[PATCH v3 0/4] clk: thead: Changes to TH1520 clock driver for disp

[PATCH v3 0/4] clk: thead: Changes to TH1520 clock driver for disp

[Icenowy Zheng]

This patchset is my changes to the TH1520 clock driver, mainly for
supporting the display controller.

The first patch is previously a dependency of this patchset before v3,
but a rebase operation in v3 changed it and it's now pulled into this
patchset.

The 2nd and 3rd ones are functionality additions, with the first one
adding support for enabling/disabling PLLs (for DPU PLL) and the second
one adding support for changing DPU dividers.

The 4th one is to address hang issues met when testing the DPU driver
w/o clk_ignore_unused command line option.

The patchset is rebased atop the padctrl0 parent fix patchset (which
contains refactor of ccu_gate) at [1] in v3.

[1] https://lore.kernel.org/linux-riscv/20250816084445.2582692-1-uwu@icenowy.me/

Icenowy Zheng (3):
  clk: thead: add support for enabling/disabling PLLs
  clk: thead: support changing DPU pixel clock rate
  clk: thead: th1520-ap: set all AXI clocks to CLK_IS_CRITICAL

Michal Wilczynski (1):
  clk: thead: Correct parent for DPU pixel clocks

 drivers/clk/thead/clk-th1520-ap.c | 153 +++++++++++++++++++++++-------
 1 file changed, 121 insertions(+), 32 deletions(-)

-- 
2.50.1

[PATCH v3 1/4] clk: thead: Correct parent for DPU pixel clocks

[Icenowy Zheng]

From: Michal Wilczynski <m.wilczynski@samsung.com>

The dpu0_pixelclk and dpu1_pixelclk gates were incorrectly parented to
the video_pll_clk.

According to the TH1520 TRM, the "dpu0_pixelclk" should be sourced from
"DPU0 PLL DIV CLK". In this driver, "DPU0 PLL DIV CLK" corresponds to
the `dpu0_clk` clock, which is a divider whose parent is the
`dpu0_pll_clk`.

This patch corrects the clock hierarchy by reparenting `dpu0_pixelclk`
to `dpu0_clk`. By symmetry, `dpu1_pixelclk` is also reparented to its
correct source, `dpu1_clk`.

Fixes: 50d4b157fa96 ("clk: thead: Add clock support for VO subsystem in T-HEAD TH1520 SoC")
Reported-by: Icenowy Zheng <uwu@icenowy.me>
Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
[Icenowy: add Drew's R-b and rebased atop ccu_gate refactor]
Reviewed-by: Drew Fustini <fustini@kernel.org>
Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
---
Pulled into this patchset in v3 because of rebasing.

 drivers/clk/thead/clk-th1520-ap.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/thead/clk-th1520-ap.c b/drivers/clk/thead/clk-th1520-ap.c
index 8a5d699638379..ec52726fbea95 100644
--- a/drivers/clk/thead/clk-th1520-ap.c
+++ b/drivers/clk/thead/clk-th1520-ap.c
@@ -761,6 +761,10 @@ static struct ccu_div dpu0_clk = {
 	},
 };
 
+static const struct clk_parent_data dpu0_clk_pd[] = {
+	{ .hw = &dpu0_clk.common.hw }
+};
+
 static struct ccu_div dpu1_clk = {
 	.div		= TH_CCU_DIV_FLAGS(0, 8, CLK_DIVIDER_ONE_BASED),
 	.common		= {
@@ -773,6 +777,10 @@ static struct ccu_div dpu1_clk = {
 	},
 };
 
+static const struct clk_parent_data dpu1_clk_pd[] = {
+	{ .hw = &dpu1_clk.common.hw }
+};
+
 static CLK_FIXED_FACTOR_HW(emmc_sdio_ref_clk, "emmc-sdio-ref",
 			   &video_pll_clk.common.hw, 4, 1, 0);
 
