[PATCH v4 10/14] clk: imx: Add generic blk-ctl driver

[Abel Vesa]

The i.MX8MP platform introduces a new type of IP which is called BLK_CTL in
RM and usually is comprised of some GPRs that are considered too
generic to be part of any dedicated IP from that specific subsystem.

In general, some of the GPRs have some clock bits, some have reset bits,
so in order to be able to use the imx clock API, this needs to be
in a clock driver. From there it can use the reset controller API and
leave the rest to the syscon.

Signed-off-by: Abel Vesa <abel.vesa@xxxxxxx>
---
 drivers/clk/imx/Makefile      |   2 +-
 drivers/clk/imx/clk-blk-ctl.c | 302 ++++++++++++++++++++++++++++++++++++++++++
 drivers/clk/imx/clk-blk-ctl.h |  80 +++++++++++
 3 files changed, 383 insertions(+), 1 deletion(-)
 create mode 100644 drivers/clk/imx/clk-blk-ctl.c
 create mode 100644 drivers/clk/imx/clk-blk-ctl.h

diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile
index dd6a737..3d6d9cb 100644
--- a/drivers/clk/imx/Makefile
+++ b/drivers/clk/imx/Makefile
@@ -23,7 +23,7 @@ obj-$(CONFIG_MXC_CLK) += mxc-clk.o
 
 obj-$(CONFIG_CLK_IMX8MM) += clk-imx8mm.o
 obj-$(CONFIG_CLK_IMX8MN) += clk-imx8mn.o
-obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o
+obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o clk-blk-ctl.o
 obj-$(CONFIG_CLK_IMX8MQ) += clk-imx8mq.o
 
