Re: [PATCH V5 XRT Alveo 09/20] fpga: xrt: management physical function driver (root)

Tom Rix
2021-05-03T13:49:59Z

On 4/27/21 1:54 PM, Lizhi Hou wrote:
> The PCIE device driver which attaches to management function on Alveo
> devices. It instantiates one or more group drivers which, in turn,
> instantiate xrt drivers. The instantiation of group and xrt drivers is
> completely dtb driven.
>
> Signed-off-by: Sonal Santan <sonal.santan@xilinx.com>
> Signed-off-by: Max Zhen <max.zhen@xilinx.com>
> Signed-off-by: Lizhi Hou <lizhi.hou@xilinx.com>
Reviewed-by: Tom Rix <trix@redhat.com>
> ---
> drivers/fpga/xrt/mgnt/root.c | 419 +++++++++++++++++++++++++++++++++++
> 1 file changed, 419 insertions(+)
> create mode 100644 drivers/fpga/xrt/mgnt/root.c
>
> diff --git a/drivers/fpga/xrt/mgnt/root.c b/drivers/fpga/xrt/mgnt/root.c
> new file mode 100644
> index 000000000000..6e362e9d4b59
> --- /dev/null
> +++ b/drivers/fpga/xrt/mgnt/root.c
> @@ -0,0 +1,419 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Xilinx Alveo Management Function Driver
> + *
> + * Copyright (C) 2020-2021 Xilinx, Inc.
> + *
> + * Authors:
> + * Cheng Zhen <maxz@xilinx.com>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/aer.h>
> +#include <linux/vmalloc.h>
> +#include <linux/delay.h>
> +
> +#include "xroot.h"
> +#include "xmgnt.h"
> +#include "metadata.h"
> +
> +#define XMGNT_MODULE_NAME "xrt-mgnt"
> +#define XMGNT_DRIVER_VERSION "4.0.0"
> +
> +#define XMGNT_PDEV(xm) ((xm)->pdev)
> +#define XMGNT_DEV(xm) (&(XMGNT_PDEV(xm)->dev))
> +#define xmgnt_err(xm, fmt, args...) \
> + dev_err(XMGNT_DEV(xm), "%s: " fmt, __func__, ##args)
> +#define xmgnt_warn(xm, fmt, args...) \
> + dev_warn(XMGNT_DEV(xm), "%s: " fmt, __func__, ##args)
> +#define xmgnt_info(xm, fmt, args...) \
> + dev_info(XMGNT_DEV(xm), "%s: " fmt, __func__, ##args)
> +#define xmgnt_dbg(xm, fmt, args...) \
> + dev_dbg(XMGNT_DEV(xm), "%s: " fmt, __func__, ##args)
> +#define XMGNT_DEV_ID(_pcidev) \
> + ({ typeof(_pcidev) (pcidev) = (_pcidev); \
> + ((pci_domain_nr((pcidev)->bus) << 16) | \
> + PCI_DEVID((pcidev)->bus->number, 0)); })
> +#define XRT_VSEC_ID 0x20
> +#define XRT_MAX_READRQ 512
> +
> +static struct class *xmgnt_class;
> +
> +/* PCI Device IDs */
> +/*
> + * Golden image is preloaded on the device when it is shipped to customer.
> + * Then, customer can load other shells (from Xilinx or some other vendor).
> + * If something goes wrong with the shell, customer can always go back to
> + * golden and start over again.