@@ -853,9 +861,9 @@ static CCU_GATE(CLK_GPU_CORE, gpu_core_clk, "gpu-core-clk", video_pll_clk_pd,
 static CCU_GATE(CLK_GPU_CFG_ACLK, gpu_cfg_aclk, "gpu-cfg-aclk",
 		video_pll_clk_pd, 0x0, 4, 0);
 static CCU_GATE(CLK_DPU_PIXELCLK0, dpu0_pixelclk, "dpu0-pixelclk",
-		video_pll_clk_pd, 0x0, 5, 0);
+		dpu0_clk_pd, 0x0, 5, 0);
 static CCU_GATE(CLK_DPU_PIXELCLK1, dpu1_pixelclk, "dpu1-pixelclk",
-		video_pll_clk_pd, 0x0, 6, 0);
+		dpu1_clk_pd, 0x0, 6, 0);
 static CCU_GATE(CLK_DPU_HCLK, dpu_hclk, "dpu-hclk", video_pll_clk_pd, 0x0,
 		7, 0);
 static CCU_GATE(CLK_DPU_ACLK, dpu_aclk, "dpu-aclk", video_pll_clk_pd, 0x0,
-- 
2.50.1

[PATCH v3 2/4] clk: thead: add support for enabling/disabling PLLs

[Icenowy Zheng]

The 2nd control word of T-Head TH1520 PLLs contains a bit to put the VCO
into reset state, which means disabling the PLL.

Some PLLs are put to disabled state by the bootloader, and the clock
driver should be able to enable them.

Add support for enabling/disabling PLLs. PLLs other than DPU ones are
set CLK_IS_CRITICAL to prevent killing the system -- they're meant to
drive CPU or system buses (even the GMAC/Video ones are driving arbitrary
buses).

Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Reviewed-by: Drew Fustini <fustini@kernel.org>
---
No changes in v2.
Changes in v3:
- Added Drew's R-b.

 drivers/clk/thead/clk-th1520-ap.c | 38 +++++++++++++++++++++++++++----
 1 file changed, 33 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/thead/clk-th1520-ap.c b/drivers/clk/thead/clk-th1520-ap.c
index ec52726fbea95..d81445e24a96a 100644
--- a/drivers/clk/thead/clk-th1520-ap.c
+++ b/drivers/clk/thead/clk-th1520-ap.c
@@ -18,6 +18,7 @@
 #define TH1520_PLL_FBDIV	GENMASK(19, 8)
 #define TH1520_PLL_REFDIV	GENMASK(5, 0)
 #define TH1520_PLL_BYPASS	BIT(30)
+#define TH1520_PLL_VCO_RST	BIT(29)
 #define TH1520_PLL_DSMPD	BIT(24)
 #define TH1520_PLL_FRAC		GENMASK(23, 0)
 #define TH1520_PLL_FRAC_BITS    24
@@ -236,6 +237,30 @@ static const struct clk_ops ccu_div_ops = {
 	.determine_rate	= clk_hw_determine_rate_no_reparent,
 };
 
+static void ccu_pll_disable(struct clk_hw *hw)
+{
+	struct ccu_pll *pll = hw_to_ccu_pll(hw);
+
+	regmap_set_bits(pll->common.map, pll->common.cfg1,
+			TH1520_PLL_VCO_RST);
+}
+
+static int ccu_pll_enable(struct clk_hw *hw)
+{
+	struct ccu_pll *pll = hw_to_ccu_pll(hw);
+
+	return regmap_clear_bits(pll->common.map, pll->common.cfg1,
+				 TH1520_PLL_VCO_RST);
+}
+
+static int ccu_pll_is_enabled(struct clk_hw *hw)
+{
+	struct ccu_pll *pll = hw_to_ccu_pll(hw);
+
+	return !regmap_test_bits(pll->common.map, pll->common.cfg1,
+				 TH1520_PLL_VCO_RST);
+}
+
 static unsigned long th1520_pll_vco_recalc_rate(struct clk_hw *hw,
 						unsigned long parent_rate)
 {
@@ -293,6 +318,9 @@ static unsigned long ccu_pll_recalc_rate(struct clk_hw *hw,
 }
 
 static const struct clk_ops clk_pll_ops = {
+	.disable	= ccu_pll_disable,
+	.enable		= ccu_pll_enable,
+	.is_enabled	= ccu_pll_is_enabled,
 	.recalc_rate	= ccu_pll_recalc_rate,
 };
 
