[PATCH 01/11] lib: Import iomem_copy from Linux Kernel

[Peng Fan (OSS)]

From: Peng Fan <peng.fan at nxp.com>

memcpy_{from,to}io and memset_io is needed for i.MX8M to write
TCM area. So import the APIs from Linux Kernel 6.17.

Reviewed-by: Ye Li <ye.li at nxp.com>
Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 include/asm-generic/io.h |  37 +++++++++++++
 lib/Makefile             |   1 +
 lib/iomem_copy.c         | 136 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 174 insertions(+)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 13d99cfb5973399209c00adee0080ff83414c064..cf981ad3501f935c714b7580536540e7aba249c1 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -3,6 +3,7 @@
  * Generic I/O functions.
  *
  * Copyright (c) 2016 Imagination Technologies Ltd.
+ * Copyright 2025 NXP
  */
 
 #ifndef __ASM_GENERIC_IO_H__
@@ -453,5 +454,41 @@ static inline void iowrite64_rep(volatile void __iomem *addr,
 #endif
 #endif /* CONFIG_64BIT */
 
+#ifndef memset_io
+/**
+ * memset_io -	Set a range of I/O memory to a constant value
+ * @addr:	The beginning of the I/O-memory range to set
+ * @val:	The value to set the memory to
+ * @count:	The number of bytes to set
+ *
+ * Set a range of I/O memory to a given value.
+ */
+void memset_io(volatile void __iomem *addr, int val, size_t count);
+#endif
+
+#ifndef memcpy_fromio
+/**
+ * memcpy_fromio -	Copy a block of data from I/O memory
+ * @dst:		The (RAM) destination for the copy
+ * @src:		The (I/O memory) source for the data
+ * @count:		The number of bytes to copy
+ *
+ * Copy a block of data from I/O memory.
+ */
+void memcpy_fromio(void *dst, const volatile void __iomem *src, size_t count);
+#endif
+
+#ifndef memcpy_toio
+/**
+ * memcpy_toio -	Copy a block of data into I/O memory
+ * @dst:		The (I/O memory) destination for the copy
+ * @src:		The (RAM) source for the data
+ * @count:		The number of bytes to copy
+ *
+ * Copy a block of data to I/O memory.
+ */
+void memcpy_toio(volatile void __iomem *dst, const void *src, size_t count);
+#endif
+
 #endif /* !__ASSEMBLY__ */
 #endif /* __ASM_GENERIC_IO_H__ */
diff --git a/lib/Makefile b/lib/Makefile
index a2e6066886495502a47bb1595217e8eb82374763..6e4f59141f3faca156b13e7f78c5d4312af20193 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -123,6 +123,7 @@ obj-y += ctype.o
 obj-y += div64.o
 obj-$(CONFIG_$(PHASE_)OF_LIBFDT) += fdtdec.o fdtdec_common.o
 obj-y += hang.o
+obj-y += iomem_copy.o
 obj-y += linux_compat.o
 obj-y += linux_string.o
 obj-$(CONFIG_$(PHASE_)LMB) += lmb.o
diff --git a/lib/iomem_copy.c b/lib/iomem_copy.c
new file mode 100644
index 0000000000000000000000000000000000000000..10661fe216f780b9ebb27828b2618d4306bb07e4
--- /dev/null
+++ b/lib/iomem_copy.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2024 Kalray, Inc.  All Rights Reserved.
+ */
+
+#include <linux/compat.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <asm-generic/unaligned.h>
+
+#ifndef memset_io
+/**
+ * memset_io() - Set a range of I/O memory to a constant value
+ * @addr: The beginning of the I/O-memory range to set
+ * @val: The value to set the memory to
+ * @count: The number of bytes to set
+ *
+ * Set a range of I/O memory to a given value.
+ */
+void memset_io(volatile void __iomem *addr, int val, size_t count)
+{
+	long qc = (u8)val;
+
+	qc *= ~0UL / 0xff;
+
+	while (count && !IS_ALIGNED((long)addr, sizeof(long))) {
+		__raw_writeb(val, addr);
+		addr++;
+		count--;
+	}
+
+	while (count >= sizeof(long)) {
+#ifdef CONFIG_64BIT
+		__raw_writeq(qc, addr);
+#else
+		__raw_writel(qc, addr);
+#endif
+
+		addr += sizeof(long);
+		count -= sizeof(long);
+	}
+
+	while (count) {
+		__raw_writeb(val, addr);
+		addr++;
+		count--;
+	}
+}
+EXPORT_SYMBOL(memset_io);
+#endif
+
+#ifndef memcpy_fromio
+/**
+ * memcpy_fromio() - Copy a block of data from I/O memory
+ * @dst: The (RAM) destination for the copy
+ * @src: The (I/O memory) source for the data
+ * @count: The number of bytes to copy
+ *
+ * Copy a block of data from I/O memory.
+ */
+void memcpy_fromio(void *dst, const volatile void __iomem *src, size_t count)
+{
+	while (count && !IS_ALIGNED((long)src, sizeof(long))) {
+		*(u8 *)dst = __raw_readb(src);
+		src++;
+		dst++;
+		count--;
+	}
+
+	while (count >= sizeof(long)) {
+#ifdef CONFIG_64BIT
+		long val = __raw_readq(src);
+#else
+		long val = __raw_readl(src);
+#endif
+		put_unaligned(val, (long *)dst);
+
+
+		src += sizeof(long);
+		dst += sizeof(long);
+		count -= sizeof(long);
+	}
+
+	while (count) {
+		*(u8 *)dst = __raw_readb(src);
+		src++;
+		dst++;
+		count--;
+	}
+}
+EXPORT_SYMBOL(memcpy_fromio);
+#endif
+
+#ifndef memcpy_toio
+/**
+ * memcpy_toio() -Copy a block of data into I/O memory
+ * @dst: The (I/O memory) destination for the copy
+ * @src: The (RAM) source for the data
+ * @count: The number of bytes to copy
+ *
+ * Copy a block of data to I/O memory.
+ */
+void memcpy_toio(volatile void __iomem *dst, const void *src, size_t count)
+{
+	while (count && !IS_ALIGNED((long)dst, sizeof(long))) {
+		__raw_writeb(*(u8 *)src, dst);
+		src++;
+		dst++;
+		count--;
+	}
+
+	while (count >= sizeof(long)) {
+		long val = get_unaligned((long *)src);
+#ifdef CONFIG_64BIT
+		__raw_writeq(val, dst);
+#else
+		__raw_writel(val, dst);
+#endif
+
+		src += sizeof(long);
+		dst += sizeof(long);
+		count -= sizeof(long);
+	}
+
+	while (count) {
+		__raw_writeb(*(u8 *)src, dst);
+		src++;
+		dst++;
+		count--;
+	}
+}
+EXPORT_SYMBOL(memcpy_toio);
+#endif
+
+

-- 
2.35.3