device_tree: Add qemu_devtree_setprop_sized_cells() utility functions

We already have a qemu_devtree_setprop_cells() which sets a dtb
property to an array of cells whose values are specified by varargs.
However for the fairly common case of setting a property to a list
of addresses or of address,size pairs the number of cells used by
each element in the list depends on the parent's #address-cells
and #size-cells properties. To make this easier we provide an analogous
qemu_devtree_setprop_sized_cells() macro which allows the number
of cells used by each element to be specified. This is implemented
using an underlying qemu_devtree_setprop_sized_cells_from_array()
function which takes the values and sizes as an array; this may
also be directly useful for cases where the cell contents are
constructed programmatically.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1373977512-28932-2-git-send-email-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2013-07-16 13:25:05 +01:00
parent 24943978cb
commit 97c38f8c27
2 changed files with 92 additions and 0 deletions

View File

@ -308,3 +308,36 @@ void qemu_devtree_dumpdtb(void *fdt, int size)
exit(g_file_set_contents(dumpdtb, fdt, size, NULL) ? 0 : 1); exit(g_file_set_contents(dumpdtb, fdt, size, NULL) ? 0 : 1);
} }
} }
int qemu_devtree_setprop_sized_cells_from_array(void *fdt,
const char *node_path,
const char *property,
int numvalues,
uint64_t *values)
{
uint32_t *propcells;
uint64_t value;
int cellnum, vnum, ncells;
uint32_t hival;
propcells = g_new0(uint32_t, numvalues * 2);
cellnum = 0;
for (vnum = 0; vnum < numvalues; vnum++) {
ncells = values[vnum * 2];
if (ncells != 1 && ncells != 2) {
return -1;
}
value = values[vnum * 2 + 1];
hival = cpu_to_be32(value >> 32);
if (ncells > 1) {
propcells[cellnum++] = hival;
} else if (hival != 0) {
return -1;
}
propcells[cellnum++] = cpu_to_be32(value);
}
return qemu_devtree_setprop(fdt, node_path, property, propcells,
cellnum * sizeof(uint32_t));
}

View File

@ -51,4 +51,63 @@ int qemu_devtree_add_subnode(void *fdt, const char *name);
void qemu_devtree_dumpdtb(void *fdt, int size); void qemu_devtree_dumpdtb(void *fdt, int size);
/**
* qemu_devtree_setprop_sized_cells_from_array:
* @fdt: device tree blob
* @node_path: node to set property on
* @property: property to set
* @numvalues: number of values
* @values: array of number-of-cells, value pairs
*
* Set the specified property on the specified node in the device tree
* to be an array of cells. The values of the cells are specified via
* the values list, which alternates between "number of cells used by
* this value" and "value".
* number-of-cells must be either 1 or 2 (other values will result in
* an error being returned). If a value is too large to fit in the
* number of cells specified for it, an error is returned.
*
* This function is useful because device tree nodes often have cell arrays
* which are either lists of addresses or lists of address,size tuples, but
* the number of cells used for each element vary depending on the
* #address-cells and #size-cells properties of their parent node.
* If you know all your cell elements are one cell wide you can use the
* simpler qemu_devtree_setprop_cells(). If you're not setting up the
* array programmatically, qemu_devtree_setprop_sized_cells may be more
* convenient.
*
* Return value: 0 on success, <0 on error.
*/
int qemu_devtree_setprop_sized_cells_from_array(void *fdt,
const char *node_path,
const char *property,
int numvalues,
uint64_t *values);
/**
* qemu_devtree_setprop_sized_cells:
* @fdt: device tree blob
* @node_path: node to set property on
* @property: property to set
* @...: list of number-of-cells, value pairs
*
* Set the specified property on the specified node in the device tree
* to be an array of cells. The values of the cells are specified via
* the variable arguments, which alternates between "number of cells
* used by this value" and "value".
*
* This is a convenience wrapper for the function
* qemu_devtree_setprop_sized_cells_from_array().
*
* Return value: 0 on success, <0 on error.
*/
#define qemu_devtree_setprop_sized_cells(fdt, node_path, property, ...) \
({ \
uint64_t qdt_tmp[] = { __VA_ARGS__ }; \
qemu_devtree_setprop_sized_cells_from_array(fdt, node_path, \
property, \
ARRAY_SIZE(qdt_tmp) / 2, \
qdt_tmp); \
})
#endif /* __DEVICE_TREE_H__ */ #endif /* __DEVICE_TREE_H__ */