The helper provides a common FDT load mechanism to load the (compressed) DTB to the provided destination address. Early FDTs may required by other BL3x binaries like BL31 (TF-A) and BL32 (OP-TEE).
Signed-off-by: Marco Felsch <[email protected]> --- arch/Kconfig | 3 +++ include/pbl.h | 2 ++ pbl/Kconfig | 11 +++++++++ pbl/fdt.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 91 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index 55618bf896c25f2afa2786706e27fce6ab4b3a39..edd574879b244d3843f1b5a06e1e25c5d4acbc8d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -62,6 +62,9 @@ config ARCH_DMA_DEFAULT_COHERENT config ARCH_HAS_DMA_WRITE_COMBINE bool +config ARCH_HAS_EARLY_FDT_SUPPORT + bool + config ARCH_HAS_ASAN_FIBER_API bool diff --git a/include/pbl.h b/include/pbl.h index 9db4652e833bf5e82fd42a1cae19e94c4f2f868f..bf0c9e2ba29428361cb16a572295e66f20acdd82 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/Kconfig b/pbl/Kconfig index cab9325d16e8625bcca10125b3281062abffedbc..ea2086f33ea405ecd7b00065eaf9874218152b3a 100644 --- a/pbl/Kconfig +++ b/pbl/Kconfig @@ -65,6 +65,17 @@ config PBL_VERIFY_PIGGY depends on ARM || MIPS || RISCV bool "Verify barebox proper hash before decompression" if COMPILE_TEST +config PBL_EARLY_FDT_LOAD + bool "Enable early FDT loading" + depends on ARCH_HAS_EARLY_FDT_SUPPORT + select LIBFDT + help + This enables the support to decompress and load the barebox builtin DTB + during the pbl (BL2) phase. + + This is useful for BL31 and BL32 firmwares which may use the DTB for + device configuration. + config PBL_CLOCKSOURCE bool diff --git a/pbl/fdt.c b/pbl/fdt.c index ac377446caeafb1beaeb211aa8bdec8767ae21fe..0cd9f5a0f11723e9f9b6848e8553da481b92f2be 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 +187,76 @@ 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 ret; + + 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)) { + ret = fdt_open_into(compressed_dtb->data, buf, bufsize); + if (ret) + pr_warn("Failed to open uncompressed DTB with %s\n", + fdt_strerror(ret)); + return ret ? -EINVAL : 0; + } + + if (bufsize < compressed_dtb->datalen_uncompressed) { + pr_warn("FDT buffer to small, min. %u bytes required\n", + compressed_dtb->datalen_uncompressed); + return -EINVAL; + } + + ret = pbl_dtbz_uncompress(buf, (void *)compressed_dtb->data, + compressed_dtb->datalen); + if (ret) { + pr_warn("Failed to uncompress DTB err=%d\n", ret); + return ret; + } + + 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 */ + ret = fdt_open_into(buf, buf, bufsize); + if (ret) + pr_warn("Failed to open decompressed DTB with %s\n", fdt_strerror(ret)); + + return ret ? -EINVAL : 0; +} + +int pbl_load_fdt(const void *fdt, void *dest, int destsize) +{ + int ret; + + if (!IS_ENABLED(CONFIG_PBL_EARLY_FDT_LOAD)) + return -ENOTSUPP; + + if (destsize == 0) { + pr_warn("Skip early FDT load due to dest buffer size of 0-bytes\n"); + return -EINVAL; + } + + if (blob_is_fdt(fdt)) { + ret = fdt_open_into(fdt, dest, destsize); + if (ret) + pr_warn("Failed to uncompressed DTB with %s\n", + fdt_strerror(ret)); + return ret ? -EINVAL : 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
