On 8/8/22 04:13, Cédric Le Goater wrote:
> On 8/8/22 08:47, Cédric Le Goater wrote:
>> On 8/5/22 11:39, Daniel Henrique Barboza wrote:
>>> This will enable support for 'dumpdtb' and 'info fdt' HMP commands for
>>> all powernv machines.
>>
>> I might have missed some emails but dumpdtb is already suppported :
>> commit 8d4092614161 ("ppc/pnv: activate the "dumpdtb" option on the
>> powernv machine")
>
> ok. found the patchset "QMP/HMP: add 'dumpdtb' and 'info fdt' commands"
>
> 'info fdt' would have been of great help when we were developing the
> PowerNV machine. Initially, I was even using pmemsave to extract the
> FDT blob ... So this is a great idea ! (which needs a g_free() )
>
> Do we have something similar to dump ACPI tables, btw ?
In QEMU? No idea. I didn't find users of libfdt in x86 files so I didn't
bothered checking.
I am aware of something you can do in userland to dump the ACPI tables. I
did it once for research when I was working in the NUMA FORM2 extension
for pseries. This is the procedure do dump the ACPI SLIT table:
danielhb@ubuntu-vm:~$ sudo acpidump > acpidata.dat
[sudo] password for danielhb:
danielhb@ubuntu-vm:~$
danielhb@ubuntu-vm:~$ sudo acpixtract -sSLIT acpidata.dat
Intel ACPI Component Architecture
ACPI Binary Table Extraction Utility version 20200925
Copyright (c) 2000 - 2020 Intel Corporation
SLIT - 60 bytes written (0x0000003C) - slit.dat
danielhb@ubuntu-vm:~$
danielhb@ubuntu-vm:~$ iasl -d slit.dat
Intel ACPI Component Architecture
ASL+ Optimizing Compiler/Disassembler version 20200925
Copyright (c) 2000 - 2020 Intel Corporation
File appears to be binary: found 24 non-ASCII characters, disassembling
Binary file appears to be a valid ACPI table, disassembling
Input file slit.dat, Length 0x3C (60) bytes
ACPI: SLIT 0x0000000000000000 00003C (v01 BOCHS BXPCSLIT 00000001 BXPC 00000001)
Acpi Data Table [SLIT] decoded
Formatted output: slit.dsl - 1489 bytes
danielhb@ubuntu-vm:~$
danielhb@ubuntu-vm:~$ cat slit.dsl
/*
* Intel ACPI Component Architecture
* AML/ASL+ Disassembler version 20200925 (64-bit version)
* Copyright (c) 2000 - 2020 Intel Corporation
*
* Disassembly of slit.dat, Wed Jun 2 19:00:54 2021
*
* ACPI Data Table [SLIT]
*
* Format: [HexOffset DecimalOffset ByteLength] FieldName : FieldValue
*/
[000h 0000 4] Signature : "SLIT" [System Locality Information Table]
[004h 0004 4] Table Length : 0000003C
[008h 0008 1] Revision : 01
[009h 0009 1] Checksum : A0
[00Ah 0010 6] Oem ID : "BOCHS "
[010h 0016 8] Oem Table ID : "BXPCSLIT"
[018h 0024 4] Oem Revision : 00000001
[01Ch 0028 4] Asl Compiler ID : "BXPC"
[020h 0032 4] Asl Compiler Revision : 00000001
[024h 0036 8] Localities : 0000000000000004
[02Ch 0044 4] Locality 0 : 0A 16 16 16
[030h 0048 4] Locality 1 : 2C 0A 2C 2C
[034h 0052 4] Locality 2 : 42 42 0A 42
[038h 0056 4] Locality 3 : 58 58 58 0A
Raw Table Data: Length 60 (0x3C)
0000: 53 4C 49 54 3C 00 00 00 01 A0 42 4F 43 48 53 20 // SLIT<.....BOCHS
0010: 42 58 50 43 53 4C 49 54 01 00 00 00 42 58 50 43 // BXPCSLIT....BXPC
0020: 01 00 00 00 04 00 00 00 00 00 00 00 0A 16 16 16 // ................
0030: 2C 0A 2C 2C 42 42 0A 42 58 58 58 0A // ,.,,BB.BXXX.
danielhb@ubuntu-vm:~$
So basically a combination of acpidump and acpixtract commands in the guest.
Daniel
>
> Thanks,
>
> C.
>
>
>>>
>>> Cc: Cédric Le Goater <clg@kaod.org>
>>> Cc: Frederic Barrat <fbarrat@linux.ibm.com>
>>> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
>>> ---
>>> hw/ppc/pnv.c | 6 +++++-
>>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
>>> index d3f77c8367..f5162f8b7b 100644
>>> --- a/hw/ppc/pnv.c
>>> +++ b/hw/ppc/pnv.c
>>> @@ -608,7 +608,11 @@ static void pnv_reset(MachineState *machine)
>>> qemu_fdt_dumpdtb(fdt, fdt_totalsize(fdt));
>>> cpu_physical_memory_write(PNV_FDT_ADDR, fdt, fdt_totalsize(fdt));
>>> - g_free(fdt);
>>> + /*
>>> + * Update the machine->fdt pointer to enable support for
>>> + * 'dumpdtb' and 'info fdt' commands.
>>> + */
>>> + machine->fdt = fdt;
>>> }
>>> static ISABus *pnv_chip_power8_isa_create(PnvChip *chip, Error **errp)
>>
>