips_mach_early_init() to start.S
at a very early stage. Its disabled per default. It can be used for
very early machine / platform specific init code. Its called very
early and at this stage the PC is allowed to differ from the linking
address (CONFIG_TEXT_BASE) as no absolute jump has been performed until
this call.
It will be used by thje Octeon platform.
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Sync asm/mipsregs.h with Linux 5.7. Also replace the custom
symbols EBASE_CPUNUM and EBASE_WG with the according symbols
from Linux.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
Add an own Kconfig symbol for the initial disabling of caches
invoked from generic start code.
Also add an own Kconfig symbols for the initialization of caches
invoked from generic start code.
Until now both code paths could only be disabled with
CONFIG_SKIP_LOWLEVEL_INIT. But this is not flexible enough for
RAM boot scenarios like EJTAG or SPL payload or for machines
which don't require cache initialization or which want to
provide their own cache implementation.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
Logically this code belongs to cache_init.S.
If a complex SoC needs to replace the generic cache init,
mips_cache_disable() can now be called from custom start.S files.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
Since commit 703ec9ddf9 ("MIPS: Stop building position independent code")
the relocation code was completely reworked and removed from start.S.
Remove some left-overs of the old code.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
The initial stack on some platforms is too small to hold a large malloc
space. This patch adds a option to allow these platforms not reserving the
malloc space on initial stack. These platforms should set the malloc base
after DRAM is usable.
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
Currently CONFIG_MIPS_INIT_STACK_IN_SRAM assumes the memory space for the
initial stack can be used directly. However on some platform the SRAM needs
initialization, e.g. lock cache.
This patch adds an option to allow a new function mips_sram_init() being
called before setup_stack_gd.
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
When setting up initial stack, global data will also be put in the stack,
and being cleared.
The assembler instructions for clearing gd is as follows:
move t0, k0
1:
PTR_S zero, 0(t0)
blt t0, t1, 1b
PTR_ADDIU t0, PTRSIZE
t0 is the start address of gd, t1 is the end address of gd (t0 + GD_SIZE).
[PTR_ADDIU t0, PTRSIZE] is in the delay slot of [blt t0, t1, 1b], so it
will be executed before the branch operation.
However the comparison for the BLT instruction is done before executing the
delay slot. This means when the last word just before k1 is cleared, the
loop will continue to run once. This will clear an extra word at k1, which
is outside the global data.
Global data is placed at the top of the stack. If the initial stack is a
SRAM or locked cache, the area outside them may be inaccessible. A write
operation performed in this area may cause an exception.
To solve this, [PTR_ADDIU t0, PTRSIZE] should be placed before the BLT
instruction.
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
Some MIPS systems store some board-specific boot configuration
in the U-Boot binary at offset 0x10. This is used by Malta boards
and by Lantiq/Intel SoC's when booting from parallel NOR flash.
Convert the hard-coded values to Kconfig options to remove such
board-specific stuff out of the generic start.S code. This also
deprecates the config option CONFIG_SYS_XWAY_EBU_BOOTCFG.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.
In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.
This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.
Signed-off-by: Tom Rini <trini@konsulko.com>
Some platforms have very limited SRAM to run SPL code, so there may
not be the same amount space for a malloc pool before relocation in
the SPL stage as the normal U-Boot stage.
Make SPL and (the full) U-Boot stage use independent SYS_MALLOC_F_LEN,
so the size of pre-relocation malloc pool can be configured memory
space independently.
Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Acked-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Acked-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
[fixed up commit-message:]
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
U-Boot has up until now built with -fpic for the MIPS architecture,
producing position independent code which uses indirection through a
global offset table, making relocation fairly straightforward as it
simply involves patching up GOT entries.
Using -fpic does however have some downsides. The biggest of these is
that generated code is bloated in various ways. For example, function
calls are indirected through the GOT & the t9 register:
8f998064 lw t9,-32668(gp)
0320f809 jalr t9
Without -fpic the call is simply:
0f803f01 jal be00fc04 <puts>
This is more compact & faster (due to the lack of the load & the
dependency the jump has on its result). It is also easier to read &
debug because the disassembly shows what function is being called,
rather than just an offset from gp which would then have to be looked up
in the ELF to discover the target function.
