2020-01-14 07:28:15

by Peng Fan

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

From: Peng Fan <[email protected]>

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


2020-01-14 07:28:26

by Peng Fan

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

From: Peng Fan <[email protected]>

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 <[email protected]>
Signed-off-by: Peng Fan <[email protected]>
---

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

2020-01-14 07:28:37

by Peng Fan

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

From: Peng Fan <[email protected]>

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 <[email protected]>
Signed-off-by: Peng Fan <[email protected]>
---

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

2020-01-14 07:28:42

by Peng Fan

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

From: Peng Fan <[email protected]>

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 <[email protected]>
Signed-off-by: Peng Fan <[email protected]>
---

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

2020-01-14 07:29:30

by Peng Fan

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

From: Peng Fan <[email protected]>

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 <[email protected]>
Signed-off-by: Peng Fan <[email protected]>
---

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

2020-02-12 13:43:40

by Shawn Guo

[permalink] [raw]
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 <[email protected]>

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 <[email protected]>
> Signed-off-by: Peng Fan <[email protected]>
> ---
>
> 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
>

2020-02-12 13:48:38

by Peng Fan

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

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 <[email protected]>
>
> 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 <[email protected]>
> > Signed-off-by: Peng Fan <[email protected]>
> > ---
> >
> > 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
> >