 obj-$(CONFIG_MXC_CLK_SCU) += clk-imx-scu.o clk-imx-lpcg-scu.o
diff --git a/drivers/clk/imx/clk-blk-ctl.c b/drivers/clk/imx/clk-blk-ctl.c
new file mode 100644
index 00000000..9ac0ed0
--- /dev/null
+++ b/drivers/clk/imx/clk-blk-ctl.c
@@ -0,0 +1,302 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 NXP.
+ */
+
+#include <linux/clk.h>
+#include <linux/reset-controller.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include "clk.h"
+#include "clk-blk-ctl.h"
+
+struct imx_reset_hw {
+	u32 offset;
+	u32 shift;
+	u32 mask;
+	unsigned long asserted;
+};
+
+struct imx_pm_safekeep_info {
+	uint32_t *regs_values;
+	uint32_t *regs_offsets;
+	uint32_t regs_num;
+};
+
+struct imx_blk_ctl_drvdata {
+	void __iomem *base;
+	struct reset_controller_dev rcdev;
+	struct imx_reset_hw *rst_hws;
+	struct imx_pm_safekeep_info pm_info;
+
+	spinlock_t lock;
+};
+
+static void __maybe_unused imx_blk_ctl_read_write(struct device *dev,
+							bool write)
+{
+	struct imx_blk_ctl_drvdata *drvdata = dev_get_drvdata(dev);
+	struct imx_pm_safekeep_info *pm_info = &drvdata->pm_info;
+	void __iomem *base = drvdata->base;
+	int i;
+
+	if (!pm_info->regs_num)
+		return;
+
+	for (i = 0; i < pm_info->regs_num; i++) {
+		u32 offset = pm_info->regs_offsets[i];
+
+		if (write)
+			writel(pm_info->regs_values[i], base + offset);
+		else
+			pm_info->regs_values[i] = readl(base + offset);
+	}
+
+}
+
+static int __maybe_unused imx_blk_ctl_runtime_suspend(struct device *dev)
+{
+	imx_blk_ctl_read_write(dev, false);
+
+	return 0;
+}
+
+static int __maybe_unused imx_blk_ctl_runtime_resume(struct device *dev)
+{
+	imx_blk_ctl_read_write(dev, true);
+
+	return 0;
+}
+
+const struct dev_pm_ops imx_blk_ctl_pm_ops = {
+	SET_RUNTIME_PM_OPS(imx_blk_ctl_runtime_suspend,
+			   imx_blk_ctl_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+			   pm_runtime_force_resume)
+};
+EXPORT_SYMBOL_GPL(imx_blk_ctl_pm_ops);
+
+static int imx_blk_ctl_reset_set(struct reset_controller_dev *rcdev,
+				  unsigned long id, bool assert)
+{
+	struct imx_blk_ctl_drvdata *drvdata = container_of(rcdev,
+			struct imx_blk_ctl_drvdata, rcdev);
+	unsigned int offset = drvdata->rst_hws[id].offset;
+	unsigned int shift = drvdata->rst_hws[id].shift;
+	unsigned int mask = drvdata->rst_hws[id].mask;
+	void __iomem *reg_addr = drvdata->base + offset;
+	unsigned long flags;
+	u32 reg;
+
+	if (!assert && !test_bit(1, &drvdata->rst_hws[id].asserted))
+		return -ENODEV;
+
+	if (assert && !test_and_set_bit(1, &drvdata->rst_hws[id].asserted))
+		pm_runtime_get_sync(rcdev->dev);
+
+	spin_lock_irqsave(&drvdata->lock, flags);
+
+	reg = readl(reg_addr);
+	if (assert)
+		writel(reg & ~(mask << shift), reg_addr);
+	else
+		writel(reg | (mask << shift), reg_addr);
+
+	spin_unlock_irqrestore(&drvdata->lock, flags);
+
+	if (!assert && test_and_clear_bit(1, &drvdata->rst_hws[id].asserted))
+		pm_runtime_put(rcdev->dev);
+
+	return 0;
+}
+
+static int imx_blk_ctl_reset_assert(struct reset_controller_dev *rcdev,
+					   unsigned long id)
+{
+	return imx_blk_ctl_reset_set(rcdev, id, true);
+}
+
+static int imx_blk_ctl_reset_deassert(struct reset_controller_dev *rcdev,
+					     unsigned long id)
+{
+	return imx_blk_ctl_reset_set(rcdev, id, false);
+}
+
+static const struct reset_control_ops imx_blk_ctl_reset_ops = {
+	.assert		= imx_blk_ctl_reset_assert,
+	.deassert	= imx_blk_ctl_reset_deassert,
+};
+
+static int imx_blk_ctl_register_reset_controller(struct device *dev)
+{
+	const struct imx_blk_ctl_dev_data *dev_data = of_device_get_match_data(dev);
