kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-11-10 20:48:12 +00:00
Code Issues Releases Packages Activity
No description
1,313,174 commits 117 branches 5,827 tags 6.3 GiB
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Wei Fang 45ece2a4e3 net: phy: micrel: Dynamically control external clock of KSZ PHY 
[ Upstream commit 25c6a5ab15 ]

On the i.MX6ULL-14x14-EVK board, enet1_ref and enet2_ref are used as the
clock sources for two external KSZ PHYs. However, after closing the two
FEC ports, the clk_enable_count of the enet1_ref and enet2_ref clocks is
not 0. The root cause is that since the commit 9853294627 ("net: phy:
micrel: use devm_clk_get_optional_enabled for the rmii-ref clock"), the
external clock of KSZ PHY has been enabled when the PHY driver probes,
and it can only be disabled when the PHY driver is removed. This causes
the clock to continue working when the system is suspended or the network
port is down.

Although Heiko explained in the commit message that the patch was because
some clock suppliers need to enable the clock to get the valid clock rate
, it seems that the simple fix is to disable the clock after getting the
clock rate to solve the current problem. This is indeed true, but we need
to admit that Heiko's patch has been applied for more than a year, and we
cannot guarantee whether there are platforms that only enable rmii-ref in
the KSZ PHY driver during this period. If this is the case, disabling
rmii-ref will cause RMII on these platforms to not work.

Secondly, commit 99ac4cbcc2 ("net: phy: micrel: allow usage of generic
ethernet-phy clock") just simply enables the generic clock permanently,
which seems like the generic clock may only be enabled in the PHY driver.
If we simply disable the generic clock, RMII may not work. If we keep it
as it is, the platform using the generic clock will have the same problem
as the i.MX6ULL platform.

To solve this problem, the clock is enabled when phy_driver::resume() is
called, and the clock is disabled when phy_driver::suspend() is called.
Since phy_driver::resume() and phy_driver::suspend() are not called in
pairs, an additional clk_enable flag is added. When phy_driver::suspend()
is called, the clock is disabled only if clk_enable is true. Conversely,
when phy_driver::resume() is called, the clock is enabled if clk_enable
is false.

The changes that introduced the problem were only a few lines, while the
current fix is about a hundred lines, which seems out of proportion, but
it is necessary because kszphy_probe() is used by multiple KSZ PHYs and
we need to fix all of them.

Fixes: 9853294627 ("net: phy: micrel: use devm_clk_get_optional_enabled for the rmii-ref clock")
Fixes: 99ac4cbcc2 ("net: phy: micrel: allow usage of generic ethernet-phy clock")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20241217063500.1424011-1-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2025-01-09 13:33:36 +01:00
arch perf/x86/intel/ds: Add PEBS format 6 2025-01-02 10:34:23 +01:00
block block: lift bio_is_zone_append to bio.h 2025-01-09 13:33:32 +01:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: ecdsa - Avoid signed integer overflow on signature decoding 2024-12-14 20:03:36 +01:00
Documentation platform/x86: thinkpad-acpi: Add support for hotkey 0x1401 2025-01-09 13:33:31 +01:00
drivers net: phy: micrel: Dynamically control external clock of KSZ PHY 2025-01-09 13:33:36 +01:00
fs btrfs: use bio_is_zone_append() in the completion handler 2025-01-09 13:33:33 +01:00
include RDMA/mlx5: Enforce same type port association for multiport RoCE 2025-01-09 13:33:33 +01:00
init Compiler Attributes: disable __counted_by for clang < 19.1.3 2024-12-05 14:02:45 +01:00
io_uring io_uring/sqpoll: fix sqpoll error handling races 2025-01-02 10:34:22 +01:00
ipc ipc: fix memleak if msg_init_ns failed in create_ipc_ns 2024-12-05 14:03:02 +01:00
kernel tracing: Have process_string() also allow arrays 2025-01-09 13:33:32 +01:00
lib timekeeping: Remove CONFIG_DEBUG_TIMEKEEPING 2024-12-14 20:04:16 +01:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm mm: convert partially_mapped set/clear operations to be atomic 2024-12-27 14:02:20 +01:00
net bpf: Check negative offsets in __bpf_skb_min_len() 2025-01-02 10:34:11 +01:00
rust rust: kbuild: set bindgen's Rust target version 2024-12-19 18:13:22 +01:00
samples samples/bpf: Fix a resource leak 2024-12-14 20:03:46 +01:00
scripts setlocalversion: work around "git describe" performance 2024-12-14 20:04:10 +01:00
security selinux: ignore unknown extended permissions 2025-01-09 13:33:32 +01:00
sound ALSA: sh: Fix wrong argument order for copy_from_iter() 2025-01-02 10:34:26 +01:00
tools sched_ext: fix application of sizeof to pointer 2025-01-09 13:33:33 +01:00
usr initramfs: shorten cmd_initfs in usr/Makefile 2024-07-16 01:07:52 +09:00
virt KVM: x86: switch hugepage recovery thread to vhost_task 2024-12-05 14:02:43 +01:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore Add Jeff Kirsher to .get_maintainer.ignore 2024-03-08 11:36:54 +00:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.12 2024-09-24 13:02:06 -07:00
.mailmap mailmap: add entry for Thorsten Blum 2024-11-07 14:14:59 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove self from DSA entry 2024-11-03 12:52:38 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MAINTAINERS: update location of media main tree 2024-12-05 14:02:42 +01:00
Makefile Linux 6.12.8 2025-01-02 10:34:26 +01:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.