@@ -308,7 +336,7 @@ static struct ccu_pll cpu_pll0_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("cpu-pll0",
 					      osc_24m_clk,
 					      &clk_pll_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -320,7 +348,7 @@ static struct ccu_pll cpu_pll1_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("cpu-pll1",
 					      osc_24m_clk,
 					      &clk_pll_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -332,7 +360,7 @@ static struct ccu_pll gmac_pll_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("gmac-pll",
 					      osc_24m_clk,
 					      &clk_pll_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -352,7 +380,7 @@ static struct ccu_pll video_pll_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("video-pll",
 					      osc_24m_clk,
 					      &clk_pll_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -404,7 +432,7 @@ static struct ccu_pll tee_pll_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("tee-pll",
 					      osc_24m_clk,
 					      &clk_pll_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
-- 
2.50.1

[PATCH v3 3/4] clk: thead: support changing DPU pixel clock rate

[Icenowy Zheng]

The DPU pixel clock rate corresponds to the required dot clock of the
display mode, so it needs to be tweakable.

Add support to change it, by adding generic divider setting code,
arming the code to the dpu0/dpu1 clocks, and setting the pixel clock
connected to the DPU (after a gate) to CLK_SET_RATE_PARENT to propagate
it to the dividers.

Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Reviewed-by: Drew Fustini <fustini@kernel.org>
---
Changes in v2:
- Dropped round_rate() because of deprecation.
- Changed the logic of determine_rate() to early return if the divider
  could be changed.
Changes in v3:
- Rebased atop ccu_gate refactor.
- Fixed alignment issue of ccu_div_set_rate()'s signature.
- Removed a meaningless assignment to curr_val in ccu_div_set_rate()
  because of being immediately overriden.
- Added Drew's R-b.

 drivers/clk/thead/clk-th1520-ap.c | 63 ++++++++++++++++++++++++++++---
 1 file changed, 58 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/thead/clk-th1520-ap.c b/drivers/clk/thead/clk-th1520-ap.c
index d81445e24a96a..54222b3219ccf 100644
--- a/drivers/clk/thead/clk-th1520-ap.c
+++ b/drivers/clk/thead/clk-th1520-ap.c
@@ -56,6 +56,7 @@ struct ccu_gate {
 
 struct ccu_div {
 	u32			enable;
+	u32			div_en;
 	struct ccu_div_internal	div;
 	struct ccu_internal	mux;
 	struct ccu_common	common;
@@ -192,6 +193,55 @@ static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
 	return rate;
 }
 
