The PAPR platform describes an OS environment that's presented by
a combination of a hypervisor and firmware. The features it specifies
require collaboration between the firmware and the hypervisor.
Since the beginning, the runtime component of the firmware (RTAS) has
been implemented as a 20 byte shim which simply forwards it to
a hypercall implemented in qemu. The boot time firmware component is
SLOF - but a build that's specific to qemu, and has always needed to be
updated in sync with it. Even though we've managed to limit the amount
of runtime communication we need between qemu and SLOF, there's some,
and it has become increasingly awkward to handle as we've implemented
new features.
This implements a boot time OF client interface (CI) which is
enabled by a new "x-vof" pseries machine option (stands for "Virtual
Open
Firmware). When enabled, QEMU implements the custom H_OF_CLIENT hcall
which implements Open Firmware Client Interface (OF CI). This allows
using a smaller stateless firmware which does not have to manage
the device tree.
The new "vof.bin" firmware image is included with source code under
pc-bios/. It also includes RTAS blob.
This implements a handful of CI methods just to get -kernel/-initrd
working. In particular, this implements the device tree fetching and
simple memory allocator - "claim" (an OF CI memory allocator) and
updates
"/memory@0/available" to report the client about available memory.
This implements changing some device tree properties which we know how
to deal with, the rest is ignored. To allow changes, this skips
fdt_pack() when x-vof=on as not packing the blob leaves some room for
appending.
In absence of SLOF, this assigns phandles to device tree nodes to make
device tree traversing work.
When x-vof=on, this adds "/chosen" every time QEMU (re)builds a tree.
This adds basic instances support which are managed by a hash map
ihandle -> [phandle].
Before the guest started, the used memory is:
0..e60 - the initial firmware
8000..10000 - stack
400000.. - kernel
3ea0000.. - initramdisk
This OF CI does not implement "interpret".
Unlike SLOF, this does not format uninitialized nvram. Instead, this
includes a disk image with pre-formatted nvram.
With this basic support, this can only boot into kernel directly.
However this is just enough for the petitboot kernel and initradmdisk to
boot from any possible source. Note this requires reasonably recent
guest
kernel with:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=df5be5be8735
The immediate benefit is much faster booting time which especially
crucial with fully emulated early CPU bring up environments. Also this
may come handy when/if GRUB-in-the-userspace sees light of the day.
This separates VOF and sPAPR in a hope that VOF bits may be reused by
other POWERPC boards which do not support pSeries.
This make VOF optional, it is disabled by default, add --enable-vof
to ./configure to enable it.
This assumes potential support for booting from QEMU backends
such as blockdev or netdev without devices/drivers used.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
The example command line is:
/home/aik/pbuild/qemu-killslof-localhost-ppc64/qemu-system-ppc64 \
-nodefaults \
-chardev stdio,id=STDIO0,signal=off,mux=on \
-device spapr-vty,id=svty0,reg=0x71000110,chardev=STDIO0 \
-mon id=MON0,chardev=STDIO0,mode=readline \
-nographic \
-vga none \
-enable-kvm \
-m 8G \
-machine
pseries,x-vof=on,cap-cfpc=broken,cap-sbbc=broken,cap-ibs=broken,cap-ccf-assist=off
\
-kernel pbuild/kernel-le-guest/vmlinux \
-initrd pb/rootfs.cpio.xz \
-drive
id=DRIVE0,if=none,file=./p/qemu-killslof/pc-bios/vof-nvram.bin,format=raw
\
-global spapr-nvram.drive=DRIVE0 \
-snapshot \
-smp 8,threads=8 \
-L /home/aik/t/qemu-ppc64-bios/ \
-trace events=qemu_trace_events \
-d guest_errors \
-chardev socket,id=SOCKET0,server,nowait,path=qemu.mon.tmux26 \
-mon chardev=SOCKET0,mode=control
---
Changes:
v21:
* s/ld/ldz/ in entry.S
* moved CONFIG_VOF from default-configs/devices/ppc64-softmmu.mak to
Kconfig
* made CONFIG_VOF optional
* s/l.lds/vof.lds/
* force 32 BE in spapr_machine_reset() instead of the firmware
* added checks for non-null methods of VofMachineIfClass
* moved OF_STACK_SIZE to vof.h, renamed to VOF_..., added a better
comment
* added path_offset wrapper for handling mixed case for addresses
after "@" in node names
* changed getprop() to check for actual "name" property in the fdt
* moved VOF_MEM_READ/VOF_MEM_WRITE to vof.h for sharing as (unlike
similar
rtas_ld/ldl_be_*) they return error codes
* VOF_MEM_READ uses now address_space_read (it was
address_space_read_full
before, not sure why)
v20:
* compile vof.bin with -mcpu=power4 for better compatibility
* s/std/stw/ in entry.S to make it work on ppc32
* fixed dt_available property to support both 32 and 64bit
