linux.git/arch/openrisc/kernel/setup.c, branch v7.0

openrisc: Add jump label support

2025-09-11T10:27:59+00:00

Supported a complete jump_label implementation based on the ARM64 and
RV64 version and add the CONFIG_JUMP_LABEL=y to the defconfig.

Testing was conducted using a dedicated test module jump-label-test,
provided in the link below. For detailed steps, please refer to the
README also at the provided link.

Link: https://github.com/ChenMiaoi/GSoC-2025-Final-Report/tree/main/tests/jump-label-test

Test Environment:
  - Hardware: QEMU emulated OR1K
  - Kernel Version: 6.17.0-rc3-dirty
  - Configs: CONFIG_MODULES=y,CONFIG_MODULE_UNLOAD=y
  - Toolchain: or1k-none-linux-musl-gcc 15.1.0

Test Results:
$ insmod jump_label_test.ko
[   32.590000] Jump label performance test module loaded
[   35.250000] Normal branch time: 1241327150 ns (124 ns per iteration)
[   35.250000] Jump label (false) time: 706422700 ns (70 ns per iteration)
[   35.250000] Jump label (true) time: 708913450 ns (70 ns per iteration)
$ rmmod jump_label_test.ko
[   72.210000] Jump label test module unloaded

The results show approximately 43% improvement in branch performance
when using jump labels compared to traditional branches.

Link: https://lore.kernel.org/openrisc/aLsZ9S3X0OpKy1RM@antec/T/#u
Signed-off-by: chenmiao 
Signed-off-by: Stafford Horne

openrisc: Add cacheinfo support

2025-04-20T06:06:54+00:00

Add cacheinfo support for OpenRISC.

Currently, a few CPU cache attributes pertaining to OpenRISC processors
are exposed along with other unrelated CPU attributes in the procfs file
system (/proc/cpuinfo). However, a few cache attributes remain unexposed.

Provide a mechanism that the generic cacheinfo infrastructure can employ
to expose these attributes via the sysfs file system. These attributes
can then be exposed in /sys/devices/system/cpu/cpuX/cache/indexN. Move
the implementation to pull cache attributes from the processor's
registers from arch/openrisc/kernel/setup.c with a few modifications.

This implementation is based on similar work done for MIPS and LoongArch.

Link: https://raw.githubusercontent.com/openrisc/doc/master/openrisc-arch-1.4-rev0.pdf
Signed-off-by: Sahil Siddiq 
Signed-off-by: Stafford Horne

openrisc: Refactor struct cpuinfo_or1k to reduce duplication

2025-04-20T06:06:54+00:00

The "cpuinfo_or1k" structure currently has identical data members for
different cache components.

Remove these fields out of struct cpuinfo_or1k and into its own struct.
This reduces duplication while keeping cpuinfo_or1k extensible so more
cache descriptors can be added in the future.

Also add a new field "sets" to the new structure.

Signed-off-by: Sahil Siddiq 
Signed-off-by: Stafford Horne

openrisc: Call setup_memory() earlier in the init sequence

2024-03-10T08:55:46+00:00

The unflatten_and_copy_device_tree() function contains a call to
memblock_alloc(). This means that memblock is allocating memory before
any of the reserved memory regions are set aside in the setup_memory()
function which calls early_init_fdt_scan_reserved_mem(). Therefore,
there is a possibility for memblock to allocate from any of the
reserved memory regions.

Hence, move the call to setup_memory() to be earlier in the init
sequence so that the reserved memory regions are set aside before any
allocations are done using memblock.

Signed-off-by: Oreoluwa Babatunde 
Signed-off-by: Stafford Horne

openrisc: Use common of_get_cpu_node() instead of open-coding

2023-04-01T05:40:27+00:00

The common of_get_cpu_node() is equivalent to setup_find_cpu_node(), so
use it instead.

Signed-off-by: Rob Herring 
Signed-off-by: Stafford Horne

openrisc: Fix compiler warnings in setup

2021-08-10T21:14:23+00:00

This was pointed out with the recent name change of or32_early_setup to
or1k_early_setup.  Investigating the file I found a few other warnings
so cleaning them up here.

    arch/openrisc/kernel/setup.c:220:13: warning: no previous prototype for 'or1k_early_setup' [-Wmissing-prototypes]
      220 | void __init or1k_early_setup(void *fdt)
	  |             ^~~~~~~~~~~~~~~~

Fix this the missing or1k_early_setup prototype warning by adding an
asm/setup.h file to define the prototype.

    arch/openrisc/kernel/setup.c:246:13: warning: no previous prototype for 'detect_unit_config' [-Wmissing-prototypes]
      246 | void __init detect_unit_config(unsigned long upr, unsigned long mask,
	  |             ^~~~~~~~~~~~~~~~~~

The function detect_unit_config is not used, just remove it.

    arch/openrisc/kernel/setup.c:221: warning: Function parameter or member 'fdt' not described in 'or1k_early_setup'

Add @fdt docs to the function comment to suppress this warning.

Reported-by: kernel test robot 
Signed-off-by: Stafford Horne 
Reviewed-by: Randy Dunlap

openrisc: rename or32 code & comments to or1k

2021-08-05T01:53:59+00:00

From Documentation/openrisc/todo.rst, rename "or32" in the
source code to "or1k" since this is the name that has been
settled on.

Signed-off-by: Randy Dunlap 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: Stafford Horne 
Cc: openrisc@lists.librecores.org
Signed-off-by: Stafford Horne

openrisc: convert to setup_initial_init_mm()

2021-07-08T18:48:21+00:00

Use setup_initial_init_mm() helper to simplify code.

Link: https://lkml.kernel.org/r/20210608083418.137226-11-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang 
Acked-by: Stafford Horne 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: Stafford Horne 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

openrisc: Fix a memory leak

2021-04-28T12:40:44+00:00

'setup_find_cpu_node()' take a reference on the node it returns.
This reference must be decremented when not needed anymore, or there will
be a leak.

Add the missing 'of_node_put(cpu)'.

Note that 'setup_cpuinfo()' that also calls this function already has a
correct 'of_node_put(cpu)' at its end.

Fixes: 9d02a4283e9c ("OpenRISC: Boot code")
Signed-off-by: Christophe JAILLET 
Signed-off-by: Stafford Horne

h8300, nds32, openrisc: simplify detection of memory extents

2020-10-14T01:38:35+00:00

Instead of traversing memblock.memory regions to find memory_start and
memory_end, simply query memblock_{start,end}_of_DRAM().

Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Acked-by: Stafford Horne 
Cc: Andy Lutomirski 
Cc: Baoquan He 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Catalin Marinas 
Cc: Christoph Hellwig 
Cc: Daniel Axtens 
Cc: Dave Hansen 
Cc: Emil Renner Berthing 
Cc: Hari Bathini 
Cc: Ingo Molnar 
Cc: Ingo Molnar 
Cc: Jonathan Cameron 
Cc: Marek Szyprowski 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Michal Simek 
Cc: Miguel Ojeda 
Cc: Palmer Dabbelt 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Russell King 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Link: https://lkml.kernel.org/r/20200818151634.14343-6-rppt@kernel.org
Signed-off-by: Linus Torvalds