From 62b1db33778611a3023d1e3a98e869b495edc9ca Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Tue, 26 Sep 2023 08:14:43 -0600 Subject: [PATCH] dm: core: Add a way to convert a devicetree to a dtb Add a way to flatten a devicetree into binary form. For livetree this involves generating the devicetree using fdt_property() and other calls. For flattree it simply involves providing the buffer containing the tree. Signed-off-by: Simon Glass --- drivers/core/ofnode.c | 18 +++++++ include/dm/ofnode.h | 13 +++++ include/of_live.h | 10 ++++ lib/of_live.c | 122 ++++++++++++++++++++++++++++++++++++++++++ test/dm/ofnode.c | 24 +++++++++ 5 files changed, 187 insertions(+) diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c index a5efedf6af..39ba480c8f 100644 --- a/drivers/core/ofnode.c +++ b/drivers/core/ofnode.c @@ -243,6 +243,24 @@ int oftree_new(oftree *treep) #endif /* OFNODE_MULTI_TREE */ +int oftree_to_fdt(oftree tree, struct abuf *buf) +{ + int ret; + + if (of_live_active()) { + ret = of_live_flatten(ofnode_to_np(oftree_root(tree)), buf); + if (ret) + return log_msg_ret("flt", ret); + } else { + void *fdt = oftree_lookup_fdt(tree); + + abuf_init(buf); + abuf_set(buf, fdt, fdt_totalsize(fdt)); + } + + return 0; +} + /** * ofnode_from_tree_offset() - get an ofnode from a tree offset (flat tree) * diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h index f1ee02cd83..a8605fb718 100644 --- a/include/dm/ofnode.h +++ b/include/dm/ofnode.h @@ -17,6 +17,7 @@ /* Enable checks to protect against invalid calls */ #undef OF_CHECKS +struct abuf; struct resource; #include @@ -136,6 +137,18 @@ static inline ofnode noffset_to_ofnode(ofnode other_node, int of_offset) */ int oftree_new(oftree *treep); +/** + * oftree_to_fdt() - Convert an oftree to a flat FDT + * + * @tree: tree to flatten (if livetree) or copy (if not) + * @buf: Returns inited buffer containing the newly created flat tree. Note + * that for flat tree the buffer is not allocated. In either case the caller + * must call abut_uninit() to free any memory used by @buf + * Return: 0 on success, -ENOMEM if out of memory, other -ve value for any other + * error + */ +int oftree_to_fdt(oftree tree, struct abuf *buf); + /** * ofnode_to_np() - convert an ofnode to a live DT node pointer * diff --git a/include/of_live.h b/include/of_live.h index 81cb9bd13e..67bd5f02c7 100644 --- a/include/of_live.h +++ b/include/of_live.h @@ -9,6 +9,7 @@ #ifndef _OF_LIVE_H #define _OF_LIVE_H +struct abuf; struct device_node; /** @@ -54,4 +55,13 @@ void of_live_free(struct device_node *root); */ int of_live_create_empty(struct device_node **rootp); +/** + * of_live_flatten() - Create an FDT from a hierarchical tree + * + * @root: Root node of tree to convert + * @buf: Buffer to return the tree (inited by this function) + * Return: 0 if OK, -ENOMEM if out of memory + */ +int of_live_flatten(const struct device_node *root, struct abuf *buf); + #endif diff --git a/lib/of_live.c b/lib/of_live.c index e4eee38554..812c488f60 100644 --- a/lib/of_live.c +++ b/lib/of_live.c @@ -8,13 +8,21 @@ * Copyright (c) 2017 Google, Inc */ +#define LOG_CATEGORY LOGC_DT + #include +#include #include #include #include #include #include #include +#include + +enum { + BUF_STEP = SZ_64K, +}; static void *unflatten_dt_alloc(void **mem, unsigned long size, unsigned long align) @@ -355,3 +363,117 @@ int of_live_create_empty(struct device_node **rootp) return 0; } + +static int check_space(int ret, struct abuf *buf) +{ + if (ret == -FDT_ERR_NOSPACE) { + if (!abuf_realloc_inc(buf, BUF_STEP)) + return