+static int ccu_div_determine_rate(struct clk_hw *hw,
+				  struct clk_rate_request *req)
+{
+	struct ccu_div *cd = hw_to_ccu_div(hw);
+	unsigned int val;
+
+	if (cd->div_en)
+		return divider_determine_rate(hw, req, NULL,
+					      cd->div.width, cd->div.flags);
+
+	regmap_read(cd->common.map, cd->common.cfg0, &val);
+	val = val >> cd->div.shift;
+	val &= GENMASK(cd->div.width - 1, 0);
+	return divider_ro_determine_rate(hw, req, NULL, cd->div.width,
+					 cd->div.flags, val);
+}
+
+static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
+			    unsigned long parent_rate)
+{
+	struct ccu_div *cd = hw_to_ccu_div(hw);
+	int val = divider_get_val(rate, parent_rate, NULL,
+				  cd->div.width, cd->div.flags);
+	unsigned int curr_val, reg_val;
+
+	if (val < 0)
+		return val;
+
+	regmap_read(cd->common.map, cd->common.cfg0, &reg_val);
+	curr_val = reg_val >> cd->div.shift;
+	curr_val &= GENMASK(cd->div.width - 1, 0);
+
+	if (!cd->div_en && curr_val != val)
+		return -EINVAL;
+
+	reg_val &= ~cd->div_en;
+	regmap_write(cd->common.map, cd->common.cfg0, reg_val);
+	udelay(1);
+
+	reg_val &= ~GENMASK(cd->div.width + cd->div.shift - 1, cd->div.shift);
+	reg_val |= val << cd->div.shift;
+	regmap_write(cd->common.map, cd->common.cfg0, reg_val);
+
+	reg_val |= cd->div_en;
+	regmap_write(cd->common.map, cd->common.cfg0, reg_val);
+
+	return 0;
+}
+
 static u8 ccu_div_get_parent(struct clk_hw *hw)
 {
 	struct ccu_div *cd = hw_to_ccu_div(hw);
@@ -234,7 +284,8 @@ static const struct clk_ops ccu_div_ops = {
 	.get_parent	= ccu_div_get_parent,
 	.set_parent	= ccu_div_set_parent,
 	.recalc_rate	= ccu_div_recalc_rate,
-	.determine_rate	= clk_hw_determine_rate_no_reparent,
+	.set_rate	= ccu_div_set_rate,
+	.determine_rate = ccu_div_determine_rate,
 };
 
 static void ccu_pll_disable(struct clk_hw *hw)
@@ -778,6 +829,7 @@ static struct ccu_div venc_clk = {
 };
 
 static struct ccu_div dpu0_clk = {
+	.div_en		= BIT(8),
 	.div		= TH_CCU_DIV_FLAGS(0, 8, CLK_DIVIDER_ONE_BASED),
 	.common		= {
 		.clkid          = CLK_DPU0,
@@ -785,7 +837,7 @@ static struct ccu_div dpu0_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_HW("dpu0",
 					      dpu0_pll_clk_parent,
 					      &ccu_div_ops,
-					      0),
+					      CLK_SET_RATE_UNGATE),
 	},
 };
 
@@ -794,6 +846,7 @@ static const struct clk_parent_data dpu0_clk_pd[] = {
 };
 
 static struct ccu_div dpu1_clk = {
+	.div_en		= BIT(8),
 	.div		= TH_CCU_DIV_FLAGS(0, 8, CLK_DIVIDER_ONE_BASED),
 	.common		= {
 		.clkid          = CLK_DPU1,
@@ -801,7 +854,7 @@ static struct ccu_div dpu1_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_HW("dpu1",
 					      dpu1_pll_clk_parent,
 					      &ccu_div_ops,
-					      0),
+					      CLK_SET_RATE_UNGATE),
 	},
 };
 
@@ -889,9 +942,9 @@ static CCU_GATE(CLK_GPU_CORE, gpu_core_clk, "gpu-core-clk", video_pll_clk_pd,
 static CCU_GATE(CLK_GPU_CFG_ACLK, gpu_cfg_aclk, "gpu-cfg-aclk",
 		video_pll_clk_pd, 0x0, 4, 0);
 static CCU_GATE(CLK_DPU_PIXELCLK0, dpu0_pixelclk, "dpu0-pixelclk",
-		dpu0_clk_pd, 0x0, 5, 0);
+		dpu0_clk_pd, 0x0, 5, CLK_SET_RATE_PARENT);
 static CCU_GATE(CLK_DPU_PIXELCLK1, dpu1_pixelclk, "dpu1-pixelclk",
-		dpu1_clk_pd, 0x0, 6, 0);
+		dpu1_clk_pd, 0x0, 6, CLK_SET_RATE_PARENT);
 static CCU_GATE(CLK_DPU_HCLK, dpu_hclk, "dpu-hclk", video_pll_clk_pd, 0x0,
 		7, 0);
 static CCU_GATE(CLK_DPU_ACLK, dpu_aclk, "dpu-aclk", video_pll_clk_pd, 0x0,
-- 
2.50.1

[PATCH v3 4/4] clk: thead: th1520-ap: set all AXI clocks to CLK_IS_CRITICAL

[Icenowy Zheng]

The AXI crossbar of TH1520 has no proper timeout handling, which means
gating AXI clocks can easily lead to bus timeout and thus system hang.

