From f2a9942fbc47491cc5f5151670c42d43dc0544cb Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Tue, 5 Jul 2016 10:26:46 +0200 Subject: tests: Introduce DT overlay tests This adds a bunch of unit tests for the "fdt apply" command. They've all been run successfully in the sandbox. However, as you still require an out-of-tree dtc with overlay support, this is disabled by default. Acked-by: Simon Glass Acked-by: Pantelis Antoniou Signed-off-by: Maxime Ripard --- lib/libfdt/fdt_overlay.c | 311 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 262 insertions(+), 49 deletions(-) (limited to 'lib') diff --git a/lib/libfdt/fdt_overlay.c b/lib/libfdt/fdt_overlay.c index 1dac8fd..40b6d27 100644 --- a/lib/libfdt/fdt_overlay.c +++ b/lib/libfdt/fdt_overlay.c @@ -5,6 +5,20 @@ #include "libfdt_internal.h" +/** + * overlay_get_target_phandle - retrieves the target phandle of a fragment + * @fdto: pointer to the device tree overlay blob + * @fragment: node offset of the fragment in the overlay + * + * overlay_get_target_phandle() retrieves the target phandle of an + * overlay fragment when that fragment uses a phandle (target + * property) instead of a path (target-path property). + * + * returns: + * the phandle pointed by the target property + * 0, if the phandle was not found + * -1, if the phandle was malformed + */ static uint32_t overlay_get_target_phandle(const void *fdto, int fragment) { const uint32_t *val; @@ -14,12 +28,26 @@ static uint32_t overlay_get_target_phandle(const void *fdto, int fragment) if (!val) return 0; - if ((*val == 0xffffffff) || (len != sizeof(*val))) - return 0xffffffff; + if ((*val == (uint32_t)-1) || (len != sizeof(*val))) + return (uint32_t)-1; return fdt32_to_cpu(*val); } +/** + * overlay_get_target - retrieves the target phandle of a fragment + * @fdt: Base device tree blob + * @fdto: Device tree overlay blob + * @fragment: node offset of the fragment in the overlay + * + * overlay_get_target() retrieves the target phandle in the base + * device tree of a fragment, no matter how the actual targetting is + * done (through a phandle or a path) + * + * returns: + * the targetted node offset in the base device tree + * Negative error code on error + */ static int overlay_get_target(const void *fdt, const void *fdto, int fragment) { @@ -28,7 +56,7 @@ static int overlay_get_target(const void *fdt, const void *fdto, /* Try first to do a phandle based lookup */ phandle = overlay_get_target_phandle(fdto, fragment); - if (phandle == -1) + if (phandle == (uint32_t)-1) return -FDT_ERR_BADPHANDLE; if (phandle) @@ -42,6 +70,20 @@ static int overlay_get_target(const void *fdt, const void *fdto, return fdt_path_offset(fdt, path); } +/** + * overlay_phandle_add_offset - Increases a phandle by an offset + * @fdt: Base device tree blob + * @node: Device tree overlay blob + * @name: Name of the property to modify (phandle or linux,phandle) + * @delta: offset to apply + * + * overlay_phandle_add_offset() increments a node phandle by a given + * offset. + * + * returns: + * 0 on success. + * Negative error code on error + */ static int overlay_phandle_add_offset(void *fdt, int node, const char *name, uint32_t delta) { @@ -64,6 +106,21 @@ static int overlay_phandle_add_offset(void *fdt, int node, return fdt_setprop_inplace_u32(fdt, node, name, adj_val); } +/** + * overlay_adjust_node_phandles - Offsets the phandles of a node + * @fdto: Device tree overlay blob + * @node: Offset of the node we want to adjust + * @delta: Offset to shift the phandles of + * + * overlay_adjust_node_phandles() adds a constant to all the phandles + * of a given node. This is mainly use as part of the overlay + * application process, when we want to update all the overlay + * phandles to not conflict with the overlays of the base device tree. + * + * returns: + * 0 on success + * Negative error code on failure + */ static int overlay_adjust_node_phandles(void *fdto, int node, uint32_t delta) { @@ -95,6 +152,20 @@ static int overlay_adjust_node_phandles(void *fdto, int node, return 0; } +/** + * overlay_adjust_local_phandles - Adjust the phandles of a whole overlay + * @fdto: Device tree overlay blob + * @delta: Offset to shift the phandles of + * + * overlay_adjust_local_phandles() adds a constant to all the + * phandles of an overlay. This is mainly use as part of the overlay + * application process, when we want to update all the overlay + * phandles to not conflict with the overlays of the base device tree. + * + * returns: + * 0 on success + * Negative error code on failure + */ static int overlay_adjust_local_phandles(void *fdto, uint32_t delta) { /* @@ -103,6 +174,25 @@ static int overlay_adjust_local_phandles(void *fdto, uint32_t delta) return overlay_adjust_node_phandles(fdto, 0, delta); } +/** + * overlay_update_local_node_references - Adjust the overlay references + * @fdto: Device tree overlay blob + * @tree_node: Node offset of the node to operate on + * @fixup_node: Node offset of the matching local fixups node + * @delta: Offset to shift the phandles of + * + * overlay_update_local_nodes_references() update the phandles + * pointing to a node within the device tree overlay by adding a + * constant delta. + * + * This is mainly used as part of a device tree application process, + * where you want the device tree overlays phandles to not conflict + * with the ones from the base device tree before merging them. + * + * returns: + * 0 on success + * Negative error code on failure + */ static int overlay_update_local_node_references(void *fdto, int tree_node, int fixup_node, @@ -113,41 +203,49 @@ static int overlay_update_local_node_references(void *fdto, int ret; fdt_for_each_property_offset(fixup_prop, fdto, fixup_node) { - const uint32_t *val = NULL; - uint32_t adj_val, index; + const unsigned char *fixup_val, *tree_val; const char *name; int fixup_len; int tree_len; + int i; - val = fdt_getprop_by_offset(fdto, fixup_prop, - &name, &fixup_len); - if (!val) + fixup_val = fdt_getprop_by_offset(fdto, fixup_prop, + &name, &fixup_len); + if (!fixup_val) return fixup_len; - index = fdt32_to_cpu(*val); - val = fdt_getprop(fdto, tree_node, name, &tree_len); - if (!val) + tree_val = fdt_getprop(fdto, tree_node, name, &tree_len); + if (!tree_val) return tree_len; - /* - * The index can be unaligned. - * - * Use a memcpy for the architectures that do not - * support unaligned accesses. - */ - memcpy(&adj_val, (unsigned char *)val + index, - sizeof(uint32_t)); - - adj_val = fdt32_to_cpu(adj_val); - adj_val += delta; - adj_val = cpu_to_fdt32(adj_val); - - ret = fdt_setprop_inplace_namelen_partial(fdto, tree_node, - name, strlen(name), - index, &adj_val, - sizeof(adj_val)); - if (ret) - return ret; + for (i = 0; i < fixup_len; i += sizeof(uint32_t)) { + uint32_t adj_val, index; + + index = *(uint32_t *)(fixup_val + i); + index = fdt32_to_cpu(index); + + /* + * phandles to fixup can be unaligned. + * + * Use a memcpy for the architectures that do + * not support unaligned accesses. + */ + memcpy(&adj_val, tree_val + index, sizeof(uint32_t)); + + adj_val = fdt32_to_cpu(adj_val); + adj_val += delta; + adj_val = cpu_to_fdt32(adj_val); + + ret = fdt_setprop_inplace_namelen_partial(fdto, + tree_node, + name, + strlen(name), + index, + &adj_val, + sizeof(adj_val)); + if (ret) + return ret; + } } fdt_for_each_subnode(fdto, fixup_child, fixup_node) { @@ -171,11 +269,28 @@ static int overlay_update_local_node_references(void *fdto, return 0; } -static int overlay_update_local_references(void *dto, uint32_t delta) +/** + * overlay_update_local_references - Adjust the overlay references + * @fdto: Device tree overlay blob + * @delta: Offset to shift the phandles of + * + * overlay_update_local_references() update all the phandles pointing + * to a node within the device tree overlay by adding a constant + * delta to not conflict with the base overlay. + * + * This is mainly used as part of a device tree application process, + * where you want the device tree overlays phandles to not conflict + * with the ones from the base device tree before merging them. + * + * returns: + * 0 on success + * Negative error code on failure + */ +static int overlay_update_local_references(void *fdto, uint32_t delta) { int fixups; - fixups = fdt_path_offset(dto, "/__local_fixups__"); + fixups = fdt_path_offset(fdto, "/__local_fixups__"); if (fixups < 0) { /* There's no local phandles to adjust, bail out */ if (fixups == -FDT_ERR_NOTFOUND) @@ -187,10 +302,33 @@ static int overlay_update_local_references(void *dto, uint32_t delta) /* * Update our local references from the root of the tree */ - return overlay_update_local_node_references(dto, 0, fixups, + return overlay_update_local_node_references(fdto, 0, fixups, delta); } +/** + * overlay_fixup_one_phandle - Set an overlay phandle to the base one + * @fdt: Base Device Tree blob + * @fdto: Device tree overlay blob + * @symbols_off: Node offset of the symbols node in the base device tree + * @path: Path to a node holding a phandle in the overlay + * @path_len: number of path characters to consider + * @name: Name of the property holding the phandle reference in the overlay + * @name_len: number of name characters to consider + * @index: Index in the overlay property where the phandle is stored + * @label: Label of the node referenced by the phandle + * + * overlay_fixup_one_phandle() resolves an overlay phandle pointing to + * a node in the base device tree. + * + * This is part of the device tree overlay application process, when + * you want all the phandles in the overlay to point to the actual + * base dt nodes. + * + * returns: + * 0 on success + * Negative error code on failure + */ static int overlay_fixup_one_phandle(void *fdt, void *fdto, int symbols_off, const char *path, uint32_t path_len, @@ -225,6 +363,25 @@ static int overlay_fixup_one_phandle(void *fdt, void *fdto, &phandle, sizeof(phandle)); }; +/** + * overlay_fixup_phandle - Set an overlay phandle to the base one + * @fdt: Base Device Tree blob + * @fdto: Device tree overlay blob + * @symbols_off: Node offset of the symbols node in the base device tree + * @property: Property offset in the overlay holding the list of fixups + * + * overlay_fixup_phandle() resolves all the overlay phandles pointed + * to in a __local_fixup__ property, and updates them to match the + * phandles in use in the base device tree. + * + * This is part of the device tree overlay application process, when + * you want all the phandles in the overlay to point to the actual + * base dt nodes. + * + * returns: + * 0 on success + * Negative error code on failure + */ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, int property) { @@ -275,57 +432,98 @@ static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, return 0; } -static int overlay_fixup_phandles(void *dt, void *dto) +/** + * overlay_fixup_phandles - Resolve the overlay phandles to the base + * device tree + * @fdt: Base Device Tree blob + * @fdto: Device tree overlay blob + * + * overlay_fixup_phandles() resolves all the overlay phandles pointing + * to nodes in the base device tree. + * + * This is one of the steps of the device tree overlay application + * process, when you want all the phandles in the overlay to point to + * the actual base dt nodes. + * + * returns: + * 0 on success + * Negative error code on failure + */ +static int overlay_fixup_phandles(void *fdt, void *fdto) { int fixups_off, symbols_off; int property; - symbols_off = fdt_path_offset(dt, "/__symbols__"); - fixups_off = fdt_path_offset(dto, "/__fixups__"); + symbols_off = fdt_path_offset(fdt, "/__symbols__"); + fixups_off = fdt_path_offset(fdto, "/__fixups__"); + + fdt_for_each_property_offset(property, fdto, fixups_off) { + int ret; - fdt_for_each_property_offset(property, dto, fixups_off) - overlay_fixup_phandle(dt, dto, symbols_off, property); + ret = overlay_fixup_phandle(fdt, fdto, symbols_off, property); + if (ret) + return ret; + } return 0; } -static int apply_overlay_node(void *dt, int target, - void *dto, int fragment) +/** + * overlay_apply_node - Merge an overlay fragment into the base device tree + * @fdt: Base Device Tree blob + * @target: Node offset in the base device tree to apply the fragment to + * @fdto: Device tree overlay blob + * @fragment: Node offset in the overlay holding the changes to merge + * + * overlay_apply_node() merges an overlay fragment into a target base + * device tree node pointed. + * + * This is part of the final step in the device tree overlay + * application process, when all the phandles have been adjusted and + * resolved and you just have to merge overlay into the base device + * tree. + * + * returns: + * 0 on success + * Negative error code on failure + */ +static int overlay_apply_node(void *fdt, int target, + void *fdto, int fragment) { int property; int node; - fdt_for_each_property_offset(property, dto, fragment) { + fdt_for_each_property_offset(property, fdto, fragment) { const char *name; const void *prop; int prop_len; int ret; - prop = fdt_getprop_by_offset(dto, property, &name, + prop = fdt_getprop_by_offset(fdto, property, &name, &prop_len); if (prop_len == -FDT_ERR_NOTFOUND) return -FDT_ERR_INTERNAL; if (prop_len < 0) return prop_len; - ret = fdt_setprop(dt, target, name, prop, prop_len); + ret = fdt_setprop(fdt, target, name, prop, prop_len); if (ret) return ret; } - fdt_for_each_subnode(dto, node, fragment) { - const char *name = fdt_get_name(dto, node, NULL); + fdt_for_each_subnode(fdto, node, fragment) { + const char *name = fdt_get_name(fdto, node, NULL); int nnode; int ret; - nnode = fdt_add_subnode(dt, target, name); + nnode = fdt_add_subnode(fdt, target, name); if (nnode == -FDT_ERR_EXISTS) - nnode = fdt_subnode_offset(dt, target, name); + nnode = fdt_subnode_offset(fdt, target, name); if (nnode < 0) return nnode; - ret = apply_overlay_node(dt, nnode, dto, node); + ret = overlay_apply_node(fdt, nnode, fdto, node); if (ret) return ret; } @@ -333,6 +531,21 @@ static int apply_overlay_node(void *dt, int target, return 0; } +/** + * overlay_merge - Merge an overlay into its base device tree + * @fdt: Base Device Tree blob + * @fdto: Device tree overlay blob + * + * overlay_merge() merges an overlay into its base device tree. + * + * This is the final step in the device tree overlay application + * process, when all the phandles have been adjusted and resolved and + * you just have to merge overlay into the base device tree. + * + * returns: + * 0 on success + * Negative error code on failure + */ static int overlay_merge(void *dt, void *dto) { int fragment; @@ -350,7 +563,7 @@ static int overlay_merge(void *dt, void *dto) if (overlay < 0) return overlay; - ret = apply_overlay_node(dt, target, dto, overlay); + ret = overlay_apply_node(dt, target, dto, overlay); if (ret) return ret; } -- cgit v1.1