diff options
Diffstat (limited to 'drivers/of/overlay.c')
| -rw-r--r-- | drivers/of/overlay.c | 112 |
1 files changed, 74 insertions, 38 deletions
diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index 7613f7d680c7..6fd8e6145e10 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -24,6 +24,26 @@ #include "of_private.h" /** + * struct target - info about current target node as recursing through overlay + * @np: node where current level of overlay will be applied + * @in_livetree: @np is a node in the live devicetree + * + * Used in the algorithm to create the portion of a changeset that describes + * an overlay fragment, which is a devicetree subtree. Initially @np is a node + * in the live devicetree where the overlay subtree is targeted to be grafted + * into. When recursing to the next level of the overlay subtree, the target + * also recurses to the next level of the live devicetree, as long as overlay + * subtree node also exists in the live devicetree. When a node in the overlay + * subtree does not exist at the same level in the live devicetree, target->np + * points to a newly allocated node, and all subsequent targets in the subtree + * will be newly allocated nodes. + */ +struct target { + struct device_node *np; + bool in_livetree; +}; + +/** * struct fragment - info about fragment nodes in overlay expanded device tree * @target: target of the overlay operation * @overlay: pointer to the __overlay__ node @@ -72,8 +92,7 @@ static int devicetree_corrupt(void) } static int build_changeset_next_level(struct overlay_changeset *ovcs, - struct device_node *target_node, - const struct device_node *overlay_node); + struct target *target, const struct device_node *overlay_node); /* * of_resolve_phandles() finds the largest phandle in the live tree. @@ -257,14 +276,17 @@ err_free_target_path: /** * add_changeset_property() - add @overlay_prop to overlay changeset * @ovcs: overlay changeset - * @target_node: where to place @overlay_prop in live tree + * @target: where @overlay_prop will be placed * @overlay_prop: property to add or update, from overlay tree * @is_symbols_prop: 1 if @overlay_prop is from node "/__symbols__" * - * If @overlay_prop does not already exist in @target_node, add changeset entry - * to add @overlay_prop in @target_node, else add changeset entry to update + * If @overlay_prop does not already exist in live devicetree, add changeset + * entry to add @overlay_prop in @target, else add changeset entry to update * value of @overlay_prop. * + * @target may be either in the live devicetree or in a new subtree that + * is contained in the changeset. + * * Some special properties are not updated (no error returned). * * Update of property in symbols node is not allowed. @@ -273,20 +295,22 @@ err_free_target_path: * invalid @overlay. */ static int add_changeset_property(struct overlay_changeset *ovcs, - struct device_node *target_node, - struct property *overlay_prop, + struct target *target, struct property *overlay_prop, bool is_symbols_prop) { struct property *new_prop = NULL, *prop; int ret = 0; - prop = of_find_property(target_node, overlay_prop->name, NULL); - if (!of_prop_cmp(overlay_prop->name, "name") || !of_prop_cmp(overlay_prop->name, "phandle") || !of_prop_cmp(overlay_prop->name, "linux,phandle")) return 0; + if (target->in_livetree) + prop = of_find_property(target->np, overlay_prop->name, NULL); + else + prop = NULL; + if (is_symbols_prop) { if (prop) return -EINVAL; @@ -299,10 +323,10 @@ static int add_changeset_property(struct overlay_changeset *ovcs, return -ENOMEM; if (!prop) - ret = of_changeset_add_property(&ovcs->cset, target_node, + ret = of_changeset_add_property(&ovcs->cset, target->np, new_prop); else - ret = of_changeset_update_property(&ovcs->cset, target_node, + ret = of_changeset_update_property(&ovcs->cset, target->np, new_prop); if (ret) { @@ -315,14 +339,14 @@ static int add_changeset_property(struct overlay_changeset *ovcs, /** * add_changeset_node() - add @node (and children) to overlay changeset - * @ovcs: overlay changeset - * @target_node: where to place @node in live tree - * @node: node from within overlay device tree fragment + * @ovcs: overlay changeset + * @target: where @node will be placed in live tree or changeset + * @node: node from within overlay device tree fragment * - * If @node does not already exist in @target_node, add changeset entry - * to add @node in @target_node. + * If @node does not already exist in @target, add changeset entry + * to add @node in @target. * - * If @node already exists in @target_node, and the existing node has + * If @node already exists in @target, and the existing node has * a phandle, the overlay node is not allowed to have a phandle. * * If @node has child nodes, add the children recursively via @@ -355,15 +379,16 @@ static int add_changeset_property(struct overlay_changeset *ovcs, * invalid @overlay. */ static int add_changeset_node(struct overlay_changeset *ovcs, - struct device_node *target_node, struct device_node *node) + struct target *target, struct device_node *node) { const char *node_kbasename; struct device_node *tchild; + struct target target_child; int ret = 0; node_kbasename = kbasename(node->full_name); - for_each_child_of_node(target_node, tchild) + for_each_child_of_node(target->np, tchild) if (!of_node_cmp(node_kbasename, kbasename(tchild->full_name))) break; @@ -372,22 +397,28 @@ static int add_changeset_node(struct overlay_changeset *ovcs, if (!tchild) return -ENOMEM; - tchild->parent = target_node; + tchild->parent = target->np; of_node_set_flag(tchild, OF_OVERLAY); ret = of_changeset_attach_node(&ovcs->cset, tchild); if (ret) return ret; - ret = build_changeset_next_level(ovcs, tchild, node); + target_child.np = tchild; + target_child.in_livetree = false; + + ret = build_changeset_next_level(ovcs, &target_child, node); of_node_put(tchild); return ret; } - if (node->phandle && tchild->phandle) + if (node->phandle && tchild->phandle) { ret = -EINVAL; - else - ret = build_changeset_next_level(ovcs, tchild, node); + } else { + target_child.np = tchild; + target_child.in_livetree = target->in_livetree; + ret = build_changeset_next_level(ovcs, &target_child, node); + } of_node_put(tchild); return ret; @@ -396,7 +427,7 @@ static int add_changeset_node(struct overlay_changeset *ovcs, /** * build_changeset_next_level() - add level of overlay changeset * @ovcs: overlay changeset - * @target_node: where to place @overlay_node in live tree + * @target: where to place @overlay_node in live tree * @overlay_node: node from within an overlay device tree fragment * * Add the properties (if any) and nodes (if any) from @overlay_node to the @@ -409,27 +440,26 @@ static int add_changeset_node(struct overlay_changeset *ovcs, * invalid @overlay_node. */ static int build_changeset_next_level(struct overlay_changeset *ovcs, - struct device_node *target_node, - const struct device_node *overlay_node) + struct target *target, const struct device_node *overlay_node) { struct device_node *child; struct property *prop; int ret; for_each_property_of_node(overlay_node, prop) { - ret = add_changeset_property(ovcs, target_node, prop, 0); + ret = add_changeset_property(ovcs, target, prop, 0); if (ret) { pr_debug("Failed to apply prop @%pOF/%s, err=%d\n", - target_node, prop->name, ret); + target->np, prop->name, ret); return ret; } } for_each_child_of_node(overlay_node, child) { - ret = add_changeset_node(ovcs, target_node, child); + ret = add_changeset_node(ovcs, target, child); if (ret) { pr_debug("Failed to apply node @%pOF/%pOFn, err=%d\n", - target_node, child, ret); + target->np, child, ret); of_node_put(child); return ret; } @@ -442,17 +472,17 @@ static int build_changeset_next_level(struct overlay_changeset *ovcs, * Add the properties from __overlay__ node to the @ovcs->cset changeset. */ static int build_changeset_symbols_node(struct overlay_changeset *ovcs, - struct device_node *target_node, + struct target *target, const struct device_node *overlay_symbols_node) { struct property *prop; int ret; for_each_property_of_node(overlay_symbols_node, prop) { - ret = add_changeset_property(ovcs, target_node, prop, 1); + ret = add_changeset_property(ovcs, target, prop, 1); if (ret) { pr_debug("Failed to apply prop @%pOF/%s, err=%d\n", - target_node, prop->name, ret); + target->np, prop->name, ret); return ret; } } @@ -475,6 +505,7 @@ static int build_changeset_symbols_node(struct overlay_changeset *ovcs, static int build_changeset(struct overlay_changeset *ovcs) { struct fragment *fragment; + struct target target; int fragments_count, i, ret; /* @@ -489,7 +520,9 @@ static int build_changeset(struct overlay_changeset *ovcs) for (i = 0; i < fragments_count; i++) { fragment = &ovcs->fragments[i]; - ret = build_changeset_next_level(ovcs, fragment->target, + target.np = fragment->target; + target.in_livetree = true; + ret = build_changeset_next_level(ovcs, &target, fragment->overlay); if (ret) { pr_debug("apply failed '%pOF'\n", fragment->target); @@ -499,7 +532,10 @@ static int build_changeset(struct overlay_changeset *ovcs) if (ovcs->symbols_fragment) { fragment = &ovcs->fragments[ovcs->count - 1]; - ret = build_changeset_symbols_node(ovcs, fragment->target, + + target.np = fragment->target; + target.in_livetree = true; + ret = build_changeset_symbols_node(ovcs, &target, fragment->overlay); if (ret) { pr_debug("apply failed '%pOF'\n", fragment->target); @@ -517,7 +553,7 @@ static int build_changeset(struct overlay_changeset *ovcs) * 1) "target" property containing the phandle of the target * 2) "target-path" property containing the path of the target */ -static struct device_node *find_target_node(struct device_node *info_node) +static struct device_node *find_target(struct device_node *info_node) { struct device_node *node; const char *path; @@ -623,7 +659,7 @@ static int init_overlay_changeset(struct overlay_changeset *ovcs, fragment = &fragments[cnt]; fragment->overlay = overlay_node; - fragment->target = find_target_node(node); + fragment->target = find_target(node); if (!fragment->target) { of_node_put(fragment->overlay); ret = -EINVAL; |