Re: [PATCH v11 2/2] coresight: add coresight Trace Network On Chip driver

On Thu, 10 Jul 2025 at 06:28, Yuanfang Zhang quic_yuanfang@quicinc.com wrote:

Add a driver to support Coresight device Trace Network On Chip (TNOC), which is an integration hierarchy integrating functionalities of TPDA and funnels. It aggregates the trace and transports to coresight trace bus.

Compared to current configuration, it has the following advantages:

1. Reduce wires between subsystems.
2. Continue cleaning the infrastructure.
3. Reduce Data overhead by transporting raw data from source to target.

+------------------------+ +-------------------------+ | Video Subsystem | |Video Subsystem | | +-------------+ | | +------------+ | | | Video TPDM | | | | Video TPDM | | | +-------------+ | | +------------+ | | | | | | | | v | | v | | +---------------+ | | +-----------+ | | | Video funnel | | | |Video TNOC | | | +---------------+ | | +-----------+ | +------------|-----------+ +------------|------------+ | | v-----+ | +--------------------|---------+ | | Multimedia v | | | Subsystem +--------+ | | | | TPDA | | v | +----|---+ | +---------------------+ | | | | Aggregator TNOC | | | | +----------|----------+ | +-- | | | | | | | | | | | +------v-----+ | | | | Funnel | | | | +------------+ | | +----------------|-------------+ | | | v v +--------------------+ +------------------+ | Coresight Sink | | Coresight Sink | +--------------------+ +------------------+

   Current Configuration                            TNOC

Reviewed-by: Leo Yan leo.yan@arm.com Signed-off-by: Yuanfang Zhang quic_yuanfang@quicinc.com

---

drivers/hwtracing/coresight/Kconfig | 12 ++ drivers/hwtracing/coresight/Makefile | 1 + drivers/hwtracing/coresight/coresight-tnoc.c | 242 +++++++++++++++++++++++++++ 3 files changed, 255 insertions(+)

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig index f064e3d172b3d630515bb3a11450e883a6b5b4bf..6a4239ebb582e95f0ebe8e9c8738a726f27f60a1 100644 --- a/drivers/hwtracing/coresight/Kconfig +++ b/drivers/hwtracing/coresight/Kconfig @@ -268,4 +268,16 @@ config CORESIGHT_KUNIT_TESTS Enable Coresight unit tests. Only useful for development and not intended for production.

+config CORESIGHT_TNOC

•   tristate "Coresight Trace Network On Chip driver"
  

•   help
  

•     This driver provides support for Trace Network On Chip (TNOC) component.
  

•     TNOC is an interconnect used to collect traces from various subsystems
  

•     and transport to a coresight trace sink. It sits in the different
  

•     tiles of SOC and aggregates the trace local to the tile and transports
  

•     it another tile or to coresight trace sink eventually.
  

•     To compile this driver as a module, choose M here: the module will be
  

•     called coresight-tnoc.
  

endif diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index 4e7cc3c5bf994d4066adc3b6c203edd19e88a823..ab16d06783a572ea1308dfb3a30c96df9e5ffdb7 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_CORESIGHT_SINK_TPIU) += coresight-tpiu.o obj-$(CONFIG_CORESIGHT_SINK_ETBV10) += coresight-etb10.o obj-$(CONFIG_CORESIGHT_LINKS_AND_SINKS) += coresight-funnel.o \ coresight-replicator.o +obj-$(CONFIG_CORESIGHT_TNOC) += coresight-tnoc.o obj-$(CONFIG_CORESIGHT_SOURCE_ETM3X) += coresight-etm3x.o coresight-etm3x-y := coresight-etm3x-core.o coresight-etm-cp14.o \ coresight-etm3x-sysfs.o diff --git a/drivers/hwtracing/coresight/coresight-tnoc.c b/drivers/hwtracing/coresight/coresight-tnoc.c new file mode 100644 index 0000000000000000000000000000000000000000..0e4164707eea974e6f34d2de01693354d6eefdcd --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-tnoc.c @@ -0,0 +1,242 @@ +// SPDX-License-Identifier: GPL-2.0-only +/*

• • Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved.
• */
• #include <linux/amba/bus.h>
• #include <linux/coresight.h>
• #include <linux/device.h>
• #include <linux/io.h>
• #include <linux/kernel.h>
• #include <linux/module.h>
• #include <linux/of.h>
• #include <linux/platform_device.h>

+#include "coresight-priv.h" +#include "coresight-trace-id.h"

+#define TRACE_NOC_CTRL 0x008 +#define TRACE_NOC_XLD 0x010 +#define TRACE_NOC_FREQVAL 0x018 +#define TRACE_NOC_SYNCR 0x020

+/* Enable generation of output ATB traffic.*/ +#define TRACE_NOC_CTRL_PORTEN BIT(0) +/* Sets the type of issued ATB FLAG packets.*/ +#define TRACE_NOC_CTRL_FLAGTYPE BIT(7) +/* Sets the type of issued ATB FREQ packet*/ +#define TRACE_NOC_CTRL_FREQTYPE BIT(8)

+#define TRACE_NOC_SYNC_INTERVAL 0xFFFF

+/*

• • struct trace_noc_drvdata - specifics associated to a trace noc component
• • @base: memory mapped base address for this component.
• • @dev: device node for trace_noc_drvdata.
• • @csdev: component vitals needed by the framework.
• • @spinlock: serialize enable/disable operation.
• • @atid: id for the trace packet.
• */

+struct trace_noc_drvdata {

•   void __iomem            *base;
  

•   struct device           *dev;
  

•   struct coresight_device *csdev;
  

•   spinlock_t              spinlock;
  

•   u32                     atid;
  

+};

+DEFINE_CORESIGHT_DEVLIST(trace_noc_devs, "traceNoc");

+static void trace_noc_enable_hw(struct trace_noc_drvdata *drvdata) +{

•   u32 val;
  

•   /* Set ATID */
  

•   writel_relaxed(drvdata->atid, drvdata->base + TRACE_NOC_XLD);
  

•   /* Set the data word count between 'SYNC' packets */
  

•   writel_relaxed(TRACE_NOC_SYNC_INTERVAL, drvdata->base + TRACE_NOC_SYNCR);
  

•   /* Set the Control register:
  

•    * - Set the FLAG packets to 'FLAG' packets
  

•    * - Set the FREQ packets to 'FREQ_TS' packets
  

•    * - Enable generation of output ATB traffic
  

•    */
  

•   val = readl_relaxed(drvdata->base + TRACE_NOC_CTRL);
  

•   val &= ~TRACE_NOC_CTRL_FLAGTYPE;
  

•   val |= TRACE_NOC_CTRL_FREQTYPE;
  

•   val |= TRACE_NOC_CTRL_PORTEN;
  

•   writel(val, drvdata->base + TRACE_NOC_CTRL);
  

+}

+static int trace_noc_enable(struct coresight_device *csdev, struct coresight_connection *inport,

•                       struct coresight_connection *outport)
  

+{

•   struct trace_noc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  

•   scoped_guard(spinlock, &drvdata->spinlock) {
  

•           if (csdev->refcnt == 0)
  

•                   trace_noc_enable_hw(drvdata);
  

•           csdev->refcnt++;
  

•   }
  

•   dev_dbg(drvdata->dev, "Trace NOC is enabled\n");
  

•   return 0;
  

+}

+static void trace_noc_disable(struct coresight_device *csdev, struct coresight_connection *inport,

•                         struct coresight_connection *outport)
  

+{

•   struct trace_noc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
  

•   scoped_guard(spinlock, &drvdata->spinlock) {
  

•           if (--csdev->refcnt == 0)
  

•                   writel(0x0, drvdata->base + TRACE_NOC_CTRL);
  

•   }
  

•   dev_dbg(drvdata->dev, "Trace NOC is disabled\n");
  

+}

+static int trace_noc_id(struct coresight_device *csdev, __maybe_unused enum cs_mode mode,

•                   __maybe_unused struct coresight_device *sink)
  

+{

•   struct trace_noc_drvdata *drvdata;
  

•   drvdata = dev_get_drvdata(csdev->dev.parent);
  

•   return drvdata->atid;
  

+}

+static const struct coresight_ops_link trace_noc_link_ops = {

•   .enable         = trace_noc_enable,
  

•   .disable        = trace_noc_disable,
  

+};

