[PATCH V2 0/4] clk: imx: imx8m: fix a53 cpu clock

[PATCH V2 0/4] clk: imx: imx8m: fix a53 cpu clock

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

V2:
 Fix i.MX8MP build
 Update cover letter, i.MX7D not have this issue 

The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
signoff timing is 1Ghz, however the A53 core which sources from CCM
root could run above 1GHz which voilates the CCM.

There is a CORE_SEL slice before A53 core, we need configure the
CORE_SEL slice source from ARM PLL, not A53 CCM clk root.

The A53 CCM clk root should only be used when need to change ARM PLL
frequency.

Peng Fan (4):
  clk: imx: imx8mq: fix a53 cpu clock
  clk: imx: imx8mm: fix a53 cpu clock
  clk: imx: imx8mn: fix a53 cpu clock
  clk: imx: imx8mp: fix a53 cpu clock

 drivers/clk/imx/clk-imx8mm.c             | 16 ++++++++++++----
 drivers/clk/imx/clk-imx8mn.c             | 16 ++++++++++++----
 drivers/clk/imx/clk-imx8mp.c             | 16 ++++++++++++----
 drivers/clk/imx/clk-imx8mq.c             | 16 ++++++++++++----
 include/dt-bindings/clock/imx8mm-clock.h |  4 +++-
 include/dt-bindings/clock/imx8mn-clock.h |  4 +++-
 include/dt-bindings/clock/imx8mp-clock.h |  3 ++-
 include/dt-bindings/clock/imx8mq-clock.h |  4 +++-
 8 files changed, 59 insertions(+), 20 deletions(-)

-- 
2.16.4

[PATCH V2 1/4] clk: imx: imx8mq: fix a53 cpu clock

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
signoff timing is 1Ghz, however the A53 core which sources from CCM
root could run above 1GHz which voilates the CCM.

There is a CORE_SEL slice before A53 core, we need configure the
CORE_SEL slice source from ARM PLL, not A53 CCM clk root.

The A53 CCM clk root should only be used when need to change ARM PLL
frequency.

Add arm_a53_core clk that could source from arm_a53_div and arm_pll_out.
Configure a53 ccm root sources from 800MHz sys pll
Configure a53 core sources from arm_pll_out
Mark arm_a53_core as critical clock

Fixes: db27e40b27f1 ("clk: imx8mq: Add the missing ARM clock")
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V2:
 None

 drivers/clk/imx/clk-imx8mq.c             | 16 ++++++++++++----
 include/dt-bindings/clock/imx8mq-clock.h |  4 +++-
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/imx/clk-imx8mq.c b/drivers/clk/imx/clk-imx8mq.c
index b031183ff427..82a16b8e98a9 100644
--- a/drivers/clk/imx/clk-imx8mq.c
+++ b/drivers/clk/imx/clk-imx8mq.c
@@ -41,6 +41,8 @@ static const char * const video2_pll_out_sels[] = {"video2_pll1_ref_sel", };
 static const char * const imx8mq_a53_sels[] = {"osc_25m", "arm_pll_out", "sys2_pll_500m", "sys2_pll_1000m",
 					"sys1_pll_800m", "sys1_pll_400m", "audio_pll1_out", "sys3_pll_out", };
 
+static const char * const imx8mq_a53_core_sels[] = {"arm_a53_div", "arm_pll_out", };
+
 static const char * const imx8mq_arm_m4_sels[] = {"osc_25m", "sys2_pll_200m", "sys2_pll_250m", "sys1_pll_266m",
 					"sys1_pll_800m", "audio_pll1_out", "video_pll1_out", "sys3_pll_out", };
 
@@ -411,6 +413,9 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MQ_CLK_GPU_CORE_DIV] = imx8m_clk_hw_composite_core("gpu_core_div", imx8mq_gpu_core_sels, base + 0x8180);
 	hws[IMX8MQ_CLK_GPU_SHADER_DIV] = imx8m_clk_hw_composite("gpu_shader_div", imx8mq_gpu_shader_sels, base + 0x8200);
 
