[devel-6.6] [Feature] - AMD P-state / CPPC / ACPI platform_profile Backport for OpenAnolis Kernel 6.6 · Pull Request !7668 · anolis/cloud-kernel

bugzilla: https://bugzilla.openanolis.cn/show_bug.cgi?id=36733

**AMD P-state / CPPC / ACPI platform_profile Backport for OpenAnolis Kernel 6.6**

**Patch List:**

```
amd-pstate: Fix memory leak in amd_pstate_epp_cpu_init()
amd-pstate: Update cppc_req_cached in fast_switch case
amd-pstate: Make certain freq_attrs conditionally visible
x86/cpufeatures: Add AMD CPPC Performance Priority feature.
cpufreq: ACPI: Simplify MSR read on the boot CPU
bitfield: Add FIELD_MODIFY() helper
amd-pstate: Add support for CPPC_REQ2 and FLOOR_PERF
cpufreq/amd-pstate: Fix a regression leading to EPP 0 after resume
cpufreq/amd-pstate: Fix a regression leading to EPP 0 after hibernate
amd-pstate: Add sysfs support for floor_freq and floor_count
amd-pstate: Introduce a tracepoint trace_amd_pstate_cppc_req2()
amd-pstate-ut: Add module parameter to select testcases
amd-pstate-ut: Add a testcase to validate the visibility of driver attributes
Documentation/amd-pstate: List amd_pstate_hw_prefcore sysfs file
Documentation/amd-pstate: List amd_pstate_prefcore_ranking sysfs file
Documentation/amd-pstate: Add documentation for amd_pstate_floor_{freq,count}
cpufreq/amd-pstate: Cache the max frequency in cpudata
Documentation: amd-pstate: fix dead links in the reference section
cpufreq/amd-pstate: Use sysfs_match_string() for epp
cpufreq/amd-pstate: Add dynamic energy performance preference
Documentation: amd-pstate: introduce amd-pstate preferred core
Documentation: introduce amd-pstate preferrd core mode kernel command line options
cpufreq/amd-pstate: add kernel command line to override dynamic epp
anolis: configs: disable ASUS_WMI, IDEAPAD_LAPTOP and THINKPAD_ACPI
ACPI: platform-profile: Add a name member to handlers
ACPI: platform_profile: Add device pointer into platform profile handler
ACPI: platform-profile: add platform_profile_cycle()
ACPI: platform_profile: Add platform handler argument to platform_profile_remove()
ACPI: platform_profile: Pass the profile handler into platform_profile_notify()
ACPI: platform_profile: Move sanity check out of the mutex
ACPI: platform_profile: Move matching string for new profile out of mutex
ACPI: platform_profile: Use guard(mutex) for register/unregister
ACPI: platform_profile: Use `scoped_cond_guard`
Revert "ACPI: platform-profile: Fix CFI violation when accessing sysfs files"
ACPI: add missing MODULE_DESCRIPTION() macros
ACPI: platform_profile: Create class for ACPI platform profile
ACPI: platform_profile: Add name attribute to class interface
ACPI: platform_profile: Add choices attribute for class interface
ACPI: platform_profile: Add profile attribute for class interface
ACPI: platform_profile: Notify class device from platform_profile_notify()
ACPI: platform_profile: Notify change events on register and unregister
ACPI: platform_profile: Only show profiles common for all handlers
ACPI: platform_profile: Add concept of a "custom" profile
ACPI: platform_profile: Make sure all profile handlers agree on profile
ACPI: platform_profile: Check all profile handler to calculate next
ACPI: platform_profile: Allow multiple handlers
ACPI: platform_profile: Replace *class_dev member with class_dev
ACPI: platform_profile: Add devm_platform_profile_register()
ACPI: platform_profile: Let drivers set drvdata to the class device
ACPI: platform_profile: Remove platform_profile_handler from callbacks
ACPI: platform_profile: Add `ops` member to handlers
ACPI: platform_profile: Add `probe` to platform_profile_ops
platform/x86: amd: pmf: sps: Use devm_platform_profile_register()
ACPI: platform_profile: Remove platform_profile_handler from exported symbols
cpufreq/amd-pstate: Add support for platform profile class
ACPI: platform-profile: Fix CFI violation when accessing sysfs files
cpufreq: Pass the policy to cpufreq_driver->adjust_perf()
cpufreq/amd-pstate: Pass the policy to amd_pstate_update()
cpufreq/amd-pstate: Add static asserts for EPP indices
cpufreq/amd-pstate: Add support for raw EPP writes
cpufreq/amd-pstate-ut: Add a unit test for raw EPP
MAINTAINERS: amd-pstate: Step down as maintainer, add Prateek as reviewer
```

