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Message-ID: <36eea2f6-3461-72ad-05c4-953484197911@huawei.com>
Date: Mon, 11 Apr 2022 18:02:19 +0100
From: John Garry <john.garry@...wei.com>
To: Yicong Yang <yangyicong@...ilicon.com>,
<gregkh@...uxfoundation.org>, <helgaas@...nel.org>,
<alexander.shishkin@...ux.intel.com>, <lorenzo.pieralisi@....com>,
<will@...nel.org>, <mark.rutland@....com>,
<mathieu.poirier@...aro.org>, <suzuki.poulose@....com>,
<mike.leach@...aro.org>, <leo.yan@...aro.org>,
<jonathan.cameron@...wei.com>, <daniel.thompson@...aro.org>,
<joro@...tes.org>, <shameerali.kolothum.thodi@...wei.com>,
<robin.murphy@....com>, <peterz@...radead.org>, <mingo@...hat.com>,
<acme@...nel.org>, <linux-kernel@...r.kernel.org>,
<linux-arm-kernel@...ts.infradead.org>,
<coresight@...ts.linaro.org>, <linux-pci@...r.kernel.org>,
<linux-perf-users@...r.kernel.org>,
<iommu@...ts.linux-foundation.org>
CC: <prime.zeng@...wei.com>, <liuqi115@...wei.com>,
<zhangshaokun@...ilicon.com>, <linuxarm@...wei.com>
Subject: Re: [PATCH v7 2/7] hwtracing: Add trace function support for
HiSilicon PCIe Tune and Trace device
On 07/04/2022 13:58, Yicong Yang wrote:
> HiSilicon PCIe tune and trace device(PTT) is a PCIe Root Complex integrated
> Endpoint(RCiEP) device, providing the capability to dynamically monitor and
> tune the PCIe traffic, and trace the TLP headers.
>
> Add the driver for the device to enable the trace function. Register PMU
> device of PTT trace, then users can use trace through perf command. The
> driver makes use of perf AUX trace and support following events to
"The driver makes use of perf AUX trace function and supports the
following events to .."
> configure the trace:
>
> - filter: select Root port or Endpoint to trace
> - type: select the type of traced TLP headers
> - direction: select the direction of traced TLP headers
> - format: select the data format of the traced TLP headers
>
> This patch adds the driver part of PTT trace. The perf command support of
> PTT trace is added in the following patch.
I would not mention "following patch" and the like. Just have "initially
add a basic driver"
>
> Signed-off-by: Yicong Yang <yangyicong@...ilicon.com>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@...wei.com>
> ---
> drivers/Makefile | 1 +
> drivers/hwtracing/Kconfig | 2 +
> drivers/hwtracing/ptt/Kconfig | 12 +
> drivers/hwtracing/ptt/Makefile | 2 +
> drivers/hwtracing/ptt/hisi_ptt.c | 874 +++++++++++++++++++++++++++++++
> drivers/hwtracing/ptt/hisi_ptt.h | 166 ++++++
> 6 files changed, 1057 insertions(+)
> create mode 100644 drivers/hwtracing/ptt/Kconfig
> create mode 100644 drivers/hwtracing/ptt/Makefile
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.c
> create mode 100644 drivers/hwtracing/ptt/hisi_ptt.h
>
> diff --git a/drivers/Makefile b/drivers/Makefile
> index 020780b6b4d2..662d50599467 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -175,6 +175,7 @@ obj-$(CONFIG_USB4) += thunderbolt/
> obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/
> obj-y += hwtracing/intel_th/
> obj-$(CONFIG_STM) += hwtracing/stm/
> +obj-$(CONFIG_HISI_PTT) += hwtracing/ptt/
> obj-$(CONFIG_ANDROID) += android/
> obj-$(CONFIG_NVMEM) += nvmem/
> obj-$(CONFIG_FPGA) += fpga/
> diff --git a/drivers/hwtracing/Kconfig b/drivers/hwtracing/Kconfig
> index 13085835a636..911ee977103c 100644
> --- a/drivers/hwtracing/Kconfig
> +++ b/drivers/hwtracing/Kconfig
> @@ -5,4 +5,6 @@ source "drivers/hwtracing/stm/Kconfig"
>
> source "drivers/hwtracing/intel_th/Kconfig"
>
> +source "drivers/hwtracing/ptt/Kconfig"
> +
> endmenu
> diff --git a/drivers/hwtracing/ptt/Kconfig b/drivers/hwtracing/ptt/Kconfig
> new file mode 100644
> index 000000000000..8902a6f27563
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Kconfig
> @@ -0,0 +1,12 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config HISI_PTT
> + tristate "HiSilicon PCIe Tune and Trace Device"
> + depends on ARM64 || (COMPILE_TEST && 64BIT)
> + depends on PCI && HAS_DMA && HAS_IOMEM && PERF_EVENTS
> + help
> + HiSilicon PCIe Tune and Trace Device exists as a PCIe RCiEP
> + device, and it provides support for PCIe traffic tuning and
> + tracing TLP headers to the memory.
> +
> + This driver can also be built as a module. If so, the module
> + will be called hisi_ptt.