+	struct imx_blk_ctl_drvdata *drvdata = dev_get_drvdata(dev);
+	int max = dev_data->resets_max;
+	struct imx_reset_hw *hws;
+	int i;
+
+	spin_lock_init(&drvdata->lock);
+
+	drvdata->rcdev.owner     = THIS_MODULE;
+	drvdata->rcdev.nr_resets = max;
+	drvdata->rcdev.ops       = &imx_blk_ctl_reset_ops;
+	drvdata->rcdev.of_node   = dev->of_node;
+	drvdata->rcdev.dev	 = dev;
+
+	drvdata->rst_hws = devm_kcalloc(dev, max, sizeof(struct imx_reset_hw),
+					GFP_KERNEL);
+	hws = drvdata->rst_hws;
+
+	for (i = 0; i < dev_data->hws_num; i++) {
+		struct imx_blk_ctl_hw *hw = &dev_data->hws[i];
+
+		if (hw->type != BLK_CTL_RESET)
+			continue;
+
+		hws[hw->id].offset = hw->offset;
+		hws[hw->id].shift = hw->shift;
+		hws[hw->id].mask = hw->mask;
+	}
+
+	return devm_reset_controller_register(dev, &drvdata->rcdev);
+}
+static struct clk_hw *imx_blk_ctl_register_one_clock(struct device *dev,
+						struct imx_blk_ctl_hw *hw)
+{
+	struct imx_blk_ctl_drvdata *drvdata = dev_get_drvdata(dev);
+	void __iomem *base = drvdata->base;
+	struct clk_hw *clk_hw = NULL;
+
+	switch (hw->type) {
+	case BLK_CTL_CLK_MUX:
+		clk_hw = imx_dev_clk_hw_mux_flags(dev, hw->name,
+						  base + hw->offset,
+						  hw->shift, hw->width,
+						  hw->parents,
+						  hw->parents_count,
+						  hw->flags);
+		break;
+	case BLK_CTL_CLK_GATE:
+		clk_hw = imx_dev_clk_hw_gate(dev, hw->name, hw->parents,
+					     base + hw->offset, hw->shift);
+		break;
+	case BLK_CTL_CLK_SHARED_GATE:
+		clk_hw = imx_dev_clk_hw_gate_shared(dev, hw->name,
+						    hw->parents,
+						    base + hw->offset,
+						    hw->shift,
+						    hw->shared_count);
+		break;
+	case BLK_CTL_CLK_PLL14XX:
+		clk_hw = imx_dev_clk_hw_pll14xx(dev, hw->name, hw->parents,
+						base + hw->offset, hw->pll_tbl);
+		break;
+	};
+
+	return clk_hw;
+}
+
+static int imx_blk_ctl_register_clock_controller(struct device *dev)
+{
+	const struct imx_blk_ctl_dev_data *dev_data = of_device_get_match_data(dev);
+	struct clk_hw_onecell_data *clk_hw_data;
+	struct clk_hw **hws;
+	int i;
+
+	clk_hw_data = devm_kzalloc(dev, struct_size(clk_hw_data, hws,
+				dev_data->hws_num), GFP_KERNEL);
+	if (WARN_ON(!clk_hw_data))
+		return -ENOMEM;
+
+	clk_hw_data->num = dev_data->clocks_max;
+	hws = clk_hw_data->hws;
+
+	for (i = 0; i < dev_data->hws_num; i++) {
+		struct imx_blk_ctl_hw *hw = &dev_data->hws[i];
+
+		if (hw->type == BLK_CTL_RESET)
+			continue;
+
+		hws[hw->id] = imx_blk_ctl_register_one_clock(dev, hw);
+	}
+
+	imx_check_clk_hws(hws, dev_data->clocks_max);
+
+	return of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
+					clk_hw_data);
+}
+
+static int imx_blk_ctl_init_runtime_pm_safekeeping(struct device *dev)
+{
+	const struct imx_blk_ctl_dev_data *dev_data = of_device_get_match_data(dev);
+	struct imx_blk_ctl_drvdata *drvdata = dev_get_drvdata(dev);
+	struct imx_pm_safekeep_info *pm_info = &drvdata->pm_info;
+	u32 regs_num = dev_data->pm_runtime_saved_regs_num;
+	const u32 *regs_offsets = dev_data->pm_runtime_saved_regs;
+
+	if (!dev_data->pm_runtime_saved_regs_num)
+		return 0;
+
+	pm_info->regs_values = devm_kzalloc(dev,
+					    sizeof(u32) * regs_num,
+					    GFP_KERNEL);
+	if (WARN_ON(IS_ERR(pm_info->regs_values)))
+		return PTR_ERR(pm_info->regs_values);
+
+	pm_info->regs_offsets = kmemdup(regs_offsets,
+					regs_num * sizeof(u32), GFP_KERNEL);
+	if (WARN_ON(IS_ERR(pm_info->regs_offsets)))
+		return PTR_ERR(pm_info->regs_offsets);
+
+	pm_info->regs_num = regs_num;
