1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * CXL Flash Device Driver
4 *
5 * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
6 * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
7 *
8 * Copyright (C) 2015 IBM Corporation
9 */
10
11 #ifndef _CXLFLASH_COMMON_H
12 #define _CXLFLASH_COMMON_H
13
14 #include <linux/async.h>
15 #include <linux/cdev.h>
16 #include <linux/irq_poll.h>
17 #include <linux/list.h>
18 #include <linux/rwsem.h>
19 #include <linux/types.h>
20 #include <scsi/scsi.h>
21 #include <scsi/scsi_cmnd.h>
22 #include <scsi/scsi_device.h>
23
24 #include "backend.h"
25
26 extern const struct file_operations cxlflash_cxl_fops;
27
28 #define MAX_CONTEXT CXLFLASH_MAX_CONTEXT /* num contexts per afu */
29 #define MAX_FC_PORTS CXLFLASH_MAX_FC_PORTS /* max ports per AFU */
30 #define LEGACY_FC_PORTS 2 /* legacy ports per AFU */
31
32 #define CHAN2PORTBANK(_x) ((_x) >> ilog2(CXLFLASH_NUM_FC_PORTS_PER_BANK))
33 #define CHAN2BANKPORT(_x) ((_x) & (CXLFLASH_NUM_FC_PORTS_PER_BANK - 1))
34
35 #define CHAN2PORTMASK(_x) (1 << (_x)) /* channel to port mask */
36 #define PORTMASK2CHAN(_x) (ilog2((_x))) /* port mask to channel */
37 #define PORTNUM2CHAN(_x) ((_x) - 1) /* port number to channel */
38
39 #define CXLFLASH_BLOCK_SIZE 4096 /* 4K blocks */
40 #define CXLFLASH_MAX_XFER_SIZE 16777216 /* 16MB transfer */
41 #define CXLFLASH_MAX_SECTORS (CXLFLASH_MAX_XFER_SIZE/512) /* SCSI wants
42 * max_sectors
43 * in units of
44 * 512 byte
45 * sectors
46 */
47
48 #define MAX_RHT_PER_CONTEXT (PAGE_SIZE / sizeof(struct sisl_rht_entry))
49
50 /* AFU command retry limit */
51 #define MC_RETRY_CNT 5 /* Sufficient for SCSI and certain AFU errors */
52
53 /* Command management definitions */
54 #define CXLFLASH_MAX_CMDS 256
55 #define CXLFLASH_MAX_CMDS_PER_LUN CXLFLASH_MAX_CMDS
56
57 /* RRQ for master issued cmds */
58 #define NUM_RRQ_ENTRY CXLFLASH_MAX_CMDS
59
60 /* SQ for master issued cmds */
61 #define NUM_SQ_ENTRY CXLFLASH_MAX_CMDS
62
63 /* Hardware queue definitions */
64 #define CXLFLASH_DEF_HWQS 1
65 #define CXLFLASH_MAX_HWQS 8
66 #define PRIMARY_HWQ 0
67
68
check_sizes(void)69 static inline void check_sizes(void)
70 {
71 BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_NUM_FC_PORTS_PER_BANK);
72 BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_MAX_CMDS);
73 }
74
75 /* AFU defines a fixed size of 4K for command buffers (borrow 4K page define) */
76 #define CMD_BUFSIZE SIZE_4K
77
78 enum cxlflash_lr_state {
79 LINK_RESET_INVALID,
80 LINK_RESET_REQUIRED,
81 LINK_RESET_COMPLETE
82 };
83
84 enum cxlflash_init_state {
85 INIT_STATE_NONE,
86 INIT_STATE_PCI,
87 INIT_STATE_AFU,
88 INIT_STATE_SCSI,
89 INIT_STATE_CDEV
90 };
91
92 enum cxlflash_state {
93 STATE_PROBING, /* Initial state during probe */
94 STATE_PROBED, /* Temporary state, probe completed but EEH occurred */
95 STATE_NORMAL, /* Normal running state, everything good */
96 STATE_RESET, /* Reset state, trying to reset/recover */
97 STATE_FAILTERM /* Failed/terminating state, error out users/threads */
98 };
99
100 enum cxlflash_hwq_mode {
101 HWQ_MODE_RR, /* Roundrobin (default) */
102 HWQ_MODE_TAG, /* Distribute based on block MQ tag */
103 HWQ_MODE_CPU, /* CPU affinity */
104 MAX_HWQ_MODE
105 };
106
107 /*
108 * Each context has its own set of resource handles that is visible
109 * only from that context.