> diff --git a/drivers/hwtracing/ptt/Makefile b/drivers/hwtracing/ptt/Makefile
> new file mode 100644
> index 000000000000..908c09a98161
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_HISI_PTT) += hisi_ptt.o
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.c b/drivers/hwtracing/ptt/hisi_ptt.c
> new file mode 100644
> index 000000000000..242b41870380
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.c
> @@ -0,0 +1,874 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <yangyicong@...ilicon.com>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/delay.h>
> +#include <linux/dma-iommu.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/iommu.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/sysfs.h>
> +#include <linux/vmalloc.h>
> +
> +#include "hisi_ptt.h"
> +
> +static u16 hisi_ptt_get_filter_val(struct pci_dev *pdev)
> +{
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + return BIT(HISI_PCIE_CORE_PORT_ID(PCI_SLOT(pdev->devfn)));
> +
> + return PCI_DEVID(pdev->bus->number, pdev->devfn);
> +}
> +
> +static bool hisi_ptt_wait_trace_hw_idle(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_STS,
> + val, val & HISI_PTT_TRACE_IDLE,
> + HISI_PTT_WAIT_POLL_INTERVAL_US,
> + HISI_PTT_WAIT_TRACE_TIMEOUT_US);
> +}
> +
> +static bool hisi_ptt_wait_dma_reset_done(struct hisi_ptt *hisi_ptt)
> +{
> + u32 val;
> +
> + return !readl_poll_timeout_atomic(hisi_ptt->iobase + HISI_PTT_TRACE_WR_STS,
> + val, !val, HISI_PTT_RESET_POLL_INTERVAL_US,
> + HISI_PTT_RESET_TIMEOUT_US);
> +}
> +
> +static void hisi_ptt_free_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + if (!ctrl->trace_buf)
> + return;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + if (ctrl->trace_buf[i].addr)
> + dmam_free_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + ctrl->trace_buf[i].addr,
> + ctrl->trace_buf[i].dma);
> + }
> +
> + devm_kfree(dev, ctrl->trace_buf);
> + ctrl->trace_buf = NULL;
> +}
> +
> +static int hisi_ptt_alloc_trace_buf(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct device *dev = &hisi_ptt->pdev->dev;
> + int i;
> +
> + hisi_ptt->trace_ctrl.buf_index = 0;
> +
> + /* If the trace buffer has already been allocated, zero it. */
I am not sure why this is not called from the probe
> + if (ctrl->trace_buf) {
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++)
> + memset(ctrl->trace_buf[i].addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> + return 0;
> + }
> +
> + ctrl->trace_buf = devm_kcalloc(dev, HISI_PTT_TRACE_BUF_CNT,
> + sizeof(struct hisi_ptt_dma_buffer), GFP_KERNEL);
sizeof(*ctrl->trace_buf) may be better
> + if (!ctrl->trace_buf)
> + return -ENOMEM;
> +
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; ++i) {
> + ctrl->trace_buf[i].addr = dmam_alloc_coherent(dev, HISI_PTT_TRACE_BUF_SIZE,
> + &ctrl->trace_buf[i].dma,
> + GFP_KERNEL);
> + if (!ctrl->trace_buf[i].addr) {
> + hisi_ptt_free_trace_buf(hisi_ptt);
> + return -ENOMEM;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_trace_end(struct hisi_ptt *hisi_ptt)
> +{
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + hisi_ptt->trace_ctrl.started = false;
> +}
> +
> +static int hisi_ptt_trace_start(struct hisi_ptt *hisi_ptt)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + u32 val;
> + int i;
> +
> + /* Check device idle before start trace */
> + if (!hisi_ptt_wait_trace_hw_idle(hisi_ptt)) {
> + pci_err(hisi_ptt->pdev, "Failed to start trace, the device is still busy\n");
> + return -EBUSY;
> + }
> +
> + ctrl->started = true;
> +
> + /* Reset the DMA before start tracing */
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val |= HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + hisi_ptt_wait_dma_reset_done(hisi_ptt);
> +
> + val = readl(hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> + val &= ~HISI_PTT_TRACE_CTRL_RST;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + /* Clear the interrupt status */
> + writel(HISI_PTT_TRACE_INT_STAT_MASK, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + writel(0, hisi_ptt->iobase + HISI_PTT_TRACE_INT_MASK);
> +
> + /* Configure the trace DMA buffer */
I am not sure why this sort of thing is done outside probing
> + for (i = 0; i < HISI_PTT_TRACE_BUF_CNT; i++) {
> + writel(lower_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_LO_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + writel(upper_32_bits(ctrl->trace_buf[i].dma),
> + hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_BASE_HI_0 +
> + i * HISI_PTT_TRACE_ADDR_STRIDE);
> + }
> + writel(HISI_PTT_TRACE_BUF_SIZE, hisi_ptt->iobase + HISI_PTT_TRACE_ADDR_SIZE);
> +
> + /* Set the trace control register */
> + val = FIELD_PREP(HISI_PTT_TRACE_CTRL_TYPE_SEL, ctrl->type);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_RXTX_SEL, ctrl->direction);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_DATA_FORMAT, ctrl->format);
> + val |= FIELD_PREP(HISI_PTT_TRACE_CTRL_TARGET_SEL, hisi_ptt->trace_ctrl.filter);
> + if (!hisi_ptt->trace_ctrl.is_port)