+	/* CORE SEL */
+	hws[IMX8MQ_CLK_A53_CORE] = imx_clk_hw_mux2_flags("arm_a53_core", base + 0x9880, 24, 1, imx8mq_a53_core_sels, ARRAY_SIZE(imx8mq_a53_core_sels), CLK_IS_CRITICAL);
+
 	/* BUS */
 	hws[IMX8MQ_CLK_MAIN_AXI] = imx8m_clk_hw_composite_critical("main_axi", imx8mq_main_axi_sels, base + 0x8800);
 	hws[IMX8MQ_CLK_ENET_AXI] = imx8m_clk_hw_composite("enet_axi", imx8mq_enet_axi_sels, base + 0x8880);
@@ -574,11 +579,14 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MQ_GPT_3M_CLK] = imx_clk_hw_fixed_factor("gpt_3m", "osc_25m", 1, 8);
 	hws[IMX8MQ_CLK_DRAM_ALT_ROOT] = imx_clk_hw_fixed_factor("dram_alt_root", "dram_alt", 1, 4);
 
-	hws[IMX8MQ_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_div",
-					   hws[IMX8MQ_CLK_A53_DIV]->clk,
-					   hws[IMX8MQ_CLK_A53_SRC]->clk,
+	clk_hw_set_parent(hws[IMX8MQ_CLK_A53_SRC], hws[IMX8MQ_SYS1_PLL_800M]);
+	clk_hw_set_parent(hws[IMX8MQ_CLK_A53_CORE], hws[IMX8MQ_ARM_PLL_OUT]);
+
+	hws[IMX8MQ_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_core",
+					   hws[IMX8MQ_CLK_A53_CORE]->clk,
+					   hws[IMX8MQ_CLK_A53_CORE]->clk,
 					   hws[IMX8MQ_ARM_PLL_OUT]->clk,
-					   hws[IMX8MQ_SYS1_PLL_800M]->clk);
+					   hws[IMX8MQ_CLK_A53_DIV]->clk);
 
 	imx_check_clk_hws(hws, IMX8MQ_CLK_END);
 
diff --git a/include/dt-bindings/clock/imx8mq-clock.h b/include/dt-bindings/clock/imx8mq-clock.h
index 3bab9b21c8d7..ac71e9e502b8 100644
--- a/include/dt-bindings/clock/imx8mq-clock.h
+++ b/include/dt-bindings/clock/imx8mq-clock.h
@@ -424,6 +424,8 @@
 #define IMX8MQ_SYS2_PLL_500M_CG			283
 #define IMX8MQ_SYS2_PLL_1000M_CG		284
 
-#define IMX8MQ_CLK_END				285
+#define IMX8MQ_CLK_A53_CORE			285
+
+#define IMX8MQ_CLK_END				286
 
 #endif /* __DT_BINDINGS_CLOCK_IMX8MQ_H */
-- 
2.16.4

[PATCH V2 2/4] clk: imx: imx8mm: fix a53 cpu clock

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
signoff timing is 1Ghz, however the A53 core which sources from CCM
root could run above 1GHz which voilates the CCM.

There is a CORE_SEL slice before A53 core, we need configure the
CORE_SEL slice source from ARM PLL, not A53 CCM clk root.

The A53 CCM clk root should only be used when need to change ARM PLL
frequency.

Add arm_a53_core clk that could source from arm_a53_div and arm_pll_out.
Configure a53 ccm root sources from 800MHz sys pll
Configure a53 core sources from arm_pll_out
Mark arm_a53_core as critical clock

Fixes: ba5625c3e272 ("clk: imx: Add clock driver support for imx8mm")
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V2:
 None

 drivers/clk/imx/clk-imx8mm.c             | 16 ++++++++++++----
 include/dt-bindings/clock/imx8mm-clock.h |  4 +++-
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/imx/clk-imx8mm.c b/drivers/clk/imx/clk-imx8mm.c
index 197ba2cdab7d..ad7a77e3276c 100644
--- a/drivers/clk/imx/clk-imx8mm.c
+++ b/drivers/clk/imx/clk-imx8mm.c
@@ -41,6 +41,8 @@ static const char *sys_pll3_bypass_sels[] = {"sys_pll3", "sys_pll3_ref_sel", };
 static const char *imx8mm_a53_sels[] = {"osc_24m", "arm_pll_out", "sys_pll2_500m", "sys_pll2_1000m",
 					"sys_pll1_800m", "sys_pll1_400m", "audio_pll1_out", "sys_pll3_out", };
 
+static const char * const imx8mm_a53_core_sels[] = {"arm_a53_div", "arm_pll_out", };
+
 static const char *imx8mm_m4_sels[] = {"osc_24m", "sys_pll2_200m", "sys_pll2_250m", "sys_pll1_266m",
 				       "sys_pll1_800m", "audio_pll1_out", "video_pll1_out", "sys_pll3_out", };
 
