drivers/scsi/cxlflash/common.h

   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/irq_poll.h>
  19 #include <linux/list.h>
  20 #include <linux/rwsem.h>
  21 #include <linux/types.h>
  22 #include <scsi/scsi.h>
  23 #include <scsi/scsi_cmnd.h>
  24 #include <scsi/scsi_device.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 check and
  52                                    certain AFU errors */
  53
  54 /* Command management definitions */
  55 #define CXLFLASH_NUM_CMDS       (2 * CXLFLASH_MAX_CMDS) /* Must be a pow2 for
  56                                                            alignment and more
  57                                                            efficient array
  58                                                            index derivation
  59                                                          */
  60
  61 #define CXLFLASH_MAX_CMDS               256
  62 #define CXLFLASH_MAX_CMDS_PER_LUN       CXLFLASH_MAX_CMDS
  63
  64 /* RRQ for master issued cmds */
  65 #define NUM_RRQ_ENTRY                   CXLFLASH_MAX_CMDS
  66
  67 /* SQ for master issued cmds */
  68 #define NUM_SQ_ENTRY                    CXLFLASH_MAX_CMDS
  69
  70
  71 static inline void check_sizes(void)
  72 {
  73         BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_NUM_FC_PORTS_PER_BANK);
  74 }
  75
  76 /* AFU defines a fixed size of 4K for command buffers (borrow 4K page define) */
  77 #define CMD_BUFSIZE     SIZE_4K
  78
  79 enum cxlflash_lr_state {
  80         LINK_RESET_INVALID,
  81         LINK_RESET_REQUIRED,
  82         LINK_RESET_COMPLETE
  83 };
  84
  85 enum cxlflash_init_state {
  86         INIT_STATE_NONE,
  87         INIT_STATE_PCI,
  88         INIT_STATE_AFU,
  89         INIT_STATE_SCSI
  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 /*
 101  * Each context has its own set of resource handles that is visible
 102  * only from that context.
 103  */
 104
 105 struct cxlflash_cfg {
 106         struct afu *afu;
 107         struct cxl_context *mcctx;
 108
 109         struct pci_dev *dev;
 110         struct pci_device_id *dev_id;
 111         struct Scsi_Host *host;
 112         int num_fc_ports;
 113
 114         ulong cxlflash_regs_pci;
 115
 116         struct work_struct work_q;
 117         enum cxlflash_init_state init_state;
 118         enum cxlflash_lr_state lr_state;
 119         int lr_port;
 120         atomic_t scan_host_needed;
 121
 122         struct cxl_afu *cxl_afu;
 123
 124         atomic_t recovery_threads;
 125         struct mutex ctx_recovery_mutex;
 126         struct mutex ctx_tbl_list_mutex;
 127         struct rw_semaphore ioctl_rwsem;
 128         struct ctx_info *ctx_tbl[MAX_CONTEXT];
 129         struct list_head ctx_err_recovery; /* contexts w/ recovery pending */
 130         struct file_operations cxl_fops;
 131
 132         /* Parameters that are LUN table related */
 133         int last_lun_index[MAX_FC_PORTS];
 134         int promote_lun_index;
 135         struct list_head lluns; /* list of llun_info structs */
 136
 137         wait_queue_head_t tmf_waitq;
 138         spinlock_t tmf_slock;
 139         bool tmf_active;
 140         wait_queue_head_t reset_waitq;
 141         enum cxlflash_state state;
 142 };
 143
 144 struct afu_cmd {
 145         struct sisl_ioarcb rcb; /* IOARCB (cache line aligned) */
 146         struct sisl_ioasa sa;   /* IOASA must follow IOARCB */
 147         struct afu *parent;
 148         struct scsi_cmnd *scp;
 149         struct completion cevent;
 150         struct list_head queue;
 151
 152         u8 cmd_tmf:1;
 153
 154         /* As per the SISLITE spec the IOARCB EA has to be 16-byte aligned.
 155          * However for performance reasons the IOARCB/IOASA should be
 156          * cache line aligned.