* shuffled prom_args handling code
* do not enforce 32bit in MSR (again, to support 32bit platforms)
v19:
* put bootargs in the FDT
* moved setting properties to a VOF machine hook
* moved fw_size and claim for it to vof_init()
* added CROSS to the VOF's makefile
* simplified phandles assigning
* pass MachineState to all machine hooks instead of calling
qdev_get_machine (following QOM)
* bunch of smaller changes and added comments
* added simple test to attempt to start with x-vof=on
v18:
* fixed top addr (max address for "claim") on radix - it equals to
ram_size
and vof->top_addr was uint32_t
* fixed "available" property which got broken in v14 but it is only
visible
to clients which care (== grub)
* reshuffled vof_dt_memory_available() calls, added vof_init() to allow
vof_claim() before rendering the FDT
v17:
* mv hw/ppc/vof.h include/hw/ppc/vof.h
* VofMachineIfClass -> VofMachineClass; it is not VofMachineInterface as
nobody used this scheme, usually "Interface" is dropped, a couple of
times
it is "xxxInterfaceClass" or "xxxIfClass", as used the latter as it is
used by include/hw/vmstate-if.h
* added SPDX
* other fixes from v16 review
v16:
* rebased on dwg/ppc-for-6.1
* s/SpaprVofInterface/VofMachineInterface/
v15:
* bugfix: claimed memory for the VOF itself
* ditched OF_STACK_ADDR and allocate one instead, now it starts from
0x8000
because it is aligned to its size (no particular reason though)
* coding style
* moved nvram.bin up one level
* ditched bool in the firmware
* made debugging code conditional using trace_event_get_state() +
qemu_loglevel_mask()
* renamed the CAS interface to SpaprVofInterface
* added "write" which for now dumps the message and ihandle via
trace point for early debug assistance
* commented on when we allocate of_instances in vof_build_dt()
* store fw_size is SpaprMachine to let spapr_vof_reset() claim it
* many small fixes from v14's review
v14:
* check for truncates in readstr()
* ditched a separate vof_reset()
* spapr->vof is a pointer now, dropped the "on" field
* removed rtas_base from vof and updated comment why we allow setting it
* added myself to maintainers
* updated commit log about blockdev and other possible platforms
* added a note why new hcall is 0x5
* no in place endianness convertion in spapr_h_vof_client
* converted all cpu_physical_memory_read/write to address_space_rw
* git mv hw/ppc/spapr_vof_client.c hw/ppc/spapr_vof.c
v13:
* rebase on latest ppc-for-6.0
* shuffled code around to touch spapr.c less
v12:
* split VOF and SPAPR
v11:
* added g_autofree
* fixed gcc warnings
* fixed few leaks
* added nvram image to make "nvram --print-config" not crash;
Note that contrary to MIN_NVRAM_SIZE (8 * KiB), the actual minimum size
is 16K, or it just does not work (empty output from "nvram")
v10:
* now rebased to compile with meson
v9:
* remove special handling of /rtas/rtas-size as now we always add it in
QEMU
* removed leftovers from scsi/grub/stdout/stdin/...
v8:
* no read/write/seek
* no @dev in instances
* the machine flag is "x-vof" for now
v7:
* now we have a small firmware which loads at 0 as SLOF and starts from
0x100 as SLOF
* no MBR/ELF/GRUB business in QEMU anymore
* blockdev is a separate patch
* networking is a separate patch
v6:
* borrowed a big chunk of commit log introduction from David
* fixed initial stack pointer (points to the highest address of stack)
* traces for "interpret" and others
* disabled translate_kernel_address() hack so grub can load (work in
progress)
* added "milliseconds" for grub
* fixed "claim" allocator again
* moved FDT_MAX_SIZE to spapr.h as spapr_of_client.c wants it too for
CAS
* moved the most code possible from spapr.c to spapr_of_client.c, such
as
RTAS, prom entry and FDT build/finalize
* separated blobs
* GRUB now proceeds to its console prompt (there are still other issues)
* parse MBR/GPT to find PReP and load GRUB
v5:
* made instances keep device and chardev pointers
* removed VIO dependencies
* print error if RTAS memory is not claimed as it should have been
* pack FDT as "quiesce"
v4:
* fixed open
* validate ihandles in "call-method"
v3:
* fixed phandles allocation
* s/__be32/uint32_t/ as we do not normally have __be32 type in qemu
* fixed size of /chosen/stdout
* bunch of renames
* do not create rtas properties at all, let the client deal with it;
instead setprop allows changing these in the FDT
* no more packing FDT when bios=off - nobody needs it and getprop does
not
work otherwise
* allow updating initramdisk device tree properties (for zImage)
* added instances
* fixed stdout on OF's "write"
* removed special handling for stdout in OF client, spapr-vty handles it
instead
v2:
* fixed claim()
* added "setprop"
* cleaner client interface and RTAS blobs management
* boots to petitboot and further to the target system
* more trace points
v20
v20!