@@ -422,6 +424,9 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MM_CLK_GPU3D_DIV] = imx8m_clk_hw_composite_core("gpu3d_div", imx8mm_gpu3d_sels, base + 0x8180);
 	hws[IMX8MM_CLK_GPU2D_DIV] = imx8m_clk_hw_composite_core("gpu2d_div", imx8mm_gpu2d_sels, base + 0x8200);
 
+	/* CORE SEL */
+	hws[IMX8MM_CLK_A53_CORE] = imx_clk_hw_mux2_flags("arm_a53_core", base + 0x9880, 24, 1, imx8mm_a53_core_sels, ARRAY_SIZE(imx8mm_a53_core_sels), CLK_IS_CRITICAL);
+
 	/* BUS */
 	hws[IMX8MM_CLK_MAIN_AXI] = imx8m_clk_hw_composite_critical("main_axi",  imx8mm_main_axi_sels, base + 0x8800);
 	hws[IMX8MM_CLK_ENET_AXI] = imx8m_clk_hw_composite("enet_axi", imx8mm_enet_axi_sels, base + 0x8880);
@@ -587,11 +592,14 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MM_CLK_DRAM_ALT_ROOT] = imx_clk_hw_fixed_factor("dram_alt_root", "dram_alt", 1, 4);
 	hws[IMX8MM_CLK_DRAM_CORE] = imx_clk_hw_mux2_flags("dram_core_clk", base + 0x9800, 24, 1, imx8mm_dram_core_sels, ARRAY_SIZE(imx8mm_dram_core_sels), CLK_IS_CRITICAL);
 
-	hws[IMX8MM_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_div",
-					   hws[IMX8MM_CLK_A53_DIV]->clk,
-					   hws[IMX8MM_CLK_A53_SRC]->clk,
+	clk_hw_set_parent(hws[IMX8MM_CLK_A53_SRC], hws[IMX8MM_SYS_PLL1_800M]);
+	clk_hw_set_parent(hws[IMX8MM_CLK_A53_CORE], hws[IMX8MM_ARM_PLL_OUT]);
+
+	hws[IMX8MM_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_core",
+					   hws[IMX8MM_CLK_A53_CORE]->clk,
+					   hws[IMX8MM_CLK_A53_CORE]->clk,
 					   hws[IMX8MM_ARM_PLL_OUT]->clk,
-					   hws[IMX8MM_SYS_PLL1_800M]->clk);
+					   hws[IMX8MM_CLK_A53_DIV]->clk);
 
 	imx_check_clk_hws(hws, IMX8MM_CLK_END);
 
diff --git a/include/dt-bindings/clock/imx8mm-clock.h b/include/dt-bindings/clock/imx8mm-clock.h
index edeece2289f0..8b585a910ddb 100644
--- a/include/dt-bindings/clock/imx8mm-clock.h
+++ b/include/dt-bindings/clock/imx8mm-clock.h
@@ -265,6 +265,8 @@
 #define IMX8MM_SYS_PLL2_333M_CG			244
 #define IMX8MM_SYS_PLL2_500M_CG			245
 
-#define IMX8MM_CLK_END				246
+#define IMX8MM_CLK_A53_CORE			246
+
+#define IMX8MM_CLK_END				247
 
 #endif
-- 
2.16.4

[PATCH V2 3/4] clk: imx: imx8mn: fix a53 cpu clock

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
signoff timing is 1Ghz, however the A53 core which sources from CCM
root could run above 1GHz which voilates the CCM.

There is a CORE_SEL slice before A53 core, we need configure the
CORE_SEL slice source from ARM PLL, not A53 CCM clk root.

The A53 CCM clk root should only be used when need to change ARM PLL
frequency.

Add arm_a53_core clk that could source from arm_a53_div and arm_pll_out.
Configure a53 ccm root sources from 800MHz sys pll
Configure a53 core sources from arm_pll_out
Mark arm_a53_core as critical clk.

Fixes: 96d6392b54db ("clk: imx: Add support for i.MX8MN clock driver")
Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V2:
 None

 drivers/clk/imx/clk-imx8mn.c             | 16 ++++++++++++----
 include/dt-bindings/clock/imx8mn-clock.h |  4 +++-
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/imx/clk-imx8mn.c b/drivers/clk/imx/clk-imx8mn.c
index ce2ba3dce483..01c1034834fc 100644
--- a/drivers/clk/imx/clk-imx8mn.c
+++ b/drivers/clk/imx/clk-imx8mn.c
@@ -40,6 +40,8 @@ static const char * const imx8mn_a53_sels[] = {"osc_24m", "arm_pll_out", "sys_pl
 					       "sys_pll2_1000m", "sys_pll1_800m", "sys_pll1_400m",
 					       "audio_pll1_out", "sys_pll3_out", };
 
