linux-stable.git/drivers/acpi/cppc_acpi.c, branch linux-6.11.y

ACPI: CPPC: Fix _CPC register setting issue

2024-12-05T12:52:53+00:00

[ Upstream commit 2388b266c9fcc7c9169ba85c7f9ebe325b7622d7 ]

Since commit 60949b7b8054 ("ACPI: CPPC: Fix MASK_VAL() usage"), _CPC
registers cannot be changed from 1 to 0.

It turns out that there is an extra OR after MASK_VAL_WRITE(), which
has already ORed prev_val with the register mask.

Remove the extra OR to fix the problem.

Fixes: 60949b7b8054 ("ACPI: CPPC: Fix MASK_VAL() usage")
Signed-off-by: Lifeng Zheng 
Link: https://patch.msgid.link/20241113103309.761031-1-zhenglifeng1@huawei.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

ACPI: CPPC: Make rmw_lock a raw_spin_lock

2024-11-08T15:30:49+00:00

[ Upstream commit 1c10941e34c5fdc0357e46a25bd130d9cf40b925 ]

The following BUG was triggered:

=============================
[ BUG: Invalid wait context ]
6.12.0-rc2-XXX #406 Not tainted
-----------------------------
kworker/1:1/62 is trying to lock:
ffffff8801593030 (&cpc_ptr->rmw_lock){+.+.}-{3:3}, at: cpc_write+0xcc/0x370
other info that might help us debug this:
context-{5:5}
2 locks held by kworker/1:1/62:
  #0: ffffff897ef5ec98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x50
  #1: ffffff880154e238 (&sg_policy->update_lock){....}-{2:2}, at: sugov_update_shared+0x3c/0x280
stack backtrace:
CPU: 1 UID: 0 PID: 62 Comm: kworker/1:1 Not tainted 6.12.0-rc2-g9654bd3e8806 #406
Workqueue:  0x0 (events)
Call trace:
  dump_backtrace+0xa4/0x130
  show_stack+0x20/0x38
  dump_stack_lvl+0x90/0xd0
  dump_stack+0x18/0x28
  __lock_acquire+0x480/0x1ad8
  lock_acquire+0x114/0x310
  _raw_spin_lock+0x50/0x70
  cpc_write+0xcc/0x370
  cppc_set_perf+0xa0/0x3a8
  cppc_cpufreq_fast_switch+0x40/0xc0
  cpufreq_driver_fast_switch+0x4c/0x218
  sugov_update_shared+0x234/0x280
  update_load_avg+0x6ec/0x7b8
  dequeue_entities+0x108/0x830
  dequeue_task_fair+0x58/0x408
  __schedule+0x4f0/0x1070
  schedule+0x54/0x130
  worker_thread+0xc0/0x2e8
  kthread+0x130/0x148
  ret_from_fork+0x10/0x20

sugov_update_shared() locks a raw_spinlock while cpc_write() locks a
spinlock.

To have a correct wait-type order, update rmw_lock to a raw spinlock and
ensure that interrupts will be disabled on the CPU holding it.

Fixes: 60949b7b8054 ("ACPI: CPPC: Fix MASK_VAL() usage")
Signed-off-by: Pierre Gondois 
Link: https://patch.msgid.link/20241028125657.1271512-1-pierre.gondois@arm.com
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

cpufreq: CPPC: fix perf_to_khz/khz_to_perf conversion exception

2024-11-01T01:02:39+00:00

[ Upstream commit d93df29bdab133b85e94b3c328e7fe26a0ebd56c ]

When the nominal_freq recorded by the kernel is equal to the lowest_freq,
and the frequency adjustment operation is triggered externally, there is
a logic error in cppc_perf_to_khz()/cppc_khz_to_perf(), resulting in perf
and khz conversion errors.

Fix this by adding a branch processing logic when nominal_freq is equal
to lowest_freq.

Fixes: ec1c7ad47664 ("cpufreq: CPPC: Fix performance/frequency conversion")
Signed-off-by: liwei 
Acked-by: Viresh Kumar 
Link: https://patch.msgid.link/20241024022952.2627694-1-liwei728@huawei.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

ACPI: CPPC: Add support for setting EPP register in FFH

2024-10-10T10:03:10+00:00

[ Upstream commit aaf21ac93909e08a12931173336bdb52ac8499f1 ]

Some Asus AMD systems are reported to not be able to change EPP values
because the BIOS doesn't advertise support for the CPPC MSR and the PCC
region is not configured.

