<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/acpi/cppc_acpi.c, branch v6.1.124</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.124</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.1.124'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2024-12-14T18:53:18+00:00</updated>
<entry>
<title>ACPI: CPPC: Fix _CPC register setting issue</title>
<updated>2024-12-14T18:53:18+00:00</updated>
<author>
<name>Lifeng Zheng</name>
<email>zhenglifeng1@huawei.com</email>
</author>
<published>2024-11-13T10:33:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=4771ad8c70fe2a48fd34384540ed610335407215'/>
<id>urn:sha1:4771ad8c70fe2a48fd34384540ed610335407215</id>
<content type='text'>
[ 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 &lt;zhenglifeng1@huawei.com&gt;
Link: https://patch.msgid.link/20241113103309.761031-1-zhenglifeng1@huawei.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Make rmw_lock a raw_spin_lock</title>
<updated>2024-11-08T15:26:43+00:00</updated>
<author>
<name>Pierre Gondois</name>
<email>pierre.gondois@arm.com</email>
</author>
<published>2024-10-28T12:56:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=23039b4aaf1e82e0feea1060834d4ec34262e453'/>
<id>urn:sha1:23039b4aaf1e82e0feea1060834d4ec34262e453</id>
<content type='text'>
[ 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 (&amp;cpc_ptr-&gt;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 (&amp;rq-&gt;__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x50
  #1: ffffff880154e238 (&amp;sg_policy-&gt;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 &lt;pierre.gondois@arm.com&gt;
Link: https://patch.msgid.link/20241028125657.1271512-1-pierre.gondois@arm.com
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>cpufreq: CPPC: fix perf_to_khz/khz_to_perf conversion exception</title>
<updated>2024-11-01T00:56:05+00:00</updated>
<author>
<name>liwei</name>
<email>liwei728@huawei.com</email>
</author>
<published>2024-10-24T02:29:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=bc5085816e8afcd511dee31e1f6583e5d7e50ac2'/>
<id>urn:sha1:bc5085816e8afcd511dee31e1f6583e5d7e50ac2</id>
<content type='text'>
[ 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 &lt;liwei728@huawei.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Link: https://patch.msgid.link/20241024022952.2627694-1-liwei728@huawei.com
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>cpufreq/cppc: Move and rename cppc_cpufreq_{perf_to_khz|khz_to_perf}()</title>
<updated>2024-11-01T00:56:05+00:00</updated>
<author>
<name>Vincent Guittot</name>
<email>vincent.guittot@linaro.org</email>
</author>
<published>2023-12-11T10:48:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ff2a9c4029046a1b4bc64f47c7d248c056ba61f4'/>
<id>urn:sha1:ff2a9c4029046a1b4bc64f47c7d248c056ba61f4</id>
<content type='text'>
[ Upstream commit 50b813b147e9eb6546a1fc49d4e703e6d23691f2 ]

Move and rename cppc_cpufreq_perf_to_khz() and cppc_cpufreq_khz_to_perf() to
use them outside cppc_cpufreq in topology_init_cpu_capacity_cppc().

Modify the interface to use struct cppc_perf_caps *caps instead of
struct cppc_cpudata *cpu_data as we only use the fields of cppc_perf_caps.

cppc_cpufreq was converting the lowest and nominal freq from MHz to kHz
before using them. We move this conversion inside cppc_perf_to_khz and
cppc_khz_to_perf to make them generic and usable outside cppc_cpufreq.

No functional change

Signed-off-by: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Pierre Gondois &lt;pierre.gondois@arm.com&gt;
Acked-by: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Link: https://lore.kernel.org/r/20231211104855.558096-6-vincent.guittot@linaro.org
Stable-dep-of: d93df29bdab1 ("cpufreq: CPPC: fix perf_to_khz/khz_to_perf conversion exception")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Fix MASK_VAL() usage</title>
<updated>2024-10-17T13:20:39+00:00</updated>
<author>
<name>Clément Léger</name>
<email>cleger@rivosinc.com</email>
</author>
<published>2024-08-26T10:16:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f812ca13a0d3e3aa418da36b66ca40df0d6f9e60'/>
<id>urn:sha1:f812ca13a0d3e3aa418da36b66ca40df0d6f9e60</id>
<content type='text'>
[ 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 &gt; 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 &lt;cleger@rivosinc.com&gt;
Link: https://patch.msgid.link/20240826101648.95654-1-cleger@rivosinc.com
[ rjw: Dropped redundant semicolon ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Fix access width used for PCC registers</title>
<updated>2024-05-02T14:29:29+00:00</updated>
<author>
<name>Vanshidhar Konda</name>
<email>vanshikonda@os.amperecomputing.com</email>
</author>
<published>2024-04-11T23:18:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ba234a54ee56e5b23e763551e28fc220072d19c8'/>
<id>urn:sha1:ba234a54ee56e5b23e763551e28fc220072d19c8</id>
<content type='text'>
commit f489c948028b69cea235d9c0de1cc10eeb26a172 upstream.

