blob: 8908a20065c83c73eca48ecb294a0a4ee23bcb5b [file] [log] [blame]
* CXL Flash Device Driver
* Written by: Manoj N. Kumar <>, IBM Corporation
* Matthew R. Ochs <>, IBM Corporation
* Copyright (C) 2015 IBM Corporation
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
#include <linux/async.h>
#include <linux/cdev.h>
#include <linux/irq_poll.h>
#include <linux/list.h>
#include <linux/rwsem.h>
#include <linux/types.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include "backend.h"
extern const struct file_operations cxlflash_cxl_fops;
#define MAX_CONTEXT CXLFLASH_MAX_CONTEXT /* num contexts per afu */
#define MAX_FC_PORTS CXLFLASH_MAX_FC_PORTS /* max ports per AFU */
#define LEGACY_FC_PORTS 2 /* legacy ports per AFU */
#define CHAN2PORTMASK(_x) (1 << (_x)) /* channel to port mask */
#define PORTMASK2CHAN(_x) (ilog2((_x))) /* port mask to channel */
#define PORTNUM2CHAN(_x) ((_x) - 1) /* port number to channel */
#define CXLFLASH_BLOCK_SIZE 4096 /* 4K blocks */
#define CXLFLASH_MAX_XFER_SIZE 16777216 /* 16MB transfer */
* max_sectors
* in units of
* 512 byte
* sectors
#define MAX_RHT_PER_CONTEXT (PAGE_SIZE / sizeof(struct sisl_rht_entry))
/* AFU command retry limit */
#define MC_RETRY_CNT 5 /* Sufficient for SCSI and certain AFU errors */
/* Command management definitions */
/* RRQ for master issued cmds */
/* SQ for master issued cmds */
/* Hardware queue definitions */
#define PRIMARY_HWQ 0
static inline void check_sizes(void)
/* AFU defines a fixed size of 4K for command buffers (borrow 4K page define) */
enum cxlflash_lr_state {
enum cxlflash_init_state {
enum cxlflash_state {
STATE_PROBING, /* Initial state during probe */
STATE_PROBED, /* Temporary state, probe completed but EEH occurred */
STATE_NORMAL, /* Normal running state, everything good */
STATE_RESET, /* Reset state, trying to reset/recover */
STATE_FAILTERM /* Failed/terminating state, error out users/threads */
enum cxlflash_hwq_mode {
HWQ_MODE_RR, /* Roundrobin (default) */
HWQ_MODE_TAG, /* Distribute based on block MQ tag */
HWQ_MODE_CPU, /* CPU affinity */
* Each context has its own set of resource handles that is visible
* only from that context.
struct cxlflash_cfg {
struct afu *afu;
const struct cxlflash_backend_ops *ops;
struct pci_dev *dev;
struct pci_device_id *dev_id;
struct Scsi_Host *host;
int num_fc_ports;
struct cdev cdev;
struct device *chardev;
ulong cxlflash_regs_pci;
struct work_struct work_q;
enum cxlflash_init_state init_state;
enum cxlflash_lr_state lr_state;
int lr_port;
atomic_t scan_host_needed;
void *afu_cookie;
atomic_t recovery_threads;
struct mutex ctx_recovery_mutex;
struct mutex ctx_tbl_list_mutex;
struct rw_semaphore ioctl_rwsem;
struct ctx_info *ctx_tbl[MAX_CONTEXT];
struct list_head ctx_err_recovery; /* contexts w/ recovery pending */
struct file_operations cxl_fops;
/* Parameters that are LUN table related */
int last_lun_index[MAX_FC_PORTS];
int promote_lun_index;
struct list_head lluns; /* list of llun_info structs */
wait_queue_head_t tmf_waitq;
spinlock_t tmf_slock;
bool tmf_active;
bool ws_unmap; /* Write-same unmap supported */
wait_queue_head_t reset_waitq;
enum cxlflash_state state;
async_cookie_t async_reset_cookie;
struct afu_cmd {
struct sisl_ioarcb rcb; /* IOARCB (cache line aligned) */
struct sisl_ioasa sa; /* IOASA must follow IOARCB */
struct afu *parent;
struct scsi_cmnd *scp;
struct completion cevent;
struct list_head queue;
u32 hwq_index;
u8 cmd_tmf:1,
struct list_head list; /* Pending commands link */
/* As per the SISLITE spec the IOARCB EA has to be 16-byte aligned.
* However for performance reasons the IOARCB/IOASA should be
* cache line aligned.
