1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2022 Felix Palmen
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 #ifndef	_LINUXKPI_LINUX_IO_64_NONATOMIC_LO_HI_H_
28 #define	_LINUXKPI_LINUX_IO_64_NONATOMIC_LO_HI_H_
29 
30 #include <linux/io.h>
31 
32 static inline uint64_t
lo_hi_readq(const volatile void * addr)33 lo_hi_readq(const volatile void *addr)
34 {
35 	const volatile uint32_t *p = addr;
36 	uint32_t l, h;
37 
38 	__io_br();
39 	l = le32toh(__raw_readl(p));
40 	h = le32toh(__raw_readl(p + 1));
41 	__io_ar();
42 
43 	return (l + ((uint64_t)h << 32));
44 }
45 
46 static inline void
lo_hi_writeq(uint64_t v,volatile void * addr)47 lo_hi_writeq(uint64_t v, volatile void *addr)
48 {
49 	volatile uint32_t *p = addr;
50 
51 	__io_bw();
52 	__raw_writel(htole32(v), p);
53 	__raw_writel(htole32(v >> 32), p + 1);
54 	__io_aw();
55 }
56 
57 #ifndef readq
58 #define readq(addr)	lo_hi_readq(addr)
59 #endif
60 
61 #ifndef writeq
62 #define writeq(v, addr)	lo_hi_writeq(v, addr)
63 #endif
64 
65 #endif	/* _LINUXKPI_LINUX_IO_64_NONATOMIC_LO_HI_H_ */
66