linux-stable.git/arch/loongarch/kernel/unaligned.c, branch linux-rolling-stable Linux kernel stable tree LoongArch: Adjust misc routines for 32BIT/64BIT 2025-12-08T10:09:17+00:00 Huacai Chen chenhuacai@loongson.cn 2025-12-08T10:09:17+00:00 b15dfdacd99dc0014413c71bc1157fc4e895ce68 Adjust misc routines for both 32BIT and 64BIT, including: bitops, bswap, checksum, string, jump label, unaligned access emulator, suspend/wakeup routines, etc. Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 
Adjust misc routines for both 32BIT and 64BIT, including: bitops, bswap,
checksum, string, jump label, unaligned access emulator, suspend/wakeup
routines, etc.

Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LoongArch: Add debugfs entries to switch SFB/TSO state 2025-01-26T13:49:59+00:00 Huacai Chen chenhuacai@loongson.cn 2025-01-26T13:49:59+00:00 04816c1507b46baccd17a4bc948440b3634d5d13 We need to switch SFB (Store Fill Buffer) and TSO (Total Store Order) state at runtime to debug memory management and KVM virtualization, so add two debugfs entries "sfb_state" and "tso_state" under the directory /sys/kernel/debug/loongarch. Query SFB: cat /sys/kernel/debug/loongarch/sfb_state Enable SFB: echo 1 > /sys/kernel/debug/loongarch/sfb_state Disable SFB: echo 0 > /sys/kernel/debug/loongarch/sfb_state Query TSO: cat /sys/kernel/debug/loongarch/tso_state Switch TSO: echo [TSO] > /sys/kernel/debug/loongarch/tso_state Available [TSO] states: 0 (No Load No Store) 1 (All Load No Store) 3 (Same Load No Store) 4 (No Load All Store) 5 (All Load All Store) 7 (Same Load All Store) Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 
We need to switch SFB (Store Fill Buffer) and TSO (Total Store Order)
state at runtime to debug memory management and KVM virtualization, so
add two debugfs entries "sfb_state" and "tso_state" under the directory
/sys/kernel/debug/loongarch.

Query SFB:
cat /sys/kernel/debug/loongarch/sfb_state

Enable SFB:
echo 1 > /sys/kernel/debug/loongarch/sfb_state

Disable SFB:
echo 0 > /sys/kernel/debug/loongarch/sfb_state

Query TSO:
cat /sys/kernel/debug/loongarch/tso_state

Switch TSO:
echo [TSO] > /sys/kernel/debug/loongarch/tso_state

Available [TSO] states:
0 (No Load No Store)    1 (All Load No Store)   3 (Same Load No Store)
4 (No Load All Store)   5 (All Load All Store)  7 (Same Load All Store)

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LoongArch: Delete unnecessary debugfs checking 2023-06-29T12:58:42+00:00 Dan Carpenter dan.carpenter@linaro.org 2023-06-29T12:58:42+00:00 d7c24960975b02211c53afe97c36acde5c8ff933 Debugfs functions are not supposed to be checked for errors. This is sort of unusual but it is described in the comments for the debugfs_create_dir() function. Also debugfs_create_dir() can never return NULL. Reviewed-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 
Debugfs functions are not supposed to be checked for errors.  This
is sort of unusual but it is described in the comments for the
debugfs_create_dir() function.  Also debugfs_create_dir() can never
return NULL.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LoongArch: Fix debugfs_create_dir() error checking 2023-06-15T06:35:56+00:00 Immad Mir mirimmad17@gmail.com 2023-06-15T06:35:56+00:00 41efbb682de1231c3f6361039f46ad149e3ff5b9 The debugfs_create_dir() returns ERR_PTR in case of an error and the correct way of checking it is using the IS_ERR_OR_NULL inline function rather than the simple null comparision. This patch fixes the issue. Cc: stable@vger.kernel.org Suggested-By: Ivan Orlov <ivan.orlov0322@gmail.com> Signed-off-by: Immad Mir <mirimmad17@gmail.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 
The debugfs_create_dir() returns ERR_PTR in case of an error and the
correct way of checking it is using the IS_ERR_OR_NULL inline function
rather than the simple null comparision. This patch fixes the issue.

Cc: stable@vger.kernel.org
Suggested-By: Ivan Orlov <ivan.orlov0322@gmail.com>
Signed-off-by: Immad Mir <mirimmad17@gmail.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
LoongArch: Add unaligned access support 2022-12-14T00:36:11+00:00 Huacai Chen chenhuacai@loongson.cn 2022-12-10T14:39:59+00:00 61a6fccc0bd2e8030b2672a52ef3f6706b2b2ee4 Loongson-2 series (Loongson-2K500, Loongson-2K1000) don't support unaligned access in hardware, while Loongson-3 series (Loongson-3A5000, Loongson-3C5000) are configurable whether support unaligned access in hardware. This patch add unaligned access emulation for those LoongArch processors without hardware support. Signed-off-by: Huacai Chen <chenhuacai@loongson.cn> 
Loongson-2 series (Loongson-2K500, Loongson-2K1000) don't support
unaligned access in hardware, while Loongson-3 series (Loongson-3A5000,
Loongson-3C5000) are configurable whether support unaligned access in
hardware. This patch add unaligned access emulation for those LoongArch
processors without hardware support.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>