Add initial support for powerpc64le initialization. #267
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* Adds header definitions for PPC64le
* Adds support to construct the processor, core, cluster, package
and cache(L1i,L1d,L2 and L3) information reported by the system.
Test: Build and ran cpu_info on PPC64le linux machine. confirmed
that it properly reports the logical processors, cores, clusters,
packages and cache information.
test/name/power-features.cc
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| int b = (uint32_t) getauxval(AT_HWCAP2); | ||
| #endif //CPUINFO_MOCK // | ||
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| #if (b & CPUINFO_POWERPC_LINUX_FEATURE_ARCH_3_1) |
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Can you please explain how that is supposed to work?
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@malfet when AT_hwcap2 supports the feature arch_3_1(Power10) then cpuinfo_initialization should set these features mma,vsx
_```
#if (b & CPUINFO_POWERPC_LINUX_FEATURE_ARCH_3_1)
EXPECT_EQ(0, cpuinfo_has_powerpc_htm());
EXPECT_EQ(1, cpuinfo_has_powerpc_mma());
EXPECT_EQ(1, cpuinfo_has_powerpc_vsx());
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#if is a preprocessor directive, isn't it?
And b is not defined when preprocessor is invoked, so all those conditions will simply never be compiled, aren't they?
So, I would like to see some sort of a thorough test plan for this PR before accepting it
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Yes, you are right. All those conditions will not be compiled, and the test case will not throw any error.
I have used if-elseif conditions to make it work, and below is the debugging screenshot that is going through the if() condition.
Since CPUINFO_MOCK is not implemented for PPC64le, I have removed the redundant code. Please go through the latest code changes and let me know your review comments.
src/linux/processors.c
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| cpuinfo_log_info( | ||
| "failed to parse online status for processor %" PRIu32 " from %s", processor, processor_online_filename); | ||
| return false; |
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yeah, I will fix all the indent errors
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@malfet I have fixed indentation. could you review it
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@malfet could you review the patch again |
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Hi @malfet , Did you get a chance to review this patch? |
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@malfet I am waiting for your review. |
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@fbarchard @malfet can you review this. |
test/name/power-features.cc
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| int b = (uint32_t)getauxval(AT_HWCAP2); | ||
| #endif // CPUINFO_MOCK // | ||
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| #if (b & CPUINFO_POWERPC_LINUX_FEATURE_ARCH_3_1) |
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Can you please explain to me, when something like that would be evaluated to true?
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Yes , you are right . I have updated the code.
preprocessor code will never be compiled.
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I have updated the code. Please review it @malfet |
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@malfet can you review the latest code. |
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Pull Request Overview
This PR adds initial support for powerpc64le initialization including new header definitions, architectural decoding logic, and test coverage for POWER-specific features.
- Adds new cases to uarch-to-string conversion to support POWER7, POWER8, POWER9, and POWER10.
- Introduces PPC64-specific processing flows in CPU parsing, cache handling, and initialization.
- Updates configuration and test infrastructure to integrate PPC64 support.
Reviewed Changes
Copilot reviewed 18 out of 19 changed files in this pull request and generated no comments.
Show a summary per file
| File | Description |
|---|---|
| tools/cpu-info.c | New POWER architecture cases added in the uarch_to_string function. |
| test/name/power-features.cc | Added tests for POWER-specific features based on auxiliary vector flags. |
| test/init.cc | Conditionals to disable cache consistency tests for PPC64 are added. |
| src/powerpc/uarch.c, linux/ppc64-isa.c, linux/ppc64-hw.c | New implementations for decoding vendor, ISA, and hardware capabilities on PPC64. |
| src/powerpc/linux/cpuinfo.c | CPU parsing updated to support POWER processor architectures with proper logging. |
| src/powerpc/cache.c | New implementation for decoding cache information for PPC processors. |
| src/linux/processors.c & src/linux/api.h | Added functions to get processor online status on Linux. |
| src/init.c, internal-api.h, src/api.c | Updated PPC64 branches added to initialization and global data. |
| include/cpuinfo.h | Added PPC-specific fields and inline feature functions. |
| configure.py | Configures PPC64-specific source files and tests for build targets. |
Files not reviewed (1)
- CMakeLists.txt: Language not supported
| #endif | ||
| /** Clock rate (non-Turbo) of the core, in Hz */ | ||
| uint64_t frequency; | ||
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| bool disabled; |
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Please mention in PR description that it adds a new property (though I though there were already one) And where is it initialized for other architectures?
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Thanks @malfet for reviewing it. Updated the commit description and the Processor Version Register (PVR) on PowerPC (ppc64) architectures uniquely identifies the processor version and revision. Other CPU architectures provide similar capabilities, though they go by different names and mechanisms , for example
ARM / AArch64 : MIDR
Added header definitions for PPC64LE.
Implemented support to construct and report processor topology information including processor, core, cluster, package, PVR, and cache levels (L1i, L1d, L2, and L3).
Test:
Built and executed cpu_info on a PPC64LE Linux machine. Confirmed that it accurately reports logical processors, cores, clusters, packages, and cache information.
Ran unit tests and verified that there were no regressions.