From: liangzhen zhen.liang@spacemit.com
Add initial implementation of RISC-V trace funnel driver. The funnel is defined in the RISC-V Trace Control Interface specification.
Signed-off-by: liangzhen zhen.liang@spacemit.com --- drivers/hwtracing/coresight/Kconfig | 12 + drivers/hwtracing/coresight/Makefile | 1 + drivers/hwtracing/coresight/rvtrace-funnel.c | 244 +++++++++++++++++++ drivers/hwtracing/coresight/rvtrace-funnel.h | 31 +++ 4 files changed, 288 insertions(+) create mode 100644 drivers/hwtracing/coresight/rvtrace-funnel.c create mode 100644 drivers/hwtracing/coresight/rvtrace-funnel.h
diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig index 3e46728f2482..8381a84e2699 100644 --- a/drivers/hwtracing/coresight/Kconfig +++ b/drivers/hwtracing/coresight/Kconfig @@ -288,9 +288,21 @@ config RVTRACE dynamically aggregated with CoreSight trace infrastructure at run time to form a complete trace path.
+config RVTRACE_FUNNEL + tristate "RISCV Trace Funnel driver" + depends on RVTRACE + help + his driver provides support for the Trace Funnel driver. The Funnel + aggregates the trace from each of its inputs and sends the combined + trace stream to its designated Trace Sink or ATB Bridge. + + To compile this driver as a module, choose M here: the module + will be called rvtrace-funnel. + config RVTRACE_ENCODER tristate "RISCV Trace Encoder driver" depends on RVTRACE + select RVTRACE_FUNNEL help This driver provides support for the Trace Encoder module, tracing the instructions that a processor is executing. This is primarily diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index 9a526b1fb95a..409a0abf0642 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -59,5 +59,6 @@ coresight-ctcu-y := coresight-ctcu-core.o obj-$(CONFIG_CORESIGHT_KUNIT_TESTS) += coresight-kunit-tests.o obj-$(CONFIG_RVTRACE) += rvtrace.o rvtrace-y := rvtrace-core.o +obj-$(CONFIG_RVTRACE_FUNNEL) += rvtrace-funnel.o obj-$(CONFIG_RVTRACE_ENCODER) += rvtrace-encoder.o rvtrace-encoder-y := rvtrace-encoder-core.o rvtrace-encoder-sysfs.o diff --git a/drivers/hwtracing/coresight/rvtrace-funnel.c b/drivers/hwtracing/coresight/rvtrace-funnel.c new file mode 100644 index 000000000000..0dc7799a64ac --- /dev/null +++ b/drivers/hwtracing/coresight/rvtrace-funnel.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright(C) 2026 Spacemit Limited. All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/coresight.h> +#include <linux/platform_device.h> +#include <linux/rvtrace.h> + +#include "coresight-priv.h" +#include "rvtrace-funnel.h" + +DEFINE_CORESIGHT_DEVLIST(funnel_devs, "rvtrace_funnel"); + +static int funnel_enable_hw(struct rvtrace_component *comp, int port) +{ + u32 disinput; + int ret = 0; + struct funnel_data *funnel_data = rvtrace_component_data(comp); + + if (!comp->was_reset) { + ret = rvtrace_component_reset(comp); + if (ret) + goto done; + } + + disinput = readl_relaxed(comp->base + RVTRACE_FUNNEL_DISINPUT_OFFSET); + disinput &= ~(1 << port); + writel_relaxed(disinput, comp->base + RVTRACE_FUNNEL_DISINPUT_OFFSET); + ret = rvtrace_poll_bit(comp, RVTRACE_FUNNEL_DISINPUT_OFFSET, port, 0); + if (ret) + goto done; + + if (!funnel_data->was_enabled) { + ret = rvtrace_enable_component(comp); + if (ret) + goto done; + } + +done: + return ret; +} + +static int funnel_enable(struct coresight_device *csdev, + struct coresight_connection *in, + struct coresight_connection *out) +{ + int ret = 0; + struct rvtrace_component *comp = dev_get_drvdata(csdev->dev.parent); + struct funnel_data *funnel_data = rvtrace_component_data(comp); + unsigned long flags; + bool first_enable = false; + + spin_lock_irqsave(&funnel_data->spinlock, flags); + if (in->dest_refcnt == 0) { + ret = funnel_enable_hw(comp, in->dest_port); + if (!ret) + first_enable = true; + } + if (!ret) { + in->dest_refcnt++; + funnel_data->input_refcnt++; + } + + if (first_enable) + dev_dbg(&csdev->dev, "Trace funnel inport %d enabled\n", + in->dest_port); + + spin_unlock_irqrestore(&funnel_data->spinlock, flags); + + return ret; +} + +static void funnel_disable_hw(struct rvtrace_component *comp, int inport) +{ + struct funnel_data *funnel_data = rvtrace_component_data(comp); + + if (--funnel_data->input_refcnt != 0) + return; + + writel_relaxed(RVTRACE_FUNNEL_DISINPUT_MASK, comp->base + RVTRACE_FUNNEL_DISINPUT_OFFSET); + + if (rvtrace_disable_component(comp)) + dev_err(&funnel_data->csdev->dev, + "timeout while waiting for Trace Funnel to be disabled\n"); + + if (rvtrace_comp_is_empty(comp)) + dev_err(&funnel_data->csdev->dev, + "timeout while waiting for Trace Funnel internal buffers become empty\n"); +} + +static void funnel_disable(struct coresight_device *csdev, + struct coresight_connection *in, + struct coresight_connection *out) +{ + struct rvtrace_component *comp = dev_get_drvdata(csdev->dev.parent); + struct