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Linux kernel
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several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
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This reverts commit bc7584e009c39375294794f7ca751a6b2622c425.
The split IPC system calls for o32 have been introduced with modern
version only. Changing this breaks ABI.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
pci-legacy systems are not using logic_pio to managed PIO
allocations, thus the generic pci_address_to_pio won't work
when PCI_IOBASE is defined.
Override the function to use architecture implementation to
fix the problem.
Cc: stable@vger.kernel.org
Fixes: 4bfb53e7d317 ("mips: add <asm-generic/io.h> including")
Reported-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Closes: https://lore.kernel.org/r/99f75c66-4c2d-45dc-a808-b5ba440c7551@app.fastmail.com/
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Remove hard-coded strings by using the str_on_off() helper function.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Commit 654102df2ac2 ("kbuild: add generic support for built-in boot
DTBs") introduced generic support for built-in DTBs.
Select GENERIC_BUILTIN_DTB and BUILTIN_DTB_ALL when the built-in DTB
support is enabled.
DTBs compiled under arch/mips/boot/dts/ will be wrapped by the generic
rule in scripts/Makefile.vmlinux.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
The commit 275f22148e87 ("ipc: rename old-style shmctl/semctl/msgctl
syscalls") switched various architectures to use sys_old_*ctl() with
ipc_parse_version, including mips n32/n64. However, for mips o32, commit
0d6040d46817 ("arch: add split IPC system calls where needed") added
separate IPC syscalls without properly using the old-style handlers.
This causes applications using uClibc-ng to fail with -EINVAL when
calling semctl/shmctl/msgctl with IPC_64 flag, as uClibc-ng uses the
syscall numbers from kernel headers to determine whether to use the IPC
multiplexer or split syscalls. In contrast, glibc is unaffected as it
uses a unified feature test macro __ASSUME_DIRECT_SYSVIPC_SYSCALLS
(disabled for mips-o32) to make this decision.
Fix this by switching the o32 ABI entries for semctl, shmctl and msgctl
to use the old-style handlers, matching the behavior of other
architectures and fixing compatibility with uClibc-ng.
Signed-off-by: Ism Hong <ism.hong@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Currently, installation of Debian 12.8 for mipsel fails on machines
without an FPU [1]. This is caused by the fact that zstd (which is used
for initramfs compression) executes the prefx instruction, which is not
emulated properly by the kernel.
The prefx (Prefetch Indexed) instruction fetches data from memory into
the cache without any side effects. Though functionally unrelated, it
requires an FPU [2].
Bytecode format of this instruction ends on "001111" binary:
(prefx instruction format) & 0x0000003f = 0x0000000f
The code in fpux_emu() runs like so:
#define MIPSInst(x) x
#define MIPSInst_FMA_FFMT(x) (MIPSInst(x) & 0x00000007)
#define MIPSInst_FUNC(x) (MIPSInst(x) & 0x0000003f)
enum cop1x_func { ..., pfetch_op = 0x0f, ... };
...
switch (MIPSInst_FMA_FFMT(ir)) {
...
case 0x3:
if (MIPSInst_FUNC(ir) != pfetch_op)
return SIGILL;
/* ignore prefx operation */
break;
default:
return SIGILL;
}
That snippet above contains a logic error and the
if (MIPSInst_FUNC(ir) != pfetch_op)
comparison always fires.
When MIPSInst_FUNC(ir) is equal to pfetch_op, ir must end on 001111
binary. In this case, MIPSInst_FMA_FFMT(ir) must be equal to 0x7, which
does not match that case label.
This causes emulation failure for the prefx instruction. Fix it.
This has been broken by
commit 919af8b96c89 ("MIPS: Make definitions of MIPSInst_FMA_{FUNC,FMTM} consistent with MIPS64 manual")
which modified the MIPSInst_FMA_FFMT macro without updating the users.
Signed-off-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Cc: stable@vger.kernel.org # after 3 weeks
Cc: Dengcheng Zhu <dzhu@wavecomp.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Fixes: 919af8b96c89 ("MIPS: Make definitions of MIPSInst_FMA_{FUNC,FMTM} consistent with MIPS64 manual")
[1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1091858
[2] MIPS Architecture For Programmers Volume II-A: The MIPS32 Instruction Set
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Clarify meanings of members of interface_info, especially for .size,
which does not define the ROM size.
Suggested-by: Icenowy Zheng <uwu@icenowy.me>
Signed-off-by: Kexy Biscuit <kexybiscuit@aosc.io>
Acked-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Per Appendix A.7 in Q/LS 0013-2014 (龙芯CPU开发系统固件与内核接口规范 V2.2,
lit. Loongson DevSys Firmware Kernel Interface Specification V2.2),
interface_info.size is size of this interface, not size of the LEFI BIOS
ROM.
