[PATCH v4 3/5] Use generic io memcpy functions on the arm64 architecture

From: Julian Vetter
Date: Tue Sep 24 2024 - 05:25:30 EST


Use the generic __memcpy_{from,to}io and __memset_io functions on the
arm64 processor architecture.

Reviewed-by: Yann Sionneau <ysionneau@xxxxxxxxxxxxx>
Signed-off-by: Julian Vetter <jvetter@xxxxxxxxxxxxx>
---
arch/arm64/Kconfig | 1 +
arch/arm64/kernel/io.c | 87 ------------------------------------------
2 files changed, 1 insertion(+), 87 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a2f8ff354ca6..cfb1c729c9a1 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -140,6 +140,7 @@ config ARM64
select GENERIC_CPU_VULNERABILITIES
select GENERIC_EARLY_IOREMAP
select GENERIC_IDLE_POLL_SETUP
+ select GENERIC_IO_COPY
select GENERIC_IOREMAP
select GENERIC_IRQ_IPI
select GENERIC_IRQ_PROBE
diff --git a/arch/arm64/kernel/io.c b/arch/arm64/kernel/io.c
index ef48089fbfe1..fe86ada23c7d 100644
--- a/arch/arm64/kernel/io.c
+++ b/arch/arm64/kernel/io.c
@@ -9,34 +9,6 @@
#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);
-
/*
* This generates a memcpy that works on a from/to address which is aligned to
* bits. Count is in terms of the number of bits sized quantities to copy. It
@@ -78,62 +50,3 @@ void __iowrite32_copy_full(void __iomem *to, const void *from, size_t count)
dgh();
}
EXPORT_SYMBOL(__iowrite32_copy_full);
-
-/*
- * 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