funnel_data *funnel_data = rvtrace_component_data(comp); + unsigned long flags; + bool last_disable = false; + + spin_lock_irqsave(&funnel_data->spinlock, flags); + if (--in->dest_refcnt == 0) { + funnel_disable_hw(comp, in->dest_port); + last_disable = true; + } + spin_unlock_irqrestore(&funnel_data->spinlock, flags); + + if (last_disable) + dev_dbg(&csdev->dev, "Trace funnel inport %d disabled\n", + in->dest_port); + + if (funnel_data->input_refcnt == 0) + dev_dbg(&csdev->dev, "Trace funnel disabled\n"); +} + +static const struct coresight_ops_link funnel_link_ops = { + .enable = funnel_enable, + .disable = funnel_disable, +}; + +static const struct coresight_ops funnel_cs_ops = { + .link_ops = &funnel_link_ops, +}; + +static ssize_t reset_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + unsigned long val; + struct rvtrace_component *comp = dev_get_drvdata(dev->parent); + struct funnel_data *funnel_data = rvtrace_component_data(comp); + unsigned long flags; + + if (kstrtoul(buf, 16, &val)) + return -EINVAL; + + spin_lock_irqsave(&funnel_data->spinlock, flags); + + if (val) { + if (rvtrace_component_reset(comp)) { + comp->was_reset = false; + spin_unlock_irqrestore(&funnel_data->spinlock, flags); + return -EINVAL; + } + } + + spin_unlock_irqrestore(&funnel_data->spinlock, flags); + + return size; +} +static DEVICE_ATTR_WO(reset); + +static ssize_t cpu_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long val; + struct rvtrace_component *comp = dev_get_drvdata(dev->parent); + + val = comp->cpu; + return scnprintf(buf, PAGE_SIZE, "%#lx\n", val); +} +static DEVICE_ATTR_RO(cpu); + +static struct attribute *trace_funnel_attrs[] = { + coresight_simple_reg32(control, RVTRACE_COMPONENT_CTRL_OFFSET), + coresight_simple_reg32(impl, RVTRACE_COMPONENT_IMPL_OFFSET), + coresight_simple_reg32(disinput, RVTRACE_FUNNEL_DISINPUT_OFFSET), + &dev_attr_reset.attr, + &dev_attr_cpu.attr, + NULL, +}; +ATTRIBUTE_GROUPS(trace_funnel); + +static int funnel_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct coresight_platform_data *pdata; + struct funnel_data *funnel_data; + struct rvtrace_component *comp; + struct coresight_desc desc = { 0 }; + + comp = rvtrace_register_component(pdev); + if (IS_ERR(comp)) + return PTR_ERR(comp); + + funnel_data = devm_kzalloc(dev, sizeof(*funnel_data), GFP_KERNEL); + if (!funnel_data) + return -ENOMEM; + + spin_lock_init(&funnel_data->spinlock); + + pdata = coresight_get_platform_data(dev); + if (IS_ERR(pdata)) + return PTR_ERR(pdata); + pdev->dev.platform_data = pdata; + + platform_set_drvdata(pdev, comp); + + desc.name = coresight_alloc_device_name(&funnel_devs, dev); + desc.access = CSDEV_ACCESS_IOMEM(comp->base); + desc.type = CORESIGHT_DEV_TYPE_LINK; + desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_MERG; + desc.ops = &funnel_cs_ops; + desc.pdata = pdata; + desc.dev = dev; + desc.groups = trace_funnel_groups; + funnel_data->csdev = coresight_register(&desc); + if (IS_ERR(funnel_data->csdev)) + return PTR_ERR(funnel_data->csdev); + + comp->id.data = funnel_data; + + dev_dbg(dev, "Trace Funnel initialized\n"); + + return 0; +} + +static void funnel_remove(struct platform_device *pdev) +{ + struct rvtrace_component *comp = platform_get_drvdata(pdev); + struct funnel_data *funnel_data = rvtrace_component_data(comp); + + coresight_unregister(funnel_data->csdev); +} + +static const struct of_device_id funnel_match[] = { + {.compatible = "riscv,trace-funnel"}, + {}, +}; + +static struct platform_driver funnel_driver = { + .probe = funnel_probe, + .remove = funnel_remove, + .driver = { + .name = "trace-funnel", + .of_match_table = funnel_match, + }, +}; + +module_platform_driver(funnel_driver); + +MODULE_DESCRIPTION("RISC-V Trace funnel driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/hwtracing/coresight/rvtrace-funnel.h b/drivers/hwtracing/coresight/rvtrace-funnel.h new file mode 100644 index 000000000000..e5247e6c1bf5 --- /dev/null +++ b/drivers/hwtracing/coresight/rvtrace-funnel.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright(C) 2026 Spacemit Limited. All rights reserved. + */ + +#ifndef _RVTRACE_FUNNEL_H +#define _RVTRACE_FUNNEL_H + +#include <linux/spinlock.h> +#include <linux/coresight.h> + +/* Disable Individual Funnel Inputs */ +#define RVTRACE_FUNNEL_DISINPUT_OFFSET 0x008 +#define RVTRACE_FUNNEL_DISINPUT_MASK 0xffff + +/** + * struct funnel_data - specifics associated to a Trace Funnel component + * @csdev: Component vitals needed by the framework. + * @spinlock: Only one at a time pls. + * @was_enabled: Flag showing whether the Trace Funnel was enabled. + * @input_refcnt: Record the number of funnel inputs + */ +struct funnel_data { + struct coresight_device *csdev; + spinlock_t spinlock; + bool was_enabled; + u32 input_refcnt; + u32 disintput; +}; + +#endif