Another disadvantage of -fpic is that each function begins with a
sequence to calculate the value of the gp register, for example:
3c1c0004 lui gp,0x4
279c3384 addiu gp,gp,13188
0399e021 addu gp,gp,t9
Without using -fpic this sequence no longer appears at the start of each
function, reducing code size considerably.
This patch switches U-Boot from building with -fpic to building with
-fno-pic, in order to gain the benefits described above. The cost of
this is an extra step during the build process to extract relocation
data from the ELF & write it into a new .rel section in a compact
format, plus the added complexity of dealing with multiple types of
relocation rather than the single type that applied to the GOT. The
benefit is smaller, cleaner, more debuggable code. The relocate_code()
function is reimplemented in C to handle the new relocation scheme,
which also makes it easier to read & debug.
Taking maltael_defconfig as an example the size of u-boot.bin built
using the Codescape MIPS 2016.05-06 toolchain (gcc 4.9.2, binutils
2.24.90) shrinks from 254KiB to 224KiB.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: u-boot@lists.denx.de
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Tested-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
CFE checks CPU Thread in a different way (using register $22):
mfc0 t1, C0_BCM_CONFIG, 3 # $22
li t2, CP0_CMT_TPID # (1 << 31)
and t1, t2
bnez t1, 2f # if we are running on thread 1, skip init
nop
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
All MIPS boards that support debug uart are calling debug_uart_init right at
the beginning of board_early_init_f.
Instead of doing that, let's provide a generic call to debug_uart_init right
before the call to board_init_f if debug uart is enabled for boards without
stack in SRAM.
On the other hand, boards with stack in SRAM can call earlier (right before
low level init).
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
This adds a new Kconfig option CONFIG_MIPS_INIT_STACK_IN_SRAM which
a SoC can select if it supports some kind of SRAM. Together with
CONFIG_SYS_INIT_SP_ADDR the initial stack and global data can be
set up in that SRAM. This can be used to provide a C environment
also for lowlevel_init().
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Move the code for setting up the initial stack and global data
to a macro to be able to use it more than once.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Clear cp0 status while preserving implementation specific bits.
Set bits BEV and ERL as the arch specification requires after
a reset or soft-reset exception.
Extend and fix initialization of watch registers. Check if additional
watch register sets are implemented and initialize them too.
Initialize cp0 count as early as possible to get the most
accurate boot timing.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
When booting from ROM, early exceptions can't be handled
properly. Instead of busy-looping give the developer the
possibilty to examine the situation. Invoke an UHI
exception operation which can be read as unhandled exception
by a hardware debugger if one is attached. If the debugger
doesn't support UHI, the exception is read as unexpected
breakpoint.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
This adds a compile time option to include code for static
exception vectors. Static exception vectors are only needed,
when the U-Boot entry point is equal to the CPU reset exception
vector address. For instance this is the case when U-Boot is
used as ROM in Qemu or booted from parallel NOR flash. When
U-Boot is booted from RAM (e.g. loaded there by SPL), the
exception vectors need to be setup dynamically, which is done
in follow-up commits.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Some systems are configured such that multiple CPUs begin running from
their reset vector following a system reset. If this occurs then U-Boot
will be run on multiple CPUs simultaneously, which causes all sorts of
issues as the multiple instances of U-Boot clobber each other.
Prevent this from happening by simply hanging with an infinite loop if
we run on a CPU whose ID, as determined by GlobalNumber or EBase.CPUNum
as appropriate, is non-zero.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
The relocate_code function was handling cache maintenance incorrectly.
It copied U-Boot to its new location, flushed the caches & then
proceeded to apply relocations & jump to the new code without flushing
the caches again. This is problematic as the instruction cache could
potentially have already fetched instructions that hadn't had relocs
applied.
Rework this to perform the flush_cache call using the code in the
original copy of U-Boot, after having applied relocations to the new
copy of U-Boot. The new U-Boot can then be jumped to safely once that
cache flush has been performed.