+
+	return 0;
+}
+
+int imx_blk_ctl_register(struct platform_device *pdev)
+{
+	struct imx_blk_ctl_drvdata *drvdata;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+	if (WARN_ON(!drvdata))
+		return -ENOMEM;
+
+	drvdata->base = devm_platform_ioremap_resource(pdev, 0);
+	if (WARN_ON(IS_ERR(drvdata->base)))
+		return PTR_ERR(drvdata->base);
+
+	dev_set_drvdata(dev, drvdata);
+
+	ret = imx_blk_ctl_init_runtime_pm_safekeeping(dev);
+	if (ret)
+		return ret;
+
+	pm_runtime_get_noresume(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	ret = imx_blk_ctl_register_clock_controller(dev);
+	if (ret) {
+		pm_runtime_put(dev);
+		return ret;
+	}
+
+	ret = imx_blk_ctl_register_reset_controller(dev);
+
+	pm_runtime_put(dev);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(imx_blk_ctl_register);
diff --git a/drivers/clk/imx/clk-blk-ctl.h b/drivers/clk/imx/clk-blk-ctl.h
new file mode 100644
index 00000000..3f14a47
--- /dev/null
+++ b/drivers/clk/imx/clk-blk-ctl.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __MACH_IMX_CLK_BLK_CTL_H
+#define __MACH_IMX_CLK_BLK_CTL_H
+
+enum imx_blk_ctl_hw_type {
+	BLK_CTL_CLK_MUX,
+	BLK_CTL_CLK_GATE,
+	BLK_CTL_CLK_SHARED_GATE,
+	BLK_CTL_CLK_PLL14XX,
+	BLK_CTL_RESET,
+};
+
+struct imx_blk_ctl_hw {
+	int type;
+	char *name;
+	u32 offset;
+	u32 shift;
+	u32 mask;
+	u32 width;
+	u32 flags;
+	u32 id;
+	const void *parents;
+	u32 parents_count;
+	int *shared_count;
+	const struct imx_pll14xx_clk *pll_tbl;
+};
+
+struct imx_blk_ctl_dev_data {
+	struct imx_blk_ctl_hw *hws;
+	u32 hws_num;
+
+	u32 clocks_max;
+	u32 resets_max;
+
+	u32 pm_runtime_saved_regs_num;
+	u32 pm_runtime_saved_regs[];
+};
+
+#define IMX_BLK_CTL(_type, _name, _id, _offset, _shift, _width, _mask, _parents, _parents_count, _flags, sh_count, _pll_tbl) \
+	{						\
+		.type = _type,				\
+		.name = _name,				\
+		.id = _id,				\
+		.offset = _offset,			\
+		.shift = _shift,			\
+		.width = _width,			\
+		.mask = _mask,				\
+		.parents = _parents,			\
+		.parents_count = _parents_count,	\
+		.flags = _flags,			\
+		.shared_count = sh_count,		\
+		.pll_tbl = _pll_tbl,			\
+	}
+
+#define IMX_BLK_CTL_CLK_MUX(_name, _id, _offset, _shift, _width, _parents) \
+	IMX_BLK_CTL(BLK_CTL_CLK_MUX, _name, _id, _offset, _shift, _width, 0, _parents, ARRAY_SIZE(_parents), 0, NULL, NULL)
+
+#define IMX_BLK_CTL_CLK_MUX_FLAGS(_name, _id, _offset, _shift, _width, _parents, _flags) \
+	IMX_BLK_CTL(BLK_CTL_CLK_MUX, _name, _id, _offset, _shift, _width, 0, _parents, ARRAY_SIZE(_parents), _flags, NULL, NULL)
+
+#define IMX_BLK_CTL_CLK_GATE(_name, _id, _offset, _shift, _parents) \
+	IMX_BLK_CTL(BLK_CTL_CLK_GATE, _name, _id, _offset, _shift, 1, 0, _parents, 1, 0, NULL, NULL)
+
+#define IMX_BLK_CTL_CLK_SHARED_GATE(_name, _id, _offset, _shift, _parents, sh_count) \
+	IMX_BLK_CTL(BLK_CTL_CLK_SHARED_GATE, _name, _id, _offset, _shift, 1, 0, _parents, 1, 0, sh_count, NULL)
+
+#define IMX_BLK_CTL_CLK_PLL14XX(_name, _id, _offset, _parents, _pll_tbl) \
+	IMX_BLK_CTL(BLK_CTL_CLK_PLL14XX, _name, _id, _offset, 0, 0, 0, _parents, 1, 0, NULL, _pll_tbl)
+
+#define IMX_BLK_CTL_RESET(_id, _offset, _shift) \
+	IMX_BLK_CTL(BLK_CTL_RESET, NULL, _id, _offset, _shift, 0, 1, NULL, 0, 0, NULL, NULL)
+
+#define IMX_BLK_CTL_RESET_MASK(_id, _offset, _shift, mask) \
+	IMX_BLK_CTL(BLK_CTL_RESET, NULL, _id, _offset, _shift, 0, mask, NULL, 0, 0, NULL, NULL)
+
+extern const struct dev_pm_ops imx_blk_ctl_pm_ops;
+
+int imx_blk_ctl_register(struct platform_device *pdev);
+
+#endif
-- 
2.7.4