[PATCH 2/3] asm-generic/io.h: API for 128-bit memory accessors

From: Yury Norov
Date: Wed Jan 24 2018 - 04:07:06 EST


Some architectures, like arm64, support 128-bit memory access. For
ARM64 - using load/store pair instructions. This patch introduces
reado() and writeo() functions family, where suffix 'o' stands for
reading and writing the octet of bytes at once.

Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx>
---
include/asm-generic/io.h | 147 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 147 insertions(+)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index b4531e3b2120..ac4a4de69efc 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -67,6 +67,16 @@ static inline u64 __raw_readq(const volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef __raw_reado
+#define __raw_reado __raw_reado
+static inline __uint128_t __raw_reado(const volatile void __iomem *addr)
+{
+ return *(const volatile __uint128_t __force *)addr;
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef __raw_writeb
#define __raw_writeb __raw_writeb
static inline void __raw_writeb(u8 value, volatile void __iomem *addr)
@@ -101,6 +111,16 @@ static inline void __raw_writeq(u64 value, volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef __raw_writeo
+#define __raw_writeo __raw_writeo
+static inline void __raw_writeo(__uint128_t value, volatile void __iomem *addr)
+{
+ *(volatile __uint128_t __force *)addr = value;
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
/*
* {read,write}{b,w,l,q}() access little endian memory and return result in
* native endianness.
@@ -140,6 +160,16 @@ static inline u64 readq(const volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef reado
+#define reado reado
+static inline __uint128_t reado(const volatile void __iomem *addr)
+{
+ return __le128_to_cpu(__raw_reado(addr));
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef writeb
#define writeb writeb
static inline void writeb(u8 value, volatile void __iomem *addr)
@@ -174,6 +204,16 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef writeo
+#define writeo writeo
+static inline void writeo(__uint128_t value, volatile void __iomem *addr)
+{
+ __raw_writeo(__cpu_to_le128(value), addr);
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
/*
* {read,write}{b,w,l,q}_relaxed() are like the regular version, but
* are not guaranteed to provide ordering against spinlocks or memory
@@ -195,6 +235,10 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
#define readq_relaxed readq
#endif

+#if defined(reado) && !defined(reado_relaxed)
+#define reado_relaxed reado
+#endif
+
#ifndef writeb_relaxed
#define writeb_relaxed writeb
#endif
@@ -211,6 +255,10 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
#define writeq_relaxed writeq
#endif

+#if defined(writeo) && !defined(writeo_relaxed)
+#define writeo_relaxed writeo
+#endif
+
/*
* {read,write}s{b,w,l,q}() repeatedly access the same memory address in
* native endianness in 8-, 16-, 32- or 64-bit chunks (@count times).
@@ -281,6 +329,24 @@ static inline void readsq(const volatile void __iomem *addr, void *buffer,
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef readso
+#define readso readso
+static inline void readso(const volatile void __iomem *addr, void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ __uint128_t *buf = buffer;
+
+ do {
+ __uint128_t x = __raw_reado(addr);
+ *buf++ = x;
+ } while (--count);
+ }
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef writesb
#define writesb writesb
static inline void writesb(volatile void __iomem *addr, const void *buffer,
@@ -343,6 +409,23 @@ static inline void writesq(volatile void __iomem *addr, const void *buffer,
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef writeso
+#define writeso writeso
+static inline void writeso(volatile void __iomem *addr, const void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ const __uint128_t *buf = buffer;
+
+ do {
+ __raw_writeo(*buf++, addr);
+ } while (--count);
+ }
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef PCI_IOBASE
#define PCI_IOBASE ((void __iomem *)0)
#endif
@@ -595,6 +678,16 @@ static inline u64 ioread64(const volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef ioread128
+#define ioread128 ioread128
+static inline __uint128_t ioread128(const volatile void __iomem *addr)
+{
+ return reado(addr);
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef iowrite8
#define iowrite8 iowrite8
static inline void iowrite8(u8 value, volatile void __iomem *addr)
@@ -629,6 +722,16 @@ static inline void iowrite64(u64 value, volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef iowrite128
+#define iowrite128 iowrite128
+static inline void iowrite128(__uint128_t value, volatile void __iomem *addr)
+{
+ writeo(value, addr);
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef ioread16be
#define ioread16be ioread16be
static inline u16 ioread16be(const volatile void __iomem *addr)
@@ -655,6 +758,16 @@ static inline u64 ioread64be(const volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef ioread128be
+#define ioread128be ioread128be
+static inline __uint128_t ioread128be(const volatile void __iomem *addr)
+{
+ return swab128(reado(addr));
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef iowrite16be
#define iowrite16be iowrite16be
static inline void iowrite16be(u16 value, void volatile __iomem *addr)
@@ -681,6 +794,16 @@ static inline void iowrite64be(u64 value, volatile void __iomem *addr)
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef iowrite128be
+#define iowrite128be iowrite128be
+static inline void iowrite128be(__uint128_t value, volatile void __iomem *addr)
+{
+ writeo(swab128(value), addr);
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef ioread8_rep
#define ioread8_rep ioread8_rep
static inline void ioread8_rep(const volatile void __iomem *addr, void *buffer,
@@ -719,6 +842,17 @@ static inline void ioread64_rep(const volatile void __iomem *addr,
#endif
#endif /* CONFIG_64BIT */

+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef ioread128_rep
+#define ioread128_rep ioread128_rep
+static inline void ioread128_rep(const volatile void __iomem *addr,
+ void *buffer, unsigned int count)
+{
+ readso(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#ifndef iowrite8_rep
#define iowrite8_rep iowrite8_rep
static inline void iowrite8_rep(volatile void __iomem *addr,
@@ -760,6 +894,19 @@ static inline void iowrite64_rep(volatile void __iomem *addr,
}
#endif
#endif /* CONFIG_64BIT */
+
+#ifdef CONFIG_HAVE_128BIT_ACCESS
+#ifndef iowrite128_rep
+#define iowrite128_rep iowrite128_rep
+static inline void iowrite128_rep(volatile void __iomem *addr,
+ const void *buffer,
+ unsigned int count)
+{
+ writeso(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_HAVE_128BIT_ACCESS */
+
#endif /* CONFIG_GENERIC_IOMAP */

#ifdef __KERNEL__
--
2.11.0