xref: /freebsd/sys/arm64/arm64/mem.c (revision 473c90ac04cec0abbb414978c53e9c259c9129e8)
1 /*-
2  * Copyright (c) 2014 Andrew Turner
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/conf.h>
31 #include <sys/malloc.h>
32 #include <sys/memrange.h>
33 #include <sys/uio.h>
34 
35 #include <machine/memdev.h>
36 #include <machine/vmparam.h>
37 
38 #include <vm/vm.h>
39 #include <vm/pmap.h>
40 #include <vm/vm_extern.h>
41 #include <vm/vm_page.h>
42 
43 struct mem_range_softc mem_range_softc;
44 
45 int
memrw(struct cdev * dev,struct uio * uio,int flags)46 memrw(struct cdev *dev, struct uio *uio, int flags)
47 {
48 	struct iovec *iov;
49 	struct vm_page m;
50 	vm_page_t marr;
51 	vm_offset_t off, v;
52 	vm_prot_t prot;
53 	u_int cnt;
54 	int error;
55 
56 	error = 0;
57 
58 	while (uio->uio_resid > 0 && error == 0) {
59 		iov = uio->uio_iov;
60 		if (iov->iov_len == 0) {
61 			uio->uio_iov++;
62 			uio->uio_iovcnt--;
63 			if (uio->uio_iovcnt < 0)
64 				panic("memrw");
65 			continue;
66 		}
67 
68 		v = uio->uio_offset;
69 		off = v & PAGE_MASK;
70 		cnt = ulmin(iov->iov_len, PAGE_SIZE - (u_int)off);
71 		if (cnt == 0)
72 			continue;
73 
74 		switch(dev2unit(dev)) {
75 		case CDEV_MINOR_KMEM:
76 			/* If the address is in the DMAP just copy it */
77 			if (VIRT_IN_DMAP(v)) {
78 				error = uiomove((void *)v, cnt, uio);
79 				break;
80 			}
81 
82 			switch (uio->uio_rw) {
83 			case UIO_READ:
84 				prot = VM_PROT_READ;
85 				break;
86 			case UIO_WRITE:
87 				prot = VM_PROT_WRITE;
88 				break;
89 			}
90 
91 			if (!kernacc((void *)v, cnt, prot)) {
92 				error = EFAULT;
93 				break;
94 			}
95 
96 			/* Get the physical address to read */
97 			v = pmap_extract(kernel_pmap, v);
98 			if (v == 0) {
99 				error = EFAULT;
100 				break;
101 			}
102 
103 			/* FALLTHROUGH */
104 		case CDEV_MINOR_MEM:
105 			/* If within the DMAP use this to copy from */
106 			if (PHYS_IN_DMAP(v)) {
107 				v = PHYS_TO_DMAP(v);
108 				error = uiomove((void *)v, cnt, uio);
109 				break;
110 			}
111 
112 			/* Have uiomove_fromphys handle the data */
113 			m.phys_addr = trunc_page(v);
114 			marr = &m;
115 			uiomove_fromphys(&marr, off, cnt, uio);
116 			break;
117 		}
118 	}
119 
120 	return (error);
121 }
122 
123 /*
124  * allow user processes to MMAP some memory sections
125  * instead of going through read/write
126  */
127 /* ARGSUSED */
128 int
memmmap(struct cdev * dev,vm_ooffset_t offset,vm_paddr_t * paddr,int prot __unused,vm_memattr_t * memattr __unused)129 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
130     int prot __unused, vm_memattr_t *memattr __unused)
131 {
132 	if (dev2unit(dev) == CDEV_MINOR_MEM) {
133 		*paddr = offset;
134 		return (0);
135 	}
136 	return (-1);
137 }
138 
139 int
memioctl_md(struct cdev * dev __unused,u_long cmd __unused,caddr_t data __unused,int flags __unused,struct thread * td __unused)140 memioctl_md(struct cdev *dev __unused, u_long cmd __unused,
141     caddr_t data __unused, int flags __unused, struct thread *td __unused)
142 {
143 	return (ENOTTY);
144 }
145