+static const char * const imx8mn_a53_core_sels[] = {"arm_a53_div", "arm_pll_out", };
+
 static const char * const imx8mn_gpu_core_sels[] = {"osc_24m", "gpu_pll_out", "sys_pll1_800m",
 						    "sys_pll3_out", "sys_pll2_1000m", "audio_pll1_out",
 						    "video_pll1_out", "audio_pll2_out", };
@@ -419,6 +421,9 @@ static int imx8mn_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MN_CLK_GPU_CORE_DIV] = imx8m_clk_hw_composite_core("gpu_core_div", imx8mn_gpu_core_sels, base + 0x8180);
 	hws[IMX8MN_CLK_GPU_SHADER_DIV] = imx8m_clk_hw_composite_core("gpu_shader_div", imx8mn_gpu_shader_sels, base + 0x8200);
 
+	/* CORE SEL */
+	hws[IMX8MN_CLK_A53_CORE] = imx_clk_hw_mux2_flags("arm_a53_core", base + 0x9880, 24, 1, imx8mn_a53_core_sels, ARRAY_SIZE(imx8mn_a53_core_sels), CLK_IS_CRITICAL);
+
 	/* BUS */
 	hws[IMX8MN_CLK_MAIN_AXI] = imx8m_clk_hw_composite_critical("main_axi", imx8mn_main_axi_sels, base + 0x8800);
 	hws[IMX8MN_CLK_ENET_AXI] = imx8m_clk_hw_composite("enet_axi", imx8mn_enet_axi_sels, base + 0x8880);
@@ -547,11 +552,14 @@ static int imx8mn_clocks_probe(struct platform_device *pdev)
 
 	hws[IMX8MN_CLK_DRAM_ALT_ROOT] = imx_clk_hw_fixed_factor("dram_alt_root", "dram_alt", 1, 4);
 
-	hws[IMX8MN_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_div",
-					   hws[IMX8MN_CLK_A53_DIV]->clk,
-					   hws[IMX8MN_CLK_A53_SRC]->clk,
+	clk_hw_set_parent(hws[IMX8MN_CLK_A53_SRC], hws[IMX8MN_SYS_PLL1_800M]);
+	clk_hw_set_parent(hws[IMX8MN_CLK_A53_CORE], hws[IMX8MN_ARM_PLL_OUT]);
+
+	hws[IMX8MN_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_core",
+					   hws[IMX8MN_CLK_A53_CORE]->clk,
+					   hws[IMX8MN_CLK_A53_CORE]->clk,
 					   hws[IMX8MN_ARM_PLL_OUT]->clk,
-					   hws[IMX8MN_SYS_PLL1_800M]->clk);
+					   hws[IMX8MN_CLK_A53_DIV]->clk);
 
 	imx_check_clk_hws(hws, IMX8MN_CLK_END);
 
diff --git a/include/dt-bindings/clock/imx8mn-clock.h b/include/dt-bindings/clock/imx8mn-clock.h
index 0f2b8423ce1d..7ec4c24d6e06 100644
--- a/include/dt-bindings/clock/imx8mn-clock.h
+++ b/include/dt-bindings/clock/imx8mn-clock.h
@@ -228,6 +228,8 @@
 #define IMX8MN_SYS_PLL2_333M_CG			209
 #define IMX8MN_SYS_PLL2_500M_CG			210
 
-#define IMX8MN_CLK_END				211
+#define IMX8MN_CLK_A53_CORE			211
+
+#define IMX8MN_CLK_END				212
 
 #endif
-- 
2.16.4

[PATCH V2 4/4] clk: imx: imx8mp: fix a53 cpu clock

[Peng Fan]

From: Peng Fan <peng.fan@nxp.com>

The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
signoff timing is 1Ghz, however the A53 core which sources from CCM
root could run above 1GHz which voilates the CCM.

There is a CORE_SEL slice before A53 core, we need configure the
CORE_SEL slice source from ARM PLL, not A53 CCM clk root.

The A53 CCM clk root should only be used when need to change ARM PLL
frequency.