Set all AXI clock gates to CLK_IS_CRITICAL. All these clock gates are
ungated by default on system reset.

In addition, convert all current CLK_IGNORE_UNUSED usage to
CLK_IS_CRITICAL to prevent unwanted clock gating.

Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Reviewed-by: Drew Fustini <fustini@kernel.org>
---
No changes in v2 except for rebasing error fixes (which I sent as FIXED
patches in v1).
Changes in v3:
- Rebased atop ccu_gate refactor.
- Added Drew's R-b.

 drivers/clk/thead/clk-th1520-ap.c | 44 +++++++++++++++----------------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/drivers/clk/thead/clk-th1520-ap.c b/drivers/clk/thead/clk-th1520-ap.c
index 54222b3219ccf..26e55e1c60148 100644
--- a/drivers/clk/thead/clk-th1520-ap.c
+++ b/drivers/clk/thead/clk-th1520-ap.c
@@ -559,7 +559,7 @@ static struct ccu_div axi4_cpusys2_aclk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_HW("axi4-cpusys2-aclk",
 					      gmac_pll_clk_parent,
 					      &ccu_div_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -581,7 +581,7 @@ static struct ccu_div axi_aclk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("axi-aclk",
 						      axi_parents,
 						      &ccu_div_ops,
-						      0),
+						      CLK_IS_CRITICAL),
 	},
 };
 
@@ -730,7 +730,7 @@ static struct ccu_div apb_pclk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_DATA("apb-pclk",
 						      apb_parents,
 						      &ccu_div_ops,
-						      CLK_IGNORE_UNUSED),
+						      CLK_IS_CRITICAL),
 	},
 };
 
@@ -761,7 +761,7 @@ static struct ccu_div vi_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_HW("vi",
 					      video_pll_clk_parent,
 					      &ccu_div_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -786,7 +786,7 @@ static struct ccu_div vo_axi_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_HW("vo-axi",
 					      video_pll_clk_parent,
 					      &ccu_div_ops,
-					      0),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -811,7 +811,7 @@ static struct ccu_div vp_axi_clk = {
 		.hw.init	= CLK_HW_INIT_PARENTS_HW("vp-axi",
 					      video_pll_clk_parent,
 					      &ccu_div_ops,
-					      CLK_IGNORE_UNUSED),
+					      CLK_IS_CRITICAL),
 	},
 };
 
@@ -872,27 +872,27 @@ static const struct clk_parent_data emmc_sdio_ref_clk_pd[] = {
 static CCU_GATE(CLK_BROM, brom_clk, "brom", ahb2_cpusys_hclk_pd, 0x100, 4, 0);
 static CCU_GATE(CLK_BMU, bmu_clk, "bmu", axi4_cpusys2_aclk_pd, 0x100, 5, 0);
 static CCU_GATE(CLK_AON2CPU_A2X, aon2cpu_a2x_clk, "aon2cpu-a2x", axi4_cpusys2_aclk_pd,
-		0x134, 8, 0);
+		0x134, 8, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_X2X_CPUSYS, x2x_cpusys_clk, "x2x-cpusys", axi4_cpusys2_aclk_pd,
-		0x134, 7, 0);
+		0x134, 7, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_CPU2AON_X2H, cpu2aon_x2h_clk, "cpu2aon-x2h", axi_aclk_pd,
-		0x138, 8, CLK_IGNORE_UNUSED);
+		0x138, 8, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_CPU2PERI_X2H, cpu2peri_x2h_clk, "cpu2peri-x2h", axi4_cpusys2_aclk_pd,
-		0x140, 9, CLK_IGNORE_UNUSED);
+		0x140, 9, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_PERISYS_APB1_HCLK, perisys_apb1_hclk, "perisys-apb1-hclk", perisys_ahb_hclk_pd,
-		0x150, 9, CLK_IGNORE_UNUSED);
+		0x150, 9, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_PERISYS_APB2_HCLK, perisys_apb2_hclk, "perisys-apb2-hclk", perisys_ahb_hclk_pd,
-		0x150, 10, CLK_IGNORE_UNUSED);
+		0x150, 10, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_PERISYS_APB3_HCLK, perisys_apb3_hclk, "perisys-apb3-hclk", perisys_ahb_hclk_pd,
-		0x150, 11, CLK_IGNORE_UNUSED);
+		0x150, 11, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_PERISYS_APB4_HCLK, perisys_apb4_hclk, "perisys-apb4-hclk", perisys_ahb_hclk_pd,
 		0x150, 12, 0);
 static const struct clk_parent_data perisys_apb4_hclk_pd[] = {
 	{ .hw = &perisys_apb4_hclk.gate.hw },
 };
 
