Re: [PATCH v3 3/3] clk: samsung: exynos990: Fix PERIS gate clock parents

Re: [PATCH v3 3/3] clk: samsung: exynos990: Fix PERIS gate clock parents

[Denzeel Oliva]

On Sat, Jun 13, 2026, Sashiko AI wrote:
> Does reordering the mout_peris_clk_peris_gic_p array break the hardware
> register mapping?
>
> In the Exynos clock framework, the indices of the PNAME array correspond
> directly to the hardware multiplexer register bit values...

The reorder does not break the mapping — it corrects it. The original
upstream PNAME order was a porting bug that inverted the parents.

The downstream Exynos9830 source confirms the hardware register encoding
(drivers/soc/samsung/cal-if/exynos9830/cmucal-node.c:1093-1096):

  enum clk_id cmucal_mux_clk_peris_gic_parents[] = {
      MUX_CLKCMU_PERIS_BUS_USER,   // index 0 → mux value 0
      OSCCLK_PERIS,                 // index 1 → mux value 1
  };

So hardware mux value 0 selects MUX_CLKCMU_PERIS_BUS_USER (upstream:
mout_peris_bus_user), not oscclk. The original upstream had these
swapped, which would cause clk_set_parent() to write the wrong mux
register value.

This patch fixes that inversion.

[PATCH v3 0/3] clk: samsung: exynos990: Fix PERIS gate clock parents and add TMU_SUB

[Denzeel Oliva]

Fix several PERIS CMU clock parent mismatches and add the missing
TMU_SUB_PCLK gate clock.  The dt-bindings patch adds the new clock
ID.  The second patch adds the TMU_SUB_PCLK gate.  The third patch
corrects eight gate clock parents and reorders the GIC mux parents.

Signed-off-by: Denzeel Oliva <wachiturroxd150@gmail.com>
---
v2 -> v3:
  - Split TMU_SUB gate addition from parent fixes into separate
    patches (Krzysztof)
  - Now three patches: dt-bindings, add gate, fix parents

v2: https://lore.kernel.org/r/20260613-exynos990-peris-fix-v2-v2-0-3dff7ade75b3@gmail.com
v1: https://lore.kernel.org/r/20260528-exynos990-peris-fix-v1-1-5b65aa7def2d@gmail.com

---
Denzeel Oliva (3):
      dt-bindings: clock: exynos990: Add CLK_GOUT_PERIS_TMU_SUB_PCLK
      clk: samsung: exynos990: Add PERIS TMU_SUB_PCLK gate
      clk: samsung: exynos990: Fix PERIS gate clock parents

 drivers/clk/samsung/clk-exynos990.c           | 24 ++++++++++++++----------
 include/dt-bindings/clock/samsung,exynos990.h |  1 +
 2 files changed, 15 insertions(+), 10 deletions(-)
---
base-commit: c425609d6ac4012c8bbf01ec2e10e801b1923a7b
change-id: 20260613-exynos990-peris-fix-v3-fac19b879206

Best regards,
--  
Denzeel Oliva <wachiturroxd150@gmail.com>

[PATCH v3 3/3] clk: samsung: exynos990: Fix PERIS gate clock parents

[Denzeel Oliva]

Correct eight PERIS gate clock parents to match the hardware clock
tree and reorder the GIC mux parents so mout_peris_bus_user is the
default source.

Signed-off-by: Denzeel Oliva <wachiturroxd150@gmail.com>
---
 drivers/clk/samsung/clk-exynos990.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos990.c b/drivers/clk/samsung/clk-exynos990.c
index ee3566b8e57c..df5928833b23 100644
--- a/drivers/clk/samsung/clk-exynos990.c
+++ b/drivers/clk/samsung/clk-exynos990.c
@@ -2551,7 +2551,7 @@ static const unsigned long peris_clk_regs[] __initconst = {
 
 /* Parent clock list for CMU_PERIS muxes */
 PNAME(mout_peris_bus_user_p)		= { "oscclk", "mout_cmu_peris_bus" };
-PNAME(mout_peris_clk_peris_gic_p)	= { "oscclk", "mout_peris_bus_user" };
+PNAME(mout_peris_clk_peris_gic_p)	= { "mout_peris_bus_user", "oscclk" };
 