Add arm_a53_core clk that could source from arm_a53_div and arm_pll_out.
Configure a53 ccm root sources from 800MHz sys pll
Configure a53 core sources from arm_pll_out
Mark arm_a53_core as critical clk

Reviewed-by: Jacky Bai <ping.bai@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V2:
 Fix build

 drivers/clk/imx/clk-imx8mp.c             | 16 ++++++++++++----
 include/dt-bindings/clock/imx8mp-clock.h |  3 ++-
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/imx/clk-imx8mp.c b/drivers/clk/imx/clk-imx8mp.c
index f6c120cca0d4..6ac4746898cb 100644
--- a/drivers/clk/imx/clk-imx8mp.c
+++ b/drivers/clk/imx/clk-imx8mp.c
@@ -34,6 +34,8 @@ static const char * const imx8mp_a53_sels[] = {"osc_24m", "arm_pll_out", "sys_pl
 					       "sys_pll2_1000m", "sys_pll1_800m", "sys_pll1_400m",
 					       "audio_pll1_out", "sys_pll3_out", };
 
+static const char * const imx8mp_a53_core_sels[] = {"arm_a53_div", "arm_pll_out", };
+
 static const char * const imx8mp_m7_sels[] = {"osc_24m", "sys_pll2_200m", "sys_pll2_250m",
 					      "vpu_pll_out", "sys_pll1_800m", "audio_pll1_out",
 					      "video_pll1_out", "sys_pll3_out", };
@@ -553,6 +555,9 @@ static int imx8mp_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MP_CLK_HSIO_AXI_DIV] = imx_clk_hw_divider2("hsio_axi_div", "hsio_axi_cg", ccm_base + 0x8380, 0, 3);
 	hws[IMX8MP_CLK_MEDIA_ISP_DIV] = imx_clk_hw_divider2("media_isp_div", "media_isp_cg", ccm_base + 0x8400, 0, 3);
 
+	/* CORE SEL */
+	hws[IMX8MP_CLK_A53_CORE] = imx_clk_hw_mux2_flags("arm_a53_core", ccm_base + 0x9880, 24, 1, imx8mp_a53_core_sels, ARRAY_SIZE(imx8mp_a53_core_sels), CLK_IS_CRITICAL);
+
 	hws[IMX8MP_CLK_MAIN_AXI] = imx8m_clk_hw_composite_critical("main_axi", imx8mp_main_axi_sels, ccm_base + 0x8800);
 	hws[IMX8MP_CLK_ENET_AXI] = imx8m_clk_hw_composite("enet_axi", imx8mp_enet_axi_sels, ccm_base + 0x8880);
 	hws[IMX8MP_CLK_NAND_USDHC_BUS] = imx8m_clk_hw_composite_critical("nand_usdhc_bus", imx8mp_nand_usdhc_sels, ccm_base + 0x8900);
@@ -722,11 +727,14 @@ static int imx8mp_clocks_probe(struct platform_device *pdev)
 	hws[IMX8MP_CLK_VPU_ROOT] = imx_clk_hw_gate4("vpu_root_clk", "vpu_bus", ccm_base + 0x4630, 0);
 	hws[IMX8MP_CLK_AUDIO_ROOT] = imx_clk_hw_gate4("audio_root_clk", "ipg_root", ccm_base + 0x4650, 0);
 
-	hws[IMX8MP_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_div",
-					     hws[IMX8MP_CLK_A53_DIV]->clk,
-					     hws[IMX8MP_CLK_A53_SRC]->clk,
+	clk_hw_set_parent(hws[IMX8MP_CLK_A53_SRC], hws[IMX8MP_SYS_PLL1_800M]);
+	clk_hw_set_parent(hws[IMX8MP_CLK_A53_CORE], hws[IMX8MP_ARM_PLL_OUT]);
+
+	hws[IMX8MP_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_core",
+					     hws[IMX8MP_CLK_A53_CORE]->clk,
+					     hws[IMX8MP_CLK_A53_CORE]->clk,
 					     hws[IMX8MP_ARM_PLL_OUT]->clk,
-					     hws[IMX8MP_SYS_PLL1_800M]->clk);
+					     hws[IMX8MP_CLK_A53_DIV]->clk);
 
 	imx_check_clk_hws(hws, IMX8MP_CLK_END);
 
diff --git a/include/dt-bindings/clock/imx8mp-clock.h b/include/dt-bindings/clock/imx8mp-clock.h
index 2fab63186bca..c92d1f4117eb 100644
--- a/include/dt-bindings/clock/imx8mp-clock.h
+++ b/include/dt-bindings/clock/imx8mp-clock.h
@@ -294,7 +294,8 @@
 #define IMX8MP_CLK_DRAM_ALT_ROOT		285
 #define IMX8MP_CLK_DRAM_CORE			286
 #define IMX8MP_CLK_ARM				287
+#define IMX8MP_CLK_A53_CORE			288
 
-#define IMX8MP_CLK_END				288
+#define IMX8MP_CLK_END				289
 
 #endif
-- 
2.16.4

Re: [PATCH V2 1/4] clk: imx: imx8mq: fix a53 cpu clock

[Shawn Guo]

On Tue, Jan 14, 2020 at 07:27:15AM +0000, Peng Fan wrote:
> From: Peng Fan <peng.fan@nxp.com>

The 'imx: ' in subject is not really needed.  'clk: imx8mq: ' should be
already clear enough.

