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2 Copyright (c) 2016, Xilinx Inc.
3
4 This work is licensed under the terms of the GNU GPL, version 2 or later. See
5 the COPYING file in the top-level directory.
6
7 Generic Loader
8 --------------
9
10 The 'loader' device allows the user to load multiple images or values into
11 QEMU at startup.
12
13 Loading Data into Memory Values
14 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
15 The loader device allows memory values to be set from the command line. This
16 can be done by following the syntax below::
17
18 -device loader,addr=<addr>,data=<data>,data-len=<data-len> \
19 [,data-be=<data-be>][,cpu-num=<cpu-num>]
20
21 ``<addr>``
22 The address to store the data in.
23
24 Note that as usual with QEMU numeric option values, the default is to
25 treat the argument as decimal. To specify a value in hex, prefix it
26 with '0x'.
27
28 ``<data>``
29 The value to be written to the address. The maximum size of the data
30 is 8 bytes.
31
32 ``<data-len>``
33 The length of the data in bytes. This argument must be included if
34 the data argument is.
35
36 ``<data-be>``
37 Set to true if the data to be stored on the guest should be written
38 as big endian data. The default is to write little endian data.
39
40 ``<cpu-num>``
41 The number of the CPU's address space where the data should be
42 loaded. If not specified the address space of the first CPU is used.
43
44
45 An example of loading value 0x8000000e to address 0xfd1a0104 is::
46
47 -device loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
48
49 Setting a CPU's Program Counter
50 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
51
52 The loader device allows the CPU's PC to be set from the command line. This
53 can be done by following the syntax below::
54
55 -device loader,addr=<addr>,cpu-num=<cpu-num>
56
57 ``<addr>``
58 The value to use as the CPU's PC.
59
60 Note that as usual with QEMU numeric option values, the default is to
61 treat the argument as decimal. To specify a value in hex, prefix it
62 with '0x'.
63
64 ``<cpu-num>``
65 The number of the CPU whose PC should be set to the specified value.
66
67 An example of setting CPU 0's PC to 0x8000 is::
68
69 -device loader,addr=0x8000,cpu-num=0
70
71 Loading Files
72 ^^^^^^^^^^^^^
73
74 The loader device also allows files to be loaded into memory. It can load ELF,
75 U-Boot, and Intel HEX executable formats as well as raw images. The syntax is
76 shown below:
77
78 -device loader,file=<file>[,addr=<addr>][,cpu-num=<cpu-num>][,force-raw=<raw>]
79
80 ``<file>``
81 A file to be loaded into memory
82
83 ``<addr>``
84 The memory address where the file should be loaded. This is required
85 for raw images and ignored for non-raw files.
86
87 Note that as usual with QEMU numeric option values, the default is to
88 treat the argument as decimal. To specify a value in hex, prefix it
89 with '0x'.
90
91 ``<cpu-num>``
92 This specifies the CPU that should be used. This is an
93 optional argument with two effects:
94
95 * this CPU's address space is used to load the data
96 * this CPU's PC will be set to the address where the raw file is loaded
97 or the entry point specified in the executable format header
98
99 If this option is not specified, then the data will be loaded via
100 the address space of the first CPU, and no CPU will have its PC set.
101
102 Note that there is currently no way to specify the address space to
103 load the data without also causing that CPU's PC to be set.
104
105 Since it sets the starting PC, this option should only be used for the boot
106 image.
107
108 ``<force-raw>``
109 Setting 'force-raw=on' forces the file to be treated as a raw image.
110 This can be used to load supported executable formats as if they
111 were raw.
112
113
114 An example of loading an ELF file which CPU0 will boot is shown below::
115
116 -device loader,file=./images/boot.elf,cpu-num=0