> + val |= HISI_PTT_TRACE_CTRL_FILTER_MODE;
> +
> + /* Start the Trace */
> + val |= HISI_PTT_TRACE_CTRL_EN;
> + writel(val, hisi_ptt->iobase + HISI_PTT_TRACE_CTRL);
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_update_aux(struct hisi_ptt *hisi_ptt, int index, bool stop)
> +{
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + struct perf_output_handle *handle = &ctrl->handle;
> + struct perf_event *event = handle->event;
> + struct hisi_ptt_pmu_buf *buf;
> + void *addr;
> +
> + buf = perf_get_aux(handle);
> + if (!buf || !handle->size)
> + return -EINVAL;
> +
> + addr = ctrl->trace_buf[ctrl->buf_index].addr;
> +
> + memcpy(buf->base + buf->pos, addr, HISI_PTT_TRACE_BUF_SIZE);
> + memset(addr, 0, HISI_PTT_TRACE_BUF_SIZE);
> + buf->pos += HISI_PTT_TRACE_BUF_SIZE;
> +
> + if (stop) {
> + perf_aux_output_end(handle, buf->pos);
> + } else if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_skip(handle, buf->length - buf->pos);
> + perf_aux_output_end(handle, buf->pos);
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf)
> + return -EINVAL;
> +
> + buf->pos = handle->head % buf->length;
> + if (buf->length - buf->pos < HISI_PTT_TRACE_BUF_SIZE) {
> + perf_aux_output_end(handle, 0);
> + return -EINVAL;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static irqreturn_t hisi_ptt_isr(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status, buf_idx;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + buf_idx = ffs(status) - 1;
> +
> + /* Clear the interrupt status of buffer @buf_idx */
> + writel(status, hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> +
> + /*
> + * Update the AUX buffer and cache the current buffer index,
> + * as we need to know this and save the data when the trace
> + * is ended out of the interrupt handler. End the trace
> + * if the updating fails.
> + */
> + if (hisi_ptt_update_aux(hisi_ptt, buf_idx, false))
> + hisi_ptt_trace_end(hisi_ptt);
> + else
> + hisi_ptt->trace_ctrl.buf_index = (buf_idx + 1) % HISI_PTT_TRACE_BUF_CNT;
> +
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t hisi_ptt_irq(int irq, void *context)
> +{
> + struct hisi_ptt *hisi_ptt = context;
> + u32 status;
> +
> + status = readl(hisi_ptt->iobase + HISI_PTT_TRACE_INT_STAT);
> + if (!(status & HISI_PTT_TRACE_INT_STAT_MASK))
> + return IRQ_NONE;
> +
> + return IRQ_WAKE_THREAD;
> +}
> +
> +static void hisi_ptt_irq_free_vectors(void *pdev)
> +{
> + pci_free_irq_vectors(pdev);
> +}
> +
> +static int hisi_ptt_register_irq(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + int ret;
> +
> + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
> + if (ret < 0) {
> + pci_err(pdev, "failed to allocate irq vector, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_irq_free_vectors, pdev);
> + if (ret < 0)
> + return ret;
> +
> + ret = devm_request_threaded_irq(&pdev->dev,
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ),
> + hisi_ptt_irq, hisi_ptt_isr, 0,
> + DRV_NAME, hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to request irq %d, ret = %d\n",
> + pci_irq_vector(pdev, HISI_PTT_TRACE_DMA_IRQ), ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int hisi_ptt_init_filters(struct pci_dev *pdev, void *data)
> +{
> + struct hisi_ptt_filter_desc *filter;
> + struct hisi_ptt *hisi_ptt = data;
> + struct list_head *target_list;
> +
> + target_list = pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT ?
> + &hisi_ptt->port_filters : &hisi_ptt->req_filters;
> +
> + filter = kzalloc(sizeof(*filter), GFP_KERNEL);
> + if (!filter) {
> + pci_err(hisi_ptt->pdev, "failed to add filter %s\n", pci_name(pdev));
> + return -ENOMEM;
> + }
> +
> + filter->pdev = pdev;
> + list_add_tail(&filter->list, target_list);
> +
> + /* Update the available port mask */
> + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
> + hisi_ptt->port_mask |= hisi_ptt_get_filter_val(pdev);
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_release_filters(void *data)
> +{
> + struct hisi_ptt_filter_desc *filter, *tfilter;
> + struct hisi_ptt *hisi_ptt = data;
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->req_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +
> + list_for_each_entry_safe(filter, tfilter, &hisi_ptt->port_filters, list) {
> + list_del(&filter->list);
> + kfree(filter);
> + }
> +}
> +
> +static int hisi_ptt_init_ctrls(struct hisi_ptt *hisi_ptt)
> +{
> + struct pci_dev *pdev = hisi_ptt->pdev;
> + struct pci_bus *bus;
> + int ret;
> + u32 reg;
> +
> + INIT_LIST_HEAD(&hisi_ptt->port_filters);
> + INIT_LIST_HEAD(&hisi_ptt->req_filters);
> +
> + /*
> + * The device range register provides the information about the
> + * root ports which the RCiEP can control and trace. The RCiEP
> + * and the root ports it support are on the same PCIe core, with
> + * same domain number but maybe different bus number. The device
> + * range register will tell us which root ports we can support,
> + * Bit[31:16] indicates the upper BDF numbers of the root port,
> + * while Bit[15:0] indicates the lower.