In any case, the BIOS ROM Size just cannot be several kilobytes (KB) on
Loongson64 LEFI platforms.
Reported-by: Mingcong Bai <jeffbai@aosc.io>
Suggested-by: Icenowy Zheng <uwu@icenowy.me>
Fixes: 6c1bfbd9df8c ("MIPS: Loongson64: Add /sys/firmware/lefi/boardinfo")
Cc: stable@vger.kernel.org
Signed-off-by: Kexy Biscuit <kexybiscuit@aosc.io>
Acked-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Remove hard-coded strings by using the str_enabled_disabled() helper
function.
Use pr_info() instead of printk(KERN_INFO) to silence multiple
checkpatch warnings.
Suggested-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Declare ftrace_get_parent_ra_addr() as static to suppress clang
compiler warning that 'no previous prototype'. This function is
not intended to be called from other parts.
Fix follow error with clang-19:
arch/mips/kernel/ftrace.c:251:15: error: no previous prototype for function 'ftrace_get_parent_ra_addr' [-Werror,-Wmissing-prototypes]
251 | unsigned long ftrace_get_parent_ra_addr(unsigned long self_ra, unsigned long
| ^
arch/mips/kernel/ftrace.c:251:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
251 | unsigned long ftrace_get_parent_ra_addr(unsigned long self_ra, unsigned long
| ^
| static
1 error generated.
Signed-off-by: WangYuli <wangyuli@uniontech.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
This reverts commit 426fa8e4fe7bb914b5977cbce453a9926bf5b2e6.
The commit has caused two issues on Loongson 3A4000:
1. The timestamp in dmesg become erratic, like:
[3.736957] amdgpu 0000:04:00.0: ... ...
[3.748895] [drm] Initialized amdgpu ... ...
[18446744073.381141] amdgpu 0000:04:00:0: ... ...
[1.613326] igb 0000:03:00.0 enp3s0: ... ...
2. More seriously, some workloads (for example, the test
stdlib/test-cxa_atexit2 in the Glibc test suite) triggers an RCU
stall and hang the system with a high probably (4 hangs out of 5
tests).
Revert this commit to use jiffie on Loongson MIPS systems and fix these
issues for now. The root cause may need more investigation.
Cc: stable@vger.kernel.org # 6.11+
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Make a minor change to eliminate a static checker warning. The type
of cpu is unsigned int, so the correct format specifier should be
%u instead of %d.
Signed-off-by: liujing <liujing@cmss.chinamobile.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Add a blank line after __HEAD in the text section.
The __HEAD symbol was added in commit 52892ed6b03a ("MIPS:
Place __kernel_entry at the beginning of text section").
Signed-off-by: Rong Xu <xur@google.com>
Suggested-by: Maciej W. Rozycki <macro@orcam.me.uk>
---Changelog--
Added suggested-by.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
CP0 register 26 is used as ECC register for legacy cores, but newer
cores (MIPS32/MIPS64) use it as an ErrCtl register. Since the kernel only
uses CP0 26 as ErrCtl register rename the access functions to the more
fitting name.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Reviewed-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Pull i2c component probing support from Wolfram Sang:
"Add OF component probing.
Some devices are designed and manufactured with some components having
multiple drop-in replacement options. These components are often
connected to the mainboard via ribbon cables, having the same signals
and pin assignments across all options. These may include the display
panel and touchscreen on laptops and tablets, and the trackpad on
laptops. Sometimes which component option is used in a particular
device can be detected by some firmware provided identifier, other
times that information is not available, and the kernel has to try to
probe each device.
Instead of a delicate dance between drivers and device tree quirks,
this change introduces a simple I2C component probe function. For a
given class of devices on the same I2C bus, it will go through all of
them, doing a simple I2C read transfer and see which one of them
responds. It will then enable the device that responds"
* tag 'i2c-for-6.13-rc1-part3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
MAINTAINERS: fix typo in I2C OF COMPONENT PROBER
of: base: Document prefix argument for of_get_next_child_with_prefix()
i2c: Fix whitespace style issue
arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail
platform/chrome: Introduce device tree hardware prober
i2c: of-prober: Add GPIO support to simple helpers
i2c: of-prober: Add simple helpers for regulator support
i2c: Introduce OF component probe function
of: base: Add for_each_child_of_node_with_prefix()
of: dynamic: Add of_changeset_update_prop_string
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