1 files changed, 326 insertions, 0 deletions
diff --git a/drivers/hwtracing/coresight/coresight-ctcu-core.c b/drivers/hwtracing/coresight/coresight-ctcu-core.c
new file mode 100644
index 000000000000..c6bafc96db96
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-ctcu-core.c
@@ -0,0 +1,326 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024-2025 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/clk.h>
+#include <linux/coresight.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#include "coresight-ctcu.h"
+#include "coresight-priv.h"
+
+DEFINE_CORESIGHT_DEVLIST(ctcu_devs, "ctcu");
+
+#define ctcu_writel(drvdata, val, offset)	__raw_writel((val), drvdata->base + offset)
+#define ctcu_readl(drvdata, offset)		__raw_readl(drvdata->base + offset)
+
+/*
+ * The TMC Coresight Control Unit utilizes four ATID registers to control the data
+ * filter function based on the trace ID for each TMC ETR sink. The length of each
+ * ATID register is 32 bits. Therefore, an ETR device has a 128-bit long field
+ * in CTCU. Each trace ID is represented by one bit in that filed.
+ * e.g. ETR0ATID0 layout, set bit 5 for traceid 5
+ *                                           bit5
+ * ------------------------------------------------------
+ * |   |28|   |24|   |20|   |16|   |12|   |8|  1|4|   |0|
+ * ------------------------------------------------------
+ *
+ * e.g. ETR0:
+ * 127                     0 from ATID_offset for ETR0ATID0
+ * -------------------------
+ * |ATID3|ATID2|ATID1|ATID0|
+ */
+#define CTCU_ATID_REG_OFFSET(traceid, atid_offset) \
+		((traceid / 32) * 4 + atid_offset)
+
+#define CTCU_ATID_REG_BIT(traceid)	(traceid % 32)
+#define CTCU_ATID_REG_SIZE		0x10
+#define CTCU_ETR0_ATID0			0xf8
+#define CTCU_ETR1_ATID0			0x108
+
+static const struct ctcu_etr_config sa8775p_etr_cfgs[] = {
+	{
+		.atid_offset	= CTCU_ETR0_ATID0,
+		.port_num	= 0,
+	},
+	{
+		.atid_offset	= CTCU_ETR1_ATID0,
+		.port_num	= 1,
+	},
+};
+
+static const struct ctcu_config sa8775p_cfgs = {
+	.etr_cfgs	= sa8775p_etr_cfgs,
+	.num_etr_config	= ARRAY_SIZE(sa8775p_etr_cfgs),
+};
+
+static void ctcu_program_atid_register(struct ctcu_drvdata *drvdata, u32 reg_offset,
+				       u8 bit, bool enable)
+{
+	u32 val;
+
+	CS_UNLOCK(drvdata->base);
+	val = ctcu_readl(drvdata, reg_offset);
+	if (enable)
+		val |= BIT(bit);
+	else
+		val &= ~BIT(bit);
+
+	ctcu_writel(drvdata, val, reg_offset);
+	CS_LOCK(drvdata->base);
+}
+
+/*
+ * __ctcu_set_etr_traceid: Set bit in the ATID register based on trace ID when enable is true.
+ * Reset the bit of the ATID register based on trace ID when enable is false.
+ *
+ * @csdev:	coresight_device of CTCU.
+ * @traceid:	trace ID of the source tracer.
+ * @port_num:	port number connected to TMC ETR sink.
+ * @enable:	True for set bit and false for reset bit.
+ *
+ * Returns 0 indicates success. Non-zero result means failure.
+ */
+static int __ctcu_set_etr_traceid(struct coresight_device *csdev, u8 traceid, int port_num,
+				  bool enable)
+{
+	struct ctcu_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	u32 atid_offset, reg_offset;
+	u8 refcnt, bit;
+
+	atid_offset = drvdata->atid_offset[port_num];
+	if (atid_offset == 0)
+		return -EINVAL;
+
+	bit = CTCU_ATID_REG_BIT(traceid);
+	reg_offset = CTCU_ATID_REG_OFFSET(traceid, atid_offset);
+	if (reg_offset - atid_offset > CTCU_ATID_REG_SIZE)
+		return -EINVAL;
+
+	guard(raw_spinlock_irqsave)(&drvdata->spin_lock);
+	refcnt = drvdata->traceid_refcnt[port_num][traceid];
+	/* Only program the atid register when the refcnt value is 1 or 0 */
+	if ((enable && !refcnt++) || (!enable && !--refcnt))
+		ctcu_program_atid_register(drvdata, reg_offset, bit, enable);
+
+	drvdata->traceid_refcnt[port_num][traceid] = refcnt;
+
+	return 0;
+}
+
+/*
+ * Searching the sink device from helper's view in case there are multiple helper devices
+ * connected to the sink device.
