root / target-ppc / kvm_ppc.c @ 91a75935
History | View | Annotate | Download (2.6 kB)
1 |
/*
|
---|---|
2 |
* PowerPC KVM support
|
3 |
*
|
4 |
* Copyright IBM Corp. 2008
|
5 |
*
|
6 |
* Authors:
|
7 |
* Hollis Blanchard <hollisb@us.ibm.com>
|
8 |
*
|
9 |
* This work is licensed under the terms of the GNU GPL, version 2 or later.
|
10 |
* See the COPYING file in the top-level directory.
|
11 |
*
|
12 |
*/
|
13 |
|
14 |
#include "qemu-common.h" |
15 |
#include "qemu-timer.h" |
16 |
#include "kvm_ppc.h" |
17 |
#include "device_tree.h" |
18 |
|
19 |
#define PROC_DEVTREE_PATH "/proc/device-tree" |
20 |
|
21 |
static QEMUTimer *kvmppc_timer;
|
22 |
static unsigned int kvmppc_timer_rate; |
23 |
|
24 |
#ifdef CONFIG_FDT
|
25 |
int kvmppc_read_host_property(const char *node_path, const char *prop, |
26 |
void *val, size_t len)
|
27 |
{ |
28 |
char *path;
|
29 |
FILE *f; |
30 |
int ret = 0; |
31 |
int pathlen;
|
32 |
|
33 |
pathlen = snprintf(NULL, 0, "%s/%s/%s", PROC_DEVTREE_PATH, node_path, prop) |
34 |
+ 1;
|
35 |
path = qemu_malloc(pathlen); |
36 |
|
37 |
snprintf(path, pathlen, "%s/%s/%s", PROC_DEVTREE_PATH, node_path, prop);
|
38 |
|
39 |
f = fopen(path, "rb");
|
40 |
if (f == NULL) { |
41 |
ret = errno; |
42 |
goto free;
|
43 |
} |
44 |
|
45 |
len = fread(val, len, 1, f);
|
46 |
if (len != 1) { |
47 |
ret = ferror(f); |
48 |
goto close;
|
49 |
} |
50 |
|
51 |
close:
|
52 |
fclose(f); |
53 |
free:
|
54 |
free(path); |
55 |
return ret;
|
56 |
} |
57 |
|
58 |
static int kvmppc_copy_host_cell(void *fdt, const char *node, const char *prop) |
59 |
{ |
60 |
uint32_t cell; |
61 |
int ret;
|
62 |
|
63 |
ret = kvmppc_read_host_property(node, prop, &cell, sizeof(cell));
|
64 |
if (ret < 0) { |
65 |
fprintf(stderr, "couldn't read host %s/%s\n", node, prop);
|
66 |
goto out;
|
67 |
} |
68 |
|
69 |
ret = qemu_devtree_setprop_cell(fdt, node, prop, cell); |
70 |
if (ret < 0) { |
71 |
fprintf(stderr, "couldn't set guest %s/%s\n", node, prop);
|
72 |
goto out;
|
73 |
} |
74 |
|
75 |
out:
|
76 |
return ret;
|
77 |
} |
78 |
|
79 |
void kvmppc_fdt_update(void *fdt) |
80 |
{ |
81 |
/* Copy data from the host device tree into the guest. Since the guest can
|
82 |
* directly access the timebase without host involvement, we must expose
|
83 |
* the correct frequencies. */
|
84 |
kvmppc_copy_host_cell(fdt, "/cpus/cpu@0", "clock-frequency"); |
85 |
kvmppc_copy_host_cell(fdt, "/cpus/cpu@0", "timebase-frequency"); |
86 |
} |
87 |
#endif
|
88 |
|
89 |
static void kvmppc_timer_hack(void *opaque) |
90 |
{ |
91 |
qemu_service_io(); |
92 |
qemu_mod_timer(kvmppc_timer, qemu_get_clock(vm_clock) + kvmppc_timer_rate); |
93 |
} |
94 |
|
95 |
void kvmppc_init(void) |
96 |
{ |
97 |
/* XXX The only reason KVM yields control back to qemu is device IO. Since
|
98 |
* an idle guest does no IO, qemu's device model will never get a chance to
|
99 |
* run. So, until Qemu gains IO threads, we create this timer to ensure
|
100 |
* that the device model gets a chance to run. */
|
101 |
kvmppc_timer_rate = get_ticks_per_sec() / 10;
|
102 |
kvmppc_timer = qemu_new_timer(vm_clock, &kvmppc_timer_hack, NULL);
|
103 |
qemu_mod_timer(kvmppc_timer, qemu_get_clock(vm_clock) + kvmppc_timer_rate); |
104 |
} |
105 |
|