> + */
> + reg = readl(hisi_ptt->iobase + HISI_PTT_DEVICE_RANGE);
> + hisi_ptt->upper = FIELD_GET(HISI_PTT_DEVICE_RANGE_UPPER, reg);
> + hisi_ptt->lower = FIELD_GET(HISI_PTT_DEVICE_RANGE_LOWER, reg);
> +
> + bus = pci_find_bus(pci_domain_nr(pdev->bus), PCI_BUS_NUM(hisi_ptt->upper));
> + if (bus)
> + pci_walk_bus(bus, hisi_ptt_init_filters, hisi_ptt);
> +
> + ret = devm_add_action_or_reset(&pdev->dev, hisi_ptt_release_filters, hisi_ptt);
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.default_cpu = cpumask_first(cpumask_of_node(dev_to_node(&pdev->dev)));
> +
> + return 0;
> +}
> +
> +#define HISI_PTT_PMU_FILTER_IS_PORT BIT(19)
> +#define HISI_PTT_PMU_FILTER_VAL_MASK GENMASK(15, 0)
> +#define HISI_PTT_PMU_DIRECTION_MASK GENMASK(23, 20)
> +#define HISI_PTT_PMU_TYPE_MASK GENMASK(31, 24)
> +#define HISI_PTT_PMU_FORMAT_MASK GENMASK(35, 32)
> +
> +static ssize_t available_root_port_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->port_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->port_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05lx\n",
\t can be used for a formatting tab
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev) |
> + HISI_PTT_PMU_FILTER_IS_PORT);
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_root_port_filters);
> +
> +static ssize_t available_requester_filters_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(dev_get_drvdata(dev));
> + struct hisi_ptt_filter_desc *filter;
> + int pos = 0;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (list_empty(&hisi_ptt->req_filters)) {
> + pos = sysfs_emit(buf, "\n");
> + goto out;
> + }
> +
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
> + pos += sysfs_emit_at(buf, pos, "%s 0x%05x\n",
> + pci_name(filter->pdev),
> + hisi_ptt_get_filter_val(filter->pdev));
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return pos;
> +}
> +static DEVICE_ATTR_ADMIN_RO(available_requester_filters);
> +
> +PMU_FORMAT_ATTR(filter, "config:0-19");
> +PMU_FORMAT_ATTR(direction, "config:20-23");
> +PMU_FORMAT_ATTR(type, "config:24-31");
> +PMU_FORMAT_ATTR(format, "config:32-35");
> +
> +static struct attribute *hisi_ptt_pmu_format_attrs[] = {
> + &format_attr_filter.attr,
> + &format_attr_direction.attr,
> + &format_attr_type.attr,
> + &format_attr_format.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_format_group = {
> + .name = "format",
> + .attrs = hisi_ptt_pmu_format_attrs,
> +};
> +
> +static struct attribute *hisi_ptt_pmu_filter_attrs[] = {
> + &dev_attr_available_root_port_filters.attr,
> + &dev_attr_available_requester_filters.attr,
> + NULL
> +};
> +
> +static struct attribute_group hisi_ptt_pmu_filter_group = {
> + .attrs = hisi_ptt_pmu_filter_attrs,
> +};
> +
> +static const struct attribute_group *hisi_ptt_pmu_groups[] = {
> + &hisi_ptt_pmu_format_group,
> + &hisi_ptt_pmu_filter_group,
> + NULL
> +};
> +
> +/*
> + * Check whether the config is valid or not. Some configs are multi-selectable
> + * and can be set simultaneously, while some are single selectable (onehot).
> + * Use this function to check the non-onehot configs while
> + * hisi_ptt_trace_valid_config_onehot() for the onehot ones.
> + */
> +static int hisi_ptt_trace_valid_config(u32 val, const u32 *available_list, u32 list_size)
> +{
> + int i;
> +
> + /* The non-onehot configs cannot be 0. */
> + if (!val)
> + return -EINVAL;
> +
> + /*
> + * Walk the available list and clear the valid bits of
> + * the config. If there is any resident bit after the
> + * walk then the config is invalid.
> + */
> + for (i = 0; i < list_size; i++)
> + val &= ~available_list[i];
> +
> + return val ? -EINVAL : 0;
> +}
> +
> +static int hisi_ptt_trace_valid_config_onehot(u32 val, const u32 *available_list, u32 list_size)
line too long
> +{
> + int i;
> +
> + for (i = 0; i < list_size; i++)
> + if (val == available_list[i])
> + return 0;
> +
> + return -EINVAL;
> +}
> +
> +static int hisi_ptt_trace_init_filter(struct hisi_ptt *hisi_ptt, u64 config)
> +{
> + unsigned long val, port_mask = hisi_ptt->port_mask;
> + struct hisi_ptt_filter_desc *filter;
> + int ret = -EINVAL;
> +
> + hisi_ptt->trace_ctrl.is_port = FIELD_GET(HISI_PTT_PMU_FILTER_IS_PORT, config);
> + val = FIELD_GET(HISI_PTT_PMU_FILTER_VAL_MASK, config);
> +
> + /*
> + * Port filters are defined as bit mask. For port filters, check
> + * the bits in the @val are within the range of hisi_ptt->port_mask
> + * and whether it's empty or not, otherwise user has specified
> + * some unsupported root ports.
> + *
> + * For Requester ID filters, walk the available filter list to see
> + * whether we have one matched.