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 &lt;vanshikonda@os.amperecomputing.com&gt;
Tested-by: Jarred White &lt;jarredwhite@linux.microsoft.com&gt;
Reviewed-by: Jarred White &lt;jarredwhite@linux.microsoft.com&gt;
Reviewed-by: Easwar Hariharan &lt;eahariha@linux.microsoft.com&gt;
Cc: 5.15+ &lt;stable@vger.kernel.org&gt; # 5.15+
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Fix bit_offset shift in MASK_VAL() macro</title>
<updated>2024-05-02T14:29:29+00:00</updated>
<author>
<name>Jarred White</name>
<email>jarredwhite@linux.microsoft.com</email>
</author>
<published>2024-04-09T05:23:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0f708a7e0abdceaaa35dc1844020e12a1153de53'/>
<id>urn:sha1:0f708a7e0abdceaaa35dc1844020e12a1153de53</id>
<content type='text'>
commit 05d92ee782eeb7b939bdd0189e6efcab9195bf95 upstream.

Commit 2f4a4d63a193 ("ACPI: CPPC: Use access_width over bit_width for
system memory accesses") neglected to properly wrap the bit_offset shift
when it comes to applying the mask. This may cause incorrect values to be
read and may cause the cpufreq module not be loaded.

[   11.059751] cpu_capacity: CPU0 missing/invalid highest performance.
[   11.066005] cpu_capacity: partial information: fallback to 1024 for all CPUs

Also, corrected the bitmask generation in GENMASK (extra bit being added).

Fixes: 2f4a4d63a193 ("ACPI: CPPC: Use access_width over bit_width for system memory accesses")
Signed-off-by: Jarred White &lt;jarredwhite@linux.microsoft.com&gt;
Cc: 5.15+ &lt;stable@vger.kernel.org&gt; # 5.15+
Reviewed-by: Vanshidhar Konda &lt;vanshikonda@os.amperecomputing.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Use access_width over bit_width for system memory accesses</title>
<updated>2024-05-02T14:29:29+00:00</updated>
<author>
<name>Jarred White</name>
<email>jarredwhite@linux.microsoft.com</email>
</author>
<published>2024-03-01T19:25:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=01fc53be672acae37e611c80cc0b4f3939584de3'/>
<id>urn:sha1:01fc53be672acae37e611c80cc0b4f3939584de3</id>
<content type='text'>
commit 2f4a4d63a193be6fd530d180bb13c3592052904c upstream.

To align with ACPI 6.3+, since bit_width can be any 8-bit value, it
cannot be depended on to be always on a clean 8b boundary. This was
uncovered on the Cobalt 100 platform.