110 */
111
112 struct cxlflash_cfg {
113 struct afu *afu;
114
115 const struct cxlflash_backend_ops *ops;
116 struct pci_dev *dev;
117 struct pci_device_id *dev_id;
118 struct Scsi_Host *host;
119 int num_fc_ports;
120 struct cdev cdev;
121 struct device *chardev;
122
123 ulong cxlflash_regs_pci;
124
125 struct work_struct work_q;
126 enum cxlflash_init_state init_state;
127 enum cxlflash_lr_state lr_state;
128 int lr_port;
129 atomic_t scan_host_needed;
130
131 void *afu_cookie;
132
133 atomic_t recovery_threads;
134 struct mutex ctx_recovery_mutex;
135 struct mutex ctx_tbl_list_mutex;
136 struct rw_semaphore ioctl_rwsem;
137 struct ctx_info *ctx_tbl[MAX_CONTEXT];
138 struct list_head ctx_err_recovery; /* contexts w/ recovery pending */
139 struct file_operations cxl_fops;
140
141 /* Parameters that are LUN table related */
142 int last_lun_index[MAX_FC_PORTS];
143 int promote_lun_index;
144 struct list_head lluns; /* list of llun_info structs */
145
146 wait_queue_head_t tmf_waitq;
147 spinlock_t tmf_slock;
148 bool tmf_active;
149 bool ws_unmap; /* Write-same unmap supported */
150 wait_queue_head_t reset_waitq;
151 enum cxlflash_state state;
152 async_cookie_t async_reset_cookie;
153 };
154
155 struct afu_cmd {
156 struct sisl_ioarcb rcb; /* IOARCB (cache line aligned) */
157 struct sisl_ioasa sa; /* IOASA must follow IOARCB */
158 struct afu *parent;
159 struct scsi_cmnd *scp;
160 struct completion cevent;
161 struct list_head queue;
162 u32 hwq_index;
163
164 u8 cmd_tmf:1,
165 cmd_aborted:1;
166
167 struct list_head list; /* Pending commands link */
168
169 /* As per the SISLITE spec the IOARCB EA has to be 16-byte aligned.
170 * However for performance reasons the IOARCB/IOASA should be
171 * cache line aligned.
172 */
173 } __aligned(cache_line_size());
174
sc_to_afuc(struct scsi_cmnd * sc)175 static inline struct afu_cmd *sc_to_afuc(struct scsi_cmnd *sc)
176 {
177 return PTR_ALIGN(scsi_cmd_priv(sc), __alignof__(struct afu_cmd));
178 }
179
sc_to_afuci(struct scsi_cmnd * sc)180 static inline struct afu_cmd *sc_to_afuci(struct scsi_cmnd *sc)
181 {
182 struct afu_cmd *afuc = sc_to_afuc(sc);
183
184 INIT_LIST_HEAD(&afuc->queue);
185 return afuc;
186 }
187
sc_to_afucz(struct scsi_cmnd * sc)188 static inline struct afu_cmd *sc_to_afucz(struct scsi_cmnd *sc)
189 {
190 struct afu_cmd *afuc = sc_to_afuc(sc);
191
192 memset(afuc, 0, sizeof(*afuc));
193 return sc_to_afuci(sc);
194 }
195
196 struct hwq {
197 /* Stuff requiring alignment go first. */
198 struct sisl_ioarcb sq[NUM_SQ_ENTRY]; /* 16K SQ */
199 u64 rrq_entry[NUM_RRQ_ENTRY]; /* 2K RRQ */
200
201 /* Beware of alignment till here. Preferably introduce new
202 * fields after this point
203 */
204 struct afu *afu;
205 void *ctx_cookie;
206 struct sisl_host_map __iomem *host_map; /* MC host map */
207 struct sisl_ctrl_map __iomem *ctrl_map; /* MC control map */
208 ctx_hndl_t ctx_hndl; /* master's context handle */
209 u32 index; /* Index of this hwq */
210 int num_irqs; /* Number of interrupts requested for context */
211 struct list_head pending_cmds; /* Commands pending completion */
212
213 atomic_t hsq_credits;
214 spinlock_t hsq_slock; /* Hardware send queue lock */
215 struct sisl_ioarcb *hsq_start;
216 struct sisl_ioarcb *hsq_end;
217 struct sisl_ioarcb *hsq_curr;
218 spinlock_t hrrq_slock;
219 u64 *hrrq_start;
220 u64 *hrrq_end;
221 u64 *hrrq_curr;
222 bool toggle;
223 bool hrrq_online;
224
225 s64 room;
226
227 struct irq_poll irqpoll;
228 } __aligned(cache_line_size());
229
230 struct afu {
231 struct hwq hwqs[CXLFLASH_MAX_HWQS];
232 int (*send_cmd)(struct afu *afu, struct afu_cmd *cmd);
233 int (*context_reset)(struct hwq *hwq);
234
235 /* AFU HW */