+ */
+static int ctcu_get_active_port(struct coresight_device *sink, struct coresight_device *helper)
+{
+	struct coresight_platform_data *pdata = helper->pdata;
+	int i;
+
+	for (i = 0; i < pdata->nr_inconns; ++i) {
+		if (pdata->in_conns[i]->src_dev == sink)
+			return pdata->in_conns[i]->dest_port;
+	}
+
+	return -EINVAL;
+}
+
+static int ctcu_set_etr_traceid(struct coresight_device *csdev, struct coresight_path *path,
+				bool enable)
+{
+	struct coresight_device *sink = coresight_get_sink(path);
+	u8 traceid = path->trace_id;
+	int port_num;
+
+	if ((sink == NULL) || !IS_VALID_CS_TRACE_ID(traceid)) {
+		dev_err(&csdev->dev, "Invalid sink device or trace ID\n");
+		return -EINVAL;
+	}
+
+	port_num = ctcu_get_active_port(sink, csdev);
+	if (port_num < 0)
+		return -EINVAL;
+
+	dev_dbg(&csdev->dev, "traceid is %d\n", traceid);
+
+	return __ctcu_set_etr_traceid(csdev, traceid, port_num, enable);
+}
+
+static int ctcu_enable(struct coresight_device *csdev, enum cs_mode mode, void *data)
+{
+	struct coresight_path *path = (struct coresight_path *)data;
+
+	return ctcu_set_etr_traceid(csdev, path, true);
+}
+
+static int ctcu_disable(struct coresight_device *csdev, void *data)
+{
+	struct coresight_path *path = (struct coresight_path *)data;
+
+	return ctcu_set_etr_traceid(csdev, path, false);
+}
+
+static const struct coresight_ops_helper ctcu_helper_ops = {
+	.enable = ctcu_enable,
+	.disable = ctcu_disable,
+};
+
+static const struct coresight_ops ctcu_ops = {
+	.helper_ops = &ctcu_helper_ops,
+};
+
+static int ctcu_probe(struct platform_device *pdev)
+{
+	const struct ctcu_etr_config *etr_cfg;
+	struct coresight_platform_data *pdata;
+	struct coresight_desc desc = { 0 };
+	struct device *dev = &pdev->dev;
+	const struct ctcu_config *cfgs;
+	struct ctcu_drvdata *drvdata;
+	void __iomem *base;
+	int i;
+
+	desc.name = coresight_alloc_device_name(&ctcu_devs, dev);
+	if (!desc.name)
+		return -ENOMEM;
+
+	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata)
+		return -ENOMEM;
+
+	pdata = coresight_get_platform_data(dev);
+	if (IS_ERR(pdata))
+		return PTR_ERR(pdata);
+	dev->platform_data = pdata;
+
+	base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	drvdata->apb_clk = coresight_get_enable_apb_pclk(dev);
+	if (IS_ERR(drvdata->apb_clk))
+		return -ENODEV;
+
+	cfgs = of_device_get_match_data(dev);
+	if (cfgs) {
+		if (cfgs->num_etr_config <= ETR_MAX_NUM) {
+			for (i = 0; i < cfgs->num_etr_config; i++) {
+				etr_cfg = &cfgs->etr_cfgs[i];
+				drvdata->atid_offset[i] = etr_cfg->atid_offset;
+			}
+		}
+	}
+
+	drvdata->base = base;
+	drvdata->dev = dev;
+	platform_set_drvdata(pdev, drvdata);
+
+	desc.type = CORESIGHT_DEV_TYPE_HELPER;
+	desc.subtype.helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_CTCU;
+	desc.pdata = pdata;
+	desc.dev = dev;
+	desc.ops = &ctcu_ops;
+	desc.access = CSDEV_ACCESS_IOMEM(base);
+
+	drvdata->csdev = coresight_register(&desc);
+	if (IS_ERR(drvdata->csdev)) {
+		if (!IS_ERR_OR_NULL(drvdata->apb_clk))
+			clk_put(drvdata->apb_clk);
+
+		return PTR_ERR(drvdata->csdev);
+	}
+
+	return 0;
+}
+
+static void ctcu_remove(struct platform_device *pdev)
+{
+	struct ctcu_drvdata *drvdata = platform_get_drvdata(pdev);
+
+	coresight_unregister(drvdata->csdev);
+}
+
+static int ctcu_platform_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	pm_runtime_get_noresume(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	ret = ctcu_probe(pdev);
+	pm_runtime_put(&pdev->dev);
+	if (ret)
+		pm_runtime_disable(&pdev->dev);
+
+	return ret;
+}
+
+static void ctcu_platform_remove(struct platform_device *pdev)
+{
+	struct ctcu_drvdata *drvdata = platform_get_drvdata(pdev);
+
+	if (WARN_ON(!drvdata))
+		return;
+
+	ctcu_remove(pdev);
+	pm_runtime_disable(&pdev->dev);
+	if (!IS_ERR_OR_NULL(drvdata->apb_clk))
+		clk_put(drvdata->apb_clk);
+}
+
+#ifdef CONFIG_PM
+static int ctcu_runtime_suspend(struct device *dev)
+{
+	struct ctcu_drvdata *drvdata = dev_get_drvdata(dev);
+
+	if (drvdata && !IS_ERR_OR_NULL(drvdata->apb_clk))
+		clk_disable_unprepare(drvdata->apb_clk);
+
+	return 0;
+}
+
+static int ctcu_runtime_resume(struct device *dev)
+{
+	struct ctcu_drvdata *drvdata = dev_get_drvdata(dev);
+
+	if (drvdata && !IS_ERR_OR_NULL(drvdata->apb_clk))
+		clk_prepare_enable(drvdata->apb_clk);
+
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops ctcu_dev_pm_ops = {
+	SET_RUNTIME_PM_OPS(ctcu_runtime_suspend, ctcu_runtime_resume, NULL)
+};
+
+static const struct of_device_id ctcu_match[] = {
+	{.compatible = "qcom,sa8775p-ctcu", .data = &sa8775p_cfgs},
+	{}
+};
+
+static struct platform_driver ctcu_driver = {
+	.probe          = ctcu_platform_probe,
+	.remove         = ctcu_platform_remove,
+	.driver         = {
+		.name   = "coresight-ctcu",
+		.of_match_table = ctcu_match,
+		.pm	= &ctcu_dev_pm_ops,
+		.suppress_bind_attrs = true,
+	},
+};
+module_platform_driver(ctcu_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CoreSight TMC Control Unit driver");