SError Interrupt on CPU26, code 0xbe000011 -- SError
 CPU: 26 PID: 1510 Comm: systemd-udevd Not tainted 5.15.2.1-13 #1
 Hardware name: MICROSOFT CORPORATION, BIOS MICROSOFT CORPORATION
 pstate: 62400009 (nZCv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
 pc : cppc_get_perf_caps+0xec/0x410
 lr : cppc_get_perf_caps+0xe8/0x410
 sp : ffff8000155ab730
 x29: ffff8000155ab730 x28: ffff0080139d0038 x27: ffff0080139d0078
 x26: 0000000000000000 x25: ffff0080139d0058 x24: 00000000ffffffff
 x23: ffff0080139d0298 x22: ffff0080139d0278 x21: 0000000000000000
 x20: ffff00802b251910 x19: ffff0080139d0000 x18: ffffffffffffffff
 x17: 0000000000000000 x16: ffffdc7e111bad04 x15: ffff00802b251008
 x14: ffffffffffffffff x13: ffff013f1fd63300 x12: 0000000000000006
 x11: ffffdc7e128f4420 x10: 0000000000000000 x9 : ffffdc7e111badec
 x8 : ffff00802b251980 x7 : 0000000000000000 x6 : ffff0080139d0028
 x5 : 0000000000000000 x4 : ffff0080139d0018 x3 : 00000000ffffffff
 x2 : 0000000000000008 x1 : ffff8000155ab7a0 x0 : 0000000000000000
 Kernel panic - not syncing: Asynchronous SError Interrupt
 CPU: 26 PID: 1510 Comm: systemd-udevd Not tainted
5.15.2.1-13 #1
 Hardware name: MICROSOFT CORPORATION, BIOS MICROSOFT CORPORATION
 Call trace:
  dump_backtrace+0x0/0x1e0
  show_stack+0x24/0x30
  dump_stack_lvl+0x8c/0xb8
  dump_stack+0x18/0x34
  panic+0x16c/0x384
  add_taint+0x0/0xc0
  arm64_serror_panic+0x7c/0x90
  arm64_is_fatal_ras_serror+0x34/0xa4
  do_serror+0x50/0x6c
  el1h_64_error_handler+0x40/0x74
  el1h_64_error+0x7c/0x80
  cppc_get_perf_caps+0xec/0x410
  cppc_cpufreq_cpu_init+0x74/0x400 [cppc_cpufreq]
  cpufreq_online+0x2dc/0xa30
  cpufreq_add_dev+0xc0/0xd4
  subsys_interface_register+0x134/0x14c
  cpufreq_register_driver+0x1b0/0x354
  cppc_cpufreq_init+0x1a8/0x1000 [cppc_cpufreq]
  do_one_initcall+0x50/0x250
  do_init_module+0x60/0x27c
  load_module+0x2300/0x2570
  __do_sys_finit_module+0xa8/0x114
  __arm64_sys_finit_module+0x2c/0x3c
  invoke_syscall+0x78/0x100
  el0_svc_common.constprop.0+0x180/0x1a0
  do_el0_svc+0x84/0xa0
  el0_svc+0x2c/0xc0
  el0t_64_sync_handler+0xa4/0x12c
  el0t_64_sync+0x1a4/0x1a8

Instead, use access_width to determine the size and use the offset and
width to shift and mask the bits to read/write out. Make sure to add a
check for system memory since pcc redefines the access_width to
subspace id.

If access_width is not set, then fall back to using bit_width.

Signed-off-by: Jarred White &lt;jarredwhite@linux.microsoft.com&gt;
Reviewed-by: Easwar Hariharan &lt;eahariha@linux.microsoft.com&gt;
Cc: 5.15+ &lt;stable@vger.kernel.org&gt; # 5.15+
[ rjw: Subject and changelog edits, comment adjustments ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Disable FIE if registers in PCC regions</title>
<updated>2022-09-24T16:43:46+00:00</updated>
<author>
<name>Jeremy Linton</name>
<email>jeremy.linton@arm.com</email>
</author>
<published>2022-09-12T20:37:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ae2df912d1a557a3548be83da20851ac55f42ab3'/>
<id>urn:sha1:ae2df912d1a557a3548be83da20851ac55f42ab3</id>
<content type='text'>
PCC regions utilize a mailbox to set/retrieve register values used by
the CPPC code. This is fine as long as the operations are
infrequent. With the FIE code enabled though the overhead can range
from 2-11% of system CPU overhead (ex: as measured by top) on Arm
based machines.

So, before enabling FIE assure none of the registers used by
cppc_get_perf_ctrs() are in the PCC region. Finally, add a module
parameter which can override the PCC region detection at boot or
module reload.

Signed-off-by: Jeremy Linton &lt;jeremy.linton@arm.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Reviewed-by: Ionela Voinescu &lt;ionela.voinescu@arm.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI: CPPC: Add ACPI disabled check to acpi_cpc_valid()</title>
<updated>2022-08-25T11:55:17+00:00</updated>
<author>
<name>Perry Yuan</name>
<email>Perry.Yuan@amd.com</email>
</author>
<published>2022-08-14T16:35:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=a2a9d1850060e5d995136561d76e81d61414f076'/>
<id>urn:sha1:a2a9d1850060e5d995136561d76e81d61414f076</id>
<content type='text'>
Make acpi_cpc_valid() check if ACPI is disabled, so that its callers
don't need to check that separately.  This will also cause the AMD
pstate driver to refuse to load right away when ACPI is disabled.

Also update the warning message in amd_pstate_init() to mention the
ACPI disabled case for completeness.

Signed-off-by: Perry Yuan &lt;Perry.Yuan@amd.com&gt;
[ rjw: Subject edits, new changelog ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
</feed>