+static const struct coresight_ops trace_noc_cs_ops = {

•   .trace_id       = trace_noc_id,
  

•   .link_ops       = &trace_noc_link_ops,
  

+};

+static int trace_noc_init_default_data(struct trace_noc_drvdata *drvdata) +{

•   int atid;
  

•   atid = coresight_trace_id_get_system_id();
  

•   if (atid < 0)
  

•           return atid;
  

•   drvdata->atid = atid;
  

•   return 0;
  

+}

+static ssize_t traceid_show(struct device *dev,

•                       struct device_attribute *attr, char *buf)
  

+{

•   unsigned long val;
  

•   struct trace_noc_drvdata *drvdata = dev_get_drvdata(dev->parent);
  

•   val = drvdata->atid;
  

•   return sprintf(buf, "%#lx\n", val);
  

+} +static DEVICE_ATTR_RO(traceid);

+static struct attribute *coresight_tnoc_attrs[] = {

•   &dev_attr_traceid.attr,
  

•   NULL,
  

+};

+static const struct attribute_group coresight_tnoc_group = {

•   .attrs = coresight_tnoc_attrs,
  

+};

+static const struct attribute_group *coresight_tnoc_groups[] = {

•   &coresight_tnoc_group,
  

•   NULL,
  

+};

+static int trace_noc_probe(struct amba_device *adev, const struct amba_id *id) +{

•   struct device *dev = &adev->dev;
  

•   struct coresight_platform_data *pdata;
  

•   struct trace_noc_drvdata *drvdata;
  

•   struct coresight_desc desc = { 0 };
  

•   int ret;
  

•   desc.name = coresight_alloc_device_name(&trace_noc_devs, dev);
  

•   if (!desc.name)
  

•           return -ENOMEM;
  

•   pdata = coresight_get_platform_data(dev);
  

•   if (IS_ERR(pdata))
  

•           return PTR_ERR(pdata);
  

•   adev->dev.platform_data = pdata;
  

•   drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
  

•   if (!drvdata)
  

•           return -ENOMEM;
  

•   drvdata->dev = &adev->dev;
  

•   dev_set_drvdata(dev, drvdata);
  

•   drvdata->base = devm_ioremap_resource(dev, &adev->res);
  

•   if (!drvdata->base)
  

•           return -ENOMEM;
  

•   spin_lock_init(&drvdata->spinlock);
  

•   ret = trace_noc_init_default_data(drvdata);
  

•   if (ret)
  

•           return ret;
  

•   desc.ops = &trace_noc_cs_ops;
  

•   desc.type = CORESIGHT_DEV_TYPE_LINK;
  

•   desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG;
  

•   desc.pdata = adev->dev.platform_data;
  

•   desc.dev = &adev->dev;
  

•   desc.access = CSDEV_ACCESS_IOMEM(drvdata->base);
  

•   desc.groups = coresight_tnoc_groups;
  

•   drvdata->csdev = coresight_register(&desc);
  

•   if (IS_ERR(drvdata->csdev)) {
  

•           coresight_trace_id_put_system_id(drvdata->atid);
  

•           return PTR_ERR(drvdata->csdev);
  

•   }
  

•   pm_runtime_put(&adev->dev);
  

•   return 0;
  

+}

+static void trace_noc_remove(struct amba_device *adev) +{

•   struct trace_noc_drvdata *drvdata = dev_get_drvdata(&adev->dev);
  

•   coresight_unregister(drvdata->csdev);
  

•   coresight_trace_id_put_system_id(drvdata->atid);
  

+}

+static struct amba_id trace_noc_ids[] = {

•   {
  

•           .id     = 0x000f0c00,
  

•           .mask   = 0x00ffff00,
  

•   },
  

•   {},
  

+}; +MODULE_DEVICE_TABLE(amba, trace_noc_ids);

+static struct amba_driver trace_noc_driver = {

•   .drv = {
  

•           .name   = "coresight-trace-noc",
  

•           .suppress_bind_attrs = true,
  

•   },
  

•   .probe          = trace_noc_probe,
  

•   .remove         = trace_noc_remove,
  

•   .id_table       = trace_noc_ids,
  

+};

+module_amba_driver(trace_noc_driver);

+MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Trace NOC driver");

-- 2.34.1

Reviewed-by: Mike Leach mike.leach@linaro.com