xref: /openbmc/qemu/docs/system/arm/mps2.rst (revision cba42d61)
1Arm MPS2 and MPS3 boards (``mps2-an385``, ``mps2-an386``, ``mps2-an500``, ``mps2-an505``, ``mps2-an511``, ``mps2-an521``, ``mps3-an524``)
2=========================================================================================================================================
3
4These board models all use Arm M-profile CPUs.
5
6The Arm MPS2, MPS2+ and MPS3 dev boards are FPGA based (the 2+ has a
7bigger FPGA but is otherwise the same as the 2; the 3 has a bigger
8FPGA again, can handle 4GB of RAM and has a USB controller and QSPI flash).
9
10Since the CPU itself and most of the devices are in the FPGA, the
11details of the board as seen by the guest depend significantly on the
12FPGA image.
13
14QEMU models the following FPGA images:
15
16``mps2-an385``
17  Cortex-M3 as documented in Arm Application Note AN385
18``mps2-an386``
19  Cortex-M4 as documented in Arm Application Note AN386
20``mps2-an500``
21  Cortex-M7 as documented in Arm Application Note AN500
22``mps2-an505``
23  Cortex-M33 as documented in Arm Application Note AN505
24``mps2-an511``
25  Cortex-M3 'DesignStart' as documented in Arm Application Note AN511
26``mps2-an521``
27  Dual Cortex-M33 as documented in Arm Application Note AN521
28``mps3-an524``
29  Dual Cortex-M33 on an MPS3, as documented in Arm Application Note AN524
30
31Differences between QEMU and real hardware:
32
33- AN385/AN386 remapping of low 16K of memory to either ZBT SSRAM1 or to
34  block RAM is unimplemented (QEMU always maps this to ZBT SSRAM1, as
35  if zbt_boot_ctrl is always zero)
36- AN524 remapping of low memory to either BRAM or to QSPI flash is
37  unimplemented (QEMU always maps this to BRAM, ignoring the
38  SCC CFG_REG0 memory-remap bit)
39- QEMU provides a LAN9118 ethernet rather than LAN9220; the only guest
40  visible difference is that the LAN9118 doesn't support checksum
41  offloading
42- QEMU does not model the QSPI flash in MPS3 boards as real QSPI
43  flash, but only as simple ROM, so attempting to rewrite the flash
44  from the guest will fail
45- QEMU does not model the USB controller in MPS3 boards
46