The CPU clock controller plays a general role in the Amlogic A1 SoC
family by generating CPU clocks. As an APB slave module, it offers the
capability to inherit the CPU clock from two sources: the internal fixed
clock known as 'cpu fixed clock' and the external input provided by the
A1 PLL clock controller, referred to as 'syspll'.
It is important for the driver to handle the cpu_clk rate switching
effectively by transitioning to the CPU fixed clock to avoid any
potential execution freezes.
Validation:
* to double-check all clk flags, run the below helper script:
```
pushd /sys/kernel/debug/clk
for f in *; do
if [[ -f "$f/clk_flags" ]]; then
flags="$(cat $f/clk_flags | awk '{$1=$1};1' | sed ':a;N;$!ba;s/\n/ | /g')"
echo -e "$f: $flags"
fi
done
popd
```
* to trace the current clks state, use the
'/sys/kernel/debug/clk/clk_dump' node with jq post-processing:
```
$ cat /sys/kernel/debug/clk/clk_dump | jq '.' > clk_dump.json
```
* to see the CPU clock hierarchy, use the
'/sys/kernel/debug/clk/clk_summary' node with jq post-processing:
```
$ cat /sys/kernel/debug/clk/clk_summary | jq '.' > clk_dump.json
```
when cpu_clk is inherited from sys_pll, it should be:
```
syspll_in 1 1 0 24000000 0 0 50000 Y deviceless no_connection_id
sys_pll 2 2 0 1200000000 0 0 50000 Y deviceless no_connection_id
cpu_clk 1 1 0 1200000000 0 0 50000 Y cpu0 no_connection_id
cpu0 no_connection_id
fd000000.clock-controller dvfs
deviceless no_connection_id
```
and from cpu fixed clock:
```
fclk_div3_div 1 1 0 512000000 0 0 50000 Y deviceless no_connection_id
fclk_div3 4 4 0 512000000 0 0 50000 Y deviceless no_connection_id
cpu_fsource_sel0 1 1 0 512000000 0 0 50000 Y deviceless no_connection_id
cpu_fsource_div0 1 1 0 128000000 0 0 50000 Y deviceless no_connection_id
cpu_fsel0 1 1 0 128000000 0 0 50000 Y deviceless no_connection_id
cpu_fclk 1 1 0 128000000 0 0 50000 Y deviceless no_connection_id
cpu_clk 1 1 0 128000000 0 0 50000 Y cpu0 no_connection_id
cpu0 no_connection_id
fd000000.clock-controller dvfs
deviceless no_connection_id
```
* to debug cpu clk rate propagation and proper parent switching, compile
kernel with the following definition:
$ sed -i "s/undef CLOCK_ALLOW_WRITE_DEBUGFS/define CLOCK_ALLOW_WRITE_DEBUGFS/g" drivers/clk/clk.c
after that, clk_rate debug node for each clock will be available for
write operation
Changes v2 since v1 at [1]:
- introduce new 'INIT_ONCE' flag to eliminate init for already
enabled PLL
- explain why we need to break ABI for a1-pll driver by adding
sys_pll connections
- implement sys_pll init sequence, which is applicable when sys_pll
is disabled
- remove CLK_IS_CRITICAL from sys_pll
- move sys_pll_div16 binding to the end per Rob's suggestion
- add Rob's RvB
- remove holes from the beginning of the cpu clock controller regmap
- move a1-cpu.h registers offsets definition to a1-cpu.c
- set CLK_SET_RATE_GATE for parallel cpu fixed clock source trees
per Martin's and Jerome's suggestion
- redesign clock notifier block from cpu_clk to sys_pll to keep
cpu_clock working continuously (the same implementation is located
in the g12a clock driver)
Links:
[1] https://lore.kernel.org/all/[email protected]/
Dmitry Rokosov (7):
clk: meson: introduce 'INIT_ONCE' flag to eliminate init for enabled
PLL
dt-bindings: clock: meson: a1: pll: introduce new syspll bindings
clk: meson: a1: pll: support 'syspll' general-purpose PLL for CPU
clock
dt-bindings: clock: meson: a1: peripherals: support sys_pll_div16
input
clk: meson: a1: peripherals: support 'sys_pll_div16' clock as GEN
input
dt-bindings: clock: meson: add A1 CPU clock controller bindings
clk: meson: a1: add Amlogic A1 CPU clock controller driver
.../bindings/clock/amlogic,a1-cpu-clkc.yaml | 64 ++++
.../clock/amlogic,a1-peripherals-clkc.yaml | 7 +-
.../bindings/clock/amlogic,a1-pll-clkc.yaml | 7 +-
drivers/clk/meson/Kconfig | 10 +
drivers/clk/meson/Makefile | 1 +
drivers/clk/meson/a1-cpu.c | 331 ++++++++++++++++++
drivers/clk/meson/a1-peripherals.c | 4 +-
drivers/clk/meson/a1-pll.c | 79 +++++
drivers/clk/meson/a1-pll.h | 6 +
drivers/clk/meson/clk-pll.c | 37 +-
drivers/clk/meson/clk-pll.h | 1 +
.../dt-bindings/clock/amlogic,a1-cpu-clkc.h | 19 +
.../dt-bindings/clock/amlogic,a1-pll-clkc.h | 2 +
13 files changed, 546 insertions(+), 22 deletions(-)
create mode 100644 Documentation/devicetree/bindings/clock/amlogic,a1-cpu-clkc.yaml
create mode 100644 drivers/clk/meson/a1-cpu.c
create mode 100644 include/dt-bindings/clock/amlogic,a1-cpu-clkc.h
--
2.43.0
The 'syspll' PLL, also known as the system PLL, is a general and
essential PLL responsible for generating the CPU clock frequency.