---

**Patch Series Overview:**

This patch series consists of 62 commits backporting AMD P-state / CPPC and ACPI platform_profile enhancements from the AMD `Linux_Backport` tree (https://github.com/AMDEPYC/Linux_Backport.git, branch `after_798c47593cca`) onto the OpenAnolis 6.6 kernel. The changes span the core amd-pstate driver, ACPI platform_profile subsystem (full refactor into a class-based, multi-handler framework), the cpufreq core (`adjust_perf()` API change), the AMD PMF SPS driver, x86 CPU-feature and MSR-index definitions, the `bitfield` helpers, the amd-pstate-ut unit test framework, and the amd-pstate documentation. Together they enable AMD CPPC "Performance Priority" (CPPC_REQ2 / FLOOR_PERF), dynamic and raw EPP writes, amd-pstate integration with the new platform_profile class, and several stability fixes for the amd-pstate driver. Base commit: `6a2554749a43`.

---

**Key Bug Fixes:**

- **EPP 0 regression after resume**: Fixed a regression where the Energy Performance Preference was incorrectly reset to 0 on system resume, causing performance degradation on wake.
- **EPP 0 regression after hibernate**: Fixed the corresponding EPP-reset-to-0 regression on the hibernate path.
- **Memory leak in amd_pstate_epp_cpu_init()**: Fixed a leak where the allocated `cpudata` object was not freed on the error path during EPP CPU initialization.
- **Stale cppc_req_cached in fast_switch**: Fixed `cppc_req_cached` not being updated in the `fast_switch` path, causing subsequent EPP/perf comparisons to see stale state.
- **ACPI platform-profile CFI violation**: Restored the CFI fix for sysfs file accessors (previously reverted in this same series so the platform_profile locking rework could be applied cleanly, then reapplied at the new location).

---

**Feature Additions:**

- **CPPC_REQ2 / FLOOR_PERF support**: Added support for the new `MSR_AMD_CPPC_REQ2` register and its `FLOOR_PERF` field on processors that advertise the AMD CPPC Performance Priority feature (new `X86_FEATURE_CPPC_PERF_PRIO` bit). Includes `amd_pstate_floor_freq` / `amd_pstate_floor_count` sysfs attributes and a new `trace_amd_pstate_cppc_req2()` tracepoint. Floor-perf is saved at boot and restored in suspend / offline / exit paths.
- **ACPI platform_profile class-based, multi-handler framework**: Re-architected the ACPI platform_profile subsystem to expose each handler as a class device with `name` / `choices` / `profile` sysfs attributes, a `platform_profile_cycle()` helper, multi-handler registration via `devm_platform_profile_register()`, an `ops` (incl. `probe`) interface, and intersection-of-common-profiles semantics (with a "custom" pseudo-profile shown when handlers disagree).
- **amd-pstate integration with platform_profile class**: amd-pstate now registers a platform_profile handler so that platform power profiles (balanced / performance / quiet) are coordinated through the standard sysfs class interface.
- **amd-pmf SPS migrated to devm_platform_profile_register()**: The AMD PMF SPS driver was converted to the new devm-managed registration, removing manual cleanup paths.
- **Dynamic EPP + kernel command-line override**: Added a dynamic EPP mode and the `amd_pstate_epp=` kernel command-line option to override the dynamically selected value at boot.
- **Raw EPP writes**: The `energy_performance_preference` sysfs node now also accepts raw numeric EPP values (with new amd-pstate-ut coverage), in addition to the named profile strings.