However the ACPI 6.2 specification allows CPC registers to be declared
in FFH:
```
Starting with ACPI Specification 6.2, all _CPC registers can be in
PCC, System Memory, System IO, or Functional Fixed Hardware address
spaces. OSPM support for this more flexible register space scheme
is indicated by the “Flexible Address Space for CPPC Registers” _OSC
bit.
```

If this _OSC has been set allow using FFH to configure EPP.

Reported-by: al0uette@outlook.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218686
Suggested-by: al0uette@outlook.com
Tested-by: vderp@icloud.com
Tested-by: al0uette@outlook.com
Signed-off-by: Mario Limonciello 
Link: https://patch.msgid.link/20240910031524.106387-1-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

ACPI: CPPC: Fix MASK_VAL() usage

2024-10-04T14:37:23+00:00

[ Upstream commit 60949b7b805424f21326b450ca4f1806c06d982e ]

MASK_VAL() was added as a way to handle bit_offset and bit_width for
registers located in system memory address space. However, while suited
for reading, it does not work for writing and result in corrupted
registers when writing values with bit_offset > 0. Moreover, when a
register is collocated with another one at the same address but with a
different mask, the current code results in the other registers being
overwritten with 0s. The write procedure for SYSTEM_MEMORY registers
should actually read the value, mask it, update it and write it with the
updated value. Moreover, since registers can be located in the same
word, we must take care of locking the access before doing it. We should
potentially use a global lock since we don't know in if register
addresses aren't shared with another _CPC package but better not
encourage vendors to do so. Assume that registers can use the same word
inside a _CPC package and thus, use a per _CPC package lock.

Fixes: 2f4a4d63a193 ("ACPI: CPPC: Use access_width over bit_width for system memory accesses")
Signed-off-by: Clément Léger 
Link: https://patch.msgid.link/20240826101648.95654-1-cleger@rivosinc.com
[ rjw: Dropped redundant semicolon ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

ACPI: CPPC: Replace ternary operator with umax()

2024-07-02T19:01:08+00:00

Replace ternary operator with umax() in cppc_find_dmi_mhz().

Signed-off-by: Prabhakar Pujeri 
[ rjw: Subject and changelog edits ]
Link: https://patch.msgid.link/20240626130941.1527127-2-prabhakar.pujeri@gmail.com
Signed-off-by: Rafael J. Wysocki

ACPI: CPPC: add sysfs entry for guaranteed performance

2024-06-13T19:15:56+00:00

Expose the CPPC guaranteed performance as reported by the platform through
GuaranteedPerformanceRegister.

The current value is already read in cppc_get_perf_caps() and stored in
struct cppc_perf_caps (to be used by the intel_pstate driver), so only the
attribute itself needs to be defined.

Signed-off-by: Petr Tesařík 
Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-cpufreq'

2024-05-13T18:13:48+00:00

Merge cpufreq updates for 6.10:

 - Rework the handling of disabled turbo in the intel_pstate driver and
   make it update the maximum CPU frequency consistently regardless of
   the reason on top of a number of cleanups (Rafael Wysocki).

 - Add missing checks for NULL .exit() cpufreq driver callback to the
   cpufreq core (Viresh Kumar).

 - Prevent pulicy->max from going above the frequency QoS maximum value
   when cpufreq_frequency_table_verify() is used (Xuewen Yan).

 - Prevent a negative CPU number or frequency value from being printed
   if they are really large (Joshua Yeong).

 - Update MAINTAINERS entry for amd-pstate to add two new submaintainers
   and a designated reviewer (Huang Rui).

 - Clean up the amd-pstate driver and update its documentation (Gautham
   Shenoy).

 - Fix the highest frequency issue in the amd-pstate driver which limits
   performance (Perry Yuan).

 - Enable CPPC v2 for certain processors in the family 17H, as requested
   by TR40 processor users who expect improved performance and lower
   system temperature (Perry Yuan).

 - Change latency and delay values to be read from platform firmware
   firstly for more accurate timing (Perry Yuan).

 - A new quirk is introduced for supporting amd-pstate on legacy
   processors which either lack CPPC capability, or only only have CPPC
   v2 capability (Perry Yuan).

