[PATCH v6 0/2] CLK: microchip: Add clkcfg driver for Microchip PolarFire SoC

[PATCH v6 0/2] CLK: microchip: Add clkcfg driver for Microchip PolarFire SoC

[conor.dooley]

From: Conor Dooley <conor.dooley@microchip.com>

This patchset adds support for the Microchip PolarFire clkcfg
hardware block.

Changes since v5:
* Dropped clock-output-names property

Major changes since v4:
* Adjusted license for microchip,mpfs-clock.h to match microchip,mpfs.yaml
* Corrected the number of clocks to 33 from 32

Major changes since v3:
* Patch reformatted so microchip,mpfs-clock.h is part of device-tree patch

Major changes since v2:
* In mpfs_cfg_clk_set_rate, return immediately if divider_get_val
    returns <0 
* rebased to v5.12-rc1

Major changes since v1:
 * Dependency on SOC_MICROCHIP_POLARFIRE
 * All references to PFSOC/pfsoc changed to MPFS/mpfs
 * Cleaned error handling in _probe
 * Re-ordered code to place structs et al at top

Daire McNamara (2):
  dt-bindings: clk: microchip: Add Microchip PolarFire host binding
  clk: microchip: Add driver for Microchip PolarFire SoC

 .../bindings/clock/microchip,mpfs.yaml        |  58 +++
 drivers/clk/Kconfig                           |   1 +
 drivers/clk/Makefile                          |   2 +-
 drivers/clk/microchip/Kconfig                 |   7 +
 drivers/clk/microchip/Makefile                |   6 +-
 drivers/clk/microchip/clk-mpfs.c              | 444 ++++++++++++++++++
 .../dt-bindings/clock/microchip,mpfs-clock.h  |  45 ++
 7 files changed, 560 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/microchip,mpfs.yaml
 create mode 100644 drivers/clk/microchip/Kconfig
 create mode 100644 drivers/clk/microchip/clk-mpfs.c
 create mode 100644 include/dt-bindings/clock/microchip,mpfs-clock.h

-- 
2.33.1

[PATCH v6 1/2] dt-bindings: clk: microchip: Add Microchip PolarFire host binding

[conor.dooley]

From: Daire McNamara <daire.mcnamara@microchip.com>

Add device tree bindings for the Microchip PolarFire system
clock controller

Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
 .../bindings/clock/microchip,mpfs.yaml        | 58 +++++++++++++++++++
 .../dt-bindings/clock/microchip,mpfs-clock.h  | 45 ++++++++++++++
 2 files changed, 103 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/clock/microchip,mpfs.yaml
 create mode 100644 include/dt-bindings/clock/microchip,mpfs-clock.h

diff --git a/Documentation/devicetree/bindings/clock/microchip,mpfs.yaml b/Documentation/devicetree/bindings/clock/microchip,mpfs.yaml
new file mode 100644
index 000000000000..0c15afa2214c
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/microchip,mpfs.yaml
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/microchip,mpfs.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip PolarFire Clock Control Module Binding
+
+maintainers:
+  - Daire McNamara <daire.mcnamara@microchip.com>
+
+description: |
+  Microchip PolarFire clock control (CLKCFG) is an integrated clock controller,
+  which gates and enables all peripheral clocks.
+
+  This device tree binding describes 33 gate clocks.  Clocks are referenced by
+  user nodes by the CLKCFG node phandle and the clock index in the group, from
+  0 to 32.
+
+properties:
+  compatible:
+    const: microchip,mpfs-clkcfg
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  '#clock-cells':
+    const: 1
+    description: |
+      The clock consumer should specify the desired clock by having the clock
+      ID in its "clocks" phandle cell. See include/dt-bindings/clock/microchip,mpfs-clock.h
+      for the full list of PolarFire clock IDs.
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - '#clock-cells'
+
+additionalProperties: false
+
+examples:
+  # Clock Config node:
+  - |
+    #include <dt-bindings/clock/microchip,mpfs-clock.h>
+    soc {
+            #address-cells = <2>;
+            #size-cells = <2>;
+            clkcfg: clock-controller@20002000 {
+                compatible = "microchip,mpfs-clkcfg";
+                reg = <0x0 0x20002000 0x0 0x1000>;
+                clocks = <&ref>;
+                #clock-cells = <1>;
+        };
+    };
diff --git a/include/dt-bindings/clock/microchip,mpfs-clock.h b/include/dt-bindings/clock/microchip,mpfs-clock.h
new file mode 100644
index 000000000000..73f2a9324857
--- /dev/null
+++ b/include/dt-bindings/clock/microchip,mpfs-clock.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/*
+ * Daire McNamara,<daire.mcnamara@microchip.com>
+ * Copyright (C) 2020 Microchip Technology Inc.  All rights reserved.
+ */
+
+#ifndef _DT_BINDINGS_CLK_MICROCHIP_MPFS_H_
+#define _DT_BINDINGS_CLK_MICROCHIP_MPFS_H_
+
+#define CLK_CPU		0
+#define CLK_AXI		1
+#define CLK_AHB		2
+
+#define CLK_ENVM	3
+#define CLK_MAC0	4
+#define CLK_MAC1	5
+#define CLK_MMC		6
+#define CLK_TIMER	7
+#define CLK_MMUART0	8
+#define CLK_MMUART1	9
+#define CLK_MMUART2	10
+#define CLK_MMUART3	11
+#define CLK_MMUART4	12
+#define CLK_SPI0	13
+#define CLK_SPI1	14
+#define CLK_I2C0	15
+#define CLK_I2C1	16
+#define CLK_CAN0	17
+#define CLK_CAN1	18
+#define CLK_USB		19
+#define CLK_RESERVED	20
+#define CLK_RTC		21
+#define CLK_QSPI	22
+#define CLK_GPIO0	23
+#define CLK_GPIO1	24
+#define CLK_GPIO2	25
+#define CLK_DDRC	26
+#define CLK_FIC0	27
+#define CLK_FIC1	28
+#define CLK_FIC2	29
+#define CLK_FIC3	30
+#define CLK_ATHENA	31
+#define CLK_CFM		32
+
+#endif	/* _DT_BINDINGS_CLK_MICROCHIP_MPFS_H_ */
-- 
2.33.1

