[PATCH v10 4/4] loongarch: Use new fallback IO memcpy/memset

From: Julian Vetter
Date: Mon Oct 21 2024 - 09:34:21 EST


Use the new fallback memcpy_{from,to}io and memset_io functions from
asm-generic/io.h on the loongarch processor architecture.

Reviewed-by: Yann Sionneau <ysionneau@xxxxxxxxxxxxx>
Signed-off-by: Julian Vetter <jvetter@xxxxxxxxxxxxx>
---
Changes for v10:
- Slightly updated commit message to clarify that on loongarch we now
use the fallback from asm-generic/io.h
---
arch/loongarch/include/asm/io.h | 10 ----
arch/loongarch/kernel/Makefile | 2 +-
arch/loongarch/kernel/io.c | 94 ---------------------------------
3 files changed, 1 insertion(+), 105 deletions(-)
delete mode 100644 arch/loongarch/kernel/io.c

diff --git a/arch/loongarch/include/asm/io.h b/arch/loongarch/include/asm/io.h
index 5e95a60df180..e77a56eaf906 100644
--- a/arch/loongarch/include/asm/io.h
+++ b/arch/loongarch/include/asm/io.h
@@ -62,16 +62,6 @@ static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,

#define mmiowb() wmb()

-/*
- * String version of I/O memory access operations.
- */
-extern void __memset_io(volatile void __iomem *dst, int c, size_t count);
-extern void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count);
-extern void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count);
-#define memset_io(c, v, l) __memset_io((c), (v), (l))
-#define memcpy_fromio(a, c, l) __memcpy_fromio((a), (c), (l))
-#define memcpy_toio(c, a, l) __memcpy_toio((c), (a), (l))
-
#define __io_aw() mmiowb()

#ifdef CONFIG_KFENCE
diff --git a/arch/loongarch/kernel/Makefile b/arch/loongarch/kernel/Makefile
index c9bfeda89e40..9497968ee158 100644
--- a/arch/loongarch/kernel/Makefile
+++ b/arch/loongarch/kernel/Makefile
@@ -8,7 +8,7 @@ OBJECT_FILES_NON_STANDARD_head.o := y
extra-y := vmlinux.lds

obj-y += head.o cpu-probe.o cacheinfo.o env.o setup.o entry.o genex.o \
- traps.o irq.o idle.o process.o dma.o mem.o io.o reset.o switch.o \
+ traps.o irq.o idle.o process.o dma.o mem.o reset.o switch.o \
elf.o syscall.o signal.o time.o topology.o inst.o ptrace.o vdso.o \
alternative.o unwind.o

diff --git a/arch/loongarch/kernel/io.c b/arch/loongarch/kernel/io.c
deleted file mode 100644
index cb85bda5a6ad..000000000000
--- a/arch/loongarch/kernel/io.c
+++ /dev/null
@@ -1,94 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
- */
-#include <linux/export.h>
-#include <linux/types.h>
-#include <linux/io.h>
-
-/*
- * Copy data from IO memory space to "real" memory space.
- */
-void __memcpy_fromio(void *to, const volatile void __iomem *from, size_t count)
-{
- while (count && !IS_ALIGNED((unsigned long)from, 8)) {
- *(u8 *)to = __raw_readb(from);
- from++;
- to++;
- count--;
- }
-
- while (count >= 8) {
- *(u64 *)to = __raw_readq(from);
- from += 8;
- to += 8;
- count -= 8;
- }
-
- while (count) {
- *(u8 *)to = __raw_readb(from);
- from++;
- to++;
- count--;
- }
-}
-EXPORT_SYMBOL(__memcpy_fromio);
-
-/*
- * Copy data from "real" memory space to IO memory space.
- */
-void __memcpy_toio(volatile void __iomem *to, const void *from, size_t count)
-{
- while (count && !IS_ALIGNED((unsigned long)to, 8)) {
- __raw_writeb(*(u8 *)from, to);
- from++;
- to++;
- count--;
- }
-
- while (count >= 8) {
- __raw_writeq(*(u64 *)from, to);
- from += 8;
- to += 8;
- count -= 8;
- }
-
- while (count) {
- __raw_writeb(*(u8 *)from, to);
- from++;
- to++;
- count--;
- }
-}
-EXPORT_SYMBOL(__memcpy_toio);
-
-/*
- * "memset" on IO memory space.
- */
-void __memset_io(volatile void __iomem *dst, int c, size_t count)
-{
- u64 qc = (u8)c;
-
- qc |= qc << 8;
- qc |= qc << 16;
- qc |= qc << 32;
-
- while (count && !IS_ALIGNED((unsigned long)dst, 8)) {
- __raw_writeb(c, dst);
- dst++;
- count--;
- }
-
- while (count >= 8) {
- __raw_writeq(qc, dst);
- dst += 8;
- count -= 8;
- }
-
- while (count) {
- __raw_writeb(c, dst);
- dst++;
- count--;
- }
-}
-EXPORT_SYMBOL(__memset_io);
--
2.34.1