diff options
Diffstat (limited to 'drivers/scsi/cxlflash/main.c')
| -rw-r--r-- | drivers/scsi/cxlflash/main.c | 2494 |
1 files changed, 2494 insertions, 0 deletions
diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c new file mode 100644 index 000000000..3e3ccf16e --- /dev/null +++ b/drivers/scsi/cxlflash/main.c @@ -0,0 +1,2494 @@ +/* + * 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 + * + * 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/delay.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/pci.h> + +#include <asm/unaligned.h> + +#include <misc/cxl.h> + +#include <scsi/scsi_cmnd.h> +#include <scsi/scsi_host.h> +#include <uapi/scsi/cxlflash_ioctl.h> + +#include "main.h" +#include "sislite.h" +#include "common.h" + +MODULE_DESCRIPTION(CXLFLASH_ADAPTER_NAME); +MODULE_AUTHOR("Manoj N. Kumar <manoj@linux.vnet.ibm.com>"); +MODULE_AUTHOR("Matthew R. Ochs <mrochs@linux.vnet.ibm.com>"); +MODULE_LICENSE("GPL"); + + +/** + * cxlflash_cmd_checkout() - checks out an AFU command + * @afu: AFU to checkout from. + * + * Commands are checked out in a round-robin fashion. Note that since + * the command pool is larger than the hardware queue, the majority of + * times we will only loop once or twice before getting a command. The + * buffer and CDB within the command are initialized (zeroed) prior to + * returning. + * + * Return: The checked out command or NULL when command pool is empty. + */ +struct afu_cmd *cxlflash_cmd_checkout(struct afu *afu) +{ + int k, dec = CXLFLASH_NUM_CMDS; + struct afu_cmd *cmd; + + while (dec--) { + k = (afu->cmd_couts++ & (CXLFLASH_NUM_CMDS - 1)); + + cmd = &afu->cmd[k]; + + if (!atomic_dec_if_positive(&cmd->free)) { + pr_debug("%s: returning found index=%d\n", + __func__, cmd->slot); + memset(cmd->buf, 0, CMD_BUFSIZE); + memset(cmd->rcb.cdb, 0, sizeof(cmd->rcb.cdb)); + return cmd; + } + } + + return NULL; +} + +/** + * cxlflash_cmd_checkin() - checks in an AFU command + * @cmd: AFU command to checkin. + * + * Safe to pass commands that have already been checked in. Several + * internal tracking fields are reset as part of the checkin. Note + * that these are intentionally reset prior to toggling the free bit + * to avoid clobbering values in the event that the command is checked + * out right away. + */ +void cxlflash_cmd_checkin(struct afu_cmd *cmd) +{ + cmd->rcb.scp = NULL; + cmd->rcb.timeout = 0; + cmd->sa.ioasc = 0; + cmd->cmd_tmf = false; + cmd->sa.host_use[0] = 0; /* clears both completion and retry bytes */ + + if (unlikely(atomic_inc_return(&cmd->free) != 1)) { + pr_err("%s: Freeing cmd (%d) that is not in use!\n", + __func__, cmd->slot); + return; + } + + pr_debug("%s: released cmd %p index=%d\n", __func__, cmd, cmd->slot); +} + +/** + * process_cmd_err() - command error handler + * @cmd: AFU command that experienced the error. + * @scp: SCSI command associated with the AFU command in error. + * + * Translates error bits from AFU command to SCSI command results. + */ +static void process_cmd_err(struct afu_cmd *cmd, struct scsi_cmnd *scp) +{ + struct sisl_ioarcb *ioarcb; + struct sisl_ioasa *ioasa; + + if (unlikely(!cmd)) + return; + + ioarcb = &(cmd->rcb); + ioasa = &(cmd->sa); + + if (ioasa->rc.flags & SISL_RC_FLAGS_UNDERRUN) { + pr_debug("%s: cmd underrun cmd = %p scp = %p\n", + __func__, cmd, scp); + scp->result = (DID_ERROR << 16); + } + + if (ioasa->rc.flags & SISL_RC_FLAGS_OVERRUN) { + pr_debug("%s: cmd underrun cmd = %p scp = %p\n", + __func__, cmd, scp); + scp->result = (DID_ERROR << 16); + } + + pr_debug("%s: cmd failed afu_rc=%d scsi_rc=%d fc_rc=%d " + "afu_extra=0x%X, scsi_entra=0x%X, fc_extra=0x%X\n", + __func__, ioasa->rc.afu_rc, ioasa->rc.scsi_rc, + ioasa->rc.fc_rc, ioasa->afu_extra, ioasa->scsi_extra, + ioasa->fc_extra); + + if (ioasa->rc.scsi_rc) { + /* We have a SCSI status */ + if (ioasa->rc.flags & SISL_RC_FLAGS_SENSE_VALID) { + memcpy(scp->sense_buffer, ioasa->sense_data, + SISL_SENSE_DATA_LEN); + scp->result = ioasa->rc.scsi_rc; + } else + scp->result = ioasa->rc.scsi_rc | (DID_ERROR << 16); + } + + /* + * We encountered an error. Set scp->result based on nature + * of error. + */ + if (ioasa->rc.fc_rc) { + /* We have an FC status */ + switch (ioasa->rc.fc_rc) { + case SISL_FC_RC_LINKDOWN: + scp->result = (DID_REQUEUE << 16); + break; + case SISL_FC_RC_RESID: + /* This indicates an FCP resid underrun */ + if (!(ioasa->rc.flags & SISL_RC_FLAGS_OVERRUN)) { + /* If the SISL_RC_FLAGS_OVERRUN flag was set, + * then we will handle this error else where. + * If not then we must handle it here. + * This is probably an AFU bug. We will + * attempt a retry to see if that resolves it. + */ + scp->result = (DID_ERROR << 16); + } + break; + case SISL_FC_RC_RESIDERR: + /* Resid mismatch between adapter and device */ + case SISL_FC_RC_TGTABORT: + case SISL_FC_RC_ABORTOK: + case SISL_FC_RC_ABORTFAIL: + case SISL_FC_RC_NOLOGI: + case SISL_FC_RC_ABORTPEND: + case SISL_FC_RC_WRABORTPEND: + case SISL_FC_RC_NOEXP: + case SISL_FC_RC_INUSE: + scp->result = (DID_ERROR << 16); + break; + } + } + + if (ioasa->rc.afu_rc) { + /* We have an AFU error */ + switch (ioasa->rc.afu_rc) { + case SISL_AFU_RC_NO_CHANNELS: + scp->result = (DID_MEDIUM_ERROR << 16); + break; + case SISL_AFU_RC_DATA_DMA_ERR: + switch (ioasa->afu_extra) { + case SISL_AFU_DMA_ERR_PAGE_IN: + /* Retry */ + scp->result = (DID_IMM_RETRY << 16); + break; + case SISL_AFU_DMA_ERR_INVALID_EA: + default: + scp->result = (DID_ERROR << 16); + } + break; + case SISL_AFU_RC_OUT_OF_DATA_BUFS: + /* Retry */ + scp->result = (DID_ALLOC_FAILURE << 16); + break; + default: + scp->result = (DID_ERROR << 16); + } + } +} + +/** + * cmd_complete() - command completion handler + * @cmd: AFU command that has completed. + * + * Prepares and submits command that has either completed or timed out to + * the SCSI stack. Checks AFU command back into command pool for non-internal + * (rcb.scp populated) commands. + */ +static void cmd_complete(struct afu_cmd *cmd) +{ + struct scsi_cmnd *scp; + u32 resid; + ulong lock_flags; + struct afu *afu = cmd->parent; + struct cxlflash_cfg *cfg = afu->parent; + bool cmd_is_tmf; + + spin_lock_irqsave(&cmd->slock, lock_flags); + cmd->sa.host_use_b[0] |= B_DONE; + spin_unlock_irqrestore(&cmd->slock, lock_flags); + + if (cmd->rcb.scp) { + scp = cmd->rcb.scp; + if (unlikely(cmd->sa.rc.afu_rc || + cmd->sa.rc.scsi_rc || + cmd->sa.rc.fc_rc)) + process_cmd_err(cmd, scp); + else + scp->result = (DID_OK << 16); + + resid = cmd->sa.resid; + cmd_is_tmf = cmd->cmd_tmf; + cxlflash_cmd_checkin(cmd); /* Don't use cmd after here */ + + pr_debug("%s: calling scsi_set_resid, scp=%p " + "result=%X resid=%d\n", __func__, + scp, scp->result, resid); + + scsi_set_resid(scp, resid); + scsi_dma_unmap(scp); + scp->scsi_done(scp); + + if (cmd_is_tmf) { + spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + cfg->tmf_active = false; + wake_up_all_locked(&cfg->tmf_waitq); + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, + lock_flags); + } + } else + complete(&cmd->cevent); +} + +/** + * send_tmf() - sends a Task Management Function (TMF) + * @afu: AFU to checkout from. + * @scp: SCSI command from stack. + * @tmfcmd: TMF