Re: [PATCH v6 1/2] dt-bindings: clk: microchip: Add Microchip PolarFire host binding

[Geert Uytterhoeven]

On Tue, Nov 30, 2021 at 3:06 PM <conor.dooley@microchip.com> wrote:
> From: Daire McNamara <daire.mcnamara@microchip.com>
>
> Add device tree bindings for the Microchip PolarFire system
> clock controller
>
> Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> Reviewed-by: Rob Herring <robh@kernel.org>

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH v6 2/2] clk: microchip: Add driver for Microchip PolarFire SoC

[conor.dooley]

From: Daire McNamara <daire.mcnamara@microchip.com>

Add support for clock configuration on Microchip PolarFire SoC

Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
 drivers/clk/Kconfig              |   1 +
 drivers/clk/Makefile             |   2 +-
 drivers/clk/microchip/Kconfig    |   7 +
 drivers/clk/microchip/Makefile   |   6 +-
 drivers/clk/microchip/clk-mpfs.c | 444 +++++++++++++++++++++++++++++++
 5 files changed, 457 insertions(+), 3 deletions(-)
 create mode 100644 drivers/clk/microchip/Kconfig
 create mode 100644 drivers/clk/microchip/clk-mpfs.c

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index c5b3dc97396a..92d112a40269 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -401,6 +401,7 @@ source "drivers/clk/ingenic/Kconfig"
 source "drivers/clk/keystone/Kconfig"
 source "drivers/clk/mediatek/Kconfig"
 source "drivers/clk/meson/Kconfig"
+source "drivers/clk/microchip/Kconfig"
 source "drivers/clk/mstar/Kconfig"
 source "drivers/clk/mvebu/Kconfig"
 source "drivers/clk/pistachio/Kconfig"
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index e42312121e51..b60471a6061f 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -89,7 +89,7 @@ obj-$(CONFIG_ARCH_KEYSTONE)		+= keystone/
 obj-$(CONFIG_MACH_LOONGSON32)		+= loongson1/
 obj-y					+= mediatek/
 obj-$(CONFIG_ARCH_MESON)		+= meson/
-obj-$(CONFIG_MACH_PIC32)		+= microchip/
+obj-y					+= microchip/
 ifeq ($(CONFIG_COMMON_CLK), y)
 obj-$(CONFIG_ARCH_MMP)			+= mmp/
 endif
diff --git a/drivers/clk/microchip/Kconfig b/drivers/clk/microchip/Kconfig
new file mode 100644
index 000000000000..f5edc7b3c07c
--- /dev/null
+++ b/drivers/clk/microchip/Kconfig
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config MCHP_CLK_MPFS
+	bool "Clk driver for PolarFire SoC"
+	depends on (RISCV && SOC_MICROCHIP_POLARFIRE) || COMPILE_TEST
+	help
+	  Supports Clock Configuration for PolarFire SoC
diff --git a/drivers/clk/microchip/Makefile b/drivers/clk/microchip/Makefile
index f34b247e870f..0dce0b12eac4 100644
--- a/drivers/clk/microchip/Makefile
+++ b/drivers/clk/microchip/Makefile
@@ -1,3 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_COMMON_CLK_PIC32) += clk-core.o
-obj-$(CONFIG_PIC32MZDA) += clk-pic32mzda.o
+
+obj-$(CONFIG_COMMON_CLK_PIC32)	+= clk-core.o
+obj-$(CONFIG_PIC32MZDA)		+= clk-pic32mzda.o
+obj-$(CONFIG_MCHP_CLK_MPFS)	+= clk-mpfs.o
diff --git a/drivers/clk/microchip/clk-mpfs.c b/drivers/clk/microchip/clk-mpfs.c
new file mode 100644
index 000000000000..541f88181877
--- /dev/null
+++ b/drivers/clk/microchip/clk-mpfs.c
@@ -0,0 +1,444 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Daire McNamara,<daire.mcnamara@microchip.com>
+ * Copyright (C) 2020 Microchip Technology Inc.  All rights reserved.
+ */
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <dt-bindings/clock/microchip,mpfs-clock.h>
+
+/* address offset of control registers */
+#define REG_CLOCK_CONFIG_CR	0x08u
+#define REG_SUBBLK_CLOCK_CR	0x84u
+#define REG_SUBBLK_RESET_CR	0x88u
+
+struct mpfs_clock_data {
+	void __iomem *base;
+	struct clk_hw_onecell_data hw_data;
+};
+
+struct mpfs_cfg_clock {
+	unsigned int id;
+	const char *name;
+	u8 shift;
+	u8 width;
+	const struct clk_div_table *table;
+	unsigned long flags;
+};
+
+struct mpfs_cfg_hw_clock {
+	struct mpfs_cfg_clock cfg;
+	void __iomem *sys_base;
+	/* lock is used to prevent multiple writes */
+	spinlock_t *lock;
+	struct clk_hw hw;
+	struct clk_init_data init;
+};
+
