[PATCH v1 1/3] Coresight: Add driver to support for CSR

[Mao Jinlong <quic_jinlmao@quicinc.com>]

This driver provides support for CoreSight Slave Register block
that hosts miscellaneous configuration registers. Those
configuration registers can be used to control, various coresight
configurations.

Signed-off-by: Hao Zhang <quic_hazha@quicinc.com>
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
---
 drivers/hwtracing/coresight/Kconfig         |  12 ++
 drivers/hwtracing/coresight/Makefile        |   1 +
 drivers/hwtracing/coresight/coresight-csr.c | 142 ++++++++++++++++++++
 drivers/hwtracing/coresight/coresight-csr.h |  54 ++++++++
 4 files changed, 209 insertions(+)
 create mode 100644 drivers/hwtracing/coresight/coresight-csr.c
 create mode 100644 drivers/hwtracing/coresight/coresight-csr.h

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 2b5bbfffbc4f..e769ea3709d9 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -236,4 +236,16 @@ config CORESIGHT_TPDA
 
 	  To compile this driver as a module, choose M here: the module will be
 	  called coresight-tpda.
+
+config CORESIGHT_CSR
+	tristate "CoreSight Slave Register driver"
+	help
+	  This driver provides support for CoreSight Slave Register block
+	  that hosts miscellaneous configuration registers.
+	  Those configuration registers can be used to control, various
+	  coresight configurations.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called coresight-csr.
+
 endif
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 33bcc3f7b8ae..956c642d05f6 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -30,3 +30,4 @@ obj-$(CONFIG_CORESIGHT_TPDA) += coresight-tpda.o
 coresight-cti-y := coresight-cti-core.o	coresight-cti-platform.o \
 		   coresight-cti-sysfs.o
 obj-$(CONFIG_ULTRASOC_SMB) += ultrasoc-smb.o
+obj-$(CONFIG_CORESIGHT_CSR) += coresight-csr.o
diff --git a/drivers/hwtracing/coresight/coresight-csr.c b/drivers/hwtracing/coresight/coresight-csr.c
new file mode 100644
index 000000000000..a1403e8531ee
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-csr.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#include "coresight-priv.h"
+#include "coresight-csr.h"
+
+DEFINE_CORESIGHT_DEVLIST(csr_devs, "csr");
+
+static LIST_HEAD(csr_list);
+
+/*
+ * Get the CSR by name.
+ */
+struct coresight_csr *coresight_csr_get(const char *name)
+{
+	struct coresight_csr *csr;
+
+	list_for_each_entry(csr, &csr_list, link) {
+		if (!strcmp(csr->name, name))
+			return csr;
+	}
+	return ERR_PTR(-EINVAL);
+}
+EXPORT_SYMBOL(coresight_csr_get);
+
+/*
+ * Get the device node's name from device tree.
+ */
+int of_get_coresight_csr_name(struct device_node *node, const char **csr_name)
+{
+	struct device_node *csr_node;
+
+	csr_node = of_parse_phandle(node, "coresight-csr", 0);
+	if (!csr_node)
+		return -EINVAL;
+
+	*csr_name = csr_node->full_name;
+	of_node_put(csr_node);
+	return 0;
+}
+EXPORT_SYMBOL(of_get_coresight_csr_name);
+
+static int csr_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct coresight_platform_data *pdata;
+	struct csr_drvdata *drvdata;
+	struct resource *res;
+	struct coresight_desc desc = { 0 };
+
+	desc.name = coresight_alloc_device_name(&csr_devs, dev);
+	if (!desc.name)
+		return -ENOMEM;
+	pdata = coresight_get_platform_data(dev);
+	if (IS_ERR(pdata))
+		return PTR_ERR(pdata);
+	pdev->dev.platform_data = pdata;
+
+	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata)
+		return -ENOMEM;