As part of this, since the old U-Boot is used up until after that cache
flush, complexity around loading values from the GOT using a jump & link
instruction & loads from a table is removed. Instead we can simply load
the needed values with PTR_LA fromt the original GOT.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
During boot we set Config.K0=2 (uncached) such that any accesses to the
kseg0 memory region are performed uncached before the caches are
initialised. This write to the Config register introduces an execution
hazard between it & any following memory accesses (such as the load of
_gp), which we need to clear in order to ensure those memory accesses
are actually performed uncached. Clear this execution hazard with the
insertion of an ehb execution hazard barrier instruction.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Map the Global Control Registers (GCRs) provided by the MIPS Coherence
Manager (CM) in preparation for using some of them in later patches.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
On systems where cache initialisation doesn't require zeroed memory (ie.
systems where CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD is not defined)
perform cache initialisation prior to lowlevel_init & DDR
initialisation. This allows for DDR initialisation code to run cached &
thus significantly faster.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
The coprocessor 0 Config register includes 9 implementation defined
bits, which in some processors do things like enable write combining or
other functionality. We ought not to wipe them to 0 during boot. Rather
than doing so, preserve their value & only clear the bits standardised
by the MIPS architecture.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Enable use of the instruction cache immediately after it has been
initialised. This will only take effect if U-Boot was linked to run from
kseg0 rather than kseg1, but when this is the case the data cache
initialisation code will run cached & thus significantly faster.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
In MIPS assembly there have historically been 2 variants of immediate
addition - the standard "addi" which traps if an overflow occurs, and
the unchecked "addiu" which does not trap on overflow. In release 6 of
the MIPS architecture the trapping variants of immediate addition &
subtraction have been removed. In preparation for supporting MIPSr6,
stop using the trapping instructions from assembly & switch to their
unchecked variants.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Correct spelling of "U-Boot" shall be used in all written text
(documentation, comments in source files etc.).
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Minkyu Kang <mk7.kang@samsung.com>
Fix 32 vs 64 bit load/store instructions. Access CP0_WATCHHI as
32 Bit register. Use 64 Bit register access for clearing gd_data
and copying U-Boot.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Argument boot_flags of board_init_f() should be set to 0 as
$a0 may be utilized in lowlevel_init() or mips_cache_reset()
or previous stage boot-loader.
Signed-off-by: Purna Chandra Mandal <purna.mandal@microchip.com>
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Correctly annotate _start and relocate_code as functions to
produce more readable disassembly code generated by objdump.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Unify and move code in arch/mips/cpu/mips[32|64]/ to arch/mips/cpu/.
The CPU specific config.mk files need to remain until
CONFIG_STANDALONE_LOAD_ADDR is converted to a global Kconfig symbol.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
All current CPUs and SoCs are based on MIPS32 arch. The complete
code resides in the global arch/mips/cpu directory. This is not
suitable if other MIPS architectures like MIPS64 or Octeon should
be supported in the future.
To achieve this the current CPU code is moved to its own mips32
subdirectory. All MIPS32 boards have to use mips32 as config switch
in board.cfg.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Stefan Roese <sr@denx.de>
Cc: Thomas Lange <thomas@corelatus.se>
Cc: Vlad Lungu <vlad.lungu@windriver.com>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
The Purple SoC and eval board are not actively maintained since years.
This patch removes the support completely as aggreed with Wolfgang Denk.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@googlemail.com>
Cc: Wolfgang Denk <wd@denx.de>
Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
CONFIG_SYS_GBL_DATA_SIZE has always been just a bad workarond for not
being able to use "sizeof(struct global_data)" in assembler files.
Recent experience has shown that manual synchronization is not
reliable enough. This patch renames CONFIG_SYS_GBL_DATA_SIZE into
GENERATED_GBL_DATA_SIZE which gets automatically generated by the
asm-offsets tool. In the result, all definitions of this value can be
deleted from the board config files. We have to make sure that all
files that reference such data include the new <asm-offsets.h> file.
No other changes have been done yet, but it is obvious that similar
changes / simplifications can be done for other, related macro
definitions as well.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