> 
> The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
> signoff timing is 1Ghz,

Is this restriction mentioned in any document? 

> however the A53 core which sources from CCM
> root could run above 1GHz which voilates the CCM.

s/voilates/violates

> 
> There is a CORE_SEL slice before A53 core, we need configure the

s/need/need to

> CORE_SEL slice source from ARM PLL, not A53 CCM clk root.
> 
> The A53 CCM clk root should only be used when need to change ARM PLL
> frequency.
> 
> Add arm_a53_core clk that could source from arm_a53_div and arm_pll_out.
> Configure a53 ccm root sources from 800MHz sys pll
> Configure a53 core sources from arm_pll_out
> Mark arm_a53_core as critical clock
> 
> Fixes: db27e40b27f1 ("clk: imx8mq: Add the missing ARM clock")

We have been running this for quite a while with OPPs above 1GHz.  Why
didn't we hear any issue report?

Shawn

> Reviewed-by: Jacky Bai <ping.bai@nxp.com>
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---
> 
> V2:
>  None
> 
>  drivers/clk/imx/clk-imx8mq.c             | 16 ++++++++++++----
>  include/dt-bindings/clock/imx8mq-clock.h |  4 +++-
>  2 files changed, 15 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/clk/imx/clk-imx8mq.c b/drivers/clk/imx/clk-imx8mq.c
> index b031183ff427..82a16b8e98a9 100644
> --- a/drivers/clk/imx/clk-imx8mq.c
> +++ b/drivers/clk/imx/clk-imx8mq.c
> @@ -41,6 +41,8 @@ static const char * const video2_pll_out_sels[] = {"video2_pll1_ref_sel", };
>  static const char * const imx8mq_a53_sels[] = {"osc_25m", "arm_pll_out", "sys2_pll_500m", "sys2_pll_1000m",
>  					"sys1_pll_800m", "sys1_pll_400m", "audio_pll1_out", "sys3_pll_out", };
>  
> +static const char * const imx8mq_a53_core_sels[] = {"arm_a53_div", "arm_pll_out", };
> +
>  static const char * const imx8mq_arm_m4_sels[] = {"osc_25m", "sys2_pll_200m", "sys2_pll_250m", "sys1_pll_266m",
>  					"sys1_pll_800m", "audio_pll1_out", "video_pll1_out", "sys3_pll_out", };
>  
> @@ -411,6 +413,9 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
>  	hws[IMX8MQ_CLK_GPU_CORE_DIV] = imx8m_clk_hw_composite_core("gpu_core_div", imx8mq_gpu_core_sels, base + 0x8180);
>  	hws[IMX8MQ_CLK_GPU_SHADER_DIV] = imx8m_clk_hw_composite("gpu_shader_div", imx8mq_gpu_shader_sels, base + 0x8200);
>  
> +	/* CORE SEL */
> +	hws[IMX8MQ_CLK_A53_CORE] = imx_clk_hw_mux2_flags("arm_a53_core", base + 0x9880, 24, 1, imx8mq_a53_core_sels, ARRAY_SIZE(imx8mq_a53_core_sels), CLK_IS_CRITICAL);
> +
>  	/* BUS */
>  	hws[IMX8MQ_CLK_MAIN_AXI] = imx8m_clk_hw_composite_critical("main_axi", imx8mq_main_axi_sels, base + 0x8800);
>  	hws[IMX8MQ_CLK_ENET_AXI] = imx8m_clk_hw_composite("enet_axi", imx8mq_enet_axi_sels, base + 0x8880);
> @@ -574,11 +579,14 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
>  	hws[IMX8MQ_GPT_3M_CLK] = imx_clk_hw_fixed_factor("gpt_3m", "osc_25m", 1, 8);
>  	hws[IMX8MQ_CLK_DRAM_ALT_ROOT] = imx_clk_hw_fixed_factor("dram_alt_root", "dram_alt", 1, 4);
>  
> -	hws[IMX8MQ_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_div",
> -					   hws[IMX8MQ_CLK_A53_DIV]->clk,
> -					   hws[IMX8MQ_CLK_A53_SRC]->clk,
> +	clk_hw_set_parent(hws[IMX8MQ_CLK_A53_SRC], hws[IMX8MQ_SYS1_PLL_800M]);
> +	clk_hw_set_parent(hws[IMX8MQ_CLK_A53_CORE], hws[IMX8MQ_ARM_PLL_OUT]);
> +
> +	hws[IMX8MQ_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_core",
> +					   hws[IMX8MQ_CLK_A53_CORE]->clk,
> +					   hws[IMX8MQ_CLK_A53_CORE]->clk,
>  					   hws[IMX8MQ_ARM_PLL_OUT]->clk,
> -					   hws[IMX8MQ_SYS1_PLL_800M]->clk);
> +					   hws[IMX8MQ_CLK_A53_DIV]->clk);
>  
>  	imx_check_clk_hws(hws, IMX8MQ_CLK_END);
>  
> diff --git a/include/dt-bindings/clock/imx8mq-clock.h b/include/dt-bindings/clock/imx8mq-clock.h
> index 3bab9b21c8d7..ac71e9e502b8 100644
> --- a/include/dt-bindings/clock/imx8mq-clock.h
> +++ b/include/dt-bindings/clock/imx8mq-clock.h
> @@ -424,6 +424,8 @@
>  #define IMX8MQ_SYS2_PLL_500M_CG			283
>  #define IMX8MQ_SYS2_PLL_1000M_CG		284
>  
> -#define IMX8MQ_CLK_END				285
> +#define IMX8MQ_CLK_A53_CORE			285
> +
> +#define IMX8MQ_CLK_END				286
>  
>  #endif /* __DT_BINDINGS_CLOCK_IMX8MQ_H */
> -- 
> 2.16.4
> 

