Attention is currently required from: Subrata Banik, Ravishankar Sarawadi, Kapil Porwal, Angel Pons, Arthur Heymans, Lean Sheng Tan, Werner Zeh, Sukumar Ghorai, Raj Astekar.
Hello build bot (Jenkins), Subrata Banik, Ravishankar Sarawadi, Kapil Porwal, Angel Pons, Arthur Heymans, Lean Sheng Tan, Werner Zeh, Raj Astekar,
I'd like you to reexamine a change. Please visit
https://review.coreboot.org/c/coreboot/+/70751
to look at the new patch set (#5).
Change subject: soc/intel/common: Fix cpu index calculation ......................................................................
soc/intel/common: Fix cpu index calculation
get_cpu_index() helper function returns cpu's index based on it's APIC id position from the ascending order list of cpus' APIC IDs. In order to calculate the cpu's index, the helper function needs to traverse through each cpu node to find their APIC IDs. So, the function traverse the CPU node list from the cpu whose APIC ID is 0 assuming it is the first cpu node in the list. This logic works fine where BSP's APIC ID is 0. But, starting from MTL, APIC ID for BSP need not be 0 as APIC ID numbering first get assigned for CPU Die Efficient cores, then Performance cores. Please refer section# 6.1 of doc#643504 for more details on APIC IDs.
Considering the APIC Id allotment for MTL cores, as existing code traversing begins from the cpu that has APIC Id#0 which may not be the first cpu node in the list so index calculation results in wrong value.
The patch addresses above described issue by traversing all the CPU nodes to calculate the cpu index.
TEST=Verified the the get_cpu_index helper function returns the correct index id for a CPU on Rex.
The coreboot log with code instrumentation, before this patch:
[DEBUG] my_apic_id:0x10 cpu_index: 0x6 [DEBUG] my_apic_id:0x11 cpu_index: 0x6 [DEBUG] my_apic_id:0x42 cpu_index: 0x6 [DEBUG] my_apic_id:0x21 cpu_index: 0x6 [DEBUG] my_apic_id:0x40 cpu_index: 0x6 [DEBUG] my_apic_id:0x31 cpu_index: 0x6 [DEBUG] my_apic_id:0x39 cpu_index: 0x6 [DEBUG] my_apic_id:0xa cpu_index: 0x3 [DEBUG] my_apic_id:0x0 cpu_index: 0x0 [DEBUG] my_apic_id:0x8 cpu_index: 0x2 [DEBUG] my_apic_id:0x4 cpu_index: 0x2 [DEBUG] my_apic_id:0x28 cpu_index: 0x6 [DEBUG] my_apic_id:0x2 cpu_index: 0x1 [DEBUG] my_apic_id:0x38 cpu_index: 0x6 [DEBUG] my_apic_id:0x29 cpu_index: 0x6 [DEBUG] my_apic_id:0xe cpu_index: 0x5 [DEBUG] my_apic_id:0x6 cpu_index: 0x2 [DEBUG] my_apic_id:0x20 cpu_index: 0x6 [DEBUG] my_apic_id:0x30 cpu_index: 0x6 [DEBUG] my_apic_id:0x19 cpu_index: 0x6 [DEBUG] my_apic_id:0xc cpu_index: 0x4 [DEBUG] my_apic_id:0x18 cpu_index: 0x6
We can see same cpu_index for multiple cores before fix.
After this patch.. [DEBUG] my_apic_id:0x10 cpu_index: 0x8 [DEBUG] my_apic_id:019 cpu_index: 0xb [DEBUG] my_apic_id:0x11 cpu_index: 0x9 [DEBUG] my_apic_id:0x18 cpu_index: 0xa [DEBUG] my_apic_id:0x40 cpu_index: 0x14 [DEBUG] my_apic_id:0x30 cpu_index: 0x10 [DEBUG] my_apic_id:0x42 cpu_index: 0x15 [DEBUG] my_apic_id:0xc cpu_index: 0x6 [DEBUG] my_apic_id:0x2 cpu_index: 0x1 [DEBUG] my_apic_id:0x29 cpu_index: 0xf [DEBUG] my_apic_id:0xe cpu_index: 0x7 [DEBUG] my_apic_id:0x20 cpu_index: 0xc [DEBUG] my_apic_id:0x0 cpu_index: 0x0 [DEBUG] my_apic_id:0x31 cpu_index: 0x11 [DEBUG] my_apic_id:0x28 cpu_index: 0xe [DEBUG] my_apic_id:0x21 cpu_index: 0xd [DEBUG] my_apic_id:0xa cpu_index: 0x5 [DEBUG] my_apic_id:0x38 cpu_index: 0x12 [DEBUG] my_apic_id:0x8 cpu_index: 0x4 [DEBUG] my_apic_id:0x4 cpu_index: 0x2 [DEBUG] my_apic_id:0x39 cpu_index: 0x13
Change-Id: I69e5e6231dd18b43d439340aaed50eb9edeca3b7 Signed-off-by: Sridhar Siricilla sridhar.siricilla@intel.com --- M src/cpu/x86/mp_init.c M src/soc/intel/common/block/acpi/cpu_hybrid.c 2 files changed, 84 insertions(+), 3 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/51/70751/5
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Sridhar Siricilla (Code Review)