> + */
> + if (!hisi_ptt->trace_ctrl.is_port) {
> + list_for_each_entry(filter, &hisi_ptt->req_filters, list)
use {} for this as well. the formatting looks strange
> + if (val == hisi_ptt_get_filter_val(filter->pdev)) {
> + ret = 0;
> + break;
> + }
> + } else if (bitmap_subset(&val, &port_mask, BITS_PER_LONG)) {
> + ret = 0;
> + }
> +
> + if (ret)
> + return ret;
> +
> + hisi_ptt->trace_ctrl.filter = val;
> + return 0;
> +}
> +
> +static int hisi_ptt_pmu_event_init(struct perf_event *event)
> +{
> + /*
> + * The supported value of the direction parameter. See hisi_ptt.rst
> + * documentation for more details.
> + */
> + static const u32 hisi_ptt_trace_available_direction[] = {
> + 0,
> + 1,
> + 2,
> + 3,
> + };
> + /* Different types can be set simultaneously */
> + static const u32 hisi_ptt_trace_available_type[] = {
> + 1, /* posted_request */
> + 2, /* non-posted_request */
> + 4, /* completion */
> + };
> + static const u32 hisi_ptt_trace_availble_format[] = {
> + 0, /* 4DW */
> + 1, /* 8DW */
> + };
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hisi_ptt_trace_ctrl *ctrl = &hisi_ptt->trace_ctrl;
> + int ret;
> + u32 val;
> +
> + if (event->attr.type != hisi_ptt->hisi_ptt_pmu.type)
> + return -ENOENT;
> +
> + mutex_lock(&hisi_ptt->mutex);
> +
> + ret = hisi_ptt_trace_init_filter(hisi_ptt, event->attr.config);
> + if (ret < 0)
> + goto out;
> +
> + val = FIELD_GET(HISI_PTT_PMU_DIRECTION_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_available_direction,
how about put all those arrays in hisi_ptt_trace_valid_config_onehot()
and pass some flag to say which array you want to use? Or something like
that. Passing the arrays in this fashion is messy
> + ARRAY_SIZE(hisi_ptt_trace_available_direction));
> + if (ret < 0)
> + goto out;
> + ctrl->direction = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_TYPE_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config(val, hisi_ptt_trace_available_type,
> + ARRAY_SIZE(hisi_ptt_trace_available_type));
> + if (ret < 0)
> + goto out;
> + ctrl->type = val;
> +
> + val = FIELD_GET(HISI_PTT_PMU_FORMAT_MASK, event->attr.config);
> + ret = hisi_ptt_trace_valid_config_onehot(val, hisi_ptt_trace_availble_format,
> + ARRAY_SIZE(hisi_ptt_trace_availble_format));
> + if (ret < 0)
> + goto out;
> + ctrl->format = val;
> +
> +out:
> + mutex_unlock(&hisi_ptt->mutex);
> + return ret;
> +}
> +
> +static void *hisi_ptt_pmu_setup_aux(struct perf_event *event, void **pages,
> + int nr_pages, bool overwrite)
> +{
> + struct hisi_ptt_pmu_buf *buf;
> + struct page **pagelist;
> + int i;
> +
> + if (overwrite) {
> + dev_warn(event->pmu->dev, "Overwrite mode is not supported\n");
> + return NULL;
> + }
> +
> + /* If the pages size less than buffers, we cannot start trace */
> + if (nr_pages < HISI_PTT_TRACE_TOTAL_BUF_SIZE / PAGE_SIZE)
> + return NULL;
> +
> + buf = kzalloc(sizeof(*buf), GFP_KERNEL);
> + if (!buf)
> + return NULL;
> +
> + pagelist = kcalloc(nr_pages, sizeof(*pagelist), GFP_KERNEL);
> + if (!pagelist) {
> + kfree(buf);
> + return NULL;
> + }
> +
> + for (i = 0; i < nr_pages; i++)
> + pagelist[i] = virt_to_page(pages[i]);
> +
> + buf->base = vmap(pagelist, nr_pages, VM_MAP, PAGE_KERNEL);
> + if (!buf->base) {
> + kfree(pagelist);
> + kfree(buf);
> + return NULL;
> + }
> +
> + buf->nr_pages = nr_pages;
> + buf->length = nr_pages * PAGE_SIZE;
> + buf->pos = 0;
> +
> + kfree(pagelist);
> + return buf;
> +}
> +
> +static void hisi_ptt_pmu_free_aux(void *aux)
> +{
> + struct hisi_ptt_pmu_buf *buf = aux;
> +
> + vunmap(buf->base);
> + kfree(buf);
> +}
> +
> +static void hisi_ptt_pmu_start(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct perf_output_handle *handle = &hisi_ptt->trace_ctrl.handle;
> + struct hw_perf_event *hwc = &event->hw;
> + struct hisi_ptt_pmu_buf *buf;
> + int cpu = event->cpu;
> + int ret;
> +
> + hwc->state = 0;
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + pci_dbg(hisi_ptt->pdev, "trace has already started\n");
doesn't perf core guard against this sort of thing?
> + goto stop;
> + }
> +
> + if (cpu == -1)
> + cpu = hisi_ptt->trace_ctrl.default_cpu;
> +
> + /*
> + * Handle the interrupt on the same cpu which starts the trace to avoid
> + * context mismatch. Otherwise we'll trigger the WARN from the perf
> + * core in event_function_local().