236 struct cxlflash_afu_map __iomem *afu_map; /* entire MMIO map */
237
238 atomic_t cmds_active; /* Number of currently active AFU commands */
239 struct mutex sync_active; /* Mutex to serialize AFU commands */
240 u64 hb;
241 u32 internal_lun; /* User-desired LUN mode for this AFU */
242
243 u32 num_hwqs; /* Number of hardware queues */
244 u32 desired_hwqs; /* Desired h/w queues, effective on AFU reset */
245 enum cxlflash_hwq_mode hwq_mode; /* Steering mode for h/w queues */
246 u32 hwq_rr_count; /* Count to distribute traffic for roundrobin */
247
248 char version[16];
249 u64 interface_version;
250
251 u32 irqpoll_weight;
252 struct cxlflash_cfg *parent; /* Pointer back to parent cxlflash_cfg */
253 };
254
get_hwq(struct afu * afu,u32 index)255 static inline struct hwq *get_hwq(struct afu *afu, u32 index)
256 {
257 WARN_ON(index >= CXLFLASH_MAX_HWQS);
258
259 return &afu->hwqs[index];
260 }
261
afu_is_irqpoll_enabled(struct afu * afu)262 static inline bool afu_is_irqpoll_enabled(struct afu *afu)
263 {
264 return !!afu->irqpoll_weight;
265 }
266
afu_has_cap(struct afu * afu,u64 cap)267 static inline bool afu_has_cap(struct afu *afu, u64 cap)
268 {
269 u64 afu_cap = afu->interface_version >> SISL_INTVER_CAP_SHIFT;
270
271 return afu_cap & cap;
272 }
273
afu_is_ocxl_lisn(struct afu * afu)274 static inline bool afu_is_ocxl_lisn(struct afu *afu)
275 {
276 return afu_has_cap(afu, SISL_INTVER_CAP_OCXL_LISN);
277 }
278
afu_is_afu_debug(struct afu * afu)279 static inline bool afu_is_afu_debug(struct afu *afu)
280 {
281 return afu_has_cap(afu, SISL_INTVER_CAP_AFU_DEBUG);
282 }
283
afu_is_lun_provision(struct afu * afu)284 static inline bool afu_is_lun_provision(struct afu *afu)
285 {
286 return afu_has_cap(afu, SISL_INTVER_CAP_LUN_PROVISION);
287 }
288
afu_is_sq_cmd_mode(struct afu * afu)289 static inline bool afu_is_sq_cmd_mode(struct afu *afu)
290 {
291 return afu_has_cap(afu, SISL_INTVER_CAP_SQ_CMD_MODE);
292 }
293
afu_is_ioarrin_cmd_mode(struct afu * afu)294 static inline bool afu_is_ioarrin_cmd_mode(struct afu *afu)
295 {
296 return afu_has_cap(afu, SISL_INTVER_CAP_IOARRIN_CMD_MODE);
297 }
298
lun_to_lunid(u64 lun)299 static inline u64 lun_to_lunid(u64 lun)
300 {
301 __be64 lun_id;
302
303 int_to_scsilun(lun, (struct scsi_lun *)&lun_id);
304 return be64_to_cpu(lun_id);
305 }
306
get_fc_port_bank(struct cxlflash_cfg * cfg,int i)307 static inline struct fc_port_bank __iomem *get_fc_port_bank(
308 struct cxlflash_cfg *cfg, int i)
309 {
310 struct afu *afu = cfg->afu;
311
312 return &afu->afu_map->global.bank[CHAN2PORTBANK(i)];
313 }
314
get_fc_port_regs(struct cxlflash_cfg * cfg,int i)315 static inline __be64 __iomem *get_fc_port_regs(struct cxlflash_cfg *cfg, int i)
316 {
317 struct fc_port_bank __iomem *fcpb = get_fc_port_bank(cfg, i);
318
319 return &fcpb->fc_port_regs[CHAN2BANKPORT(i)][0];
320 }
321
get_fc_port_luns(struct cxlflash_cfg * cfg,int i)322 static inline __be64 __iomem *get_fc_port_luns(struct cxlflash_cfg *cfg, int i)
323 {
324 struct fc_port_bank __iomem *fcpb = get_fc_port_bank(cfg, i);
325
326 return &fcpb->fc_port_luns[CHAN2BANKPORT(i)][0];
327 }
328
329 int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t c, res_hndl_t r, u8 mode);
330 void cxlflash_list_init(void);
331 void cxlflash_term_global_luns(void);
332 void cxlflash_free_errpage(void);
333 int cxlflash_ioctl(struct scsi_device *sdev, unsigned int cmd,
334 void __user *arg);
335 void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *cfg);
336 int cxlflash_mark_contexts_error(struct cxlflash_cfg *cfg);
337 void cxlflash_term_local_luns(struct cxlflash_cfg *cfg);
338 void cxlflash_restore_luntable(struct cxlflash_cfg *cfg);
339
340 #endif /* ifndef _CXLFLASH_COMMON_H */
341