} __aligned(cache_line_size());
static inline struct afu_cmd *sc_to_afuc(struct scsi_cmnd *sc)
return PTR_ALIGN(scsi_cmd_priv(sc), __alignof__(struct afu_cmd));
static inline struct afu_cmd *sc_to_afuci(struct scsi_cmnd *sc)
struct afu_cmd *afuc = sc_to_afuc(sc);
return afuc;
static inline struct afu_cmd *sc_to_afucz(struct scsi_cmnd *sc)
struct afu_cmd *afuc = sc_to_afuc(sc);
memset(afuc, 0, sizeof(*afuc));
return sc_to_afuci(sc);
struct hwq {
/* Stuff requiring alignment go first. */
struct sisl_ioarcb sq[NUM_SQ_ENTRY]; /* 16K SQ */
u64 rrq_entry[NUM_RRQ_ENTRY]; /* 2K RRQ */
/* Beware of alignment till here. Preferably introduce new
* fields after this point
struct afu *afu;
void *ctx_cookie;
struct sisl_host_map __iomem *host_map; /* MC host map */
struct sisl_ctrl_map __iomem *ctrl_map; /* MC control map */
ctx_hndl_t ctx_hndl; /* master's context handle */
u32 index; /* Index of this hwq */
int num_irqs; /* Number of interrupts requested for context */
struct list_head pending_cmds; /* Commands pending completion */
atomic_t hsq_credits;
spinlock_t hsq_slock; /* Hardware send queue lock */
struct sisl_ioarcb *hsq_start;
struct sisl_ioarcb *hsq_end;
struct sisl_ioarcb *hsq_curr;
spinlock_t hrrq_slock;
u64 *hrrq_start;
u64 *hrrq_end;
u64 *hrrq_curr;
bool toggle;
bool hrrq_online;
s64 room;
struct irq_poll irqpoll;
} __aligned(cache_line_size());
struct afu {
struct hwq hwqs[CXLFLASH_MAX_HWQS];
int (*send_cmd)(struct afu *afu, struct afu_cmd *cmd);
int (*context_reset)(struct hwq *hwq);
/* AFU HW */
struct cxlflash_afu_map __iomem *afu_map; /* entire MMIO map */
atomic_t cmds_active; /* Number of currently active AFU commands */
struct mutex sync_active; /* Mutex to serialize AFU commands */
u64 hb;
u32 internal_lun; /* User-desired LUN mode for this AFU */
u32 num_hwqs; /* Number of hardware queues */
u32 desired_hwqs; /* Desired h/w queues, effective on AFU reset */
enum cxlflash_hwq_mode hwq_mode; /* Steering mode for h/w queues */
u32 hwq_rr_count; /* Count to distribute traffic for roundrobin */
char version[16];
u64 interface_version;
u32 irqpoll_weight;
struct cxlflash_cfg *parent; /* Pointer back to parent cxlflash_cfg */
static inline struct hwq *get_hwq(struct afu *afu, u32 index)
return &afu->hwqs[index];
static inline bool afu_is_irqpoll_enabled(struct afu *afu)
return !!afu->irqpoll_weight;
static inline bool afu_has_cap(struct afu *afu, u64 cap)
u64 afu_cap = afu->interface_version >> SISL_INTVER_CAP_SHIFT;
return afu_cap & cap;
static inline bool afu_is_ocxl_lisn(struct afu *afu)
return afu_has_cap(afu, SISL_INTVER_CAP_OCXL_LISN);
static inline bool afu_is_afu_debug(struct afu *afu)
return afu_has_cap(afu, SISL_INTVER_CAP_AFU_DEBUG);
static inline bool afu_is_lun_provision(struct afu *afu)
return afu_has_cap(afu, SISL_INTVER_CAP_LUN_PROVISION);
static inline bool afu_is_sq_cmd_mode(struct afu *afu)
return afu_has_cap(afu, SISL_INTVER_CAP_SQ_CMD_MODE);
static inline bool afu_is_ioarrin_cmd_mode(struct afu *afu)
return afu_has_cap(afu, SISL_INTVER_CAP_IOARRIN_CMD_MODE);
static inline u64 lun_to_lunid(u64 lun)
__be64 lun_id;
int_to_scsilun(lun, (struct scsi_lun *)&lun_id);
return be64_to_cpu(lun_id);
static inline struct fc_port_bank __iomem *get_fc_port_bank(
struct cxlflash_cfg *cfg, int i)
struct afu *afu = cfg->afu;
return &afu->afu_map->[CHAN2PORTBANK(i)];
static inline __be64 __iomem *get_fc_port_regs(struct cxlflash_cfg *cfg, int i)
struct fc_port_bank __iomem *fcpb = get_fc_port_bank(cfg, i);
return &fcpb->fc_port_regs[CHAN2BANKPORT(i)][0];
static inline __be64 __iomem *get_fc_port_luns(struct cxlflash_cfg *cfg, int i)
struct fc_port_bank __iomem *fcpb = get_fc_port_bank(cfg, i);
return &fcpb->fc_port_luns[CHAN2BANKPORT(i)][0];
int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t c, res_hndl_t r, u8 mode);
void cxlflash_list_init(void);
void cxlflash_term_global_luns(void);
void cxlflash_free_errpage(void);
int cxlflash_ioctl(struct scsi_device *sdev, int cmd, void __user *arg);
void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *cfg);
int cxlflash_mark_contexts_error(struct cxlflash_cfg *cfg);
void cxlflash_term_local_luns(struct cxlflash_cfg *cfg);
void cxlflash_restore_luntable(struct cxlflash_cfg *cfg);
#endif /* ifndef _CXLFLASH_COMMON_H */