[v4,00/68] clk: Make determine_rate mandatory for muxes

Message

Maxime Ripard May 5, 2023, 11:25 a.m. UTC

Hi,

This is a follow-up to a previous series that was printing a warning
when a mux has a set_parent implementation but is missing
determine_rate().

The rationale is that set_parent() is very likely to be useful when
changing the rate, but it's determine_rate() that takes the parenting
decision. If we're missing it, then the current parent is always going
to be used, and thus set_parent() will not be used. The only exception
being a direct call to clk_set_parent(), but those are fairly rare
compared to clk_set_rate().

Stephen then asked to promote the warning to an error, and to fix up all
the muxes that are in that situation first. So here it is :)

It was build-tested on x86, arm and arm64.

Affected drivers have been tracked down by the following coccinelle
script:

virtual report 

@ clk_ops @
identifier ops;
position p;
@@

 struct clk_ops ops@p = {
   ...
 };

@ has_set_parent @
identifier clk_ops.ops;
identifier set_parent_f;
@@

  struct clk_ops ops = {
	.set_parent = set_parent_f,
  };

@ has_determine_rate @
identifier clk_ops.ops;
identifier determine_rate_f;
@@

  struct clk_ops ops = {
	.determine_rate = determine_rate_f,
  };

@ script:python depends on report && has_set_parent && !has_determine_rate @
ops << clk_ops.ops;
set_parent_f << has_set_parent.set_parent_f;
p << clk_ops.p;
@@

coccilib.report.print_report(p[0], "ERROR: %s has set_parent (%s)" % (ops, set_parent_f))

Berlin is the only user still matching after this series has been
applied, but it's because it uses a composite clock which throws the
script off. The driver has been converted and shouldn't be a problem. 

Let me know what you think,
Maxime

Signed-off-by: Maxime Ripard <[e-mail]>
---
Changes in v4:
- Switch from __clk_mux_determine_rate to a new helper
- Introduced unit tests for that new helper
- Fix kunit regression
- Reworded most of the commit logs
- Link to v3: https://lore.kernel.org/r/[e-mail]

Changes in v3:
- Rebased on top of next-20230404
- Link to v2: https://lore.kernel.org/r/[e-mail]

Changes in v2:
- Drop all the patches already applied
- Promote the clk registration warning to an error
- Make all muxes use determine_rate
- Link to v1: https://lore.kernel.org/r/[e-mail]

---
Maxime Ripard (66):
      clk: Export clk_hw_forward_rate_request()
      clk: test: Fix type sign of rounded rate variables
      clk: lan966x: Remove unused round_rate hook
      clk: nodrv: Add a determine_rate hook
      clk: test: Add a determine_rate hook
      clk: actions: composite: Add a determine_rate hook for pass clk
      clk: at91: main: Add a determine_rate hook
      clk: at91: sckc: Add a determine_rate hook
      clk: berlin: div: Add a determine_rate hook
      clk: cdce706: Add a determine_rate hook
      clk: k210: pll: Add a determine_rate hook
      clk: k210: aclk: Add a determine_rate hook
      clk: k210: mux: Add a determine_rate hook
      clk: lmk04832: clkout: Add a determine_rate hook
      clk: lochnagar: Add a determine_rate hook
      clk: qoriq: Add a determine_rate hook
      clk: si5341: Add a determine_rate hook
      clk: stm32f4: mux: Add a determine_rate hook
      clk: vc5: mux: Add a determine_rate hook
      clk: vc5: clkout: Add a determine_rate hook
      clk: wm831x: clkout: Add a determine_rate hook
      clk: davinci: da8xx-cfgchip: Add a determine_rate hook
      clk: davinci: da8xx-cfgchip: Add a determine_rate hook
      clk: imx: busy: Add a determine_rate hook
      clk: imx: fixup-mux: Add a determine_rate hook
      clk: imx: scu: Add a determine_rate hook
      clk: mediatek: cpumux: Add a determine_rate hook
      clk: pxa: Add a determine_rate hook
      clk: renesas: r9a06g032: Add a determine_rate hook
      clk: socfpga: gate: Add a determine_rate hook
      clk: stm32: core: Add a determine_rate hook
      clk: tegra: bpmp: Add a determine_rate hook
      clk: tegra: super: Add a determine_rate hook
      clk: tegra: periph: Add a determine_rate hook
      clk: ux500: prcmu: Add a determine_rate hook
      clk: ux500: sysctrl: Add a determine_rate hook
      clk: versatile: sp810: Add a determine_rate hook
      drm/tegra: sor: Add a determine_rate hook
      phy: cadence: sierra: Add a determine_rate hook
      phy: cadence: torrent: Add a determine_rate hook
      phy: ti: am654-serdes: Add a determine_rate hook
      phy: ti: j721e-wiz: Add a determine_rate hook
      rtc: sun6i: Add a determine_rate hook
      ASoC: tlv320aic32x4: Add a determine_rate hook
      clk: actions: composite: div: Switch to determine_rate
      clk: actions: composite: fact: Switch to determine_rate
      clk: at91: smd: Switch to determine_rate
      clk: axi-clkgen: Switch to determine_rate
      clk: cdce706: divider: Switch to determine_rate
      clk: cdce706: clkout: Switch to determine_rate
      clk: si5341: Switch to determine_rate
      clk: si5351: pll: Switch to determine_rate
      clk: si5351: msynth: Switch to determine_rate
      clk: si5351: clkout: Switch to determine_rate
      clk: da8xx: clk48: Switch to determine_rate
      clk: imx: scu: Switch to determine_rate
      clk: ingenic: cgu: Switch to determine_rate
      clk: ingenic: tcu: Switch to determine_rate
      clk: sprd: composite: Switch to determine_rate
      clk: st: flexgen: Switch to determine_rate
      clk: stm32: composite: Switch to determine_rate
      clk: tegra: periph: Switch to determine_rate
      clk: tegra: super: Switch to determine_rate
      ASoC: tlv320aic32x4: pll: Switch to determine_rate
      ASoC: tlv320aic32x4: div: Switch to determine_rate
      clk: Forbid to register a mux without determine_rate

