[PATCH v2 0/3] clk: ti: dpll: switch spread spectrum to the generic framework

[PATCH v2 0/3] clk: ti: dpll: switch spread spectrum to the generic framework

[Dario Binacchi]

The am33xx/am43xx DPLL spread spectrum clocking (SSC) is configured
through vendor specific DT properties. Since 7.3 the clock framework
provides a generic API and the assigned-clock-sscs DT property for it,
so the series moves the TI DPLL to the generic configuration and drops
the vendor specific properties.

The last patch applies the configuration right away, as the clock
core skips set_rate() when the requested rate is already the current
one, e.g. when the bootloader has set it up.

Tested on a BeagleBone Black with equivalent parameters. The
dpll_disp_ck SSC registers are programmed with the same values as with
the vendor specific properties.

Changes in v2:
- Check the DPLL lock state instead of its parent, as the reference
  and bypass clocks can be the same clock

Dario Binacchi (3):
  dt-bindings: clock: ti: dpll: drop the ti,ssc-* properties
  clk: ti: dpll: use the generic spread spectrum configuration
  clk: ti: dpll: apply the spread spectrum configuration right away

 .../devicetree/bindings/clock/ti/dpll.txt     |  6 --
 drivers/clk/ti/clock.h                        |  2 +
 drivers/clk/ti/dpll.c                         |  8 +-
 drivers/clk/ti/dpll3xxx.c                     | 95 +++++++++++++++++--
 include/linux/clk/ti.h                        |  9 +-
 5 files changed, 91 insertions(+), 29 deletions(-)

---
base-commit: 6b4b543fa18757297ac756a6fe6e64f506b7844a
branch: am33xx-assigned-clock-sscs

-- 
2.43.0

[PATCH v2 1/3] dt-bindings: clock: ti: dpll: drop the ti,ssc-* properties

[Dario Binacchi]

The common clock binding provides assigned-clock-sscs to configure
spread spectrum clocking (SSC), supported by the clock core since commit
a7f16660af39 ("clk: conf: Support assigned-clock-sscs"). Keeping the
vendor specific ti,ssc-deltam, ti,ssc-modfreq-hz and ti,ssc-downspread
properties would leave two ways to describe the same thing.

The properties have no in-tree users, so they can be dropped.

Existing DTS files using them continue to work, with SSC disabled,
until they switch to assigned-clock-sscs.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>

---
If keeping the properties as deprecated is preferred, I can add a
fallback to the driver in v2.

(no changes since v1)

 Documentation/devicetree/bindings/clock/ti/dpll.txt | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/Documentation/devicetree/bindings/clock/ti/dpll.txt b/Documentation/devicetree/bindings/clock/ti/dpll.txt
index 14a1b72c2e71..ffbe50f46e68 100644
--- a/Documentation/devicetree/bindings/clock/ti/dpll.txt
+++ b/Documentation/devicetree/bindings/clock/ti/dpll.txt
@@ -56,12 +56,6 @@ Optional properties:
 	- ti,lock : DPLL locks in programmed rate
 	- ti,min-div : the minimum divisor to start from to round the DPLL
 		       target rate
-	- ti,ssc-deltam : DPLL supports spread spectrum clocking, frequency
-			  spreading in permille (10th of a percent)
-	- ti,ssc-modfreq-hz : DPLL supports spread spectrum clocking, spread
-			      spectrum modulation frequency
-	- ti,ssc-downspread : DPLL supports spread spectrum clocking, boolean
-			      to enable the downspread feature
 
 Examples:
 	dpll_core_ck: dpll_core_ck@44e00490 {
-- 
2.43.0

Re: [PATCH v2 1/3] dt-bindings: clock: ti: dpll: drop the ti,ssc-* properties

[Krzysztof Kozlowski]

On 26/10/2026 08:46, Dario Binacchi wrote:
> The common clock binding provides assigned-clock-sscs to configure
> spread spectrum clocking (SSC), supported by the clock core since commit
> a7f16660af39 ("clk: conf: Support assigned-clock-sscs"). Keeping the
> vendor specific ti,ssc-deltam, ti,ssc-modfreq-hz and ti,ssc-downspread
> properties would leave two ways to describe the same thing.
> 
> The properties have no in-tree users, so they can be dropped.
> 
> Existing DTS files using them continue to work, with SSC disabled,
> until they switch to assigned-clock-sscs.
> 
> Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> 
> ---
> If keeping the properties as deprecated is preferred, I can add a
> fallback to the driver in v2.
> 
> (no changes since v1)
> 

I responded under v1, so same here:

I see the user:
	git grep ti,ssc-deltam

Maybe you ordered patches incorrectly. Anyway, properties with in-tree
users must be documented, so make them deprecated instead.

Best regards,
Krzysztof