RE: [PATCH V2 1/4] clk: imx: imx8mq: fix a53 cpu clock

[Peng Fan]

Hi Shawn,

> Subject: Re: [PATCH V2 1/4] clk: imx: imx8mq: fix a53 cpu clock
> 
> On Tue, Jan 14, 2020 at 07:27:15AM +0000, Peng Fan wrote:
> > From: Peng Fan <peng.fan@nxp.com>
> 
> The 'imx: ' in subject is not really needed.  'clk: imx8mq: ' should be already
> clear enough.
> 
> >
> > The A53 CCM clk root only accepts input up to 1GHz, CCM A53 root
> > signoff timing is 1Ghz,
> 
> Is this restriction mentioned in any document?

This information was not mentioned in documentation. But I have confirmed
the limitation with design team.

> 
> > however the A53 core which sources from CCM root could run above 1GHz
> > which voilates the CCM.
> 
> s/voilates/violates

Fix in v3.

> 
> >
> > There is a CORE_SEL slice before A53 core, we need configure the
> 
> s/need/need to

Fix in v3.

> 
> > CORE_SEL slice source from ARM PLL, not A53 CCM clk root.
> >
> > The A53 CCM clk root should only be used when need to change ARM PLL
> > frequency.
> >
> > Add arm_a53_core clk that could source from arm_a53_div and
> arm_pll_out.
> > Configure a53 ccm root sources from 800MHz sys pll Configure a53 core
> > sources from arm_pll_out Mark arm_a53_core as critical clock
> >
> > Fixes: db27e40b27f1 ("clk: imx8mq: Add the missing ARM clock")
> 
> We have been running this for quite a while with OPPs above 1GHz.  Why
> didn't we hear any issue report?

In room temperature, there might be no issue. But the A53 clk root
signoff timing is 1Ghz, so if we keep using the clk root for OPPs above
1GHz, we could not make sure there is no problem.

Thanks,
Peng.

