xref: /linux-6.15/include/linux/io.h (revision cd354f1a)
1 /*
2  * Copyright 2006 PathScale, Inc.  All Rights Reserved.
3  *
4  * This file is free software; you can redistribute it and/or modify
5  * it under the terms of version 2 of the GNU General Public License
6  * as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
16  */
17 
18 #ifndef _LINUX_IO_H
19 #define _LINUX_IO_H
20 
21 #include <linux/types.h>
22 #include <asm/io.h>
23 #include <asm/page.h>
24 
25 struct device;
26 
27 void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
28 void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
29 
30 int ioremap_page_range(unsigned long addr, unsigned long end,
31 		       unsigned long phys_addr, pgprot_t prot);
32 
33 /*
34  * Managed iomap interface
35  */
36 void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
37 			       unsigned int nr);
38 void devm_ioport_unmap(struct device *dev, void __iomem *addr);
39 
40 void __iomem * devm_ioremap(struct device *dev, unsigned long offset,
41 			    unsigned long size);
42 void __iomem * devm_ioremap_nocache(struct device *dev, unsigned long offset,
43 				    unsigned long size);
44 void devm_iounmap(struct device *dev, void __iomem *addr);
45 
46 /**
47  *	check_signature		-	find BIOS signatures
48  *	@io_addr: mmio address to check
49  *	@signature:  signature block
50  *	@length: length of signature
51  *
52  *	Perform a signature comparison with the mmio address io_addr. This
53  *	address should have been obtained by ioremap.
54  *	Returns 1 on a match.
55  */
56 
57 static inline int check_signature(const volatile void __iomem *io_addr,
58 	const unsigned char *signature, int length)
59 {
60 	int retval = 0;
61 	do {
62 		if (readb(io_addr) != *signature)
63 			goto out;
64 		io_addr++;
65 		signature++;
66 		length--;
67 	} while (length);
68 	retval = 1;
69 out:
70 	return retval;
71 }
72 
73 #endif /* _LINUX_IO_H */
74