> + */
> +#define PCI_DEVICE_ID_U50_GOLDEN 0xD020
> +#define PCI_DEVICE_ID_U50 0x5020
> +static const struct pci_device_id xmgnt_pci_ids[] = {
> + { PCI_DEVICE(PCI_VENDOR_ID_XILINX, PCI_DEVICE_ID_U50_GOLDEN), }, /* Alveo U50 (golden) */
> + { PCI_DEVICE(PCI_VENDOR_ID_XILINX, PCI_DEVICE_ID_U50), }, /* Alveo U50 */
> + { 0, }
> +};
> +
> +struct xmgnt {
> + struct pci_dev *pdev;
> + void *root;
> +
> + bool ready;
> +};
> +
> +static int xmgnt_config_pci(struct xmgnt *xm)
> +{
> + struct pci_dev *pdev = XMGNT_PDEV(xm);
> + int rc;
> +
> + rc = pcim_enable_device(pdev);
> + if (rc < 0) {
> + xmgnt_err(xm, "failed to enable device: %d", rc);
> + return rc;
> + }
> +
> + rc = pci_enable_pcie_error_reporting(pdev);
> + if (rc)
> + xmgnt_warn(xm, "failed to enable AER: %d", rc);
> +
> + pci_set_master(pdev);
> +
> + rc = pcie_get_readrq(pdev);
> + if (rc > XRT_MAX_READRQ)
> + pcie_set_readrq(pdev, XRT_MAX_READRQ);
> + return 0;
> +}
> +
> +static int xmgnt_match_slot_and_save(struct device *dev, void *data)
> +{
> + struct xmgnt *xm = data;
> + struct pci_dev *pdev = to_pci_dev(dev);
> +
> + if (XMGNT_DEV_ID(pdev) == XMGNT_DEV_ID(xm->pdev)) {
> + pci_cfg_access_lock(pdev);
> + pci_save_state(pdev);
> + }
> +
> + return 0;
> +}
> +
> +static void xmgnt_pci_save_config_all(struct xmgnt *xm)
> +{
> + bus_for_each_dev(&pci_bus_type, NULL, xm, xmgnt_match_slot_and_save);
> +}
> +
> +static int xmgnt_match_slot_and_restore(struct device *dev, void *data)
> +{
> + struct xmgnt *xm = data;
> + struct pci_dev *pdev = to_pci_dev(dev);
> +
> + if (XMGNT_DEV_ID(pdev) == XMGNT_DEV_ID(xm->pdev)) {
> + pci_restore_state(pdev);
> + pci_cfg_access_unlock(pdev);
> + }
> +
> + return 0;
> +}
> +
> +static void xmgnt_pci_restore_config_all(struct xmgnt *xm)
> +{
> + bus_for_each_dev(&pci_bus_type, NULL, xm, xmgnt_match_slot_and_restore);
> +}
> +
> +static void xmgnt_root_hot_reset(struct device *dev)
> +{
> + struct pci_dev *pdev = to_pci_dev(dev);
> + struct pci_bus *bus;
> + u16 pci_cmd, devctl;
> + struct xmgnt *xm;
> + u8 pci_bctl;
> + int i, ret;
> +
> + xm = pci_get_drvdata(pdev);
> + xmgnt_info(xm, "hot reset start");
> + xmgnt_pci_save_config_all(xm);
> + pci_disable_device(pdev);
> + bus = pdev->bus;
> +
> + /*
> + * When flipping the SBR bit, device can fall off the bus. This is
> + * usually no problem at all so long as drivers are working properly
> + * after SBR. However, some systems complain bitterly when the device
> + * falls off the bus.
> + * The quick solution is to temporarily disable the SERR reporting of
> + * switch port during SBR.
> + */
> +
> + pci_read_config_word(bus->self, PCI_COMMAND, &pci_cmd);
> + pci_write_config_word(bus->self, PCI_COMMAND, (pci_cmd & ~PCI_COMMAND_SERR));
> + pcie_capability_read_word(bus->self, PCI_EXP_DEVCTL, &devctl);
> + pcie_capability_write_word(bus->self, PCI_EXP_DEVCTL, (devctl & ~PCI_EXP_DEVCTL_FERE));
> + pci_read_config_byte(bus->self, PCI_BRIDGE_CONTROL, &pci_bctl);
> + pci_write_config_byte(bus->self, PCI_BRIDGE_CONTROL, pci_bctl | PCI_BRIDGE_CTL_BUS_RESET);
> + msleep(100);
> + pci_write_config_byte(bus->self, PCI_BRIDGE_CONTROL, pci_bctl);
> + ssleep(1);
> +
> + pcie_capability_write_word(bus->self, PCI_EXP_DEVCTL, devctl);
> + pci_write_config_word(bus->self, PCI_COMMAND, pci_cmd);
> +
> + ret = pci_enable_device(pdev);
> + if (ret)
> + xmgnt_err(xm, "failed to enable device, ret %d", ret);
> +
> + for (i = 0; i < 300; i++) {
