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Diffstat (limited to 'drivers/scsi/cxlflash/common.h')
| -rw-r--r-- | drivers/scsi/cxlflash/common.h | 340 |
1 files changed, 340 insertions, 0 deletions
diff --git a/drivers/scsi/cxlflash/common.h b/drivers/scsi/cxlflash/common.h new file mode 100644 index 0000000000..de6229e27b --- /dev/null +++ b/drivers/scsi/cxlflash/common.h @@ -0,0 +1,340 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * CXL Flash Device Driver + * + * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation + * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation + * + * Copyright (C) 2015 IBM Corporation + */ + +#ifndef _CXLFLASH_COMMON_H +#define _CXLFLASH_COMMON_H + +#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 CHAN2PORTBANK(_x) ((_x) >> ilog2(CXLFLASH_NUM_FC_PORTS_PER_BANK)) +#define CHAN2BANKPORT(_x) ((_x) & (CXLFLASH_NUM_FC_PORTS_PER_BANK - 1)) + +#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 */ +#define CXLFLASH_MAX_SECTORS (CXLFLASH_MAX_XFER_SIZE/512) /* SCSI wants + * 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 */ +#define CXLFLASH_MAX_CMDS 256 +#define CXLFLASH_MAX_CMDS_PER_LUN CXLFLASH_MAX_CMDS + +/* RRQ for master issued cmds */ +#define NUM_RRQ_ENTRY CXLFLASH_MAX_CMDS + +/* SQ for master issued cmds */ +#define NUM_SQ_ENTRY CXLFLASH_MAX_CMDS + +/* Hardware queue definitions */ +#define CXLFLASH_DEF_HWQS 1 +#define CXLFLASH_MAX_HWQS 8 +#define PRIMARY_HWQ 0 + + +static inline void check_sizes(void) +{ + BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_NUM_FC_PORTS_PER_BANK); + BUILD_BUG_ON_NOT_POWER_OF_2(CXLFLASH_MAX_CMDS); +} + +/* AFU defines a fixed size of 4K for command buffers (borrow 4K page define) */ +#define CMD_BUFSIZE SIZE_4K + +enum cxlflash_lr_state { + LINK_RESET_INVALID, + LINK_RESET_REQUIRED, + LINK_RESET_COMPLETE +}; + +enum cxlflash_init_state { + INIT_STATE_NONE, + INIT_STATE_PCI, + INIT_STATE_AFU, + INIT_STATE_SCSI, + INIT_STATE_CDEV +}; + +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 */ + MAX_HWQ_MODE +}; + +/* + * 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, + cmd_aborted: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); + + INIT_LIST_HEAD(&afuc->queue); + 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) +{ + WARN_ON(index >= CXLFLASH_MAX_HWQS); + + 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->global.bank[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, unsigned 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 */ |