 - Sun50i: Add support for opp_supported_hw, H616 platform and general
   cleanups (Andre Przywara, Martin Botka, Brandon Cheo Fusi, Dan
   Carpenter, Viresh Kumar).

 - CPPC: Fix possible null pointer dereference (Aleksandr Mishin).

 - Eliminate uses of of_node_put() (Javier Carrasco, and Shivani Gupta).

 - brcmstb-avs: ISO C90 forbids mixed declarations (Portia Stephens).

 - mediatek: Add support for MT7988A (Sam Shih).

 - cpufreq-qcom-hw: Add SM4450 compatibles in DT bindings (Tengfei Fan).

 - Fix struct cpudata::epp_cached kernel-doc in the intel_pstate cpufreq
   driver (Jeff Johnson).

* pm-cpufreq: (46 commits)
  cpufreq: amd-pstate: fix the highest frequency issue which limits performance
  cpufreq: intel_pstate: fix struct cpudata::epp_cached kernel-doc
  cpufreq: Fix up printing large CPU numbers and frequency values
  MAINTAINERS: cpufreq: amd-pstate: Add co-maintainers and reviewer
  cpufreq: amd-pstate: remove unused variable lowest_nonlinear_freq
  cpufreq: amd-pstate: fix code format problems
  cpufreq: amd-pstate: Add quirk for the pstate CPPC capabilities missing
  cppc_acpi: print error message if CPPC is unsupported
  cpufreq: amd-pstate: get transition delay and latency value from ACPI tables
  cpufreq: amd-pstate: Bail out if min/max/nominal_freq is 0
  cpufreq: amd-pstate: Remove amd_get_{min,max,nominal,lowest_nonlinear}_freq()
  cpufreq: amd-pstate: Unify computation of {max,min,nominal,lowest_nonlinear}_freq
  cpufreq: amd-pstate: Document the units for freq variables in amd_cpudata
  cpufreq: amd-pstate: Document *_limit_* fields in struct amd_cpudata
  dt-bindings: cpufreq: cpufreq-qcom-hw: Add SM4450 compatibles
  cpufreq: sun50i: fix error returns in dt_has_supported_hw()
  cpufreq: brcmstb-avs-cpufreq: ISO C90 forbids mixed declarations
  cpufreq: dt-platdev: eliminate uses of of_node_put()
  cpufreq: dt: eliminate uses of of_node_put()
  cpufreq: ti: Implement scope-based cleanup in ti_cpufreq_match_node()
  ...

cppc_acpi: print error message if CPPC is unsupported

2024-04-26T17:35:38+00:00

The amd-pstate driver can fail when _CPC objects are not supported by
the CPU. However, the current error message is ambiguous (see below) and
there is no clear way for attributing the failure of the amd-pstate
driver to the lack of CPPC support.

[    0.477523] amd_pstate: the _CPC object is not present in SBIOS or ACPI disabled

Fix this by adding an debug message to notify the user if the amd-pstate
driver failed to load due to CPPC not be supported by the CPU

Reviewed-by: Mario Limonciello 
Reviewed-by: Gautham R. Shenoy 
Tested-by: Dhananjay Ugwekar 
Signed-off-by: Perry Yuan 
Acked-by: Huang Rui 
Signed-off-by: Rafael J. Wysocki

ACPI: CPPC: Fix access width used for PCC registers

2024-04-22T16:58:46+00:00

commit 2f4a4d63a193 ("ACPI: CPPC: Use access_width over bit_width for system
memory accesses") modified cpc_read()/cpc_write() to use access_width to
read CPC registers.

However, for PCC registers the access width field in the ACPI register
macro specifies the PCC subspace ID.  For non-zero PCC subspace ID it is
incorrectly treated as access width. This causes errors when reading
from PCC registers in the CPPC driver.

For PCC registers, base the size of read/write on the bit width field.
The debug message in cpc_read()/cpc_write() is updated to print relevant
information for the address space type used to read the register.

Fixes: 2f4a4d63a193 ("ACPI: CPPC: Use access_width over bit_width for system memory accesses")
Signed-off-by: Vanshidhar Konda 
Tested-by: Jarred White 
Reviewed-by: Jarred White 
Reviewed-by: Easwar Hariharan 
Cc: 5.15+  # 5.15+
Signed-off-by: Rafael J. Wysocki