With its wide-ranging capabilities, it is designed to accommodate
frequencies within the range of 768MHz to 1536MHz.
Signed-off-by: Dmitry Rokosov <[email protected]>
---
drivers/clk/meson/a1-pll.c | 79 ++++++++++++++++++++++++++++++++++++++
drivers/clk/meson/a1-pll.h | 6 +++
2 files changed, 85 insertions(+)
diff --git a/drivers/clk/meson/a1-pll.c b/drivers/clk/meson/a1-pll.c
index 60b2e53e7e51..af47ba308bbe 100644
--- a/drivers/clk/meson/a1-pll.c
+++ b/drivers/clk/meson/a1-pll.c
@@ -138,6 +138,82 @@ static struct clk_regmap hifi_pll = {
},
};
+static const struct pll_mult_range sys_pll_mult_range = {
+ .min = 32,
+ .max = 64,
+};
+
+static const struct reg_sequence sys_pll_init_regs[] = {
+ { .reg = ANACTRL_SYSPLL_CTRL1, .def = 0x01800000 },
+ { .reg = ANACTRL_SYSPLL_CTRL2, .def = 0x00001100 },
+ { .reg = ANACTRL_SYSPLL_CTRL3, .def = 0x10022300 },
+ { .reg = ANACTRL_SYSPLL_CTRL4, .def = 0x00300000 },
+ { .reg = ANACTRL_SYSPLL_CTRL0, .def = 0x01f18432 },
+};
+
+static struct clk_regmap sys_pll = {
+ .data = &(struct meson_clk_pll_data){
+ .en = {
+ .reg_off = ANACTRL_SYSPLL_CTRL0,
+ .shift = 28,
+ .width = 1,
+ },
+ .m = {
+ .reg_off = ANACTRL_SYSPLL_CTRL0,
+ .shift = 0,
+ .width = 8,
+ },
+ .n = {
+ .reg_off = ANACTRL_SYSPLL_CTRL0,
+ .shift = 10,
+ .width = 5,
+ },
+ .frac = {
+ .reg_off = ANACTRL_SYSPLL_CTRL1,
+ .shift = 0,
+ .width = 19,
+ },
+ .l = {
+ .reg_off = ANACTRL_SYSPLL_STS,
+ .shift = 31,
+ .width = 1,
+ },
+ .current_en = {
+ .reg_off = ANACTRL_SYSPLL_CTRL0,
+ .shift = 26,
+ .width = 1,
+ },
+ .l_detect = {
+ .reg_off = ANACTRL_SYSPLL_CTRL2,
+ .shift = 6,
+ .width = 1,
+ },
+ .range = &sys_pll_mult_range,
+ .init_regs = sys_pll_init_regs,
+ .init_count = ARRAY_SIZE(sys_pll_init_regs),
+ .flags = CLK_MESON_PLL_INIT_ONCE,
+ },
+ .hw.init = &(struct clk_init_data){
+ .name = "sys_pll",
+ .ops = &meson_clk_pll_ops,
+ .parent_names = (const char *[]){ "syspll_in" },
+ .num_parents = 1,
+ },
+};
+
+static struct clk_fixed_factor sys_pll_div16 = {
+ .mult = 1,
+ .div = 16,
+ .hw.init = &(struct clk_init_data){
+ .name = "sys_pll_div16",
+ .ops = &clk_fixed_factor_ops,
+ .parent_hws = (const struct clk_hw *[]) {
+ &sys_pll.hw
+ },
+ .num_parents = 1,
+ },
+};
+
static struct clk_fixed_factor fclk_div2_div = {
.mult = 1,
.div = 2,
@@ -283,6 +359,8 @@ static struct clk_hw *a1_pll_hw_clks[] = {
[CLKID_FCLK_DIV5] = &fclk_div5.hw,
[CLKID_FCLK_DIV7] = &fclk_div7.hw,
[CLKID_HIFI_PLL] = &hifi_pll.hw,
+ [CLKID_SYS_PLL] = &sys_pll.hw,
+ [CLKID_SYS_PLL_DIV16] = &sys_pll_div16.hw,
};
static struct clk_regmap *const a1_pll_regmaps[] = {
@@ -293,6 +371,7 @@ static struct clk_regmap *const a1_pll_regmaps[] = {
&fclk_div5,
&fclk_div7,
&hifi_pll,
+ &sys_pll,
};
static struct regmap_config a1_pll_regmap_cfg = {
diff --git a/drivers/clk/meson/a1-pll.h b/drivers/clk/meson/a1-pll.h
index 4be17b2bf383..666d9b2137e9 100644
--- a/drivers/clk/meson/a1-pll.h
+++ b/drivers/clk/meson/a1-pll.h
@@ -18,6 +18,12 @@
#define ANACTRL_FIXPLL_CTRL0 0x0
#define ANACTRL_FIXPLL_CTRL1 0x4
#define ANACTRL_FIXPLL_STS 0x14
+#define ANACTRL_SYSPLL_CTRL0 0x80
+#define ANACTRL_SYSPLL_CTRL1 0x84
+#define ANACTRL_SYSPLL_CTRL2 0x88
+#define ANACTRL_SYSPLL_CTRL3 0x8c
+#define ANACTRL_SYSPLL_CTRL4 0x90
+#define ANACTRL_SYSPLL_STS 0x94
#define ANACTRL_HIFIPLL_CTRL0 0xc0
#define ANACTRL_HIFIPLL_CTRL1 0xc4
#define ANACTRL_HIFIPLL_CTRL2 0xc8
--
2.43.0
Add the documentation and dt bindings for Amlogic A1 CPU clock
controller.