> + pci_read_config_word(pdev, PCI_COMMAND, &pci_cmd);
> + if (pci_cmd != 0xffff)
> + break;
> + msleep(20);
> + }
> + if (i == 300)
> + xmgnt_err(xm, "timed out waiting for device to be online after reset");
> +
> + xmgnt_info(xm, "waiting for %d ms", i * 20);
> + xmgnt_pci_restore_config_all(xm);
> + xmgnt_config_pci(xm);
> +}
> +
> +static int xmgnt_add_vsec_node(struct xmgnt *xm, char *dtb)
> +{
> + u32 off_low, off_high, vsec_bar, header;
> + struct pci_dev *pdev = XMGNT_PDEV(xm);
> + struct xrt_md_endpoint ep = { 0 };
> + struct device *dev = DEV(pdev);
> + int cap = 0, ret = 0;
> + u64 vsec_off;
> +
> + while ((cap = pci_find_next_ext_capability(pdev, cap, PCI_EXT_CAP_ID_VNDR))) {
> + pci_read_config_dword(pdev, cap + PCI_VNDR_HEADER, &header);
> + if (PCI_VNDR_HEADER_ID(header) == XRT_VSEC_ID)
> + break;
> + }
> + if (!cap) {
> + xmgnt_info(xm, "No Vendor Specific Capability.");
> + return -ENOENT;
> + }
> +
> + if (pci_read_config_dword(pdev, cap + 8, &off_low) ||
> + pci_read_config_dword(pdev, cap + 12, &off_high)) {
> + xmgnt_err(xm, "pci_read vendor specific failed.");
> + return -EINVAL;
> + }
> +
> + ep.ep_name = XRT_MD_NODE_VSEC;
> + ret = xrt_md_add_endpoint(dev, dtb, &ep);
> + if (ret) {
> + xmgnt_err(xm, "add vsec metadata failed, ret %d", ret);
> + goto failed;
> + }
> +
> + vsec_bar = cpu_to_be32(off_low & 0xf);
> + ret = xrt_md_set_prop(dev, dtb, XRT_MD_NODE_VSEC, NULL,
> + XRT_MD_PROP_BAR_IDX, &vsec_bar, sizeof(vsec_bar));
> + if (ret) {
> + xmgnt_err(xm, "add vsec bar idx failed, ret %d", ret);
> + goto failed;
> + }
> +
> + vsec_off = cpu_to_be64(((u64)off_high << 32) | (off_low & ~0xfU));
> + ret = xrt_md_set_prop(dev, dtb, XRT_MD_NODE_VSEC, NULL,
> + XRT_MD_PROP_OFFSET, &vsec_off, sizeof(vsec_off));
> + if (ret) {
> + xmgnt_err(xm, "add vsec offset failed, ret %d", ret);
> + goto failed;
> + }
> +
> +failed:
> + return ret;
> +}
> +
> +static int xmgnt_create_root_metadata(struct xmgnt *xm, char **root_dtb)
> +{
> + char *dtb = NULL;
> + int ret;
> +
> + ret = xrt_md_create(XMGNT_DEV(xm), &dtb);
> + if (ret) {
> + xmgnt_err(xm, "create metadata failed, ret %d", ret);
> + goto failed;
> + }
> +
> + ret = xmgnt_add_vsec_node(xm, dtb);
> + if (ret == -ENOENT) {
> + /*
> + * We may be dealing with a MFG board.
> + * Try vsec-golden which will bring up all hard-coded leaves
> + * at hard-coded offsets.
> + */
> + ret = xroot_add_simple_node(xm->root, dtb, XRT_MD_NODE_VSEC_GOLDEN);
> + } else if (ret == 0) {
> + ret = xroot_add_simple_node(xm->root, dtb, XRT_MD_NODE_MGNT_MAIN);
> + }
> + if (ret)
> + goto failed;
> +
> + *root_dtb = dtb;
> + return 0;
> +
> +failed:
> + vfree(dtb);
> + return ret;
> +}
> +
> +static ssize_t ready_show(struct device *dev,
> + struct device_attribute *da,
> + char *buf)
> +{
> + struct pci_dev *pdev = to_pci_dev(dev);
> + struct xmgnt *xm = pci_get_drvdata(pdev);
> +
> + return sprintf(buf, "%d\n", xm->ready);
> +}
> +static DEVICE_ATTR_RO(ready);
> +
> +static struct attribute *xmgnt_root_attrs[] = {
> + &dev_attr_ready.attr,
> + NULL
> +};
> +
> +static struct attribute_group xmgnt_root_attr_group = {
> + .attrs = xmgnt_root_attrs,
> +};
> +
> +static void xmgnt_root_get_id(struct device *dev, struct xrt_root_get_id *rid)
> +{
> + struct pci_dev *pdev = to_pci_dev(dev);
> +
> + rid->xpigi_vendor_id = pdev->vendor;
> + rid->xpigi_device_id = pdev->device;
> + rid->xpigi_sub_vendor_id = pdev->subsystem_vendor;