> 
> Shawn
> 
> > Reviewed-by: Jacky Bai <ping.bai@nxp.com>
> > Signed-off-by: Peng Fan <peng.fan@nxp.com>
> > ---
> >
> > V2:
> >  None
> >
> >  drivers/clk/imx/clk-imx8mq.c             | 16 ++++++++++++----
> >  include/dt-bindings/clock/imx8mq-clock.h |  4 +++-
> >  2 files changed, 15 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/clk/imx/clk-imx8mq.c
> > b/drivers/clk/imx/clk-imx8mq.c index b031183ff427..82a16b8e98a9
> 100644
> > --- a/drivers/clk/imx/clk-imx8mq.c
> > +++ b/drivers/clk/imx/clk-imx8mq.c
> > @@ -41,6 +41,8 @@ static const char * const video2_pll_out_sels[] =
> > {"video2_pll1_ref_sel", };  static const char * const imx8mq_a53_sels[] =
> {"osc_25m", "arm_pll_out", "sys2_pll_500m", "sys2_pll_1000m",
> >  					"sys1_pll_800m", "sys1_pll_400m", "audio_pll1_out",
> > "sys3_pll_out", };
> >
> > +static const char * const imx8mq_a53_core_sels[] = {"arm_a53_div",
> > +"arm_pll_out", };
> > +
> >  static const char * const imx8mq_arm_m4_sels[] = {"osc_25m",
> "sys2_pll_200m", "sys2_pll_250m", "sys1_pll_266m",
> >  					"sys1_pll_800m", "audio_pll1_out", "video_pll1_out",
> > "sys3_pll_out", };
> >
> > @@ -411,6 +413,9 @@ static int imx8mq_clocks_probe(struct
> platform_device *pdev)
> >  	hws[IMX8MQ_CLK_GPU_CORE_DIV] =
> imx8m_clk_hw_composite_core("gpu_core_div", imx8mq_gpu_core_sels,
> base + 0x8180);
> >  	hws[IMX8MQ_CLK_GPU_SHADER_DIV] =
> > imx8m_clk_hw_composite("gpu_shader_div", imx8mq_gpu_shader_sels,
> base
> > + 0x8200);
> >
> > +	/* CORE SEL */
> > +	hws[IMX8MQ_CLK_A53_CORE] =
> imx_clk_hw_mux2_flags("arm_a53_core",
> > +base + 0x9880, 24, 1, imx8mq_a53_core_sels,
> > +ARRAY_SIZE(imx8mq_a53_core_sels), CLK_IS_CRITICAL);
> > +
> >  	/* BUS */
> >  	hws[IMX8MQ_CLK_MAIN_AXI] =
> imx8m_clk_hw_composite_critical("main_axi", imx8mq_main_axi_sels, base
> + 0x8800);
> >  	hws[IMX8MQ_CLK_ENET_AXI] = imx8m_clk_hw_composite("enet_axi",
> > imx8mq_enet_axi_sels, base + 0x8880); @@ -574,11 +579,14 @@ static int
> imx8mq_clocks_probe(struct platform_device *pdev)
> >  	hws[IMX8MQ_GPT_3M_CLK] = imx_clk_hw_fixed_factor("gpt_3m",
> "osc_25m", 1, 8);
> >  	hws[IMX8MQ_CLK_DRAM_ALT_ROOT] =
> > imx_clk_hw_fixed_factor("dram_alt_root", "dram_alt", 1, 4);
> >
> > -	hws[IMX8MQ_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_div",
> > -					   hws[IMX8MQ_CLK_A53_DIV]->clk,
> > -					   hws[IMX8MQ_CLK_A53_SRC]->clk,
> > +	clk_hw_set_parent(hws[IMX8MQ_CLK_A53_SRC],
> hws[IMX8MQ_SYS1_PLL_800M]);
> > +	clk_hw_set_parent(hws[IMX8MQ_CLK_A53_CORE],
> > +hws[IMX8MQ_ARM_PLL_OUT]);
> > +
> > +	hws[IMX8MQ_CLK_ARM] = imx_clk_hw_cpu("arm", "arm_a53_core",
> > +					   hws[IMX8MQ_CLK_A53_CORE]->clk,
> > +					   hws[IMX8MQ_CLK_A53_CORE]->clk,
> >  					   hws[IMX8MQ_ARM_PLL_OUT]->clk,
> > -					   hws[IMX8MQ_SYS1_PLL_800M]->clk);
> > +					   hws[IMX8MQ_CLK_A53_DIV]->clk);
> >
> >  	imx_check_clk_hws(hws, IMX8MQ_CLK_END);
> >
> > diff --git a/include/dt-bindings/clock/imx8mq-clock.h
> > b/include/dt-bindings/clock/imx8mq-clock.h
> > index 3bab9b21c8d7..ac71e9e502b8 100644
> > --- a/include/dt-bindings/clock/imx8mq-clock.h
> > +++ b/include/dt-bindings/clock/imx8mq-clock.h
> > @@ -424,6 +424,8 @@
> >  #define IMX8MQ_SYS2_PLL_500M_CG			283
> >  #define IMX8MQ_SYS2_PLL_1000M_CG		284
> >
> > -#define IMX8MQ_CLK_END				285
> > +#define IMX8MQ_CLK_A53_CORE			285
> > +
> > +#define IMX8MQ_CLK_END				286
> >
> >  #endif /* __DT_BINDINGS_CLOCK_IMX8MQ_H */
> > --
> > 2.16.4
> >