> + */
> + WARN_ON(irq_set_affinity(pci_irq_vector(hisi_ptt->pdev, HISI_PTT_TRACE_DMA_IRQ),
> + cpumask_of(cpu)));
> +
> + ret = hisi_ptt_alloc_trace_buf(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "alloc trace buf failed, ret = %d\n", ret);
> + goto stop;
> + }
> +
> + buf = perf_aux_output_begin(handle, event);
> + if (!buf) {
> + pci_dbg(hisi_ptt->pdev, "aux output begin failed\n");
> + goto stop;
> + }
> +
> + buf->pos = handle->head % buf->length;
> +
> + ret = hisi_ptt_trace_start(hisi_ptt);
> + if (ret) {
> + pci_dbg(hisi_ptt->pdev, "trace start failed, ret = %d\n", ret);
> + perf_aux_output_end(handle, 0);
> + goto stop;
> + }
> +
> + mutex_unlock(&hisi_ptt->mutex);
> + return;
> +stop:
> + event->hw.state |= PERF_HES_STOPPED;
> + mutex_unlock(&hisi_ptt->mutex);
> +}
> +
> +static void hisi_ptt_pmu_stop(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> +
> + if (hwc->state & PERF_HES_STOPPED)
> + return;
> +
> + mutex_lock(&hisi_ptt->mutex);
> + if (hisi_ptt->trace_ctrl.started) {
> + hisi_ptt_trace_end(hisi_ptt);
> + WARN(!hisi_ptt_wait_trace_hw_idle(hisi_ptt), "Device is still busy");
> + hisi_ptt_update_aux(hisi_ptt, hisi_ptt->trace_ctrl.buf_index, true);
> + }
> + mutex_unlock(&hisi_ptt->mutex);
> +
> + hwc->state |= PERF_HES_STOPPED;
> + perf_event_update_userpage(event);
> + hwc->state |= PERF_HES_UPTODATE;
> +}
> +
> +static int hisi_ptt_pmu_add(struct perf_event *event, int flags)
> +{
> + struct hisi_ptt *hisi_ptt = to_hisi_ptt(event->pmu);
> + struct hw_perf_event *hwc = &event->hw;
> + int cpu = event->cpu;
> +
> + /*
> + * Only allow the default cpu to add the event if user doesn't specify
> + * the cpus.
> + */
> + if (cpu == -1 && smp_processor_id() != hisi_ptt->trace_ctrl.default_cpu)
> + return 0;
> +
> + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
> +
> + if (flags & PERF_EF_START) {
> + hisi_ptt_pmu_start(event, PERF_EF_RELOAD);
> + if (hwc->state & PERF_HES_STOPPED)
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_pmu_del(struct perf_event *event, int flags)
> +{
> + hisi_ptt_pmu_stop(event, PERF_EF_UPDATE);
> +}
> +
> +static int hisi_ptt_register_pmu(struct hisi_ptt *hisi_ptt)
> +{
> + u16 core_id, sicl_id;
> + char *pmu_name;
> + u32 reg;
> +
> + hisi_ptt->hisi_ptt_pmu = (struct pmu) {
> + .module = THIS_MODULE,
> + .capabilities = PERF_PMU_CAP_EXCLUSIVE | PERF_PMU_CAP_ITRACE,
> + .task_ctx_nr = perf_sw_context,
> + .attr_groups = hisi_ptt_pmu_groups,
> + .event_init = hisi_ptt_pmu_event_init,
> + .setup_aux = hisi_ptt_pmu_setup_aux,
> + .free_aux = hisi_ptt_pmu_free_aux,
> + .start = hisi_ptt_pmu_start,
> + .stop = hisi_ptt_pmu_stop,
> + .add = hisi_ptt_pmu_add,
> + .del = hisi_ptt_pmu_del,
> + };
> +
> + reg = readl(hisi_ptt->iobase + HISI_PTT_LOCATION);
> + core_id = FIELD_GET(HISI_PTT_CORE_ID, reg);
> + sicl_id = FIELD_GET(HISI_PTT_SICL_ID, reg);
> +
> + pmu_name = devm_kasprintf(&hisi_ptt->pdev->dev, GFP_KERNEL, "hisi_ptt%u_%u",
> + sicl_id, core_id);
> + if (!pmu_name)
> + return -ENOMEM;
> +
> + return perf_pmu_register(&hisi_ptt->hisi_ptt_pmu, pmu_name, -1);
> +}
> +
> +/*
> + * The DMA of PTT trace can only use direct mapping, due to some
> + * hardware restriction. Check whether there is an IOMMU or the
> + * policy of the IOMMU domain is passthrough, otherwise the trace
> + * cannot work.
> + *
> + * The PTT device is supposed to behind the ARM SMMUv3, which
/s/ the ARM SMMUv3/an ARM SMMUv3/
> + * should have passthrough the device by a quirk.