log_msg_ret("spc", -ENOMEM); + ret = fdt_resize(abuf_data(buf), abuf_data(buf), + abuf_size(buf)); + if (ret) + return log_msg_ret("res", -EFAULT); + + return -EAGAIN; + } + + return 0; +} + +/** + * flatten_node() - Write out the node and its properties into a flat tree + */ +static int flatten_node(struct abuf *buf, const struct device_node *node) +{ + const struct device_node *np; + const struct property *pp; + int ret; + + ret = fdt_begin_node(abuf_data(buf), node->name); + ret = check_space(ret, buf); + if (ret == -EAGAIN) { + ret = fdt_begin_node(abuf_data(buf), node->name); + if (ret) { + log_debug("Internal error a %d\n", ret); + return -EFAULT; + } + } + if (ret) + return log_msg_ret("beg", ret); + + /* First write out the properties */ + for (pp = node->properties; !ret && pp; pp = pp->next) { + ret = fdt_property(abuf_data(buf), pp->name, pp->value, + pp->length); + ret = check_space(ret, buf); + if (ret == -EAGAIN) { + ret = fdt_property(abuf_data(buf), pp->name, pp->value, + pp->length); + } + } + + /* Next write out the subnodes */ + for (np = node->child; np; np = np->sibling) { + ret = flatten_node(buf, np); + if (ret) + return log_msg_ret("sub", ret); + } + + ret = fdt_end_node(abuf_data(buf)); + ret = check_space(ret, buf); + if (ret == -EAGAIN) { + ret = fdt_end_node(abuf_data(buf)); + if (ret) { + log_debug("Internal error b %d\n", ret); + return -EFAULT; + } + } + if (ret) + return log_msg_ret("end", ret); + + return 0; +} + +int of_live_flatten(const struct device_node *root, struct abuf *buf) +{ + int ret; + + abuf_init(buf); + if (!abuf_realloc(buf, BUF_STEP)) + return log_msg_ret("ini", -ENOMEM); + + ret = fdt_create(abuf_data(buf), abuf_size(buf)); + if (!ret) + ret = fdt_finish_reservemap(abuf_data(buf)); + if (ret) { + log_debug("Failed to start FDT (err=%d)\n", ret); + return log_msg_ret("sta", -EINVAL); + } + + ret = flatten_node(buf, root); + if (ret) + return log_msg_ret("flt", ret); + + ret = fdt_finish(abuf_data(buf)); + ret = check_space(ret, buf); + if (ret == -EAGAIN) { + ret = fdt_finish(abuf_data(buf)); + if (ret) { + log_debug("Internal error c %d\n", ret); + return -EFAULT; + } + } + if (ret) + return log_msg_ret("fin", ret); + + ret = fdt_pack(abuf_data(buf)); + if (ret) { + log_debug("Failed to pack (err=%d)\n", ret); + return log_msg_ret("pac", -EFAULT); + } + + if (!abuf_realloc(buf, fdt_totalsize(abuf_data(buf)))) + return log_msg_ret("abu", -EFAULT); + + return 0; +} diff --git a/test/dm/ofnode.c b/test/dm/ofnode.c index 845cded449..ceeb8e5779 100644 --- a/test/dm/ofnode.c +++ b/test/dm/ofnode.c @@ -17,6 +17,7 @@ */ #include +#include #include #include #include @@ -26,6 +27,7 @@ #include #include #include +#include #include #include @@ -1456,3 +1458,25 @@ static int dm_test_ofnode_delete(struct unit_test_state *uts) return 0; } DM_TEST(dm_test_ofnode_delete, UT_TESTF_SCAN_FDT); + +static int dm_test_oftree_to_fdt(struct unit_test_state *uts) +{ + oftree tree, check; + struct abuf buf, buf2; + + tree = oftree_default(); + ut_assertok(oftree_to_fdt(tree, &buf)); + ut_assert(abuf_size(&buf) > SZ_16K); + + /* convert it back to a tree and see if it looks OK */ + check = oftree_from_fdt(abuf_data(&buf)); + ut_assert(oftree_valid(check)); + + ut_assertok(oftree_to_fdt(check, &buf2)); + ut_assert(abuf_size(&buf2) > SZ_16K); + ut_asserteq(abuf_size(&buf), abuf_size(&buf2)); + ut_asserteq_mem(abuf_data(&buf), abuf_data(&buf2), abuf_size(&buf)); + + return 0; +} +DM_TEST(dm_test_oftree_to_fdt, UT_TESTF_SCAN_FDT); -- 2.39.5