crdump.c

  1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
  2/* Copyright (c) 2019 Mellanox Technologies */
  3
  4#include <linux/mlx5/driver.h>
  5#include "mlx5_core.h"
  6#include "lib/pci_vsc.h"
  7#include "lib/mlx5.h"
  8
  9#define BAD_ACCESS			0xBADACCE5
 10#define MLX5_PROTECTED_CR_SCAN_CRSPACE	0x7
 11
 12static bool mlx5_crdump_enabled(struct mlx5_core_dev *dev)
 13{
 14	return !!dev->priv.health.crdump_size;
 15}
 16
 17static int mlx5_crdump_fill(struct mlx5_core_dev *dev, u32 *cr_data)
 18{
 19	u32 crdump_size = dev->priv.health.crdump_size;
 20	int i, ret;
 21
 22	for (i = 0; i < (crdump_size / 4); i++)
 23		cr_data[i] = BAD_ACCESS;
 24
 25	ret = mlx5_vsc_gw_read_block_fast(dev, cr_data, crdump_size);
 26	if (ret <= 0) {
 27		if (ret == 0)
 28			return -EIO;
 29		return ret;
 30	}
 31
 32	if (crdump_size != ret) {
 33		mlx5_core_warn(dev, "failed to read full dump, read %d out of %u\n",
 34			       ret, crdump_size);
 35		return -EINVAL;
 36	}
 37
 38	return 0;
 39}
 40
 41int mlx5_crdump_collect(struct mlx5_core_dev *dev, u32 *cr_data)
 42{
 43	int ret;
 44
 45	if (!mlx5_crdump_enabled(dev))
 46		return -ENODEV;
 47
 48	ret = mlx5_vsc_gw_lock(dev);
 49	if (ret) {
 50		mlx5_core_warn(dev, "crdump: failed to lock vsc gw err %d\n",
 51			       ret);
 52		return ret;
 53	}
 54	/* Verify no other PF is running cr-dump or sw reset */
 55	ret = mlx5_vsc_sem_set_space(dev, MLX5_SEMAPHORE_SW_RESET,
 56				     MLX5_VSC_LOCK);
 57	if (ret) {
 58		if (ret == -EBUSY)
 59			mlx5_core_info(dev, "SW reset semaphore is already in use\n");
 60		else
 61			mlx5_core_warn(dev, "Failed to lock SW reset semaphore\n");
 62		goto unlock_gw;
 63	}
 64
 65	ret = mlx5_vsc_gw_set_space(dev, MLX5_VSC_SPACE_SCAN_CRSPACE, NULL);
 66	if (ret)
 67		goto unlock_sem;
 68
 69	ret = mlx5_crdump_fill(dev, cr_data);
 70
 71unlock_sem:
 72	mlx5_vsc_sem_set_space(dev, MLX5_SEMAPHORE_SW_RESET, MLX5_VSC_UNLOCK);
 73unlock_gw:
 74	mlx5_vsc_gw_unlock(dev);
 75	return ret;
 76}
 77
 78int mlx5_crdump_enable(struct mlx5_core_dev *dev)
 79{
 80	struct mlx5_priv *priv = &dev->priv;
 81	u32 space_size;
 82	int ret;
 83
 84	if (!mlx5_core_is_pf(dev) || !mlx5_vsc_accessible(dev) ||
 85	    mlx5_crdump_enabled(dev))
 86		return 0;
 87
 88	ret = mlx5_vsc_gw_lock(dev);
 89	if (ret)
 90		return ret;
 91
 92	/* Check if space is supported and get space size */
 93	ret = mlx5_vsc_gw_set_space(dev, MLX5_VSC_SPACE_SCAN_CRSPACE,
 94				    &space_size);
 95	if (ret) {
 96		/* Unlock and mask error since space is not supported */
 97		mlx5_vsc_gw_unlock(dev);
 98		return 0;
 99	}
100
101	if (!space_size) {
102		mlx5_core_warn(dev, "Invalid Crspace size, zero\n");
103		mlx5_vsc_gw_unlock(dev);
104		return -EINVAL;
105	}
106
107	ret = mlx5_vsc_gw_unlock(dev);
108	if (ret)
109		return ret;
110
111	priv->health.crdump_size = space_size;
112	return 0;
113}
114
115void mlx5_crdump_disable(struct mlx5_core_dev *dev)
116{
117	dev->priv.health.crdump_size = 0;
118}