> + */
> +static int hisi_ptt_check_iommu_mapping(struct pci_dev *pdev)
> +{
> + struct iommu_domain *iommu_domain;
> +
> + iommu_domain = iommu_get_domain_for_dev(&pdev->dev);
> + if (!iommu_domain || iommu_domain->type == IOMMU_DOMAIN_IDENTITY)
> + return 0;
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int hisi_ptt_probe(struct pci_dev *pdev,
> + const struct pci_device_id *id)
> +{
> + struct hisi_ptt *hisi_ptt;
> + int ret;
> +
> + ret = hisi_ptt_check_iommu_mapping(pdev);
> + if (ret) {
> + pci_err(pdev, "requires direct DMA mappings\n");
> + return ret;
> + }
> +
> + hisi_ptt = devm_kzalloc(&pdev->dev, sizeof(*hisi_ptt), GFP_KERNEL);
> + if (!hisi_ptt)
> + return -ENOMEM;
> +
> + mutex_init(&hisi_ptt->mutex);
> + hisi_ptt->pdev = pdev;
> + pci_set_drvdata(pdev, hisi_ptt);
> +
> + ret = pcim_enable_device(pdev);
> + if (ret) {
> + pci_err(pdev, "failed to enable device, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = pcim_iomap_regions(pdev, BIT(2), DRV_NAME);
> + if (ret) {
> + pci_err(pdev, "failed to remap io memory, ret = %d\n", ret);
> + return ret;
> + }
> +
> + hisi_ptt->iobase = pcim_iomap_table(pdev)[2];
> +
> + ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64));
> + if (ret) {
> + pci_err(pdev, "failed to set 64 bit dma mask, ret = %d\n", ret);
> + return ret;
> + }
> +
> + pci_set_master(pdev);
> +
> + ret = hisi_ptt_register_irq(hisi_ptt);
> + if (ret)
> + return ret;
> +
> + ret = hisi_ptt_init_ctrls(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to init controls, ret = %d\n", ret);
> + return ret;
> + }
> +
> + ret = hisi_ptt_register_pmu(hisi_ptt);
> + if (ret) {
> + pci_err(pdev, "failed to register PMU device, ret = %d", ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void hisi_ptt_remove(struct pci_dev *pdev)
> +{
> + struct hisi_ptt *hisi_ptt = pci_get_drvdata(pdev);
> +
> + /*
> + * We have to manually unregister the PMU device rather than make it
> + * devres managed to keep order that the PMU device's unregistration
> + * is prior to the release of DMA buffers. As the DMA buffers are
> + * devm allocated when necessary which is after the registration of
> + * the PMU device.
> + */
do you really need to mention all this?
> + perf_pmu_unregister(&hisi_ptt->hisi_ptt_pmu);
> +}
> +
> +static const struct pci_device_id hisi_ptt_id_tbl[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12e) },
> + { }
> +};
> +MODULE_DEVICE_TABLE(pci, hisi_ptt_id_tbl);
> +
> +static struct pci_driver hisi_ptt_driver = {
> + .name = DRV_NAME,
> + .id_table = hisi_ptt_id_tbl,
> + .probe = hisi_ptt_probe,
> + .remove = hisi_ptt_remove,
> +};
> +module_pci_driver(hisi_ptt_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("Yicong Yang <yangyicong@...ilicon.com>");
> +MODULE_DESCRIPTION("Driver for HiSilicon PCIe tune and trace device");
> diff --git a/drivers/hwtracing/ptt/hisi_ptt.h b/drivers/hwtracing/ptt/hisi_ptt.h
> new file mode 100644
> index 000000000000..29b6d6293d6c
> --- /dev/null
> +++ b/drivers/hwtracing/ptt/hisi_ptt.h
> @@ -0,0 +1,166 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Driver for HiSilicon PCIe tune and trace device
> + *
> + * Copyright (c) 2022 HiSilicon Technologies Co., Ltd.
> + * Author: Yicong Yang <yangyicong@...ilicon.com>
> + */
> +
> +#ifndef _HISI_PTT_H
> +#define _HISI_PTT_H
> +
> +#include <linux/bits.h>
> +#include <linux/list.h>
> +#include <linux/mutex.h>
> +#include <linux/pci.h>
> +#include <linux/perf_event.h>
> +#include <linux/types.h>
> +
> +#define DRV_NAME "hisi_ptt"
> +
> +/*
> + * The definition of the device registers and register fields.
> + */
> +#define HISI_PTT_TRACE_ADDR_SIZE 0x0800
> +#define HISI_PTT_TRACE_ADDR_BASE_LO_0 0x0810
> +#define HISI_PTT_TRACE_ADDR_BASE_HI_0 0x0814
> +#define HISI_PTT_TRACE_ADDR_STRIDE 0x8
> +#define HISI_PTT_TRACE_CTRL 0x0850
> +#define HISI_PTT_TRACE_CTRL_EN BIT(0)
> +#define HISI_PTT_TRACE_CTRL_RST BIT(1)
> +#define HISI_PTT_TRACE_CTRL_RXTX_SEL GENMASK(3, 2)
> +#define HISI_PTT_TRACE_CTRL_TYPE_SEL GENMASK(7, 4)
> +#define HISI_PTT_TRACE_CTRL_DATA_FORMAT BIT(14)
> +#define HISI_PTT_TRACE_CTRL_FILTER_MODE BIT(15)
> +#define HISI_PTT_TRACE_CTRL_TARGET_SEL GENMASK(31, 16)
> +#define HISI_PTT_TRACE_INT_STAT 0x0890
> +#define HISI_PTT_TRACE_INT_STAT_MASK GENMASK(3, 0)
> +#define HISI_PTT_TRACE_INT_MASK 0x0894
> +#define HISI_PTT_TRACE_WR_STS 0x08a0
> +#define HISI_PTT_TRACE_WR_STS_WRITE GENMASK(27, 0)
> +#define HISI_PTT_TRACE_WR_STS_BUFFER GENMASK(29, 28)