This controller consists of the general 'cpu_clk' and two main parents:
'cpu fixed clock' and 'syspll'. The 'cpu fixed clock' is an internal
fixed clock, while the 'syspll' serves as an external input from the A1
PLL clock controller.
Signed-off-by: Dmitry Rokosov <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
---
.../bindings/clock/amlogic,a1-cpu-clkc.yaml | 64 +++++++++++++++++++
.../dt-bindings/clock/amlogic,a1-cpu-clkc.h | 19 ++++++
2 files changed, 83 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/amlogic,a1-cpu-clkc.yaml
create mode 100644 include/dt-bindings/clock/amlogic,a1-cpu-clkc.h
diff --git a/Documentation/devicetree/bindings/clock/amlogic,a1-cpu-clkc.yaml b/Documentation/devicetree/bindings/clock/amlogic,a1-cpu-clkc.yaml
new file mode 100644
index 000000000000..f4958b315ed4
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/amlogic,a1-cpu-clkc.yaml
@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/amlogic,a1-cpu-clkc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Amlogic A1 CPU Clock Control Unit
+
+maintainers:
+ - Neil Armstrong <[email protected]>
+ - Jerome Brunet <[email protected]>
+ - Dmitry Rokosov <[email protected]>
+
+properties:
+ compatible:
+ const: amlogic,a1-cpu-clkc
+
+ '#clock-cells':
+ const: 1
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: input fixed pll div2
+ - description: input fixed pll div3
+ - description: input sys pll
+ - description: input oscillator (usually at 24MHz)
+
+ clock-names:
+ items:
+ - const: fclk_div2
+ - const: fclk_div3
+ - const: sys_pll
+ - const: xtal
+
+required:
+ - compatible
+ - '#clock-cells'
+ - reg
+ - clocks
+ - clock-names
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/amlogic,a1-pll-clkc.h>
+ apb {
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ clock-controller@fd000000 {
+ compatible = "amlogic,a1-cpu-clkc";
+ reg = <0 0xfd000080 0 0x8>;
+ #clock-cells = <1>;
+ clocks = <&clkc_pll CLKID_FCLK_DIV2>,
+ <&clkc_pll CLKID_FCLK_DIV3>,
+ <&clkc_pll CLKID_SYS_PLL>,
+ <&xtal>;
+ clock-names = "fclk_div2", "fclk_div3", "sys_pll", "xtal";
+ };
+ };
diff --git a/include/dt-bindings/clock/amlogic,a1-cpu-clkc.h b/include/dt-bindings/clock/amlogic,a1-cpu-clkc.h
new file mode 100644
index 000000000000..1d321c6eddb7
--- /dev/null
+++ b/include/dt-bindings/clock/amlogic,a1-cpu-clkc.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause */
+/*
+ * Copyright (c) 2024, SaluteDevices. All Rights Reserved.
+ * Author: Dmitry Rokosov <[email protected]>
+ */
+
+#ifndef __A1_CPU_CLKC_H
+#define __A1_CPU_CLKC_H
+
+#define CLKID_CPU_FSOURCE_SEL0 0
+#define CLKID_CPU_FSOURCE_DIV0 1
+#define CLKID_CPU_FSEL0 2
+#define CLKID_CPU_FSOURCE_SEL1 3
+#define CLKID_CPU_FSOURCE_DIV1 4
+#define CLKID_CPU_FSEL1 5
+#define CLKID_CPU_FCLK 6
+#define CLKID_CPU_CLK 7
+
+#endif /* __A1_CPU_CLKC_H */
--
2.43.0
The CPU clock controller plays a general role in the Amlogic A1 SoC
family by generating CPU clocks. As an APB slave module, it offers the
capability to inherit the CPU clock from two sources: the internal fixed
clock known as 'cpu fixed clock' and the external input provided by the
A1 PLL clock controller, referred to as 'syspll'.
It is important for the driver to handle cpu_clk rate switching
effectively by transitioning to the CPU fixed clock to avoid any
potential execution freezes.
Signed-off-by: Dmitry Rokosov <[email protected]>
---
drivers/clk/meson/Kconfig | 10 ++
drivers/clk/meson/Makefile | 1 +
drivers/clk/meson/a1-cpu.c | 331 +++++++++++++++++++++++++++++++++++++
3 files changed, 342 insertions(+)
create mode 100644 drivers/clk/meson/a1-cpu.c
diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
index 80c4a18c83d2..148d4495eee3 100644
--- a/drivers/clk/meson/Kconfig
+++ b/drivers/clk/meson/Kconfig
@@ -111,6 +111,16 @@ config COMMON_CLK_AXG_AUDIO
Support for the audio clock controller on AmLogic A113D devices,
aka axg, Say Y if you want audio subsystem to work.
