The helper provides a common FDT load mechanism to load the (optional compressed) DTB to the provided destination address in a user agnostic manner.
Early FDTs may be useful for other firmware binaries like TEEs (e.g. OP-TEE) which are loaded and started during the barebox boot phase. Signed-off-by: Marco Felsch <[email protected]> --- include/pbl.h | 2 ++ pbl/fdt.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 81 insertions(+) diff --git a/include/pbl.h b/include/pbl.h index 14a463ef8a9f18e42a3332889ca8d9b30d8f1ceb..514f1143706785946e4190f23f95422f23df42e3 100644 --- a/include/pbl.h +++ b/include/pbl.h @@ -31,6 +31,8 @@ fdt_device_get_match_data(const void *fdt, const char *nodepath, int pbl_barebox_verify(const void *compressed_start, unsigned int len, const void *hash, unsigned int hash_len); +int pbl_load_fdt(const void *fdt, void *dest, int destsize); + #endif void __noreturn barebox_pbl_entry(ulong, ulong, void *); diff --git a/pbl/fdt.c b/pbl/fdt.c index ac377446caeafb1beaeb211aa8bdec8767ae21fe..3c90959f8e73ea7310248f9b31359d6e8a86ae57 100644 --- a/pbl/fdt.c +++ b/pbl/fdt.c @@ -1,8 +1,10 @@ // SPDX-License-Identifier: GPL-2.0 +#include <compressed-dtb.h> #include <linux/libfdt.h> #include <pbl.h> #include <linux/printk.h> #include <stdio.h> +#include <uncompress.h> static const __be32 *fdt_parse_reg(const __be32 *reg, uint32_t n, uint64_t *val) @@ -185,3 +187,80 @@ const void *fdt_device_get_match_data(const void *fdt, const char *nodepath, return NULL; } + +static int pbl_open_dtbz_into(const void *fdt, void *buf, int bufsize) +{ + const struct barebox_boarddata_compressed_dtb *compressed_dtb; + int error; + + if (!fdt_blob_can_be_decompressed(fdt)) { + pr_warn("DTB can't be decompressed\n"); + return -EINVAL; + } + + compressed_dtb = fdt; + + if (IS_ENABLED(CONFIG_IMAGE_COMPRESSION_NONE)) { + error = fdt_open_into(compressed_dtb->data, buf, bufsize); + if (error) { + pr_warn("Failed to open uncompressed DTB with %s\n", + fdt_strerror(error)); + return -EINVAL; + } + return 0; + } + + if (bufsize < compressed_dtb->datalen_uncompressed) { + pr_warn("FDT buffer to small, min. %u bytes required\n", + compressed_dtb->datalen_uncompressed); + return -EINVAL; + } + + /* + * No error handling required, since this will hang() if uncompress + * fails. + */ + pbl_dtbz_uncompress(buf, (void *)compressed_dtb->data, + compressed_dtb->datalen); + + if (!blob_is_fdt(buf)) { + pr_warn("Failed to determine FDT type for uncompressed DTB\n"); + return -EINVAL; + } + + /* Required to setup size data structures to allow runtime adaptions */ + error = fdt_open_into(buf, buf, bufsize); + if (error) { + pr_warn("Failed to open decompressed DTB with %s\n", + fdt_strerror(error)); + return -EINVAL; + } + + return 0; +} + +int pbl_load_fdt(const void *fdt, void *dest, int destsize) +{ + if (destsize == 0 || !dest || !fdt) { + pr_warn("Skip early FDT load, invalid input\n"); + return -EINVAL; + } + + if (blob_is_fdt(fdt)) { + int error; + + error = fdt_open_into(fdt, dest, destsize); + if (error) { + pr_warn("Failed to uncompressed DTB with %s\n", + fdt_strerror(error)); + return -EINVAL; + } + return 0; + } else if (blob_is_compressed_fdt(fdt)) { + return pbl_open_dtbz_into(fdt, dest, destsize); + } + + pr_warn("FDT detection failed\n"); + + return -EINVAL; +} -- 2.47.3