Stephen Boyd (2):
      clk: Move no reparent case into a separate function
      clk: Introduce clk_hw_determine_rate_no_reparent()

 drivers/clk/actions/owl-composite.c       |  35 ++++--
 drivers/clk/at91/clk-main.c               |   1 +
 drivers/clk/at91/clk-smd.c                |  29 +++--
 drivers/clk/at91/sckc.c                   |   1 +
 drivers/clk/berlin/berlin2-div.c          |   1 +
 drivers/clk/clk-axi-clkgen.c              |  14 ++-
 drivers/clk/clk-cdce706.c                 |  30 ++---
 drivers/clk/clk-k210.c                    |   3 +
 drivers/clk/clk-lan966x.c                 |  17 ---
 drivers/clk/clk-lmk04832.c                |   1 +
 drivers/clk/clk-lochnagar.c               |   1 +
 drivers/clk/clk-qoriq.c                   |   1 +
 drivers/clk/clk-si5341.c                  |  19 ++--
 drivers/clk/clk-si5351.c                  |  67 ++++++-----
 drivers/clk/clk-stm32f4.c                 |   1 +
 drivers/clk/clk-versaclock5.c             |   2 +
 drivers/clk/clk-wm831x.c                  |   1 +
 drivers/clk/clk.c                         | 108 ++++++++++++------
 drivers/clk/clk_test.c                    | 180 +++++++++++++++++++++++++++++-
 drivers/clk/davinci/da8xx-cfgchip.c       |  12 +-
 drivers/clk/imx/clk-busy.c                |   1 +
 drivers/clk/imx/clk-fixup-mux.c           |   1 +
 drivers/clk/imx/clk-scu.c                 |  20 +++-
 drivers/clk/ingenic/cgu.c                 |  15 +--
 drivers/clk/ingenic/tcu.c                 |  19 ++--
 drivers/clk/mediatek/clk-cpumux.c         |   1 +
 drivers/clk/pxa/clk-pxa.c                 |   1 +
 drivers/clk/renesas/r9a06g032-clocks.c    |   1 +
 drivers/clk/socfpga/clk-gate.c            |   1 +
 drivers/clk/sprd/composite.c              |  16 ++-
 drivers/clk/st/clk-flexgen.c              |  15 +--
 drivers/clk/stm32/clk-stm32-core.c        |  33 ++++--
 drivers/clk/tegra/clk-bpmp.c              |   1 +
 drivers/clk/tegra/clk-periph.c            |  17 ++-
 drivers/clk/tegra/clk-super.c             |  16 ++-
 drivers/clk/ux500/clk-prcmu.c             |   1 +
 drivers/clk/ux500/clk-sysctrl.c           |   1 +
 drivers/clk/versatile/clk-sp810.c         |   1 +
 drivers/gpu/drm/tegra/sor.c               |   1 +
 drivers/phy/cadence/phy-cadence-sierra.c  |   1 +
 drivers/phy/cadence/phy-cadence-torrent.c |   1 +
 drivers/phy/ti/phy-am654-serdes.c         |   1 +
 drivers/phy/ti/phy-j721e-wiz.c            |   1 +
 drivers/rtc/rtc-sun6i.c                   |   1 +
 include/linux/clk-provider.h              |   2 +
 sound/soc/codecs/tlv320aic32x4-clk.c      |  33 +++---
 46 files changed, 527 insertions(+), 199 deletions(-)
---
base-commit: 145e5cddfe8b4bf607510b2dcf630d95f4db420f
change-id: 20221018-clk-range-checks-fixes-2039f3523240

Best regards,

Comments

Stephen Boyd June 9, 2023, 1:49 a.m. UTC | #1

Quoting Maxime Ripard (2023-05-05 04:25:02)
> Hi,
> 
> This is a follow-up to a previous series that was printing a warning
> when a mux has a set_parent implementation but is missing
> determine_rate().
> 
> The rationale is that set_parent() is very likely to be useful when
> changing the rate, but it's determine_rate() that takes the parenting
> decision. If we're missing it, then the current parent is always going
> to be used, and thus set_parent() will not be used. The only exception
> being a direct call to clk_set_parent(), but those are fairly rare
> compared to clk_set_rate().
> 
> Stephen then asked to promote the warning to an error, and to fix up all
> the muxes that are in that situation first. So here it is :)
> 

I've applied this to clk-next after squashing in an export. Thanks for
taking this on.

I'll have to monitor for wreckage with any in-flight drivers. I suspect
I'll have to take out the last commit, but maybe we can just let those
in-flight drivers get fixed up later.