+config COMMON_CLK_A1_CPU
+ tristate "Amlogic A1 SoC CPU controller support"
+ depends on ARM64
+ select COMMON_CLK_MESON_REGMAP
+ select COMMON_CLK_MESON_CLKC_UTILS
+ help
+ Support for the CPU clock controller on Amlogic A113L based
+ device, A1 SoC Family. Say Y if you want A1 CPU clock controller
+ to work.
+
config COMMON_CLK_A1_PLL
tristate "Amlogic A1 SoC PLL controller support"
depends on ARM64
diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
index 4968fc7ad555..2a06eb0303d6 100644
--- a/drivers/clk/meson/Makefile
+++ b/drivers/clk/meson/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_COMMON_CLK_MESON_AUDIO_RSTC) += meson-audio-rstc.o
obj-$(CONFIG_COMMON_CLK_AXG) += axg.o axg-aoclk.o
obj-$(CONFIG_COMMON_CLK_AXG_AUDIO) += axg-audio.o
+obj-$(CONFIG_COMMON_CLK_A1_CPU) += a1-cpu.o
obj-$(CONFIG_COMMON_CLK_A1_PLL) += a1-pll.o
obj-$(CONFIG_COMMON_CLK_A1_PERIPHERALS) += a1-peripherals.o
obj-$(CONFIG_COMMON_CLK_A1_AUDIO) += a1-audio.o
diff --git a/drivers/clk/meson/a1-cpu.c b/drivers/clk/meson/a1-cpu.c
new file mode 100644
index 000000000000..a9edabeafea9
--- /dev/null
+++ b/drivers/clk/meson/a1-cpu.c
@@ -0,0 +1,331 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Amlogic A1 SoC family CPU Clock Controller driver.
+ *
+ * Copyright (c) 2024, SaluteDevices. All Rights Reserved.
+ * Author: Dmitry Rokosov <[email protected]>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include "clk-regmap.h"
+#include "meson-clkc-utils.h"
+
+#include <dt-bindings/clock/amlogic,a1-cpu-clkc.h>
+
+/* CPU Clock Controller register offset */
+#define CPUCTRL_CLK_CTRL0 0x0
+#define CPUCTRL_CLK_CTRL1 0x4
+
+static u32 cpu_fsource_sel_table[] = { 0, 1, 2 };
+static const struct clk_parent_data cpu_fsource_sel_parents[] = {
+ { .fw_name = "xtal" },
+ { .fw_name = "fclk_div2" },
+ { .fw_name = "fclk_div3" },
+};
+
+static struct clk_regmap cpu_fsource_sel0 = {
+ .data = &(struct clk_regmap_mux_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .mask = 0x3,
+ .shift = 0,
+ .table = cpu_fsource_sel_table,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fsource_sel0",
+ .ops = &clk_regmap_mux_ops,
+ .parent_data = cpu_fsource_sel_parents,
+ .num_parents = ARRAY_SIZE(cpu_fsource_sel_parents),
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_fsource_div0 = {
+ .data = &(struct clk_regmap_div_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .shift = 4,
+ .width = 6,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fsource_div0",
+ .ops = &clk_regmap_divider_ops,
+ .parent_hws = (const struct clk_hw *[]) {
+ &cpu_fsource_sel0.hw
+ },
+ .num_parents = 1,
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_fsel0 = {
+ .data = &(struct clk_regmap_mux_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .mask = 0x1,
+ .shift = 2,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fsel0",
+ .ops = &clk_regmap_mux_ops,
+ .parent_hws = (const struct clk_hw *[]) {
+ &cpu_fsource_sel0.hw,
+ &cpu_fsource_div0.hw,
+ },
+ .num_parents = 2,
+ .flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_fsource_sel1 = {
+ .data = &(struct clk_regmap_mux_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .mask = 0x3,
+ .shift = 16,
+ .table = cpu_fsource_sel_table,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fsource_sel1",
+ .ops = &clk_regmap_mux_ops,
+ .parent_data = cpu_fsource_sel_parents,
+ .num_parents = ARRAY_SIZE(cpu_fsource_sel_parents),
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_fsource_div1 = {
+ .data = &(struct clk_regmap_div_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .shift = 20,
+ .width = 6,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fsource_div1",
+ .ops = &clk_regmap_divider_ops,
+ .parent_hws = (const struct clk_hw *[]) {
+ &cpu_fsource_sel1.hw
+ },
+ .num_parents = 1,
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_fsel1 = {
+ .data = &(struct clk_regmap_mux_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .mask = 0x1,
+ .shift = 18,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fsel1",
+ .ops = &clk_regmap_mux_ops,
+ .parent_hws = (const struct clk_hw *[]) {
+ &cpu_fsource_sel1.hw,
+ &cpu_fsource_div1.hw,
+ },
+ .num_parents = 2,
+ .flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_fclk = {
+ .data = &(struct clk_regmap_mux_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .mask = 0x1,
+ .shift = 10,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_fclk",
+ .ops = &clk_regmap_mux_ops,
+ .parent_hws = (const struct clk_hw *[]) {
+ &cpu_fsel0.hw,
+ &cpu_fsel1.hw,
+ },
+ .num_parents = 2,
+ .flags = CLK_SET_RATE_PARENT,
+ },
+};
+
+static struct clk_regmap cpu_clk = {
