+ 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..935dc9b44a54 --- /dev/null +++ b/drivers/hwtracing/ptt/hisi_ptt.c @@ -0,0 +1,330 @@ +// 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@xxxxxxxxxxxxx> + */ + +#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 "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)
no caller
+{ + 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. */ + 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); + 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)
again this function has no caller, so I assume a warn is generated if we only apply up to this patch (when compiling)
please only add code per-patch which is actually referenced
+{ + 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");
Are we already going to have a "device busy" message? I just wonder if we need this at all
+ 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 */ + 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_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) + 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); + + /* + * hisi_ptt_init_filters() only fails when the memory allocation failed. + * We don't check the failure here as it won't fail after adding the + * support of dynamically updating the filters in the following patch.
please structure the series such that we don't need to talk about how we will fix it later
+ */ + 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; +} + +/* + * 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 + * 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, "cannot work with non-direct DMA mapping.\n");
please no double-negatives like this, so maybe "requires direct DMA mappings"
+ 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);
nit: no '.' at end of any messages
+ 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);
I do doubt that this message is any use
+ return ret; + } + + pci_set_master(pdev); + + ret = hisi_ptt_init_ctrls(hisi_ptt); + if (ret) { + pci_err(pdev, "failed to init controls, ret = %d.\n", ret); + return ret; + } + + return 0; +} +