---

**Logic & Performance Improvements:**

- **cpufreq core API change**: `cpufreq_driver->adjust_perf()` and `amd_pstate_update()` now take a `struct cpufreq_policy *` directly, removing redundant `cpufreq_cpu_get()` lookups in hot paths.
- **Cache max frequency in cpudata**: The per-CPU maximum frequency is computed once at init and cached in `amd_cpudata`, replacing repeated `perf_to_freq()` calls in the policy limit paths.
- **platform_profile locking modernization**: Converted register/unregister and notify paths to `guard(mutex)` and `scoped_cond_guard`, moved sanity checks and the new-profile string match outside the mutex, and made `platform_profile_notify()` / `_remove()` take the handler argument explicitly — eliminating implicit-global-handler assumptions that blocked multi-handler support.
- **Bitfield + EPP-index hardening**: Introduced a new generic `FIELD_MODIFY()` bitfield helper used by the CPPC_REQ2 paths, added static asserts on EPP enum indices, and switched EPP string matching to `sysfs_match_string()`.
- **Simpler boot-CPU MSR read in acpi-cpufreq**: Replaced the open-coded "are we on the boot CPU?" dance in `cpufreq: ACPI` with a direct `rdmsr()` on the boot CPU, removing an unnecessary IPI.

---

**Unit Test Framework (amd-pstate-ut):**

- **Module parameter for testcase selection**: Added a module parameter to select individual test cases at load time, enabling targeted regression testing.
- **Driver-attribute visibility test**: Added a test case that validates which per-CPU amd-pstate sysfs attributes are visible under each driver mode.
- **Raw EPP unit test**: Added a unit test that exercises the new raw EPP write path.

---

**Documentation:**

- **Preferred core sysfs files**: Documented `amd_pstate_hw_prefcore` and `amd_pstate_prefcore_ranking`.
- **floor_freq and floor_count**: Documented the new `amd_pstate_floor_freq` and `amd_pstate_floor_count` sysfs attributes introduced with CPPC_REQ2.
- **Preferred core admin guide + kernel cmdline**: Added a preferred-core overview section and documented the corresponding kernel command-line options.
- **Dead link fixes**: Corrected broken reference links in the amd-pstate documentation.

---

**Anolis-Specific Change:**

- **anolis: configs: disable ASUS_WMI, IDEAPAD_LAPTOP and THINKPAD_ACPI**: Disabled three consumer-laptop platform_profile vendor drivers under `anolis/configs/L2-OPTIONAL/x86/` that are not required on Anolis server profiles.

---

**Maintainership:**

- **MAINTAINERS**: amd-pstate — Gautham R. Shenoy steps down as maintainer; K Prateek Nayak added as a reviewer.

---
---

**Unit Test**

**Boot Kernel With amd_pstate=active** 
```
uname -r
cat /proc/cmdline
cat /sys/devices/system/cpu/amd_pstate/status
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
cat /sys/devices/system/cpu/cpu0/cpufreq/energy_performance_preference
```

**Expected Output** 
```
6.6.102-with_patch+
BOOT_IMAGE=(hd4,gpt2)/vmlinuz-6.6.102-with_patch+ root=/dev/mapper/ao_anolis-root ro resume=/dev/mapper/ao_anolis-swap rd.lvm.lv=ao_anolis/root rd.lvm.lv=ao_anolis/swap rhgb quiet amd_pstate=active
active
amd-pstate-epp
performance
performance
```

**CPPC-derived freq math matches cpufreq sysfs** 
```
HI=$(cat /sys/devices/system/cpu/cpu0/acpi_cppc/highest_perf)
NF=$(cat /sys/devices/system/cpu/cpu0/acpi_cppc/nominal_freq)
NP=$(cat /sys/devices/system/cpu/cpu0/acpi_cppc/nominal_perf)
LNL=$(cat /sys/devices/system/cpu/cpu0/acpi_cppc/lowest_nonlinear_perf)
LO=$(cat /sys/devices/system/cpu/cpu0/acpi_cppc/lowest_perf)
echo "highest_perf=$HI  nominal_freq=$NF MHz  nominal_perf=$NP"
echo "max  = $HI * $NF / $NP = $(echo "scale=2; $HI*$NF/$NP" | bc) MHz   vs cpuinfo_max_freq=$(cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq) kHz"
echo "lnl  = $LNL * $NF / $NP = $(echo "scale=2; $LNL*$NF/$NP" | bc) MHz   vs amd_pstate_lowest_nonlinear_freq=$(cat /sys/devices/system/cpu/cpu0/cpufreq/amd_pstate_lowest_nonlinear_freq) kHz"
echo "min  = $LO * $NF / $NP = $(echo "scale=2; $LO*$NF/$NP" | bc) MHz   vs cpuinfo_min_freq=$(cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq) kHz"
```