+ .data = &(struct clk_regmap_mux_data) {
+ .offset = CPUCTRL_CLK_CTRL0,
+ .mask = 0x1,
+ .shift = 11,
+ },
+ .hw.init = &(struct clk_init_data) {
+ .name = "cpu_clk",
+ .ops = &clk_regmap_mux_ops,
+ .parent_data = (const struct clk_parent_data []) {
+ { .hw = &cpu_fclk.hw },
+ { .fw_name = "sys_pll", },
+ },
+ .num_parents = 2,
+ .flags = CLK_SET_RATE_PARENT | CLK_IS_CRITICAL,
+ },
+};
+
+/* Array of all clocks registered by this provider */
+static struct clk_hw *a1_cpu_hw_clks[] = {
+ [CLKID_CPU_FSOURCE_SEL0] = &cpu_fsource_sel0.hw,
+ [CLKID_CPU_FSOURCE_DIV0] = &cpu_fsource_div0.hw,
+ [CLKID_CPU_FSEL0] = &cpu_fsel0.hw,
+ [CLKID_CPU_FSOURCE_SEL1] = &cpu_fsource_sel1.hw,
+ [CLKID_CPU_FSOURCE_DIV1] = &cpu_fsource_div1.hw,
+ [CLKID_CPU_FSEL1] = &cpu_fsel1.hw,
+ [CLKID_CPU_FCLK] = &cpu_fclk.hw,
+ [CLKID_CPU_CLK] = &cpu_clk.hw,
+};
+
+static struct clk_regmap *const a1_cpu_regmaps[] = {
+ &cpu_fsource_sel0,
+ &cpu_fsource_div0,
+ &cpu_fsel0,
+ &cpu_fsource_sel1,
+ &cpu_fsource_div1,
+ &cpu_fsel1,
+ &cpu_fclk,
+ &cpu_clk,
+};
+
+static struct regmap_config a1_cpu_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = CPUCTRL_CLK_CTRL1,
+};
+
+static struct meson_clk_hw_data a1_cpu_clks = {
+ .hws = a1_cpu_hw_clks,
+ .num = ARRAY_SIZE(a1_cpu_hw_clks),
+};
+
+struct a1_sys_pll_nb_data {
+ struct notifier_block nb;
+ struct clk_hw *cpu_clk;
+ struct clk_hw *cpu_fclk;
+ struct clk *sys_pll;
+};
+
+static int meson_a1_sys_pll_notifier_cb(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct a1_sys_pll_nb_data *nbd;
+ int ret = 0;
+
+ nbd = container_of(nb, struct a1_sys_pll_nb_data, nb);
+
+ switch (event) {
+ case PRE_RATE_CHANGE:
+ /*
+ * Clock sys_pll will be changed to feed cpu_clk,
+ * configure cpu_clk to use cpu_fclk fixed clock.
+ */
+ ret = clk_hw_set_parent(nbd->cpu_clk, nbd->cpu_fclk);
+
+ /* Wait for clock propagation */
+ if (!ret)
+ udelay(100);
+
+ break;
+
+ case POST_RATE_CHANGE:
+ /*
+ * Clock sys_pll rate has ben calculated,
+ * switch back cpu_clk to sys_pll
+ */
+ ret = clk_set_parent(nbd->cpu_clk->clk, nbd->sys_pll);
+
+ /* Wait for clock propagation */
+ if (!ret)
+ udelay(100);
+ break;
+
+ default:
+ pr_warn("Unknown event %lu for sys_pll notifier\n", event);
+ break;
+ }
+
+ return notifier_from_errno(ret);
+}
+
+static struct a1_sys_pll_nb_data a1_sys_pll_nb_data = {
+ .nb.notifier_call = meson_a1_sys_pll_notifier_cb,
+ .cpu_clk = &cpu_clk.hw,
+ .cpu_fclk = &cpu_fclk.hw,
+};
+
+static int meson_a1_dvfs_setup(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct clk *sys_pll;
+ int ret;
+
+ /* Setup clock notifier for sys_pll clk */
+ sys_pll = devm_clk_get(dev, "sys_pll");
+ if (IS_ERR(sys_pll))
+ return dev_err_probe(dev, PTR_ERR(sys_pll),
+ "can't get sys_pll as notifier clock\n");
+
+ a1_sys_pll_nb_data.sys_pll = sys_pll;
+ ret = devm_clk_notifier_register(dev, sys_pll,
+ &a1_sys_pll_nb_data.nb);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "can't register sys_pll notifier\n");
+
+ return ret;
+}
+
+static int meson_a1_cpu_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ void __iomem *base;
+ struct regmap *map;
+ int clkid, i, err;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return dev_err_probe(dev, PTR_ERR(base),
+ "can't ioremap resource\n");
+
+ map = devm_regmap_init_mmio(dev, base, &a1_cpu_regmap_cfg);
+ if (IS_ERR(map))
+ return dev_err_probe(dev, PTR_ERR(map),
+ "can't init regmap mmio region\n");
+
+ /* Populate regmap for the regmap backed clocks */
+ for (i = 0; i < ARRAY_SIZE(a1_cpu_regmaps); i++)
+ a1_cpu_regmaps[i]->map = map;
+
+ for (clkid = 0; clkid < a1_cpu_clks.num; clkid++) {
+ err = devm_clk_hw_register(dev, a1_cpu_clks.hws[clkid]);
+ if (err)
+ return dev_err_probe(dev, err,
+ "clock[%d] registration failed\n",
+ clkid);
+ }
+
+ err = devm_of_clk_add_hw_provider(dev, meson_clk_hw_get, &a1_cpu_clks);
+ if (err)
+ return dev_err_probe(dev, err, "can't add clk hw provider\n");
+
+ return meson_a1_dvfs_setup(pdev);
+}
+
+static const struct of_device_id a1_cpu_clkc_match_table[] = {
+ { .compatible = "amlogic,a1-cpu-clkc", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, a1_cpu_clkc_match_table);
+
+static struct platform_driver a1_cpu_clkc_driver = {
+ .probe = meson_a1_cpu_probe,
+ .driver = {
+ .name = "a1-cpu-clkc",
+ .of_match_table = a1_cpu_clkc_match_table,
+ },
+};
+
+module_platform_driver(a1_cpu_clkc_driver);
+MODULE_AUTHOR("Dmitry Rokosov <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.43.0
The clock 'sys_pll_div16' is one of the parents of the GEN clock. It is
generated in the A1 PLL clock controller with a fixed factor.
