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.mayd...@linaro.org>
---
device_tree.c | 31 +++++++++++++++++++++
include/sysemu/device_tree.h | 62 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 93 insertions(+)
diff --git a/device_tree.c b/device_tree.c
index 10cf3d0..308205c 100644
--- a/device_tree.c
+++ b/device_tree.c
@@ -308,3 +308,34 @@ void qemu_devtree_dumpdtb(void *fdt, int size)
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];
+ assert(ncells == 1 || ncells == 2);
+ value = values[vnum * 2 + 1];
+ hival = cpu_to_be32(value >> 32);
+ if (ncells > 1) {
+ propcells[cellnum++] = hival;
+ } else if (hival != 0) {
+ return vnum + 1;
+ }
+ propcells[cellnum++] = cpu_to_be32(value);
+ }
+
+ return qemu_devtree_setprop(fdt, node_path, property, propcells,
+ cellnum * sizeof(uint32_t));
+}
diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h
index f0b3f35..8189ebc 100644
--- a/include/sysemu/device_tree.h
+++ b/include/sysemu/device_tree.h
@@ -51,4 +51,66 @@ int qemu_devtree_add_subnode(void *fdt, const char *name);
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 assert()).
+ *
+ * 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 if setting the property failed,
+ * n (for n>0) if value n wouldn't fit in the required number of cells.
+ * (This slightly odd convention is for the benefit of callers who might
+ * wish to print different error messages depending on which value
+ * was too large to fit, since values might be user-specified.)
+ */
+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 if setting the property failed,
+ * n (for n>0) if value n wouldn't fit in the required number of cells.
+ */
+#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__ */
--
1.7.9.5