> +#define HISI_PTT_TRACE_STS 0x08b0
> +#define HISI_PTT_TRACE_IDLE BIT(0)
> +#define HISI_PTT_DEVICE_RANGE 0x0fe0
> +#define HISI_PTT_DEVICE_RANGE_UPPER GENMASK(31, 16)
> +#define HISI_PTT_DEVICE_RANGE_LOWER GENMASK(15, 0)
> +#define HISI_PTT_LOCATION 0x0fe8
> +#define HISI_PTT_CORE_ID GENMASK(15, 0)
> +#define HISI_PTT_SICL_ID GENMASK(31, 16)
> +
> +/* Parameters of PTT trace DMA part. */
> +#define HISI_PTT_TRACE_DMA_IRQ 0
> +#define HISI_PTT_TRACE_BUF_CNT 4
> +#define HISI_PTT_TRACE_BUF_SIZE SZ_4M
> +#define HISI_PTT_TRACE_TOTAL_BUF_SIZE (HISI_PTT_TRACE_BUF_SIZE * \
> + HISI_PTT_TRACE_BUF_CNT)
> +/* Wait time for hardware DMA to reset */
> +#define HISI_PTT_RESET_TIMEOUT_US 10UL
> +#define HISI_PTT_RESET_POLL_INTERVAL_US 1UL
> +/* Poll timeout and interval for waiting hardware work to finish */
> +#define HISI_PTT_WAIT_TRACE_TIMEOUT_US 100UL
> +#define HISI_PTT_WAIT_POLL_INTERVAL_US 10UL
> +
> +#define HISI_PCIE_CORE_PORT_ID(devfn) (PCI_FUNC(devfn) << 1)
> +
> +/**
> + * struct hisi_ptt_dma_buffer - describe a single trace buffer of PTT trace.
> + * The detail of the data format is described
> + * in the documentation of PTT device.
> + * @dma: DMA address of this buffer visible to the device
> + * @addr: virtual address of this buffer visible to the cpu
> + */
> +struct hisi_ptt_dma_buffer {
> + dma_addr_t dma;
> + void *addr;
> +};
> +
> +/**
> + * struct hisi_ptt_trace_ctrl - control and status of PTT trace
> + * @trace_buf: array of the trace buffers for holding the trace data.
> + * the length will be HISI_PTT_TRACE_BUF_CNT.
> + * @handle: perf output handle of current trace session
> + * @default_cpu: default cpu to start the trace session
> + * @buf_index: the index of current using trace buffer
> + * @started: current trace status, true for started
> + * @is_port: whether we're tracing root port or not
> + * @direction: direction of the TLP headers to trace
> + * @filter: filter value for tracing the TLP headers
> + * @format: format of the TLP headers to trace
> + * @type: type of the TLP headers to trace
> + */
> +struct hisi_ptt_trace_ctrl {
> + struct hisi_ptt_dma_buffer *trace_buf;
> + struct perf_output_handle handle;
> + int default_cpu;
> + u32 buf_index;
> + bool started;
> + bool is_port;
> + u32 direction:2;
> + u32 filter:16;
> + u32 format:1;
> + u32 type:4;
> +};
> +
> +/**
> + * struct hisi_ptt_filter_desc - descriptor of the PTT trace filter
> + * @list: entry of this descriptor in the filter list
> + * @pdev: pci_dev related to this filter
> + */
> +struct hisi_ptt_filter_desc {
> + struct list_head list;
> + struct pci_dev *pdev;
> +};
> +
> +
> +/**
> + * struct hisi_ptt_pmu_buf - descriptor of the AUX buffer of PTT trace
> + * @length: size of the AUX buffer
> + * @nr_pages: number of pages of the AUX buffer
> + * @base: start address of AUX buffer
> + * @pos: position in the AUX buffer to commit traced data
> + */
> +struct hisi_ptt_pmu_buf {
> + size_t length;
> + int nr_pages;
> + void *base;
> + long pos;
> +};
> +
> +/**
> + * struct hisi_ptt - per PTT device data
> + * @trace_ctrl: the control information of PTT trace
> + * @hisi_ptt_pmu: the pum device of trace
> + * @iobase: base IO address of the device
> + * @pdev: pci_dev of this PTT device
> + * @mutex: mutex to protect the filter list and serialize the perf process.
> + * @upper: the upper BDF range of the PCI devices managed by this PTT device
> + * @lower: the lower BDF range of the PCI devices managed by this PTT device
> + * @port_filters: the filter list of root ports
> + * @req_filters: the filter list of requester ID
> + * @port_mask: port mask of the managed root ports
> + */
> +struct hisi_ptt {
> + struct hisi_ptt_trace_ctrl trace_ctrl;
> + struct pmu hisi_ptt_pmu;
> + void __iomem *iobase;
> + struct pci_dev *pdev;
> + struct mutex mutex;
> + u32 upper;
upper_bdf would be a better name
people don't want to always refer to comments to check the meaning
> + u32 lower;
> +
> + /*
> + * The trace TLP headers can either be filtered by certain
> + * root port, or by the requester ID. Organize the filters
> + * by @port_filters and @req_filters here. The mask of all
> + * the valid ports is also cached for doing sanity check
> + * of user input.
> + */
> + struct list_head port_filters;
> + struct list_head req_filters;
> + u16 port_mask;
> +};
> +
> +#define to_hisi_ptt(pmu) container_of(pmu, struct hisi_ptt, hisi_ptt_pmu)
> +
> +#endif /* _HISI_PTT_H */
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