command to send. + * + * Return: + * 0 on success + * SCSI_MLQUEUE_HOST_BUSY when host is busy + */ +static int send_tmf(struct afu *afu, struct scsi_cmnd *scp, u64 tmfcmd) +{ + struct afu_cmd *cmd; + + u32 port_sel = scp->device->channel + 1; + short lflag = 0; + struct Scsi_Host *host = scp->device->host; + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata; + ulong lock_flags; + int rc = 0; + + cmd = cxlflash_cmd_checkout(afu); + if (unlikely(!cmd)) { + pr_err("%s: could not get a free command\n", __func__); + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; + } + + /* If a Task Management Function is active, do not send one more. + */ + spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + if (cfg->tmf_active) + wait_event_interruptible_locked_irq(cfg->tmf_waitq, + !cfg->tmf_active); + cfg->tmf_active = true; + cmd->cmd_tmf = true; + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + + cmd->rcb.ctx_id = afu->ctx_hndl; + cmd->rcb.port_sel = port_sel; + cmd->rcb.lun_id = lun_to_lunid(scp->device->lun); + + lflag = SISL_REQ_FLAGS_TMF_CMD; + + cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID | + SISL_REQ_FLAGS_SUP_UNDERRUN | lflag); + + /* Stash the scp in the reserved field, for reuse during interrupt */ + cmd->rcb.scp = scp; + + /* Copy the CDB from the cmd passed in */ + memcpy(cmd->rcb.cdb, &tmfcmd, sizeof(tmfcmd)); + + /* Send the command */ + rc = cxlflash_send_cmd(afu, cmd); + if (unlikely(rc)) { + cxlflash_cmd_checkin(cmd); + spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + cfg->tmf_active = false; + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + goto out; + } + + spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + wait_event_interruptible_locked_irq(cfg->tmf_waitq, !cfg->tmf_active); + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); +out: + return rc; +} + +/** + * cxlflash_driver_info() - information handler for this host driver + * @host: SCSI host associated with device. + * + * Return: A string describing the device. + */ +static const char *cxlflash_driver_info(struct Scsi_Host *host) +{ + return CXLFLASH_ADAPTER_NAME; +} + +/** + * cxlflash_queuecommand() - sends a mid-layer request + * @host: SCSI host associated with device. + * @scp: SCSI command to send. + * + * Return: + * 0 on success + * SCSI_MLQUEUE_HOST_BUSY when host is busy + */ +static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp) +{ + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata; + struct afu *afu = cfg->afu; + struct pci_dev *pdev = cfg->dev; + struct afu_cmd *cmd; + u32 port_sel = scp->device->channel + 1; + int nseg, i, ncount; + struct scatterlist *sg; + ulong lock_flags; + short lflag = 0; + int rc = 0; + + pr_debug("%s: (scp=%p) %d/%d/%d/%llu cdb=(%08X-%08X-%08X-%08X)\n", + __func__, scp, host->host_no, scp->device->channel, + scp->device->id, scp->device->lun, + get_unaligned_be32(&((u32 *)scp->cmnd)[0]), + get_unaligned_be32(&((u32 *)scp->cmnd)[1]), + get_unaligned_be32(&((u32 *)scp->cmnd)[2]), + get_unaligned_be32(&((u32 *)scp->cmnd)[3])); + + /* If a Task Management Function is active, wait for it to complete + * before continuing with regular commands. + */ + spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + if (cfg->tmf_active) { + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; + } + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + + switch (cfg->state) { + case STATE_LIMBO: + dev_dbg_ratelimited(&cfg->dev->dev, "%s: device in limbo!\n", + __func__); + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; + case STATE_FAILTERM: + dev_dbg_ratelimited(&cfg->dev->dev, "%s: device has failed!