1 /*
2 * CXL Flash Device Driver
3 *
4 * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
5 * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
6 *
7 * Copyright (C) 2015 IBM Corporation
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 */
14
15 #ifndef _CXLFLASH_COMMON_H
16 #define _CXLFLASH_COMMON_H
17
18 #include <linux/list.h>
19 #include <linux/rwsem.h>
20 #include <linux/types.h>
21 #include <scsi/scsi.h>
22 #include <scsi/scsi_device.h>
23
24 extern const struct file_operations cxlflash_cxl_fops;
25
26 #define MAX_CONTEXT CXLFLASH_MAX_CONTEXT /* num contexts per afu */
27
28 #define CXLFLASH_BLOCK_SIZE 4096 /* 4K blocks */
29 #define CXLFLASH_MAX_XFER_SIZE 16777216 /* 16MB transfer */
30 #define CXLFLASH_MAX_SECTORS (CXLFLASH_MAX_XFER_SIZE/512) /* SCSI wants
31 max_sectors
32 in units of
33 512 byte
34 sectors
35 */
36
37 #define NUM_RRQ_ENTRY 16 /* for master issued cmds */
38 #define MAX_RHT_PER_CONTEXT (PAGE_SIZE / sizeof(struct sisl_rht_entry))
39
40 /* AFU command retry limit */
41 #define MC_RETRY_CNT 5 /* sufficient for SCSI check and
42 certain AFU errors */
43
44 /* Command management definitions */
45 #define CXLFLASH_NUM_CMDS (2 * CXLFLASH_MAX_CMDS) /* Must be a pow2 for
46 alignment and more
47 efficient array
48 index derivation
49 */
50
51 #define CXLFLASH_MAX_CMDS 16
52 #define CXLFLASH_MAX_CMDS_PER_LUN CXLFLASH_MAX_CMDS
53
54
check_sizes(void)55 static inline void check_sizes(void)
56 {
57 BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_NUM_CMDS);
58 }
59
60 /* AFU defines a fixed size of 4K for command buffers (borrow 4K page define) */
61 #define CMD_BUFSIZE SIZE_4K
62
63 /* flags in IOA status area for host use */
64 #define B_DONE 0x01
65 #define B_ERROR 0x02 /* set with B_DONE */
66 #define B_TIMEOUT 0x04 /* set with B_DONE & B_ERROR */
67
68 enum cxlflash_lr_state {
69 LINK_RESET_INVALID,
70 LINK_RESET_REQUIRED,
71 LINK_RESET_COMPLETE
72 };
73
74 enum cxlflash_init_state {
75 INIT_STATE_NONE,
76 INIT_STATE_PCI,
77 INIT_STATE_AFU,
78 INIT_STATE_SCSI
79 };
80
81 enum cxlflash_state {
82 STATE_NORMAL, /* Normal running state, everything good */
83 STATE_RESET, /* Reset state, trying to reset/recover */
84 STATE_FAILTERM /* Failed/terminating state, error out users/threads */
85 };
86
87 /*
88 * Each context has its own set of resource handles that is visible
89 * only from that context.
90 */
91
92 struct cxlflash_cfg {
93 struct afu *afu;
94 struct cxl_context *mcctx;
95
96 struct pci_dev *dev;
97 struct pci_device_id *dev_id;
98 struct Scsi_Host *host;
99
100 ulong cxlflash_regs_pci;
101
102 struct work_struct work_q;
103 enum cxlflash_init_state init_state;
104 enum cxlflash_lr_state lr_state;
105 int lr_port;
106 atomic_t scan_host_needed;
107
108 struct cxl_afu *cxl_afu;
109 struct pci_dev *parent_dev;
110
111 atomic_t recovery_threads;
112 struct mutex ctx_recovery_mutex;
113 struct mutex ctx_tbl_list_mutex;
114 struct rw_semaphore ioctl_rwsem;
115 struct ctx_info *ctx_tbl[MAX_CONTEXT];
116 struct list_head ctx_err_recovery; /* contexts w/ recovery pending */
117 struct file_operations cxl_fops;
118
119 /* Parameters that are LUN table related */
120 int last_lun_index[CXLFLASH_NUM_FC_PORTS];
121 int promote_lun_index;
122 struct list_head lluns; /* list of llun_info structs */
123
124 wait_queue_head_t tmf_waitq;
125 spinlock_t tmf_slock;
126 bool tmf_active;
127 wait_queue_head_t reset_waitq;
128 enum cxlflash_state state;
129 };
130
131 struct afu_cmd {
132 struct sisl_ioarcb rcb; /* IOARCB (cache line aligned) */
133 struct sisl_ioasa sa; /* IOASA must follow IOARCB */
134 spinlock_t slock;
135 struct completion cevent;
136 char *buf; /* per command buffer */
137 struct afu *parent;
138 int slot;
139 atomic_t free;
140
141 u8 cmd_tmf:1;
142
143 /* As per the SISLITE spec the IOARCB EA has to be 16-byte aligned.
144 * However for performance reasons the IOARCB/IOASA should be
145 * cache line aligned.
146 */
147 } __aligned(cache_line_size());
148
149 struct afu {
150 /* Stuff requiring alignment go first. */
151
152 u64 rrq_entry[NUM_RRQ_ENTRY]; /* 128B RRQ */
153 /*
154 * Command & data for AFU commands.
155 */
156 struct afu_cmd cmd[CXLFLASH_NUM_CMDS];
157
158 /* Beware of alignment till here. Preferably introduce new
159 * fields after this point
160 */
161
162 /* AFU HW */
163 struct cxl_ioctl_start_work work;
164 struct cxlflash_afu_map __iomem *afu_map; /* entire MMIO map */
165 struct sisl_host_map __iomem *host_map; /* MC host map */
166 struct sisl_ctrl_map __iomem *ctrl_map; /* MC control map */
167
168 ctx_hndl_t ctx_hndl; /* master's context handle */
169 u64 *hrrq_start;
170 u64 *hrrq_end;
171 u64 *hrrq_curr;
172 bool toggle;
173 bool read_room;
174 atomic64_t room;
175 u64 hb;
176 u32 cmd_couts; /* Number of command checkouts */
177 u32 internal_lun; /* User-desired LUN mode for this AFU */
178
179 char version[16];
180 u64 interface_version;
181
182 struct cxlflash_cfg *parent; /* Pointer back to parent cxlflash_cfg */
183
184 };
185
lun_to_lunid(u64 lun)186 static inline u64 lun_to_lunid(u64 lun)
187 {
188 __be64 lun_id;
189
190 int_to_scsilun(lun, (struct scsi_lun *)&lun_id);
191 return be64_to_cpu(lun_id);
192 }
193
194 int cxlflash_afu_sync(struct afu *, ctx_hndl_t, res_hndl_t, u8);
195 void cxlflash_list_init(void);
196 void cxlflash_term_global_luns(void);
197 void cxlflash_free_errpage(void);
198 int cxlflash_ioctl(struct scsi_device *, int, void __user *);
199 void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *);
200 int cxlflash_mark_contexts_error(struct cxlflash_cfg *);
201 void cxlflash_term_local_luns(struct cxlflash_cfg *);
202 void cxlflash_restore_luntable(struct cxlflash_cfg *);
203
204 #endif /* ifndef _CXLFLASH_COMMON_H */
205