 static const struct samsung_mux_clock peris_mux_clks[] __initconst = {
 	MUX(CLK_MOUT_PERIS_BUS_USER, "mout_peris_bus_user",
@@ -2584,15 +2584,15 @@ static const struct samsung_gate_clock peris_gate_clks[] __initconst = {
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_RSTNSYNC_CLK_PERIS_BUSP_IPCLKPORT_CLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_CLK_PERIS_OSCCLK_CLK,
-	     "gout_peris_clk_peris_oscclk_clk", "mout_peris_bus_user",
+	     "gout_peris_clk_peris_oscclk_clk", "oscclk",
 	     CLK_CON_GAT_CLK_BLK_PERIS_UID_RSTNSYNC_CLK_PERIS_OSCCLK_IPCLKPORT_CLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_CLK_PERIS_GIC_CLK,
-	     "gout_peris_clk_peris_gic_clk", "mout_peris_bus_user",
+	     "gout_peris_clk_peris_gic_clk", "mout_peris_clk_peris_gic",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_RSTNSYNC_CLK_PERIS_GIC_IPCLKPORT_CLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_AD_AXI_P_PERIS_ACLKM,
-	     "gout_peris_ad_axi_p_peris_aclkm", "mout_peris_bus_user",
+	     "gout_peris_ad_axi_p_peris_aclkm", "mout_peris_clk_peris_gic",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_AD_AXI_P_PERIS_IPCLKPORT_ACLKM,
 	     21, CLK_IGNORE_UNUSED, 0),
 	GATE(CLK_GOUT_PERIS_OTP_CON_BIRA_PCLK,
@@ -2600,19 +2600,19 @@ static const struct samsung_gate_clock peris_gate_clks[] __initconst = {
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_OTP_CON_BIRA_IPCLKPORT_PCLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_GIC_CLK,
-	     "gout_peris_gic_clk", "mout_peris_bus_user",
+	     "gout_peris_gic_clk", "mout_peris_clk_peris_gic",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_GIC_IPCLKPORT_CLK,
 	     21, CLK_IS_CRITICAL, 0),
 	GATE(CLK_GOUT_PERIS_LHM_AXI_P_PERIS_CLK,
-	     "gout_peris_lhm_axi_p_peris_clk", "oscclk",
+	     "gout_peris_lhm_axi_p_peris_clk", "mout_peris_bus_user",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_LHM_AXI_P_PERIS_IPCLKPORT_I_CLK,
 	     21, CLK_IGNORE_UNUSED, 0),
 	GATE(CLK_GOUT_PERIS_MCT_PCLK,
-	     "gout_peris_mct_pclk", "mout_peris_clk_peris_gic",
+	     "gout_peris_mct_pclk", "mout_peris_bus_user",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_MCT_IPCLKPORT_PCLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_OTP_CON_TOP_PCLK,
-	     "gout_peris_otp_con_top_pclk", "mout_peris_clk_peris_gic",
+	     "gout_peris_otp_con_top_pclk", "mout_peris_bus_user",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_OTP_CON_TOP_IPCLKPORT_PCLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_D_TZPC_PERIS_PCLK,
@@ -2624,7 +2624,7 @@ static const struct samsung_gate_clock peris_gate_clks[] __initconst = {
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_TMU_SUB_IPCLKPORT_PCLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_TMU_TOP_PCLK,
-	     "gout_peris_tmu_top_pclk", "mout_peris_clk_peris_gic",
+	     "gout_peris_tmu_top_pclk", "mout_peris_bus_user",
 	     CLK_CON_GAT_GOUT_BLK_PERIS_UID_TMU_TOP_IPCLKPORT_PCLK,
 	     21, 0, 0),
 	GATE(CLK_GOUT_PERIS_OTP_CON_BIRA_OSCCLK,

-- 
2.54.0

Re: [PATCH v3 3/3] clk: samsung: exynos990: Fix PERIS gate clock parents

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Reordering a clock parent array (PNAME) to change the default clock parent falsifies the hardware register mapping.
--

commit 053886a8fb5adfd1285c3768f792e89fdc6baa21
Author: Denzeel Oliva <wachiturroxd150@gmail.com>

clk: samsung: exynos990: Fix PERIS gate clock parents

This commit corrects eight PERIS gate clock parents to match the hardware
clock tree. It also reorders the GIC mux parents to make mout_peris_bus_user
the default source.

> diff --git a/drivers/clk/samsung/clk-exynos990.c b/drivers/clk/samsung/clk-exynos990.c
> index ee3566b8e57c9..df5928833b232 100644
> --- a/drivers/clk/samsung/clk-exynos990.c
> +++ b/drivers/clk/samsung/clk-exynos990.c
> @@ -2551,7 +2551,7 @@ static const unsigned long peris_clk_regs[] __initconst = {
>  
>  /* Parent clock list for CMU_PERIS muxes */
>  PNAME(mout_peris_bus_user_p)		= { "oscclk", "mout_cmu_peris_bus" };
> -PNAME(mout_peris_clk_peris_gic_p)	= { "oscclk", "mout_peris_bus_user" };
> +PNAME(mout_peris_clk_peris_gic_p)	= { "mout_peris_bus_user", "oscclk" };

[Severity: High]
Does reordering the mout_peris_clk_peris_gic_p array break the hardware
register mapping?

In the Exynos clock framework, the indices of the PNAME array correspond
directly to the hardware multiplexer register bit values (where index 0 maps
to register value 0). Reordering the array to change the default parent could
cause the framework to write the wrong index to the mux register when
clk_set_parent() is called.

Should the default clock parent be configured using the assigned-clocks and
assigned-clock-parents properties in the Device Tree instead of modifying the
driver's hardware description?

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260613-exynos990-peris-fix-v3-v3-0-2b230db78ae4@gmail.com?part=3