> + rid->xpigi_sub_device_id = pdev->subsystem_device;
> +}
> +
> +static int xmgnt_root_get_resource(struct device *dev, struct xrt_root_get_res *res)
> +{
> + struct pci_dev *pdev = to_pci_dev(dev);
> + struct xmgnt *xm;
> +
> + xm = pci_get_drvdata(pdev);
> + if (res->xpigr_region_id > PCI_STD_RESOURCE_END) {
> + xmgnt_err(xm, "Invalid bar idx %d", res->xpigr_region_id);
> + return -EINVAL;
> + }
> +
> + res->xpigr_res = &pdev->resource[res->xpigr_region_id];
> + return 0;
> +}
> +
> +static struct xroot_physical_function_callback xmgnt_xroot_pf_cb = {
> + .xpc_get_id = xmgnt_root_get_id,
> + .xpc_get_resource = xmgnt_root_get_resource,
> + .xpc_hot_reset = xmgnt_root_hot_reset,
> +};
> +
> +static int xmgnt_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> +{
> + int ret;
> + struct device *dev = &pdev->dev;
> + struct xmgnt *xm = devm_kzalloc(dev, sizeof(*xm), GFP_KERNEL);
> + char *dtb = NULL;
> +
> + if (!xm)
> + return -ENOMEM;
> + xm->pdev = pdev;
> + pci_set_drvdata(pdev, xm);
> +
> + ret = xmgnt_config_pci(xm);
> + if (ret)
> + goto failed;
> +
> + ret = xroot_probe(&pdev->dev, &xmgnt_xroot_pf_cb, &xm->root);
> + if (ret)
> + goto failed;
> +
> + ret = xmgnt_create_root_metadata(xm, &dtb);
> + if (ret)
> + goto failed_metadata;
> +
> + ret = xroot_create_group(xm->root, dtb);
> + vfree(dtb);
> + if (ret)
> + xmgnt_err(xm, "failed to create root group: %d", ret);
> +
> + if (!xroot_wait_for_bringup(xm->root))
> + xmgnt_err(xm, "failed to bringup all groups");
> + else
> + xm->ready = true;
> +
> + ret = sysfs_create_group(&pdev->dev.kobj, &xmgnt_root_attr_group);
> + if (ret) {
> + /* Warning instead of failing the probe. */
> + xmgnt_warn(xm, "create xmgnt root attrs failed: %d", ret);
> + }
> +
> + xroot_broadcast(xm->root, XRT_EVENT_POST_CREATION);
> + xmgnt_info(xm, "%s started successfully", XMGNT_MODULE_NAME);
> + return 0;
> +
> +failed_metadata:
> + xroot_remove(xm->root);
> +failed:
> + pci_set_drvdata(pdev, NULL);
> + return ret;
> +}
> +
> +static void xmgnt_remove(struct pci_dev *pdev)
> +{
> + struct xmgnt *xm = pci_get_drvdata(pdev);
> +
> + xroot_broadcast(xm->root, XRT_EVENT_PRE_REMOVAL);
> + sysfs_remove_group(&pdev->dev.kobj, &xmgnt_root_attr_group);
> + xroot_remove(xm->root);
> + pci_disable_pcie_error_reporting(xm->pdev);
> + xmgnt_info(xm, "%s cleaned up successfully", XMGNT_MODULE_NAME);
> +}
> +
> +static struct pci_driver xmgnt_driver = {
> + .name = XMGNT_MODULE_NAME,
> + .id_table = xmgnt_pci_ids,
> + .probe = xmgnt_probe,
> + .remove = xmgnt_remove,
> +};
> +
> +static int __init xmgnt_init(void)
> +{
> + int res = 0;
> +
> + res = xmgnt_register_leaf();
> + if (res)
> + return res;
> +
> + xmgnt_class = class_create(THIS_MODULE, XMGNT_MODULE_NAME);
> + if (IS_ERR(xmgnt_class))
> + return PTR_ERR(xmgnt_class);
> +
> + res = pci_register_driver(&xmgnt_driver);
> + if (res) {
> + class_destroy(xmgnt_class);
> + return res;
> + }
> +
> + return 0;
> +}
> +
> +static __exit void xmgnt_exit(void)
> +{
> + pci_unregister_driver(&xmgnt_driver);
> + class_destroy(xmgnt_class);
> + xmgnt_unregister_leaf();
> +}
> +
> +module_init(xmgnt_init);
> +module_exit(xmgnt_exit);
> +
> +MODULE_DEVICE_TABLE(pci, xmgnt_pci_ids);
> +MODULE_VERSION(XMGNT_DRIVER_VERSION);
> +MODULE_AUTHOR("XRT Team <runtime@xilinx.com>");
> +MODULE_DESCRIPTION("Xilinx Alveo management function driver");
> +MODULE_LICENSE("GPL v2");