-static CCU_GATE(CLK_NPU_AXI, npu_axi_clk, "npu-axi", axi_aclk_pd, 0x1c8, 5, 0);
-static CCU_GATE(CLK_CPU2VP, cpu2vp_clk, "cpu2vp", axi_aclk_pd, 0x1e0, 13, 0);
+static CCU_GATE(CLK_NPU_AXI, npu_axi_clk, "npu-axi", axi_aclk_pd, 0x1c8, 5, CLK_IS_CRITICAL);
+static CCU_GATE(CLK_CPU2VP, cpu2vp_clk, "cpu2vp", axi_aclk_pd, 0x1e0, 13, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_EMMC_SDIO, emmc_sdio_clk, "emmc-sdio", emmc_sdio_ref_clk_pd, 0x204, 30, 0);
 static CCU_GATE(CLK_GMAC1, gmac1_clk, "gmac1", gmac_pll_clk_pd, 0x204, 26, 0);
 static CCU_GATE(CLK_PADCTRL1, padctrl1_clk, "padctrl1", perisys_apb_pclk_pd, 0x204, 24, 0);
@@ -936,11 +936,11 @@ static CCU_GATE(CLK_SRAM2, sram2_clk, "sram2", axi_aclk_pd, 0x20c, 2, 0);
 static CCU_GATE(CLK_SRAM3, sram3_clk, "sram3", axi_aclk_pd, 0x20c, 1, 0);
 