+	drvdata->dev = &pdev->dev;
+	platform_set_drvdata(pdev, drvdata);
+
+	drvdata->clk = devm_clk_get(dev, "apb_pclk");
+	if (IS_ERR(drvdata->clk))
+		dev_dbg(dev, "csr not config clk\n");
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr-base");
+	if (!res)
+		return -ENODEV;
+	drvdata->pbase = res->start;
+
+	drvdata->base = devm_ioremap(dev, res->start, resource_size(res));
+	if (!drvdata->base)
+		return -ENOMEM;
+
+	desc.type = CORESIGHT_DEV_TYPE_HELPER;
+	desc.pdata = pdev->dev.platform_data;
+	desc.dev = &pdev->dev;
+
+	drvdata->csdev = coresight_register(&desc);
+	if (IS_ERR(drvdata->csdev))
+		return PTR_ERR(drvdata->csdev);
+
+	spin_lock_init(&drvdata->spin_lock);
+	drvdata->csr.name = pdev->dev.of_node->full_name;
+
+	list_add_tail(&drvdata->csr.link, &csr_list);
+
+	dev_dbg(dev, "CSR initialized: %s\n", drvdata->csr.name);
+	return 0;
+}
+
+static int csr_remove(struct platform_device *pdev)
+{
+	struct csr_drvdata *drvdata = platform_get_drvdata(pdev);
+
+	list_del(&drvdata->csr.link);
+	coresight_unregister(drvdata->csdev);
+	return 0;
+}
+
+static const struct of_device_id csr_match[] = {
+	{.compatible = "qcom,coresight-csr"},
+	{}
+};
+
+static struct platform_driver csr_driver = {
+	.probe          = csr_probe,
+	.remove         = csr_remove,
+	.driver         = {
+		.name   = "coresight-csr",
+		.of_match_table = csr_match,
+		.suppress_bind_attrs = true,
+	},
+};
+
+static int __init csr_init(void)
+{
+	return platform_driver_register(&csr_driver);
+}
+module_init(csr_init);
+
+static void __exit csr_exit(void)
+{
+	platform_driver_unregister(&csr_driver);
+}
+module_exit(csr_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CoreSight CSR driver");
diff --git a/drivers/hwtracing/coresight/coresight-csr.h b/drivers/hwtracing/coresight/coresight-csr.h
new file mode 100644
index 000000000000..3fd24b8e28e8
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-csr.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef _CORESIGHT_CSR_H
+#define _CORESIGHT_CSR_H
+#include <linux/clk.h>
+#include <linux/coresight.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+
+struct coresight_csr {
+	const char *name;
+	struct list_head link;
+};
+
+/**
+ * struct csr_drvdata - specifics for the CSR device.
+ * @base:	Memory mapped base address for this component.
+ * @pbase:	Physical address base.
+ * @dev:	The device entity associated to this component.
+ * @csdev:	Data struct for coresight device.
+ * @csr:	CSR struct
+ * @clk:	Clock of this component.
+ * @spin_lock:	Spin lock for the data.
+ */
+struct csr_drvdata {
+	void __iomem		*base;
+	phys_addr_t		pbase;
+	struct device		*dev;
+	struct coresight_device	*csdev;
+	struct coresight_csr	csr;
+	struct clk		*clk;
+	spinlock_t		spin_lock;
+};
+#if IS_ENABLED(CONFIG_CORESIGHT_CSR)
+extern void coresight_csr_set_byte_cntr(struct coresight_csr *csr, uint32_t count);
+extern struct coresight_csr *coresight_csr_get(const char *name);
+#if IS_ENABLED(CONFIG_OF)
+extern int of_get_coresight_csr_name(struct device_node *node,
+				const char **csr_name);
+#else
+static inline int of_get_coresight_csr_name(struct device_node *node,
+		const char **csr_name){ return -EINVAL; }
+#endif
+#else
+static inline void coresight_csr_set_byte_cntr(struct coresight_csr *csr, int irqctrl_offset,
+					   uint32_t count) {}
+static inline struct coresight_csr *coresight_csr_get(const char *name)
+					{ return NULL; }
+#endif
+#endif
+
-- 
2.17.1