**Output:** 
```
highest_perf=255  nominal_freq=2451 MHz  nominal_perf=208
max  = 255 * 2451 / 208 = 3004.83 MHz   vs cpuinfo_max_freq=3004832 kHz
lnl  = 161 * 2451 / 208 = 1897.16 MHz   vs amd_pstate_lowest_nonlinear_freq=1897169 kHz
min  = 34 * 2451 / 208 = 400.64 MHz   vs cpuinfo_min_freq=400645 kHz

```

**AMD CPPC MSRs — raw and decoded** 
```
sudo modprobe msr
 
for entry in "CAP1   0xc00102b0" "ENABLE 0xc00102b1" "CAP2   0xc00102b2" \
             "REQ    0xc00102b3" "STATUS 0xc00102b4" "REQ2   0xc00102b5"; do
    name=$(echo "$entry" | awk '{print $1}')
    addr=$(echo "$entry" | awk '{print $2}')
    val=$(sudo rdmsr -p 0 $addr 2>&1)
    printf "  %-6s %-12s = 0x%s\n" "$name" "$addr" "$val"
done
 
echo ""
echo "CAP1 decoded:"
echo "  lowest_perf       = $(sudo rdmsr -p 0 0xc00102b0 -u --bitfield 7:0)"
echo "  lownonlin_perf    = $(sudo rdmsr -p 0 0xc00102b0 -u --bitfield 15:8)"
echo "  nominal_perf      = $(sudo rdmsr -p 0 0xc00102b0 -u --bitfield 23:16)"
echo "  highest_perf      = $(sudo rdmsr -p 0 0xc00102b0 -u --bitfield 31:24)"
 
echo ""
echo "REQ decoded:"
echo "  max_perf          = $(sudo rdmsr -p 0 0xc00102b3 -u --bitfield 7:0)"
echo "  min_perf          = $(sudo rdmsr -p 0 0xc00102b3 -u --bitfield 15:8)"
echo "  des_perf          = $(sudo rdmsr -p 0 0xc00102b3 -u --bitfield 23:16)"
echo "  epp_perf          = $(sudo rdmsr -p 0 0xc00102b3 -u --bitfield 31:24)"
 
echo "ENABLE bit 0  = $(sudo rdmsr -p 0 0xc00102b1 -u --bitfield 0:0)"
echo "STATUS        = $(sudo rdmsr -p 0 0xc00102b4)"
```

**Output:**

```
CAP1   0xc00102b0   = 0xffd0a122ffd0a122
  ENABLE 0xc00102b1   = 0x1
  CAP2   0xc00102b2   = 0x0
  REQ    0xc00102b3   = 0xa2ff
  STATUS 0xc00102b4   = 0x0
  REQ2   0xc00102b5   = rdmsr: CPU 0 cannot read MSR 0xc00102b5
 
CAP1 decoded:
  lowest_perf       = 34
  lownonlin_perf    = 161
  nominal_perf      = 208
  highest_perf      = 255
 
REQ decoded:
  max_perf          = 255
  min_perf          = 162
  des_perf          = 0
  epp_perf          = 0
ENABLE bit 0  = 1
STATUS        = 0x0
```

类型	指派人员	状态
审查	Tianjia Zhang 王鹏 xunlei 半叶枫尘 Artie Ding winterddd xueshuai 赵鑫鹏 dtc 冯光辉 Guixin Liu kun-llfl Xuchun Shang XiangZao	已完成 (0/0人)
测试	小龙	进行中 (0/1人)

GVPanolis/cloud-kernel

搜索帮助

GVP anolis/cloud-kernel