+#define to_mpfs_cfg_clk(_hw) container_of(_hw, struct mpfs_cfg_hw_clock, hw)
+
+struct mpfs_periph_clock {
+	unsigned int id;
+	const char *name;
+	u8 shift;
+	unsigned long flags;
+};
+
+struct mpfs_periph_hw_clock {
+	struct mpfs_periph_clock periph;
+	void __iomem *sys_base;
+	/* lock is used to prevent multiple writes */
+	spinlock_t *lock;
+	struct clk_hw hw;
+};
+
+#define to_mpfs_periph_clk(_hw) container_of(_hw, struct mpfs_periph_hw_clock, hw)
+
+/*
+ * mpfs_clk_lock prevents anything else from writing to the
+ * mpfs clk block while a software locked register is being written.
+ */
+static DEFINE_SPINLOCK(mpfs_clk_lock);
+
+static struct clk_parent_data mpfs_cfg_parent[] = {
+	{ .fw_name = "msspllclk", .name = "msspllclk" },
+};
+
+static const struct clk_div_table mpfs_div_cpu_axi_table[] = {
+	{ 0, 1 }, { 1, 2 }, { 2, 4 }, { 3, 8 },
+	{ 0, 0 }
+};
+
+static const struct clk_div_table mpfs_div_ahb_table[] = {
+	{ 1, 2 }, { 2, 4}, { 3, 8 },
+	{ 0, 0 }
+};
+
+static unsigned long mpfs_cfg_clk_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+	struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+	struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
+	void __iomem *base_addr = cfg_hw->sys_base;
+	unsigned long rate;
+	u32 val;
+
+	val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR) >> cfg->shift;
+	val &= clk_div_mask(cfg->width);
+	rate = prate / (1u << val);
+
+	return rate;
+}
+
+static long mpfs_cfg_clk_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate)
+{
+	struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+	struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
+
+	return divider_round_rate(hw, rate, prate, cfg->table, cfg->width, cfg->flags);
+}
+
+static int mpfs_cfg_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
+{
+	struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+	struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
+	void __iomem *base_addr = cfg_hw->sys_base;
+	unsigned long flags = 0;
+	u32 val;
+	int divider_setting;
+
+	divider_setting = divider_get_val(rate, prate, cfg->table, cfg->width, cfg_hw->cfg.flags);
+
+	if (divider_setting < 0)
+		return divider_setting;
+
+	if (cfg_hw->lock)
+		spin_lock_irqsave(cfg_hw->lock, flags);
+	else
+		__acquire(cfg_hw->lock);
+
+	val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR);
+	val &= ~(clk_div_mask(cfg->width) << cfg_hw->cfg.shift);
+	val |= divider_setting << cfg->shift;
+	writel_relaxed(val, base_addr + REG_CLOCK_CONFIG_CR);
+
+	if (cfg_hw->lock)
+		spin_unlock_irqrestore(cfg_hw->lock, flags);
+	else
+		__release(cfg_hw->lock);
+
+	return 0;
+}
+
+static const struct clk_ops mpfs_clk_cfg_ops = {
+	.recalc_rate = mpfs_cfg_clk_recalc_rate,
+	.round_rate = mpfs_cfg_clk_round_rate,
+	.set_rate = mpfs_cfg_clk_set_rate,
+};
+
+#define CLK_CFG(_id, _name, _parent, _shift, _width, _table, _flags) {	\
+		.cfg.id = _id,								\
+		.cfg.name = _name,							\
+		.cfg.shift = _shift,							\
+		.cfg.width = _width,							\
+		.cfg.table = _table,							\
+		.hw.init = CLK_HW_INIT_PARENTS_DATA(_name, _parent, &mpfs_clk_cfg_ops,	\
+						    _flags),				\
+	}
+
+static struct mpfs_cfg_hw_clock mpfs_cfg_clks[] = {
+	CLK_CFG(CLK_CPU, "clk_cpu", mpfs_cfg_parent, 0, 2, mpfs_div_cpu_axi_table, 0),
+	CLK_CFG(CLK_AXI, "clk_axi", mpfs_cfg_parent, 2, 2, mpfs_div_cpu_axi_table, 0),
+	CLK_CFG(CLK_AHB, "clk_ahb", mpfs_cfg_parent, 4, 2, mpfs_div_ahb_table, 0),
+};
+
+static void mpfs_clk_unregister_cfg(struct device *dev, struct clk_hw *hw)
+{
+	struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
+
+	devm_clk_hw_unregister(dev, hw);
+	kfree(cfg_hw);
+}
+
+static struct clk_hw *mpfs_clk_register_cfg(struct device *dev,
+					    struct mpfs_cfg_hw_clock *cfg_hw,
+					    void __iomem *sys_base)
+{
+	struct clk_hw *hw;
+	int err;
+
+	cfg_hw->sys_base = sys_base;
+	cfg_hw->lock = &mpfs_clk_lock;
+
+	hw = &cfg_hw->hw;
+	err = devm_clk_hw_register(dev, hw);
+	if (err)
+		return ERR_PTR(err);
+
+	return hw;
+}
+