 static CCU_GATE(CLK_AXI4_VO_ACLK, axi4_vo_aclk, "axi4-vo-aclk",
-		video_pll_clk_pd, 0x0, 0, 0);
+		video_pll_clk_pd, 0x0, 0, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_GPU_CORE, gpu_core_clk, "gpu-core-clk", video_pll_clk_pd,
 		0x0, 3, 0);
 static CCU_GATE(CLK_GPU_CFG_ACLK, gpu_cfg_aclk, "gpu-cfg-aclk",
-		video_pll_clk_pd, 0x0, 4, 0);
+		video_pll_clk_pd, 0x0, 4, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_DPU_PIXELCLK0, dpu0_pixelclk, "dpu0-pixelclk",
 		dpu0_clk_pd, 0x0, 5, CLK_SET_RATE_PARENT);
 static CCU_GATE(CLK_DPU_PIXELCLK1, dpu1_pixelclk, "dpu1-pixelclk",
@@ -972,9 +972,9 @@ static CCU_GATE(CLK_MIPI_DSI1_REFCLK, mipi_dsi1_refclk, "mipi-dsi1-refclk",
 static CCU_GATE(CLK_HDMI_I2S, hdmi_i2s_clk, "hdmi-i2s-clk", video_pll_clk_pd,
 		0x0, 19, 0);
 static CCU_GATE(CLK_X2H_DPU1_ACLK, x2h_dpu1_aclk, "x2h-dpu1-aclk",
-		video_pll_clk_pd, 0x0, 20, 0);
+		video_pll_clk_pd, 0x0, 20, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_X2H_DPU_ACLK, x2h_dpu_aclk, "x2h-dpu-aclk",
-		video_pll_clk_pd, 0x0, 21, 0);
+		video_pll_clk_pd, 0x0, 21, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_AXI4_VO_PCLK, axi4_vo_pclk, "axi4-vo-pclk",
 		video_pll_clk_pd, 0x0, 22, 0);
 static CCU_GATE(CLK_IOPMP_VOSYS_DPU_PCLK, iopmp_vosys_dpu_pclk,
@@ -984,11 +984,11 @@ static CCU_GATE(CLK_IOPMP_VOSYS_DPU1_PCLK, iopmp_vosys_dpu1_pclk,
 static CCU_GATE(CLK_IOPMP_VOSYS_GPU_PCLK, iopmp_vosys_gpu_pclk,
 		"iopmp-vosys-gpu-pclk", video_pll_clk_pd, 0x0, 25, 0);
 static CCU_GATE(CLK_IOPMP_DPU1_ACLK, iopmp_dpu1_aclk, "iopmp-dpu1-aclk",
-		video_pll_clk_pd, 0x0, 27, 0);
+		video_pll_clk_pd, 0x0, 27, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_IOPMP_DPU_ACLK, iopmp_dpu_aclk, "iopmp-dpu-aclk",
-		video_pll_clk_pd, 0x0, 28, 0);
+		video_pll_clk_pd, 0x0, 28, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_IOPMP_GPU_ACLK, iopmp_gpu_aclk, "iopmp-gpu-aclk",
-		video_pll_clk_pd, 0x0, 29, 0);
+		video_pll_clk_pd, 0x0, 29, CLK_IS_CRITICAL);
 static CCU_GATE(CLK_MIPIDSI0_PIXCLK, mipi_dsi0_pixclk, "mipi-dsi0-pixclk",
 		video_pll_clk_pd, 0x0, 30, 0);
 static CCU_GATE(CLK_MIPIDSI1_PIXCLK, mipi_dsi1_pixclk, "mipi-dsi1-pixclk",
-- 
2.50.1

Re: [PATCH v3 0/4] clk: thead: Changes to TH1520 clock driver for disp

[Drew Fustini]

On Sat, Aug 16, 2025 at 05:11:09PM +0800, Icenowy Zheng wrote:
> This patchset is my changes to the TH1520 clock driver, mainly for
> supporting the display controller.
> 
> The first patch is previously a dependency of this patchset before v3,
> but a rebase operation in v3 changed it and it's now pulled into this
> patchset.
> 
> The 2nd and 3rd ones are functionality additions, with the first one
> adding support for enabling/disabling PLLs (for DPU PLL) and the second
> one adding support for changing DPU dividers.
> 
> The 4th one is to address hang issues met when testing the DPU driver
> w/o clk_ignore_unused command line option.
> 
> The patchset is rebased atop the padctrl0 parent fix patchset (which
> contains refactor of ccu_gate) at [1] in v3.
> 
> [1] https://lore.kernel.org/linux-riscv/20250816084445.2582692-1-uwu@icenowy.me/
> 
> Icenowy Zheng (3):
>   clk: thead: add support for enabling/disabling PLLs
>   clk: thead: support changing DPU pixel clock rate
>   clk: thead: th1520-ap: set all AXI clocks to CLK_IS_CRITICAL
> 
> Michal Wilczynski (1):
>   clk: thead: Correct parent for DPU pixel clocks
> 
>  drivers/clk/thead/clk-th1520-ap.c | 153 +++++++++++++++++++++++-------
>  1 file changed, 121 insertions(+), 32 deletions(-)
> 
> -- 
> 2.50.1
> 

Thank you, I've applied this to thead-clk-for-next [1]:

c567bc5fc68c clk: thead: th1520-ap: set all AXI clocks to CLK_IS_CRITICAL
8fede7ff692c clk: thead: support changing DPU pixel clock rate
56a48c1833aa clk: thead: add support for enabling/disabling PLLs
c51a37ffea38 clk: thead: Correct parent for DPU pixel clocks

-Drew

[1] https://git.kernel.org/pub/scm/linux/kernel/git/fustini/linux.git/log/?h=thead-clk-for-next