[PATCH RFC 3/4] io-128-nonatomic: introduce io{read|write}128_{lo_hi|hi_lo}

[Chenghai Huang <huangchenghai2@huawei.com>]

From: Weili Qian <qianweili@huawei.com>

In order to provide non-atomic functions for io{read|write}128.
We define a number of variants of these functions in the generic
iomap that will do non-atomic operations.

These functions are only defined if io{read|write}128 are defined.
If they are not, then the wrappers that always use non-atomic operations
from include/linux/io-128-nonatomic*.h will be used.

Signed-off-by: Weili Qian <qianweili@huawei.com>
Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
---
 include/linux/io-128-nonatomic-hi-lo.h | 35 ++++++++++++++++++++++++++
 include/linux/io-128-nonatomic-lo-hi.h | 34 +++++++++++++++++++++++++
 2 files changed, 69 insertions(+)
 create mode 100644 include/linux/io-128-nonatomic-hi-lo.h
 create mode 100644 include/linux/io-128-nonatomic-lo-hi.h

diff --git a/include/linux/io-128-nonatomic-hi-lo.h b/include/linux/io-128-nonatomic-hi-lo.h
new file mode 100644
index 000000000000..b5b083a9e81b
--- /dev/null
+++ b/include/linux/io-128-nonatomic-hi-lo.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_IO_128_NONATOMIC_HI_LO_H_
+#define _LINUX_IO_128_NONATOMIC_HI_LO_H_
+
+#include <linux/io.h>
+#include <asm-generic/int-ll64.h>
+
+static inline u128 ioread128_hi_lo(const void __iomem *addr)
+{
+	u32 low, high;
+
+	high = ioread64(addr + sizeof(u64));
+	low = ioread64(addr);
+
+	return low + ((u128)high << 64);
+}
+
+static inline void iowrite128_hi_lo(u128 val, void __iomem *addr)
+{
+	iowrite64(val >> 64, addr + sizeof(u64));
+	iowrite64(val, addr);
+}
+
+#ifndef ioread128
+#define ioread128_is_nonatomic
+#define ioread128 ioread128_hi_lo
+#endif
+
+#ifndef iowrite128
+#define iowrite128_is_nonatomic
+#define iowrite128 iowrite128_hi_lo
+#endif
+
+#endif	/* _LINUX_IO_128_NONATOMIC_HI_LO_H_ */
+
diff --git a/include/linux/io-128-nonatomic-lo-hi.h b/include/linux/io-128-nonatomic-lo-hi.h
new file mode 100644
index 000000000000..0448ee5a13de
--- /dev/null
+++ b/include/linux/io-128-nonatomic-lo-hi.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_IO_128_NONATOMIC_LO_HI_H_
+#define _LINUX_IO_128_NONATOMIC_LO_HI_H_
+
+#include <linux/io.h>
+#include <asm-generic/int-ll64.h>
+
+static inline u128 ioread128_lo_hi(const void __iomem *addr)
+{
+	u64 low, high;
+
+	low = ioread64(addr);
+	high = ioread64(addr + sizeof(u64));
+
+	return low + ((u128)high << 64);
+}
+
+static inline void iowrite128_lo_hi(u128 val, void __iomem *addr)
+{
+	iowrite64(val, addr);
+	iowrite64(val >> 64, addr + sizeof(u64));
+}
+
+#ifndef ioread128
+#define ioread128_is_nonatomic
+#define ioread128 ioread128_lo_hi
+#endif
+
+#ifndef iowrite128
+#define iowrite128_is_nonatomic
+#define iowrite128 iowrite128_lo_hi
+#endif
+
+#endif	/* _LINUX_IO_128_NONATOMIC_LO_HI_H_ */
-- 
2.33.0