+static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
+				  int num_clks, struct mpfs_clock_data *data)
+{
+	struct clk_hw *hw;
+	void __iomem *sys_base = data->base;
+	unsigned int i, id;
+
+	for (i = 0; i < num_clks; i++) {
+		struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
+
+		hw = mpfs_clk_register_cfg(dev, cfg_hw, sys_base);
+		if (IS_ERR(hw)) {
+			dev_err(dev, "%s: failed to register clock %s\n", __func__,
+				cfg_hw->cfg.name);
+			goto err_clk;
+		}
+
+		id = cfg_hws[i].cfg.id;
+		data->hw_data.hws[id] = hw;
+	}
+
+	return 0;
+
+err_clk:
+	while (i--)
+		mpfs_clk_unregister_cfg(dev, data->hw_data.hws[cfg_hws[i].cfg.id]);
+
+	return PTR_ERR(hw);
+}
+
+static int mpfs_periph_clk_enable(struct clk_hw *hw)
+{
+	struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+	struct mpfs_periph_clock *periph = &periph_hw->periph;
+	void __iomem *base_addr = periph_hw->sys_base;
+	u32 reg, val;
+
+	reg = readl_relaxed(base_addr + REG_SUBBLK_RESET_CR);
+	val = reg & ~(1u << periph->shift);
+	writel_relaxed(val, base_addr + REG_SUBBLK_RESET_CR);
+
+	reg = readl_relaxed(base_addr + REG_SUBBLK_CLOCK_CR);
+	val = reg | (1u << periph->shift);
+	writel_relaxed(val, base_addr + REG_SUBBLK_CLOCK_CR);
+
+	return 0;
+}
+
+static void mpfs_periph_clk_disable(struct clk_hw *hw)
+{
+	struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+	struct mpfs_periph_clock *periph = &periph_hw->periph;
+	void __iomem *base_addr = periph_hw->sys_base;
+	u32 reg, val;
+
+	reg = readl_relaxed(base_addr + REG_SUBBLK_RESET_CR);
+	val = reg | (1u << periph->shift);
+	writel_relaxed(val, base_addr + REG_SUBBLK_RESET_CR);
+
+	reg = readl_relaxed(base_addr + REG_SUBBLK_CLOCK_CR);
+	val = reg & ~(1u << periph->shift);
+	writel_relaxed(val, base_addr + REG_SUBBLK_CLOCK_CR);
+}
+
+static int mpfs_periph_clk_is_enabled(struct clk_hw *hw)
+{
+	struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+	struct mpfs_periph_clock *periph = &periph_hw->periph;
+	void __iomem *base_addr = periph_hw->sys_base;
+	u32 reg;
+
+	reg = readl_relaxed(base_addr + REG_SUBBLK_RESET_CR);
+	if ((reg & (1u << periph->shift)) == 0u) {
+		reg = readl_relaxed(base_addr + REG_SUBBLK_CLOCK_CR);
+		if (reg & (1u << periph->shift))
+			return 1;
+	}
+
+	return 0;
+}
+
+static unsigned long mpfs_periph_clk_recalc_rate(struct clk_hw *hw, unsigned long prate)
+{
+	return prate;
+}
+
+static const struct clk_ops mpfs_periph_clk_ops = {
+	.enable = mpfs_periph_clk_enable,
+	.disable = mpfs_periph_clk_disable,
+	.is_enabled = mpfs_periph_clk_is_enabled,
+	.recalc_rate = mpfs_periph_clk_recalc_rate,
+};
+
+#define CLK_PERIPH(_id, _name, _parent, _shift, _flags) {				\
+		.periph.id = _id,							\
+		.periph.name = _name,							\
+		.periph.shift = _shift,							\
+		.hw.init = CLK_HW_INIT_HW(_name, _parent, &mpfs_periph_clk_ops,	\
+					  _flags),					\
+	}
+
+#define PARENT_CLK(PARENT) (&mpfs_cfg_clks[CLK_##PARENT].hw)
+
+static struct mpfs_periph_hw_clock mpfs_periph_clks[] = {
+	CLK_PERIPH(CLK_ENVM, "clk_periph_envm", PARENT_CLK(AHB), 0, CLK_IS_CRITICAL),
+	CLK_PERIPH(CLK_MAC0, "clk_periph_mac0", PARENT_CLK(AHB), 1, 0),
+	CLK_PERIPH(CLK_MAC1, "clk_periph_mac1", PARENT_CLK(AHB), 2, 0),
+	CLK_PERIPH(CLK_MMC, "clk_periph_mmc", PARENT_CLK(AHB), 3, 0),
+	CLK_PERIPH(CLK_TIMER, "clk_periph_timer", PARENT_CLK(AHB), 4, 0),
+	CLK_PERIPH(CLK_MMUART0, "clk_periph_mmuart0", PARENT_CLK(AHB), 5, CLK_IS_CRITICAL),
+	CLK_PERIPH(CLK_MMUART1, "clk_periph_mmuart1", PARENT_CLK(AHB), 6, 0),
+	CLK_PERIPH(CLK_MMUART2, "clk_periph_mmuart2", PARENT_CLK(AHB), 7, 0),
+	CLK_PERIPH(CLK_MMUART3, "clk_periph_mmuart3", PARENT_CLK(AHB), 8, 0),
+	CLK_PERIPH(CLK_MMUART4, "clk_periph_mmuart4", PARENT_CLK(AHB), 9, 0),
+	CLK_PERIPH(CLK_SPI0, "clk_periph_spi0", PARENT_CLK(AHB), 10, 0),
+	CLK_PERIPH(CLK_SPI1, "clk_periph_spi1", PARENT_CLK(AHB), 11, 0),
+	CLK_PERIPH(CLK_I2C0, "clk_periph_i2c0", PARENT_CLK(AHB), 12, 0),
+	CLK_PERIPH(CLK_I2C1, "clk_periph_i2c1", PARENT_CLK(AHB), 13, 0),
+	CLK_PERIPH(CLK_CAN0, "clk_periph_can0", PARENT_CLK(AHB), 14, 0),
