Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 1 | Copyright (c) 2016 Xilinx Inc. |
| 2 | |
| 3 | This work is licensed under the terms of the GNU GPL, version 2 or later. See |
| 4 | the COPYING file in the top-level directory. |
| 5 | |
| 6 | |
| 7 | The 'loader' device allows the user to load multiple images or values into |
| 8 | QEMU at startup. |
| 9 | |
| 10 | Loading Data into Memory Values |
Alistair Francis | bcf4827 | 2016-10-17 19:22:16 +0100 | [diff] [blame] | 11 | ------------------------------- |
Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 12 | The loader device allows memory values to be set from the command line. This |
| 13 | can be done by following the syntax below: |
| 14 | |
| 15 | -device loader,addr=<addr>,data=<data>,data-len=<data-len> |
| 16 | [,data-be=<data-be>][,cpu-num=<cpu-num>] |
| 17 | |
| 18 | <addr> - The address to store the data in. |
| 19 | <data> - The value to be written to the address. The maximum size of |
| 20 | the data is 8 bytes. |
| 21 | <data-len> - The length of the data in bytes. This argument must be |
| 22 | included if the data argument is. |
| 23 | <data-be> - Set to true if the data to be stored on the guest should be |
| 24 | written as big endian data. The default is to write little |
| 25 | endian data. |
| 26 | <cpu-num> - The number of the CPU's address space where the data should |
| 27 | be loaded. If not specified the address space of the first |
| 28 | CPU is used. |
| 29 | |
| 30 | All values are parsed using the standard QemuOps parsing. This allows the user |
| 31 | to specify any values in any format supported. By default the values |
| 32 | will be parsed as decimal. To use hex values the user should prefix the number |
| 33 | with a '0x'. |
| 34 | |
| 35 | An example of loading value 0x8000000e to address 0xfd1a0104 is: |
| 36 | -device loader,addr=0xfd1a0104,data=0x8000000e,data-len=4 |
| 37 | |
| 38 | Setting a CPU's Program Counter |
Alistair Francis | bcf4827 | 2016-10-17 19:22:16 +0100 | [diff] [blame] | 39 | ------------------------------- |
Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 40 | The loader device allows the CPU's PC to be set from the command line. This |
| 41 | can be done by following the syntax below: |
| 42 | |
| 43 | -device loader,addr=<addr>,cpu-num=<cpu-num> |
| 44 | |
| 45 | <addr> - The value to use as the CPU's PC. |
| 46 | <cpu-num> - The number of the CPU whose PC should be set to the |
| 47 | specified value. |
| 48 | |
| 49 | All values are parsed using the standard QemuOps parsing. This allows the user |
| 50 | to specify any values in any format supported. By default the values |
| 51 | will be parsed as decimal. To use hex values the user should prefix the number |
| 52 | with a '0x'. |
| 53 | |
| 54 | An example of setting CPU 0's PC to 0x8000 is: |
| 55 | -device loader,addr=0x8000,cpu-num=0 |
| 56 | |
| 57 | Loading Files |
Alistair Francis | bcf4827 | 2016-10-17 19:22:16 +0100 | [diff] [blame] | 58 | ------------- |
Stefan Hajnoczi | 67c791f | 2018-08-20 11:24:31 +0100 | [diff] [blame] | 59 | The loader device also allows files to be loaded into memory. It can load ELF, |
| 60 | U-Boot, and Intel HEX executable formats as well as raw images. The syntax is |
| 61 | shown below: |
Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 62 | |
| 63 | -device loader,file=<file>[,addr=<addr>][,cpu-num=<cpu-num>][,force-raw=<raw>] |
| 64 | |
| 65 | <file> - A file to be loaded into memory |
Stefan Hajnoczi | 67c791f | 2018-08-20 11:24:31 +0100 | [diff] [blame] | 66 | <addr> - The memory address where the file should be loaded. This is |
| 67 | required for raw images and ignored for non-raw files. |
Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 68 | <cpu-num> - This specifies the CPU that should be used. This is an |
| 69 | optional argument and will cause the CPU's PC to be set to |
Stefan Hajnoczi | 67c791f | 2018-08-20 11:24:31 +0100 | [diff] [blame] | 70 | the memory address where the raw file is loaded or the entry |
| 71 | point specified in the executable format header. This option |
| 72 | should only be used for the boot image. |
Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 73 | This will also cause the image to be written to the specified |
| 74 | CPU's address space. If not specified, the default is CPU 0. |
Alistair Francis | bcf4827 | 2016-10-17 19:22:16 +0100 | [diff] [blame] | 75 | <force-raw> - Setting force-raw=on forces the file to be treated as a raw |
Stefan Hajnoczi | 67c791f | 2018-08-20 11:24:31 +0100 | [diff] [blame] | 76 | image. This can be used to load supported executable formats |
| 77 | as if they were raw. |
Alistair Francis | 03bf195 | 2016-10-04 13:28:09 +0100 | [diff] [blame] | 78 | |
| 79 | All values are parsed using the standard QemuOps parsing. This allows the user |
| 80 | to specify any values in any format supported. By default the values |
| 81 | will be parsed as decimal. To use hex values the user should prefix the number |
| 82 | with a '0x'. |
| 83 | |
| 84 | An example of loading an ELF file which CPU0 will boot is shown below: |
| 85 | -device loader,file=./images/boot.elf,cpu-num=0 |
Alistair Francis | bcf4827 | 2016-10-17 19:22:16 +0100 | [diff] [blame] | 86 | |
| 87 | Restrictions and ToDos |
| 88 | ---------------------- |
| 89 | - At the moment it is just assumed that if you specify a cpu-num then you |
| 90 | want to set the PC as well. This might not always be the case. In future |
| 91 | the internal state 'set_pc' (which exists in the generic loader now) should |
| 92 | be exposed to the user so that they can choose if the PC is set or not. |