1// SPDX-License-Identifier: MIT
  2/*
  3 * Copyright © 2023-2024 Intel Corporation
  4 */
  5
  6#include <drm/drm_managed.h>
  7
  8#include "xe_assert.h"
  9#include "xe_device.h"
 10#include "xe_module.h"
 11#include "xe_sriov.h"
 12#include "xe_sriov_pf.h"
 13#include "xe_sriov_printk.h"
 14
 15static unsigned int wanted_max_vfs(struct xe_device *xe)
 16{
 17	return xe_modparam.max_vfs;
 18}
 19
 20static int pf_reduce_totalvfs(struct xe_device *xe, int limit)
 21{
 22	struct device *dev = xe->drm.dev;
 23	struct pci_dev *pdev = to_pci_dev(dev);
 24	int err;
 25
 26	err = pci_sriov_set_totalvfs(pdev, limit);
 27	if (err)
 28		xe_sriov_notice(xe, "Failed to set number of VFs to %d (%pe)\n",
 29				limit, ERR_PTR(err));
 30	return err;
 31}
 32
 33static bool pf_continue_as_native(struct xe_device *xe, const char *why)
 34{
 35	xe_sriov_dbg(xe, "%s, continuing as native\n", why);
 36	pf_reduce_totalvfs(xe, 0);
 37	return false;
 38}
 39
 40/**
 41 * xe_sriov_pf_readiness - Check if PF functionality can be enabled.
 42 * @xe: the &xe_device to check
 43 *
 44 * This function is called as part of the SR-IOV probe to validate if all
 45 * PF prerequisites are satisfied and we can continue with enabling PF mode.
 46 *
 47 * Return: true if the PF mode can be turned on.
 48 */
 49bool xe_sriov_pf_readiness(struct xe_device *xe)
 50{
 51	struct device *dev = xe->drm.dev;
 52	struct pci_dev *pdev = to_pci_dev(dev);
 53	int totalvfs = pci_sriov_get_totalvfs(pdev);
 54	int newlimit = min_t(u16, wanted_max_vfs(xe), totalvfs);
 55
 56	xe_assert(xe, totalvfs <= U16_MAX);
 57
 58	if (!dev_is_pf(dev))
 59		return false;
 60
 61	if (!xe_device_uc_enabled(xe))
 62		return pf_continue_as_native(xe, "Guc submission disabled");
 63
 64	if (!newlimit)
 65		return pf_continue_as_native(xe, "all VFs disabled");
 66
 67	pf_reduce_totalvfs(xe, newlimit);
 68
 69	xe->sriov.pf.device_total_vfs = totalvfs;
 70	xe->sriov.pf.driver_max_vfs = newlimit;
 71
 72	return true;
 73}
 74
 75/**
 76 * xe_sriov_pf_init_early - Initialize SR-IOV PF specific data.
 77 * @xe: the &xe_device to initialize
 78 *
 79 * Return: 0 on success or a negative error code on failure.
 80 */
 81int xe_sriov_pf_init_early(struct xe_device *xe)
 82{
 83	xe_assert(xe, IS_SRIOV_PF(xe));
 84
 85	return drmm_mutex_init(&xe->drm, &xe->sriov.pf.master_lock);
 86}
 87
 88/**
 89 * xe_sriov_pf_print_vfs_summary - Print SR-IOV PF information.
 90 * @xe: the &xe_device to print info from
 91 * @p: the &drm_printer
 92 *
 93 * Print SR-IOV PF related information into provided DRM printer.
 94 */
 95void xe_sriov_pf_print_vfs_summary(struct xe_device *xe, struct drm_printer *p)
 96{
 97	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
 98
 99	xe_assert(xe, IS_SRIOV_PF(xe));
100
101	drm_printf(p, "total: %u\n", xe->sriov.pf.device_total_vfs);
102	drm_printf(p, "supported: %u\n", xe->sriov.pf.driver_max_vfs);
103	drm_printf(p, "enabled: %u\n", pci_num_vf(pdev));
104}