+	CLK_PERIPH(CLK_CAN1, "clk_periph_can1", PARENT_CLK(AHB), 15, 0),
+	CLK_PERIPH(CLK_USB, "clk_periph_usb", PARENT_CLK(AHB), 16, 0),
+	CLK_PERIPH(CLK_RTC, "clk_periph_rtc", PARENT_CLK(AHB), 18, 0),
+	CLK_PERIPH(CLK_QSPI, "clk_periph_qspi", PARENT_CLK(AHB), 19, 0),
+	CLK_PERIPH(CLK_GPIO0, "clk_periph_gpio0", PARENT_CLK(AHB), 20, 0),
+	CLK_PERIPH(CLK_GPIO1, "clk_periph_gpio1", PARENT_CLK(AHB), 21, 0),
+	CLK_PERIPH(CLK_GPIO2, "clk_periph_gpio2", PARENT_CLK(AHB), 22, 0),
+	CLK_PERIPH(CLK_DDRC, "clk_periph_ddrc", PARENT_CLK(AHB), 23, CLK_IS_CRITICAL),
+	CLK_PERIPH(CLK_FIC0, "clk_periph_fic0", PARENT_CLK(AHB), 24, 0),
+	CLK_PERIPH(CLK_FIC1, "clk_periph_fic1", PARENT_CLK(AHB), 25, 0),
+	CLK_PERIPH(CLK_FIC2, "clk_periph_fic2", PARENT_CLK(AHB), 26, 0),
+	CLK_PERIPH(CLK_FIC3, "clk_periph_fic3", PARENT_CLK(AHB), 27, 0),
+	CLK_PERIPH(CLK_ATHENA, "clk_periph_athena", PARENT_CLK(AHB), 28, 0),
+	CLK_PERIPH(CLK_CFM, "clk_periph_cfm", PARENT_CLK(AHB), 29, 0),
+};
+
+static void mpfs_clk_unregister_periph(struct device *dev, struct clk_hw *hw)
+{
+	struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
+
+	devm_clk_hw_unregister(dev, hw);
+	kfree(periph_hw);
+}
+
+static struct clk_hw *mpfs_clk_register_periph(struct device *dev,
+					       struct mpfs_periph_hw_clock *periph_hw,
+					       void __iomem *sys_base)
+{
+	struct clk_hw *hw;
+	int err;
+
+	periph_hw->sys_base = sys_base;
+	periph_hw->lock = &mpfs_clk_lock;
+
+	hw = &periph_hw->hw;
+	err = devm_clk_hw_register(dev, hw);
+	if (err)
+		return ERR_PTR(err);
+
+	return hw;
+}
+
+static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
+				     int num_clks, struct mpfs_clock_data *data)
+{
+	struct clk_hw *hw;
+	void __iomem *sys_base = data->base;
+	unsigned int i, id;
+
+	for (i = 0; i < num_clks; i++) {
+		struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
+
+		hw = mpfs_clk_register_periph(dev, periph_hw, sys_base);
+		if (IS_ERR(hw)) {
+			dev_err(dev, "%s: failed to register clock %s\n", __func__,
+				periph_hw->periph.name);
+			goto err_clk;
+		}
+
+		id = periph_hws[i].periph.id;
+		data->hw_data.hws[id] = hw;
+	}
+
+	return 0;
+
+err_clk:
+	while (i--)
+		mpfs_clk_unregister_periph(dev, data->hw_data.hws[periph_hws[i].periph.id]);
+
+	return PTR_ERR(hw);
+}
+
+static int mpfs_clk_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mpfs_clock_data *clk_data;
+	struct resource *res;
+	int num_clks;
+	int ret;
+
+	num_clks = ARRAY_SIZE(mpfs_cfg_clks) + ARRAY_SIZE(mpfs_periph_clks);
+
+	clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
+	if (!clk_data)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	clk_data->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(clk_data->base))
+		return PTR_ERR(clk_data->base);
+
+	clk_data->hw_data.num = num_clks;
+
+	ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
+	if (ret)
+		goto err_clk;
+
+	ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
+					clk_data);
+	if (ret)
+		goto err_clk;
+
+	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
+	if (ret)
+		goto err_clk;
+
+	dev_info(dev, "registered MPFS core clocks\n");
+	return ret;
+
+err_clk:
+	dev_err(dev, "failed to register MPFS core clocks\n");
+	return ret;
+}
+
+static const struct of_device_id mpfs_clk_of_match_table[] = {
+	{ .compatible = "microchip,mpfs-clkcfg", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, mpfs_clk_match_table);
+
+static struct platform_driver mpfs_clk_driver = {
+	.probe = mpfs_clk_probe,
+	.driver	= {
+		.name = "microchip-mpfs-clkcfg",
+		.of_match_table = mpfs_clk_of_match_table,
+	},
+};
+
+static int __init clk_mpfs_init(void)
+{
+	return platform_driver_register(&mpfs_clk_driver);
+}
+core_initcall(clk_mpfs_init);
+
+static void __exit clk_mpfs_exit(void)
+{
+	platform_driver_unregister(&mpfs_clk_driver);
+}
+module_exit(clk_mpfs_exit);
+
+MODULE_DESCRIPTION("Microchip PolarFire SoC Clock Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:clk-mpfs");
-- 
2.33.1

