[PATCH v2 06/12] lib/crc/mips: migrate mips-optimized CRC code into lib/crc/

Eric Biggers ebiggers at kernel.org
Sun Jun 8 06:04:48 AEST 2025


From: Eric Biggers <ebiggers at google.com>

Move the mips-optimized CRC code from arch/mips/lib/crc* into its new
location in lib/crc/mips/, and wire it up in the new way.  This new way
of organizing the CRC code eliminates the need to artificially split the
code for each CRC variant into separate arch and generic modules,
enabling better inlining and dead code elimination.  For more details,
see "lib/crc: prepare for arch-optimized code in subdirs of lib/crc/".

Signed-off-by: Eric Biggers <ebiggers at google.com>
---
 arch/mips/Kconfig                             |  1 -
 arch/mips/lib/Makefile                        |  2 --
 lib/crc/Kconfig                               |  1 +
 .../lib/crc32-mips.c => lib/crc/mips/crc32.h  | 33 ++++---------------
 4 files changed, 7 insertions(+), 30 deletions(-)
 rename arch/mips/lib/crc32-mips.c => lib/crc/mips/crc32.h (82%)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 1e48184ecf1ec..934eb961bd0dd 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -2022,11 +2022,10 @@ config CPU_MIPSR5
 	select MIPS_SPRAM
 
 config CPU_MIPSR6
 	bool
 	default y if CPU_MIPS32_R6 || CPU_MIPS64_R6
-	select ARCH_HAS_CRC32
 	select CPU_HAS_RIXI
 	select CPU_HAS_DIEI if !CPU_DIEI_BROKEN
 	select HAVE_ARCH_BITREVERSE
 	select MIPS_ASID_BITS_VARIABLE
 	select MIPS_SPRAM
diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile
index 9d75845ef78e1..8c40ffb09c420 100644
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -14,9 +14,7 @@ obj-$(CONFIG_PCI)	+= iomap-pci.o
 lib-$(CONFIG_GENERIC_CSUM)	:= $(filter-out csum_partial.o, $(lib-y))
 
 obj-$(CONFIG_CPU_GENERIC_DUMP_TLB) += dump_tlb.o
 obj-$(CONFIG_CPU_R3000)		+= r3k_dump_tlb.o
 
-obj-$(CONFIG_CRC32_ARCH)	+= crc32-mips.o
-
 # libgcc-style stuff needed in the kernel
 obj-y += bswapsi.o bswapdi.o multi3.o
diff --git a/lib/crc/Kconfig b/lib/crc/Kconfig
index c1629f07768f9..3f534fbfba951 100644
--- a/lib/crc/Kconfig
+++ b/lib/crc/Kconfig
@@ -67,10 +67,11 @@ config CRC32_ARCH
 	bool
 	depends on CRC32 && CRC_OPTIMIZATIONS
 	default y if ARM && KERNEL_MODE_NEON
 	default y if ARM64
 	default y if LOONGARCH
+	default y if MIPS && CPU_MIPSR6
 
 config CRC64
 	tristate
 	help
 	  The CRC64 library functions.  Select this if your module uses any of
diff --git a/arch/mips/lib/crc32-mips.c b/lib/crc/mips/crc32.h
similarity index 82%
rename from arch/mips/lib/crc32-mips.c
rename to lib/crc/mips/crc32.h
index 45e4d2c9fbf54..11cb272c63a69 100644
--- a/arch/mips/lib/crc32-mips.c
+++ b/lib/crc/mips/crc32.h
@@ -7,14 +7,10 @@
  * Copyright (C) 2014 Linaro Ltd <yazen.ghannam at linaro.org>
  * Copyright (C) 2018 MIPS Tech, LLC
  */
 
 #include <linux/cpufeature.h>
-#include <linux/crc32.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
 #include <asm/mipsregs.h>
 #include <linux/unaligned.h>
 
 #ifndef TOOLCHAIN_SUPPORTS_CRC
 #define _ASM_SET_CRC(OP, SZ, TYPE)					  \
@@ -62,11 +58,11 @@ do {							\
 #define CRC32C(crc, value, size) \
 	_CRC32(crc, value, size, crc32c)
 
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_crc32);
 
-u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
+static inline u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
 {
 	if (!static_branch_likely(&have_crc32))
 		return crc32_le_base(crc, p, len);
 
 	if (IS_ENABLED(CONFIG_64BIT)) {
@@ -104,13 +100,12 @@ u32 crc32_le_arch(u32 crc, const u8 *p, size_t len)
 		CRC32(crc, value, b);
 	}
 
 	return crc;
 }
-EXPORT_SYMBOL(crc32_le_arch);
 
-u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
+static inline u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
 {
 	if (!static_branch_likely(&have_crc32))
 		return crc32c_base(crc, p, len);
 
 	if (IS_ENABLED(CONFIG_64BIT)) {
@@ -147,37 +142,21 @@ u32 crc32c_arch(u32 crc, const u8 *p, size_t len)
 
 		CRC32C(crc, value, b);
 	}
 	return crc;
 }
-EXPORT_SYMBOL(crc32c_arch);
 
-u32 crc32_be_arch(u32 crc, const u8 *p, size_t len)
-{
-	return crc32_be_base(crc, p, len);
-}
-EXPORT_SYMBOL(crc32_be_arch);
+#define crc32_be_arch crc32_be_base /* not implemented on this arch */
 
-static int __init crc32_mips_init(void)
+#define crc32_mod_init_arch crc32_mod_init_arch
+static inline void crc32_mod_init_arch(void)
 {
 	if (cpu_have_feature(cpu_feature(MIPS_CRC32)))
 		static_branch_enable(&have_crc32);
-	return 0;
 }
-subsys_initcall(crc32_mips_init);
 
-static void __exit crc32_mips_exit(void)
-{
-}
-module_exit(crc32_mips_exit);
-
-u32 crc32_optimizations(void)
+static inline u32 crc32_optimizations_arch(void)
 {
 	if (static_key_enabled(&have_crc32))
 		return CRC32_LE_OPTIMIZATION | CRC32C_OPTIMIZATION;
 	return 0;
 }
-EXPORT_SYMBOL(crc32_optimizations);
-
-MODULE_AUTHOR("Marcin Nowakowski <marcin.nowakowski at mips.com");
-MODULE_DESCRIPTION("CRC32 and CRC32C using optional MIPS instructions");
-MODULE_LICENSE("GPL v2");
-- 
2.49.0



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