 157          */
 158 } __aligned(cache_line_size());
 159
 160 static inline struct afu_cmd *sc_to_afuc(struct scsi_cmnd *sc)
 161 {
 162         return PTR_ALIGN(scsi_cmd_priv(sc), __alignof__(struct afu_cmd));
 163 }
 164
 165 static inline struct afu_cmd *sc_to_afucz(struct scsi_cmnd *sc)
 166 {
 167         struct afu_cmd *afuc = sc_to_afuc(sc);
 168
 169         memset(afuc, 0, sizeof(*afuc));
 170         return afuc;
 171 }
 172
 173 struct afu {
 174         /* Stuff requiring alignment go first. */
 175         struct sisl_ioarcb sq[NUM_SQ_ENTRY];            /* 16K SQ */
 176         u64 rrq_entry[NUM_RRQ_ENTRY];                   /* 2K RRQ */
 177
 178         /* Beware of alignment till here. Preferably introduce new
 179          * fields after this point
 180          */
 181
 182         int (*send_cmd)(struct afu *, struct afu_cmd *);
 183         void (*context_reset)(struct afu_cmd *);
 184
 185         /* AFU HW */
 186         struct cxl_ioctl_start_work work;
 187         struct cxlflash_afu_map __iomem *afu_map;       /* entire MMIO map */
 188         struct sisl_host_map __iomem *host_map;         /* MC host map */
 189         struct sisl_ctrl_map __iomem *ctrl_map;         /* MC control map */
 190
 191         ctx_hndl_t ctx_hndl;    /* master's context handle */
 192
 193         atomic_t hsq_credits;
 194         spinlock_t hsq_slock;
 195         struct sisl_ioarcb *hsq_start;
 196         struct sisl_ioarcb *hsq_end;
 197         struct sisl_ioarcb *hsq_curr;
 198         spinlock_t hrrq_slock;
 199         u64 *hrrq_start;
 200         u64 *hrrq_end;
 201         u64 *hrrq_curr;
 202         bool toggle;
 203         atomic_t cmds_active;   /* Number of currently active AFU commands */
 204         s64 room;
 205         spinlock_t rrin_slock; /* Lock to rrin queuing and cmd_room updates */
 206         u64 hb;
 207         u32 internal_lun;       /* User-desired LUN mode for this AFU */
 208
 209         char version[16];
 210         u64 interface_version;
 211
 212         u32 irqpoll_weight;
 213         struct irq_poll irqpoll;
 214         struct cxlflash_cfg *parent; /* Pointer back to parent cxlflash_cfg */
 215
 216 };
 217
 218 static inline bool afu_is_irqpoll_enabled(struct afu *afu)
 219 {
 220         return !!afu->irqpoll_weight;
 221 }
 222
 223 static inline bool afu_is_cmd_mode(struct afu *afu, u64 cmd_mode)
 224 {
 225         u64 afu_cap = afu->interface_version >> SISL_INTVER_CAP_SHIFT;
 226
 227         return afu_cap & cmd_mode;
 228 }
 229
 230 static inline bool afu_is_sq_cmd_mode(struct afu *afu)
 231 {
 232         return afu_is_cmd_mode(afu, SISL_INTVER_CAP_SQ_CMD_MODE);
 233 }
 234
 235 static inline bool afu_is_ioarrin_cmd_mode(struct afu *afu)
 236 {
 237         return afu_is_cmd_mode(afu, SISL_INTVER_CAP_IOARRIN_CMD_MODE);
 238 }
 239
 240 static inline u64 lun_to_lunid(u64 lun)
 241 {
 242         __be64 lun_id;
 243
 244         int_to_scsilun(lun, (struct scsi_lun *)&lun_id);
 245         return be64_to_cpu(lun_id);
 246 }
 247
 248 static inline struct fc_port_bank __iomem *get_fc_port_bank(
 249                                             struct cxlflash_cfg *cfg, int i)
 250 {
 251         struct afu *afu = cfg->afu;
 252
 253         return &afu->afu_map->global.bank[CHAN2PORTBANK(i)];
 254 }
 255
 256 static inline __be64 __iomem *get_fc_port_regs(struct cxlflash_cfg *cfg, int i)
 257 {
 258         struct fc_port_bank __iomem *fcpb = get_fc_port_bank(cfg, i);
 259
 260         return &fcpb->fc_port_regs[CHAN2BANKPORT(i)][0];
 261 }
 262
 263 static inline __be64 __iomem *get_fc_port_luns(struct cxlflash_cfg *cfg, int i)
 264 {
 265         struct fc_port_bank __iomem *fcpb = get_fc_port_bank(cfg, i);
 266
 267         return &fcpb->fc_port_luns[CHAN2BANKPORT(i)][0];
 268 }
 269
 270 int cxlflash_afu_sync(struct afu *, ctx_hndl_t, res_hndl_t, u8);
 271 void cxlflash_list_init(void);
 272 void cxlflash_term_global_luns(void);
 273 void cxlflash_free_errpage(void);
 274 int cxlflash_ioctl(struct scsi_device *, int, void __user *);
 275 void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *);
 276 int cxlflash_mark_contexts_error(struct cxlflash_cfg *);
 277 void cxlflash_term_local_luns(struct cxlflash_cfg *);
 278 void cxlflash_restore_luntable(struct cxlflash_cfg *);
 279
 280 #endif /* ifndef _CXLFLASH_COMMON_H */