Re: [PATCH v6 2/2] clk: microchip: Add driver for Microchip PolarFire SoC

[Geert Uytterhoeven]

Hi Conor, Daire,

On Tue, Nov 30, 2021 at 3:06 PM <conor.dooley@microchip.com> wrote:
> From: Daire McNamara <daire.mcnamara@microchip.com>
>
> Add support for clock configuration on Microchip PolarFire SoC
>
> Signed-off-by: Daire McNamara <daire.mcnamara@microchip.com>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

Thanks for your patch!

> --- /dev/null
> +++ b/drivers/clk/microchip/clk-mpfs.c
> @@ -0,0 +1,444 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Daire McNamara,<daire.mcnamara@microchip.com>
> + * Copyright (C) 2020 Microchip Technology Inc.  All rights reserved.
> + */
> +#include <linux/clk-provider.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <dt-bindings/clock/microchip,mpfs-clock.h>
> +
> +/* address offset of control registers */
> +#define REG_CLOCK_CONFIG_CR    0x08u
> +#define REG_SUBBLK_CLOCK_CR    0x84u
> +#define REG_SUBBLK_RESET_CR    0x88u
> +
> +struct mpfs_clock_data {
> +       void __iomem *base;
> +       struct clk_hw_onecell_data hw_data;
> +};
> +
> +struct mpfs_cfg_clock {
> +       unsigned int id;

implicit gap of 4 bytes

> +       const char *name;
> +       u8 shift;
> +       u8 width;

implicit gap of 6 bytes

> +       const struct clk_div_table *table;
> +       unsigned long flags;

Hence you better move id, shift, and width to the end.

> +};
> +
> +struct mpfs_cfg_hw_clock {
> +       struct mpfs_cfg_clock cfg;
> +       void __iomem *sys_base;
> +       /* lock is used to prevent multiple writes */
> +       spinlock_t *lock;
> +       struct clk_hw hw;
> +       struct clk_init_data init;
> +};
> +
> +#define to_mpfs_cfg_clk(_hw) container_of(_hw, struct mpfs_cfg_hw_clock, hw)
> +
> +struct mpfs_periph_clock {
> +       unsigned int id;

implicit gap of 4 bytes

> +       const char *name;
> +       u8 shift;

implicit gap of 7 bytes

> +       unsigned long flags;
> +};
> +
> +struct mpfs_periph_hw_clock {
> +       struct mpfs_periph_clock periph;
> +       void __iomem *sys_base;
> +       /* lock is used to prevent multiple writes */
> +       spinlock_t *lock;

This is not used?

> +       struct clk_hw hw;
> +};
> +
> +#define to_mpfs_periph_clk(_hw) container_of(_hw, struct mpfs_periph_hw_clock, hw)
> +
> +/*
> + * mpfs_clk_lock prevents anything else from writing to the
> + * mpfs clk block while a software locked register is being written.
> + */
> +static DEFINE_SPINLOCK(mpfs_clk_lock);
> +
> +static struct clk_parent_data mpfs_cfg_parent[] = {
> +       { .fw_name = "msspllclk", .name = "msspllclk" },

So you rely on the name of the fixed-clock reference clock? That is
very fragile. Please instead use devm_clk_get() to get the reference
clock from the "clocks" property of the clock-controller node.

> +static unsigned long mpfs_cfg_clk_recalc_rate(struct clk_hw *hw, unsigned long prate)
> +{
> +       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
> +       struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
> +       void __iomem *base_addr = cfg_hw->sys_base;
> +       unsigned long rate;
> +       u32 val;
> +
> +       val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR) >> cfg->shift;
> +       val &= clk_div_mask(cfg->width);
> +       rate = prate / (1u << val);
> +
> +       return rate;

return prate / (1u << val);

> +}

> +static int mpfs_cfg_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
> +{
> +       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
> +       struct mpfs_cfg_clock *cfg = &cfg_hw->cfg;
> +       void __iomem *base_addr = cfg_hw->sys_base;
> +       unsigned long flags = 0;
> +       u32 val;
> +       int divider_setting;
> +
> +       divider_setting = divider_get_val(rate, prate, cfg->table, cfg->width, cfg_hw->cfg.flags);
> +
> +       if (divider_setting < 0)
> +               return divider_setting;
> +
> +       if (cfg_hw->lock)

Isn't this branch always taken?