Signed-off-by: Dmitry Rokosov <[email protected]>
---
drivers/clk/meson/a1-peripherals.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/meson/a1-peripherals.c b/drivers/clk/meson/a1-peripherals.c
index 621af1e6e4b2..3c4452f2b146 100644
--- a/drivers/clk/meson/a1-peripherals.c
+++ b/drivers/clk/meson/a1-peripherals.c
@@ -747,13 +747,13 @@ static struct clk_regmap fclk_div2_divn = {
};
/*
- * the index 2 is sys_pll_div16, it will be implemented in the CPU clock driver,
* the index 4 is the clock measurement source, it's not supported yet
*/
-static u32 gen_table[] = { 0, 1, 3, 5, 6, 7, 8 };
+static u32 gen_table[] = { 0, 1, 2, 3, 5, 6, 7, 8 };
static const struct clk_parent_data gen_parent_data[] = {
{ .fw_name = "xtal", },
{ .hw = &rtc.hw },
+ { .fw_name = "sys_pll_div16", },
{ .fw_name = "hifi_pll", },
{ .fw_name = "fclk_div2", },
{ .fw_name = "fclk_div3", },
--
2.43.0
On Fri 10 May 2024 at 12:08, Dmitry Rokosov <[email protected]> wrote:
> The 'syspll' PLL, also known as the system PLL, is a general and
> essential PLL responsible for generating the CPU clock frequency.
> With its wide-ranging capabilities, it is designed to accommodate
> frequencies within the range of 768MHz to 1536MHz.
>
> Signed-off-by: Dmitry Rokosov <[email protected]>
> ---
> drivers/clk/meson/a1-pll.c | 79 ++++++++++++++++++++++++++++++++++++++
> drivers/clk/meson/a1-pll.h | 6 +++
> 2 files changed, 85 insertions(+)
>
> diff --git a/drivers/clk/meson/a1-pll.c b/drivers/clk/meson/a1-pll.c
> index 60b2e53e7e51..af47ba308bbe 100644
> --- a/drivers/clk/meson/a1-pll.c
> +++ b/drivers/clk/meson/a1-pll.c
> @@ -138,6 +138,82 @@ static struct clk_regmap hifi_pll = {
> },
> };
>
> +static const struct pll_mult_range sys_pll_mult_range = {
> + .min = 32,
> + .max = 64,
> +};
> +
> +static const struct reg_sequence sys_pll_init_regs[] = {
> + { .reg = ANACTRL_SYSPLL_CTRL1, .def = 0x01800000 },
> + { .reg = ANACTRL_SYSPLL_CTRL2, .def = 0x00001100 },
> + { .reg = ANACTRL_SYSPLL_CTRL3, .def = 0x10022300 },
> + { .reg = ANACTRL_SYSPLL_CTRL4, .def = 0x00300000 },
> + { .reg = ANACTRL_SYSPLL_CTRL0, .def = 0x01f18432 },
> +};
> +
> +static struct clk_regmap sys_pll = {
> + .data = &(struct meson_clk_pll_data){
> + .en = {
> + .reg_off = ANACTRL_SYSPLL_CTRL0,
> + .shift = 28,
> + .width = 1,
> + },
> + .m = {
> + .reg_off = ANACTRL_SYSPLL_CTRL0,
> + .shift = 0,
> + .width = 8,
> + },
> + .n = {
> + .reg_off = ANACTRL_SYSPLL_CTRL0,
> + .shift = 10,
> + .width = 5,
> + },
> + .frac = {
> + .reg_off = ANACTRL_SYSPLL_CTRL1,
> + .shift = 0,
> + .width = 19,
> + },
> + .l = {
> + .reg_off = ANACTRL_SYSPLL_STS,
> + .shift = 31,
> + .width = 1,
> + },
> + .current_en = {
> + .reg_off = ANACTRL_SYSPLL_CTRL0,
> + .shift = 26,
> + .width = 1,
> + },
> + .l_detect = {
> + .reg_off = ANACTRL_SYSPLL_CTRL2,
> + .shift = 6,
> + .width = 1,
> + },
> + .range = &sys_pll_mult_range,
> + .init_regs = sys_pll_init_regs,
> + .init_count = ARRAY_SIZE(sys_pll_init_regs),
Like other 'fishy' flags, I would like a clear comment why this flag is
required so, 2y from now, we will know why it was put there and how we
can deal with it.
> + .flags = CLK_MESON_PLL_INIT_ONCE,
> + },
> + .hw.init = &(struct clk_init_data){
> + .name = "sys_pll",
> + .ops = &meson_clk_pll_ops,
> + .parent_names = (const char *[]){ "syspll_in" },
> + .num_parents = 1,
> + },
> +};
> +
> +static struct clk_fixed_factor sys_pll_div16 = {
> + .mult = 1,
> + .div = 16,
> + .hw.init = &(struct clk_init_data){
> + .name = "sys_pll_div16",
> + .ops = &clk_fixed_factor_ops,
> + .parent_hws = (const struct clk_hw *[]) {
> + &sys_pll.hw
> + },
> + .num_parents = 1,
> + },
> +};
Unlike the fdivs, this fixed divider is not part of the diagram
describing the syspll clock.
IMO, it could as well be in peripheral controller because it exists
(from what I can see) just testing purposes, to make the sys pll
observable through tst_out or gen_clk.
It also looks less awkward in the bindings.
> +
> static struct clk_fixed_factor fclk_div2_div = {
> .mult = 1,
> .div = 2,
> @@ -283,6 +359,8 @@ static struct clk_hw *a1_pll_hw_clks[] = {
> [CLKID_FCLK_DIV5] = &fclk_div5.hw,
> [CLKID_FCLK_DIV7] = &fclk_div7.hw,
> [CLKID_HIFI_PLL] = &hifi_pll.hw,
> + [CLKID_SYS_PLL] = &sys_pll.hw,
> + [CLKID_SYS_PLL_DIV16] = &sys_pll_div16.hw,
> };
>
> static struct clk_regmap *const a1_pll_regmaps[] = {
> @@ -293,6 +371,7 @@ static struct clk_regmap *const a1_pll_regmaps[] = {
> &fclk_div5,
> &fclk_div7,
> &hifi_pll,
> + &sys_pll,
> };
>
> static struct regmap_config a1_pll_regmap_cfg = {
> diff --git a/drivers/clk/meson/a1-pll.h b/drivers/clk/meson/a1-pll.h
> index 4be17b2bf383..666d9b2137e9 100644
> --- a/drivers/clk/meson/a1-pll.h
> +++ b/drivers/clk/meson/a1-pll.h
> @@ -18,6 +18,12 @@
> #define ANACTRL_FIXPLL_CTRL0 0x0
> #define ANACTRL_FIXPLL_CTRL1 0x4
> #define ANACTRL_FIXPLL_STS 0x14
> +#define ANACTRL_SYSPLL_CTRL0 0x80
> +#define ANACTRL_SYSPLL_CTRL1 0x84
> +#define ANACTRL_SYSPLL_CTRL2 0x88
> +#define ANACTRL_SYSPLL_CTRL3 0x8c
> +#define ANACTRL_SYSPLL_CTRL4 0x90
> +#define ANACTRL_SYSPLL_STS 0x94
> #define ANACTRL_HIFIPLL_CTRL0 0xc0
> #define ANACTRL_HIFIPLL_CTRL1 0xc4
> #define ANACTRL_HIFIPLL_CTRL2 0xc8
--
Jerome
On Mon, May 13, 2024 at 02:48:58PM +0200, Jerome Brunet wrote:
>
> On Fri 10 May 2024 at 12:08, Dmitry Rokosov <[email protected]> wrote:
>
> > The 'syspll' PLL, also known as the system PLL, is a general and
> > essential PLL responsible for generating the CPU clock frequency.
> > With its wide-ranging capabilities, it is designed to accommodate
> > frequencies within the range of 768MHz to 1536MHz.
