On 8/5/24 6:04 PM, Gregor Haas wrote:
This patch series adds support for specifying OpenSBI domains on the QEMU
command line. A simple example of what this looks like is below, including
mapping the board's UART into the secondary domain:
qemu-system-riscv64 -machine virt -bios fw_jump.bin -cpu max -smp 2 -m 4G
-nographic \
-device opensbi-memregion,id=mem,base=0xBC000000,order=26,mmio=false \
-device
opensbi-memregion,id=uart,base=0x10000000,order=12,mmio=true,device0="/soc/serial@10000000"
\
-device
opensbi-domain,id=domain,possible-harts=0-1,boot-hart=0x0,next-addr=0xBC000000,next-mode=1,region0=mem,perms0=0x3f,region1=uart,perms1=0x3f
As a result of the above configuration, QEMU will add the following subnodes to
the device tree:
chosen {
opensbi-domains {
compatible = "opensbi,domain,config";
domain {
next-mode = <0x01>;
next-addr = <0x00 0xbc000000>;
boot-hart = <0x03>;
regions = <0x8000 0x3f 0x8002 0x3f>;
possible-harts = <0x03 0x01>;
phandle = <0x8003>;
compatible = "opensbi,domain,instance";
};
uart {
phandle = <0x8002>;
devices = <0x1800000>;
mmio;
order = <0x0c>;
base = <0x00 0x10000000>;
compatible = "opensbi,domain,memregion";
};
mem {
phandle = <0x8000>;
order = <0x1a>;
base = <0x00 0xbc000000>;
compatible = "opensbi,domain,memregion";
};
};
};
This results in OpenSBI output as below, where regions 01-03 are inherited from
the root domain and regions 00 and 04 correspond to the user specified ones:
Domain1 Name : domain
Domain1 Boot HART : 0
Domain1 HARTs : 0,1
Domain1 Region00 : 0x0000000010000000-0x0000000010000fff M: (I,R,W,X)
S/U: (R,W,X)
Domain1 Region01 : 0x0000000002000000-0x000000000200ffff M: (I,R,W)
S/U: ()
Domain1 Region02 : 0x0000000080080000-0x000000008009ffff M: (R,W) S/U:
()
Domain1 Region03 : 0x0000000080000000-0x000000008007ffff M: (R,X) S/U:
()
Domain1 Region04 : 0x00000000bc000000-0x00000000bfffffff M: (R,W,X)
S/U: (R,W,X)
Domain1 Next Address : 0x00000000bc000000
Domain1 Next Arg1 : 0x0000000000000000
Domain1 Next Mode : S-mode
Domain1 SysReset : no
Domain1 SysSuspend : no
I believe we need OpenSBI patches for this output, don't we? If I try this
example using stock
OpenSBI 1.5.1 from QEMU this happens:
OpenSBI v1.5.1
____ _____ ____ _____
/ __ \ / ____| _ \_ _|
| | | |_ __ ___ _ __ | (___ | |_) || |
| | | | '_ \ / _ \ '_ \ \___ \| _ < | |
| |__| | |_) | __/ | | |____) | |_) || |_
\____/| .__/ \___|_| |_|_____/|____/_____|
| |
|_|
sbi_domain_finalize: platform domains_init() failed (error -3)
init_coldboot: domain finalize failed (error -3)
(--- hangs ---)
It's not a big deal or a blocker to have this merged in QEMU regardless, but it
would be nice
to have this documented somewhere (perhaps a new doc file). This would prevent
users from trying
to use the device without the proper support.
This can be done after this patch is queued though. Thanks,
Daniel
v3:
- Addressed review comments from v2 by adding default values to new properties.
This results in concrete errors at QEMU configuration time if a mandatory
property (as mandated by the OpenSBI spec) is not provided.
- Changed command line encoding for the possible-harts field from a CPU bitmask
(e.g. where bit X is set if CPU X is a possible hart) to a range format (e.g.
the possible harts should be CPUs X-Y, where Y >= X). This does constrain the
hart assignment to consecutive ranges of harts, but this constraint is also
present for other QEMU subsystems (such as NUMA).
- Added create_fdt_one_device(), which is invoked when scanning the device tree
for a memregion's devices. This function allocates a phandle for a region's
device if one does not yet exist.
v2:
- Addressed review comments from v1. Specifically, renamed domain.{c,h} ->
opensbi_domain.{c,h} to increase clarity of what these files do. Also, more
consistently use g_autofree for dynamically allocated variables
- Added an "assign" flag to OpenSBIDomainState, which indicates whether to
assign the domain's boot hart to it at domain parsing time.
Gregor Haas (1):
Add support for generating OpenSBI domains in the device tree
MAINTAINERS | 7 +
hw/riscv/Kconfig | 4 +
hw/riscv/meson.build | 1 +
hw/riscv/opensbi_domain.c | 542 ++++++++++++++++++++++++++++++
hw/riscv/virt.c | 3 +
include/hw/riscv/opensbi_domain.h | 50 +++
6 files changed, 607 insertions(+)
create mode 100644 hw/riscv/opensbi_domain.c
create mode 100644 include/hw/riscv/opensbi_domain.h