> +               spin_lock_irqsave(cfg_hw->lock, flags);
> +       else
> +               __acquire(cfg_hw->lock);
> +
> +       val = readl_relaxed(base_addr + REG_CLOCK_CONFIG_CR);
> +       val &= ~(clk_div_mask(cfg->width) << cfg_hw->cfg.shift);
> +       val |= divider_setting << cfg->shift;
> +       writel_relaxed(val, base_addr + REG_CLOCK_CONFIG_CR);
> +
> +       if (cfg_hw->lock)
> +               spin_unlock_irqrestore(cfg_hw->lock, flags);
> +       else
> +               __release(cfg_hw->lock);
> +
> +       return 0;
> +}

> +static void mpfs_clk_unregister_cfg(struct device *dev, struct clk_hw *hw)
> +{
> +       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
> +
> +       devm_clk_hw_unregister(dev, hw);
> +       kfree(cfg_hw);

This is freeing a part of the big array allocated with devm_kzalloc()?

> +}
> +
> +static struct clk_hw *mpfs_clk_register_cfg(struct device *dev,
> +                                           struct mpfs_cfg_hw_clock *cfg_hw,
> +                                           void __iomem *sys_base)
> +{
> +       struct clk_hw *hw;
> +       int err;
> +
> +       cfg_hw->sys_base = sys_base;
> +       cfg_hw->lock = &mpfs_clk_lock;
> +
> +       hw = &cfg_hw->hw;
> +       err = devm_clk_hw_register(dev, hw);
> +       if (err)
> +               return ERR_PTR(err);
> +
> +       return hw;
> +}
> +
> +static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
> +                                 int num_clks, struct mpfs_clock_data *data)

unsigned int num_clks

> +{
> +       struct clk_hw *hw;
> +       void __iomem *sys_base = data->base;
> +       unsigned int i, id;
> +
> +       for (i = 0; i < num_clks; i++) {
> +               struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
> +
> +               hw = mpfs_clk_register_cfg(dev, cfg_hw, sys_base);
> +               if (IS_ERR(hw)) {
> +                       dev_err(dev, "%s: failed to register clock %s\n", __func__,

I guess the __func__ can be dropped, as the clock name is unique?

> +                               cfg_hw->cfg.name);
> +                       goto err_clk;
> +               }
> +
> +               id = cfg_hws[i].cfg.id;
> +               data->hw_data.hws[id] = hw;
> +       }
> +
> +       return 0;
> +
> +err_clk:
> +       while (i--)
> +               mpfs_clk_unregister_cfg(dev, data->hw_data.hws[cfg_hws[i].cfg.id]);
> +
> +       return PTR_ERR(hw);
> +}

> +static void mpfs_clk_unregister_periph(struct device *dev, struct clk_hw *hw)
> +{
> +       struct mpfs_periph_hw_clock *periph_hw = to_mpfs_periph_clk(hw);
> +
> +       devm_clk_hw_unregister(dev, hw);
> +       kfree(periph_hw);'

This is freeing a part of the big array allocated with devm_kzalloc()?

> +}

> +static int mpfs_clk_register_periphs(struct device *dev, struct mpfs_periph_hw_clock *periph_hws,
> +                                    int num_clks, struct mpfs_clock_data *data)
> +{
> +       struct clk_hw *hw;
> +       void __iomem *sys_base = data->base;
> +       unsigned int i, id;
> +
> +       for (i = 0; i < num_clks; i++) {
> +               struct mpfs_periph_hw_clock *periph_hw = &periph_hws[i];
> +
> +               hw = mpfs_clk_register_periph(dev, periph_hw, sys_base);
> +               if (IS_ERR(hw)) {
> +                       dev_err(dev, "%s: failed to register clock %s\n", __func__,

I guess the __func__ can be dropped, as the clock name is unique?


> +                               periph_hw->periph.name);
> +                       goto err_clk;
> +               }
> +
> +               id = periph_hws[i].periph.id;
> +               data->hw_data.hws[id] = hw;
> +       }
> +
> +       return 0;
> +
> +err_clk:
> +       while (i--)
> +               mpfs_clk_unregister_periph(dev, data->hw_data.hws[periph_hws[i].periph.id]);
> +
> +       return PTR_ERR(hw);
> +}
> +
> +static int mpfs_clk_probe(struct platform_device *pdev)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct mpfs_clock_data *clk_data;
> +       struct resource *res;
> +       int num_clks;

unsigned int

> +       int ret;
> +
> +       num_clks = ARRAY_SIZE(mpfs_cfg_clks) + ARRAY_SIZE(mpfs_periph_clks);

As mpfs_periph_clks[] lacks an entry for CLK_RESERVED, num_clks is
one too small...

> +
> +       clk_data = devm_kzalloc(dev, struct_size(clk_data, hw_data.hws, num_clks), GFP_KERNEL);
> +       if (!clk_data)
> +               return -ENOMEM;
> +
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       clk_data->base = devm_ioremap_resource(dev, res);
> +       if (IS_ERR(clk_data->base))
> +               return PTR_ERR(clk_data->base);
> +
> +       clk_data->hw_data.num = num_clks;
> +
> +       ret = mpfs_clk_register_cfgs(dev, mpfs_cfg_clks, ARRAY_SIZE(mpfs_cfg_clks), clk_data);
> +       if (ret)
> +               goto err_clk;
> +
> +       ret = mpfs_clk_register_periphs(dev, mpfs_periph_clks, ARRAY_SIZE(mpfs_periph_clks),
> +                                       clk_data);

... and initializing CLK_CFM will write beyond the end of clk_data[].

