device_tree: Add support for reading device tree properties

Add support for reading device tree properties (both generic
and single-cell ones) to QEMU's convenience wrapper layer.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com>
This commit is contained in:
Peter Maydell 2012-07-20 13:34:50 +01:00
parent 3871481c0a
commit f0aa713f65
2 changed files with 34 additions and 0 deletions

View File

@ -178,6 +178,36 @@ int qemu_devtree_setprop_string(void *fdt, const char *node_path,
return r;
}
const void *qemu_devtree_getprop(void *fdt, const char *node_path,
const char *property, int *lenp)
{
int len;
const void *r;
if (!lenp) {
lenp = &len;
}
r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp);
if (!r) {
fprintf(stderr, "%s: Couldn't get %s/%s: %s\n", __func__,
node_path, property, fdt_strerror(*lenp));
exit(1);
}
return r;
}
uint32_t qemu_devtree_getprop_cell(void *fdt, const char *node_path,
const char *property)
{
int len;
const uint32_t *p = qemu_devtree_getprop(fdt, node_path, property, &len);
if (len != 4) {
fprintf(stderr, "%s: %s/%s not 4 bytes long (not a cell?)\n",
__func__, node_path, property);
exit(1);
}
return be32_to_cpu(*p);
}
uint32_t qemu_devtree_get_phandle(void *fdt, const char *path)
{
uint32_t r;

View File

@ -28,6 +28,10 @@ int qemu_devtree_setprop_string(void *fdt, const char *node_path,
int qemu_devtree_setprop_phandle(void *fdt, const char *node_path,
const char *property,
const char *target_node_path);
const void *qemu_devtree_getprop(void *fdt, const char *node_path,
const char *property, int *lenp);
uint32_t qemu_devtree_getprop_cell(void *fdt, const char *node_path,
const char *property);
uint32_t qemu_devtree_get_phandle(void *fdt, const char *path);
uint32_t qemu_devtree_alloc_phandle(void *fdt);
int qemu_devtree_nop_node(void *fdt, const char *node_path);