---
configure | 9 +
pc-bios/vof/Makefile | 23 +
include/hw/ppc/spapr.h | 25 +-
include/hw/ppc/vof.h | 55 ++
pc-bios/vof/vof.h | 43 ++
hw/ppc/spapr.c | 87 +++-
hw/ppc/spapr_hcall.c | 29 +-
hw/ppc/spapr_vof.c | 153 ++++++
hw/ppc/vof.c | 1052 +++++++++++++++++++++++++++++++++++++++
pc-bios/vof/bootmem.c | 14 +
pc-bios/vof/ci.c | 91 ++++
pc-bios/vof/libc.c | 92 ++++
pc-bios/vof/main.c | 21 +
tests/qtest/rtas-test.c | 17 +-
MAINTAINERS | 12 +
hw/ppc/Kconfig | 3 +
hw/ppc/meson.build | 3 +
hw/ppc/trace-events | 24 +
meson.build | 1 +
pc-bios/README | 2 +
pc-bios/vof-nvram.bin | Bin 0 -> 16384 bytes
pc-bios/vof.bin | Bin 0 -> 3784 bytes
pc-bios/vof/entry.S | 49 ++
pc-bios/vof/vof.lds | 48 ++
24 files changed, 1840 insertions(+), 13 deletions(-)
create mode 100644 pc-bios/vof/Makefile
create mode 100644 include/hw/ppc/vof.h
create mode 100644 pc-bios/vof/vof.h
create mode 100644 hw/ppc/spapr_vof.c
create mode 100644 hw/ppc/vof.c
create mode 100644 pc-bios/vof/bootmem.c
create mode 100644 pc-bios/vof/ci.c
create mode 100644 pc-bios/vof/libc.c
create mode 100644 pc-bios/vof/main.c
create mode 100644 pc-bios/vof-nvram.bin
create mode 100755 pc-bios/vof.bin
create mode 100644 pc-bios/vof/entry.S
create mode 100644 pc-bios/vof/vof.lds
diff --git a/configure b/configure
index 8dcb9965b24e..00dc29c027fa 100755
--- a/configure
+++ b/configure
@@ -445,6 +445,7 @@ fuse="auto"
fuse_lseek="auto"
multiprocess="auto"
slirp_smbd="$default_feature"
+vof="no"
malloc_trim="auto"
gio="$default_feature"
@@ -1561,6 +1562,10 @@ for opt do
;;
--disable-slirp-smbd) slirp_smbd=no
;;
+ --enable-vof) vof=yes
+ ;;
+ --disable-vof) vof=no
+ ;;
*)
echo "ERROR: unknown option $opt"
echo "Try '$0 --help' for more information"
@@ -1940,6 +1945,7 @@ disabled with --disable-FEATURE, default is
enabled if available
multiprocess Out of process device emulation support
gio libgio support
slirp-smbd use smbd (at path --smbd=*) in slirp networking
+ vof Virtual Open Firmware support (powerpc/pseries,
experimental)
NOTE: The object files are built at the place where configure is
launched
EOF
@@ -5555,6 +5561,9 @@ if test "$slirp_smbd" = "yes" ; then
echo "CONFIG_SLIRP_SMBD=y" >> $config_host_mak
echo "CONFIG_SMBD_COMMAND=\"$smbd\"" >> $config_host_mak
fi
+if test "$vof" = "yes" ; then
+ echo "CONFIG_VOF=y" >> $config_host_mak
+fi
if test "$vde" = "yes" ; then
echo "CONFIG_VDE=y" >> $config_host_mak
echo "VDE_LIBS=$vde_libs" >> $config_host_mak