> +       if (ret)
> +               goto err_clk;
> +
> +       ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, &clk_data->hw_data);
> +       if (ret)
> +               goto err_clk;
> +
> +       dev_info(dev, "registered MPFS core clocks\n");
> +       return ret;
> +
> +err_clk:
> +       dev_err(dev, "failed to register MPFS core clocks\n");
> +       return ret;
> +}

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v6 2/2] clk: microchip: Add driver for Microchip PolarFire SoC

[Conor.Dooley]

Hi Geert,
Just going to ack the other items you raised for now, but curious about 
this one:
On 06/12/2021 15:53, Geert Uytterhoeven wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>> +static void mpfs_clk_unregister_cfg(struct device *dev, struct clk_hw *hw)
>> +{
>> +       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
>> +
>> +       devm_clk_hw_unregister(dev, hw);
>> +       kfree(cfg_hw);
> 
> This is freeing a part of the big array allocated with devm_kzalloc()?
I took a look at this, and I don't think it is freeing the devm 
allocated array.

To me, what is actually being freed is an element in the array of 
structs passed to mpfs_clk_register_cfgs in the probe function.
However, this struct is statically defined - so its elements shouldn't 
be freed at all?

drivers/clk/clk-bm1880.c has the same behaviour in the unregister 
function, where it calls kfree on the elements of a static array of clk 
structs. So if my understanding is correct it would need fixing there too.

Cheers,
Conor.
>> +}
>> +
>> +static struct clk_hw *mpfs_clk_register_cfg(struct device *dev,
>> +                                           struct mpfs_cfg_hw_clock *cfg_hw,
>> +                                           void __iomem *sys_base)
>> +{
>> +       struct clk_hw *hw;
>> +       int err;
>> +
>> +       cfg_hw->sys_base = sys_base;
>> +       cfg_hw->lock = &mpfs_clk_lock;
>> +
>> +       hw = &cfg_hw->hw;
>> +       err = devm_clk_hw_register(dev, hw);
>> +       if (err)
>> +               return ERR_PTR(err);
>> +
>> +       return hw;
>> +}
>> +
>> +static int mpfs_clk_register_cfgs(struct device *dev, struct mpfs_cfg_hw_clock *cfg_hws,
>> +                                 int num_clks, struct mpfs_clock_data *data)
> 
> unsigned int num_clks
> 
>> +{
>> +       struct clk_hw *hw;
>> +       void __iomem *sys_base = data->base;
>> +       unsigned int i, id;
>> +
>> +       for (i = 0; i < num_clks; i++) {
>> +               struct mpfs_cfg_hw_clock *cfg_hw = &cfg_hws[i];
>> +
>> +               hw = mpfs_clk_register_cfg(dev, cfg_hw, sys_base);
>> +               if (IS_ERR(hw)) {
>> +                       dev_err(dev, "%s: failed to register clock %s\n", __func__,
> 
> I guess the __func__ can be dropped, as the clock name is unique?
> 
>> +                               cfg_hw->cfg.name);
>> +                       goto err_clk;
>> +               }
>> +
>> +               id = cfg_hws[i].cfg.id;
>> +               data->hw_data.hws[id] = hw;
>> +       }
>> +
>> +       return 0;
>> +
>> +err_clk:
>> +       while (i--)
>> +               mpfs_clk_unregister_cfg(dev, data->hw_data.hws[cfg_hws[i].cfg.id]);
>> +
>> +       return PTR_ERR(hw);
>> +}

Re: [PATCH v6 2/2] clk: microchip: Add driver for Microchip PolarFire SoC

[Geert Uytterhoeven]

Hi Conor,

On Wed, Dec 8, 2021 at 4:30 PM <Conor.Dooley@microchip.com> wrote:
> Just going to ack the other items you raised for now, but curious about
> this one:
> On 06/12/2021 15:53, Geert Uytterhoeven wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >> +static void mpfs_clk_unregister_cfg(struct device *dev, struct clk_hw *hw)
> >> +{
> >> +       struct mpfs_cfg_hw_clock *cfg_hw = to_mpfs_cfg_clk(hw);
> >> +
> >> +       devm_clk_hw_unregister(dev, hw);
> >> +       kfree(cfg_hw);
> >
> > This is freeing a part of the big array allocated with devm_kzalloc()?
> I took a look at this, and I don't think it is freeing the devm
> allocated array.
>
> To me, what is actually being freed is an element in the array of
> structs passed to mpfs_clk_register_cfgs in the probe function.
> However, this struct is statically defined - so its elements shouldn't
> be freed at all?

You're right, it's part of the static array.  I was misled by the
back-and-forth conversions between the different types.
Regardless, the kfree() calls should be removed.

> drivers/clk/clk-bm1880.c has the same behaviour in the unregister
> function, where it calls kfree on the elements of a static array of clk
> structs. So if my understanding is correct it would need fixing there too.

If that is true (didn't check), it needs to be fixed, too.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds