mirror of
https://github.com/qemu/qemu.git
synced 2024-11-24 19:33:39 +08:00
bcf48274ba
This patch does three things: - It adds a list of restrictions and ToDos - It corrects the header --- lines to match the length of the header - It clarifies the force-raw option Signed-off-by: Alistair Francis <alistair.francis@xilinx.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-id: e75d1d285cf8f45037c41ebe1bc3f68120f09cb9.1475702918.git.alistair.francis@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
93 lines
4.2 KiB
Plaintext
93 lines
4.2 KiB
Plaintext
Copyright (c) 2016 Xilinx Inc.
|
|
|
|
This work is licensed under the terms of the GNU GPL, version 2 or later. See
|
|
the COPYING file in the top-level directory.
|
|
|
|
|
|
The 'loader' device allows the user to load multiple images or values into
|
|
QEMU at startup.
|
|
|
|
Loading Data into Memory Values
|
|
-------------------------------
|
|
The loader device allows memory values to be set from the command line. This
|
|
can be done by following the syntax below:
|
|
|
|
-device loader,addr=<addr>,data=<data>,data-len=<data-len>
|
|
[,data-be=<data-be>][,cpu-num=<cpu-num>]
|
|
|
|
<addr> - The address to store the data in.
|
|
<data> - The value to be written to the address. The maximum size of
|
|
the data is 8 bytes.
|
|
<data-len> - The length of the data in bytes. This argument must be
|
|
included if the data argument is.
|
|
<data-be> - Set to true if the data to be stored on the guest should be
|
|
written as big endian data. The default is to write little
|
|
endian data.
|
|
<cpu-num> - The number of the CPU's address space where the data should
|
|
be loaded. If not specified the address space of the first
|
|
CPU is used.
|
|
|
|
All values are parsed using the standard QemuOps parsing. This allows the user
|
|
to specify any values in any format supported. By default the values
|
|
will be parsed as decimal. To use hex values the user should prefix the number
|
|
with a '0x'.
|
|
|
|
An example of loading value 0x8000000e to address 0xfd1a0104 is:
|
|
-device loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
|
|
|
|
Setting a CPU's Program Counter
|
|
-------------------------------
|
|
The loader device allows the CPU's PC to be set from the command line. This
|
|
can be done by following the syntax below:
|
|
|
|
-device loader,addr=<addr>,cpu-num=<cpu-num>
|
|
|
|
<addr> - The value to use as the CPU's PC.
|
|
<cpu-num> - The number of the CPU whose PC should be set to the
|
|
specified value.
|
|
|
|
All values are parsed using the standard QemuOps parsing. This allows the user
|
|
to specify any values in any format supported. By default the values
|
|
will be parsed as decimal. To use hex values the user should prefix the number
|
|
with a '0x'.
|
|
|
|
An example of setting CPU 0's PC to 0x8000 is:
|
|
-device loader,addr=0x8000,cpu-num=0
|
|
|
|
Loading Files
|
|
-------------
|
|
The loader device also allows files to be loaded into memory. It can load raw
|
|
files and ELF executable files. Raw files are loaded verbatim. ELF executable
|
|
files are loaded by an ELF loader. The syntax is shown below:
|
|
|
|
-device loader,file=<file>[,addr=<addr>][,cpu-num=<cpu-num>][,force-raw=<raw>]
|
|
|
|
<file> - A file to be loaded into memory
|
|
<addr> - The addr in memory that the file should be loaded. This is
|
|
ignored if you are using an ELF (unless force-raw is true).
|
|
This is required if you aren't loading an ELF.
|
|
<cpu-num> - This specifies the CPU that should be used. This is an
|
|
optional argument and will cause the CPU's PC to be set to
|
|
where the image is stored or in the case of an ELF file to
|
|
the value in the header. This option should only be used
|
|
for the boot image.
|
|
This will also cause the image to be written to the specified
|
|
CPU's address space. If not specified, the default is CPU 0.
|
|
<force-raw> - Setting force-raw=on forces the file to be treated as a raw
|
|
image. This can be used to load ELF files as if they were raw.
|
|
|
|
All values are parsed using the standard QemuOps parsing. This allows the user
|
|
to specify any values in any format supported. By default the values
|
|
will be parsed as decimal. To use hex values the user should prefix the number
|
|
with a '0x'.
|
|
|
|
An example of loading an ELF file which CPU0 will boot is shown below:
|
|
-device loader,file=./images/boot.elf,cpu-num=0
|
|
|
|
Restrictions and ToDos
|
|
----------------------
|
|
- At the moment it is just assumed that if you specify a cpu-num then you
|
|
want to set the PC as well. This might not always be the case. In future
|
|
the internal state 'set_pc' (which exists in the generic loader now) should
|
|
be exposed to the user so that they can choose if the PC is set or not.
|