> >
> > Signed-off-by: Dmitry Rokosov <[email protected]>
> > ---
> > drivers/clk/meson/a1-pll.c | 79 ++++++++++++++++++++++++++++++++++++++
> > drivers/clk/meson/a1-pll.h | 6 +++
> > 2 files changed, 85 insertions(+)
> >
> > diff --git a/drivers/clk/meson/a1-pll.c b/drivers/clk/meson/a1-pll.c
> > index 60b2e53e7e51..af47ba308bbe 100644
> > --- a/drivers/clk/meson/a1-pll.c
> > +++ b/drivers/clk/meson/a1-pll.c
> > @@ -138,6 +138,82 @@ static struct clk_regmap hifi_pll = {
> > },
> > };
> >
> > +static const struct pll_mult_range sys_pll_mult_range = {
> > + .min = 32,
> > + .max = 64,
> > +};
> > +
> > +static const struct reg_sequence sys_pll_init_regs[] = {
> > + { .reg = ANACTRL_SYSPLL_CTRL1, .def = 0x01800000 },
> > + { .reg = ANACTRL_SYSPLL_CTRL2, .def = 0x00001100 },
> > + { .reg = ANACTRL_SYSPLL_CTRL3, .def = 0x10022300 },
> > + { .reg = ANACTRL_SYSPLL_CTRL4, .def = 0x00300000 },
> > + { .reg = ANACTRL_SYSPLL_CTRL0, .def = 0x01f18432 },
> > +};
> > +
> > +static struct clk_regmap sys_pll = {
> > + .data = &(struct meson_clk_pll_data){
> > + .en = {
> > + .reg_off = ANACTRL_SYSPLL_CTRL0,
> > + .shift = 28,
> > + .width = 1,
> > + },
> > + .m = {
> > + .reg_off = ANACTRL_SYSPLL_CTRL0,
> > + .shift = 0,
> > + .width = 8,
> > + },
> > + .n = {
> > + .reg_off = ANACTRL_SYSPLL_CTRL0,
> > + .shift = 10,
> > + .width = 5,
> > + },
> > + .frac = {
> > + .reg_off = ANACTRL_SYSPLL_CTRL1,
> > + .shift = 0,
> > + .width = 19,
> > + },
> > + .l = {
> > + .reg_off = ANACTRL_SYSPLL_STS,
> > + .shift = 31,
> > + .width = 1,
> > + },
> > + .current_en = {
> > + .reg_off = ANACTRL_SYSPLL_CTRL0,
> > + .shift = 26,
> > + .width = 1,
> > + },
> > + .l_detect = {
> > + .reg_off = ANACTRL_SYSPLL_CTRL2,
> > + .shift = 6,
> > + .width = 1,
> > + },
> > + .range = &sys_pll_mult_range,
> > + .init_regs = sys_pll_init_regs,
> > + .init_count = ARRAY_SIZE(sys_pll_init_regs),
>
> Like other 'fishy' flags, I would like a clear comment why this flag is
> required so, 2y from now, we will know why it was put there and how we
> can deal with it.
>
Yep, you are totally correct. The proper comment is required for that.
> > + .flags = CLK_MESON_PLL_INIT_ONCE,
> > + },
> > + .hw.init = &(struct clk_init_data){
> > + .name = "sys_pll",
> > + .ops = &meson_clk_pll_ops,
> > + .parent_names = (const char *[]){ "syspll_in" },
> > + .num_parents = 1,
> > + },
> > +};
> > +
> > +static struct clk_fixed_factor sys_pll_div16 = {
> > + .mult = 1,
> > + .div = 16,
> > + .hw.init = &(struct clk_init_data){
> > + .name = "sys_pll_div16",
> > + .ops = &clk_fixed_factor_ops,
> > + .parent_hws = (const struct clk_hw *[]) {
> > + &sys_pll.hw
> > + },
> > + .num_parents = 1,
> > + },
> > +};
>
> Unlike the fdivs, this fixed divider is not part of the diagram
> describing the syspll clock.
>
> IMO, it could as well be in peripheral controller because it exists
> (from what I can see) just testing purposes, to make the sys pll
> observable through tst_out or gen_clk.
>
> It also looks less awkward in the bindings.
>
In any case, it is necessary to introduce a new connection. Instead of
using 'sys_pll_div16', it will now be called 'sys_pll'. I agree with you
that this change will make the code more elegant.
> > +
> > static struct clk_fixed_factor fclk_div2_div = {
> > .mult = 1,
> > .div = 2,
> > @@ -283,6 +359,8 @@ static struct clk_hw *a1_pll_hw_clks[] = {
> > [CLKID_FCLK_DIV5] = &fclk_div5.hw,
> > [CLKID_FCLK_DIV7] = &fclk_div7.hw,
> > [CLKID_HIFI_PLL] = &hifi_pll.hw,
> > + [CLKID_SYS_PLL] = &sys_pll.hw,
> > + [CLKID_SYS_PLL_DIV16] = &sys_pll_div16.hw,
> > };
> >
> > static struct clk_regmap *const a1_pll_regmaps[] = {
> > @@ -293,6 +371,7 @@ static struct clk_regmap *const a1_pll_regmaps[] = {
> > &fclk_div5,
> > &fclk_div7,
> > &hifi_pll,
> > + &sys_pll,
> > };
> >
> > static struct regmap_config a1_pll_regmap_cfg = {
> > diff --git a/drivers/clk/meson/a1-pll.h b/drivers/clk/meson/a1-pll.h
> > index 4be17b2bf383..666d9b2137e9 100644
> > --- a/drivers/clk/meson/a1-pll.h
> > +++ b/drivers/clk/meson/a1-pll.h
> > @@ -18,6 +18,12 @@
> > #define ANACTRL_FIXPLL_CTRL0 0x0
> > #define ANACTRL_FIXPLL_CTRL1 0x4
> > #define ANACTRL_FIXPLL_STS 0x14
> > +#define ANACTRL_SYSPLL_CTRL0 0x80
> > +#define ANACTRL_SYSPLL_CTRL1 0x84
> > +#define ANACTRL_SYSPLL_CTRL2 0x88
> > +#define ANACTRL_SYSPLL_CTRL3 0x8c
> > +#define ANACTRL_SYSPLL_CTRL4 0x90
> > +#define ANACTRL_SYSPLL_STS 0x94
> > #define ANACTRL_HIFIPLL_CTRL0 0xc0
> > #define ANACTRL_HIFIPLL_CTRL1 0xc4
> > #define ANACTRL_HIFIPLL_CTRL2 0xc8
>
>
> --
> Jerome
--
Thank you,
Dmitry