From 57b98efa16cd660ef3a964979dbb15fd5b21a0b6 Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Fri, 18 Feb 2022 19:33:09 +0100 Subject: doc: describe fatload command Man-page for fatload command. Signed-off-by: Heinrich Schuchardt --- doc/usage/fatload.rst | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++ doc/usage/index.rst | 1 + 2 files changed, 81 insertions(+) create mode 100644 doc/usage/fatload.rst (limited to 'doc') diff --git a/doc/usage/fatload.rst b/doc/usage/fatload.rst new file mode 100644 index 00000000000..93acb27a536 --- /dev/null +++ b/doc/usage/fatload.rst @@ -0,0 +1,80 @@ +.. SPDX-License-Identifier: GPL-2.0+: + +fatload command +=============== + +Synopsis +-------- + +:: + + fatload [ [ [ [bytes [pos]]]]] + +Description +----------- + +The fatload command is used to read a file from a FAT filesystem into memory. +You can always use the :doc:`load command ` instead. + +The number of transferred bytes is saved in the environment variable filesize. +The load address is saved in the environment variable fileaddr. + +interface + interface for accessing the block device (mmc, sata, scsi, usb, ....) + +dev + device number + +part + partition number, defaults to 0 (whole device) + +addr + load address, defaults to environment variable loadaddr or if loadaddr is + not set to configuration variable CONFIG_SYS_LOAD_ADDR + +filename + path to file, defaults to environment variable bootfile + +bytes + maximum number of bytes to load + +pos + number of bytes to skip + +addr, bytes, pos are hexadecimal numbers. + +If either 'pos' or 'bytes' are not aligned according to the minimum alignment +requirement for DMA transfer (ARCH_DMA_MINALIGN) additional buffering will be +used, a misaligned buffer warning will be printed, and performance will suffer +for the load. + +Example +------- + +:: + + => fatload mmc 0:1 ${kernel_addr_r} snp.efi + 149280 bytes read in 11 ms (12.9 MiB/s) + => + => fatload mmc 0:1 ${kernel_addr_r} snp.efi 1000000 + 149280 bytes read in 9 ms (15.8 MiB/s) + => + => fatload mmc 0:1 ${kernel_addr_r} snp.efi 1000000 100 + 149024 bytes read in 10 ms (14.2 MiB/s) + => + => fatload mmc 0:1 ${kernel_addr_r} snp.efi 10 + 16 bytes read in 1 ms (15.6 KiB/s) + => + +Configuration +------------- + +The fatload command is only available if CONFIG_CMD_FAT=y. + +Return value +------------ + +The return value $? is set to 0 (true) if the file was successfully loaded +even if the number of bytes is less then the specified length. + +If an error occurs, the return value $? is set to 1 (false). diff --git a/doc/usage/index.rst b/doc/usage/index.rst index 964d761e13e..0aacf531b22 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -34,6 +34,7 @@ Shell commands exit false fatinfo + fatload for load loady -- cgit v1.2.3