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}
119