\n", + __func__); + scp->result = (DID_NO_CONNECT << 16); + scp->scsi_done(scp); + rc = 0; + goto out; + default: + break; + } + + cmd = cxlflash_cmd_checkout(afu); + if (unlikely(!cmd)) { + pr_err("%s: could not get a free command\n", __func__); + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; + } + + cmd->rcb.ctx_id = afu->ctx_hndl; + cmd->rcb.port_sel = port_sel; + cmd->rcb.lun_id = lun_to_lunid(scp->device->lun); + + if (scp->sc_data_direction == DMA_TO_DEVICE) + lflag = SISL_REQ_FLAGS_HOST_WRITE; + else + lflag = SISL_REQ_FLAGS_HOST_READ; + + cmd->rcb.req_flags = (SISL_REQ_FLAGS_PORT_LUN_ID | + SISL_REQ_FLAGS_SUP_UNDERRUN | lflag); + + /* Stash the scp in the reserved field, for reuse during interrupt */ + cmd->rcb.scp = scp; + + nseg = scsi_dma_map(scp); + if (unlikely(nseg < 0)) { + dev_err(&pdev->dev, "%s: Fail DMA map! nseg=%d\n", + __func__, nseg); + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; + } + + ncount = scsi_sg_count(scp); + scsi_for_each_sg(scp, sg, ncount, i) { + cmd->rcb.data_len = sg_dma_len(sg); + cmd->rcb.data_ea = sg_dma_address(sg); + } + + /* Copy the CDB from the scsi_cmnd passed in */ + memcpy(cmd->rcb.cdb, scp->cmnd, sizeof(cmd->rcb.cdb)); + + /* Send the command */ + rc = cxlflash_send_cmd(afu, cmd); + if (unlikely(rc)) { + cxlflash_cmd_checkin(cmd); + scsi_dma_unmap(scp); + } + +out: + return rc; +} + +/** + * cxlflash_eh_device_reset_handler() - reset a single LUN + * @scp: SCSI command to send. + * + * Return: + * SUCCESS as defined in scsi/scsi.h + * FAILED as defined in scsi/scsi.h + */ +static int cxlflash_eh_device_reset_handler(struct scsi_cmnd *scp) +{ + int rc = SUCCESS; + struct Scsi_Host *host = scp->device->host; + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata; + struct afu *afu = cfg->afu; + int rcr = 0; + + pr_debug("%s: (scp=%p) %d/%d/%d/%llu " + "cdb=(%08X-%08X-%08X-%08X)\n", __func__, scp, + host->host_no, scp->device->channel, + scp->device->id, scp->device->lun, + get_unaligned_be32(&((u32 *)scp->cmnd)[0]), + get_unaligned_be32(&((u32 *)scp->cmnd)[1]), + get_unaligned_be32(&((u32 *)scp->cmnd)[2]), + get_unaligned_be32(&((u32 *)scp->cmnd)[3])); + + switch (cfg->state) { + case STATE_NORMAL: + rcr = send_tmf(afu, scp, TMF_LUN_RESET); + if (unlikely(rcr)) + rc = FAILED; + break; + case STATE_LIMBO: + wait_event(cfg->limbo_waitq, cfg->state != STATE_LIMBO); + if (cfg->state == STATE_NORMAL) + break; + /* fall through */ + default: + rc = FAILED; + break; + } + + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * cxlflash_eh_host_reset_handler() - reset the host adapter + * @scp: SCSI command from stack identifying host. + * + * Return: + * SUCCESS as defined in scsi/scsi.h + * FAILED as defined in scsi/scsi.h + */ +static int cxlflash_eh_host_reset_handler(struct scsi_cmnd *scp) +{ + int rc = SUCCESS; + int rcr = 0; + struct Scsi_Host *host = scp->device->host; + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)host->hostdata; + + pr_debug("%s: (scp=%p) %d/%d/%d/%llu " + "cdb=(%08X-%08X-%08X-%08X)\n", __func__, scp, + host->host_no, scp->device->channel, + scp->device->id, scp->device->lun, + get_unaligned_be32(&((u32 *)scp->cmnd)[0]), + get_unaligned_be32(&((u32 *)scp->cmnd)[1]), + get_unaligned_be32(&((u32 *)scp->cmnd)[2]), + get_unaligned_be32(&((u32 *)scp->cmnd)[3])); + + switch (cfg->state) { + case STATE_NORMAL: + cfg->state = STATE_LIMBO; + scsi_block_requests(cfg->host); + cxlflash_mark_contexts_error(cfg); + rcr = cxlflash_afu_reset(cfg); + if (rcr) { + rc = FAILED; + cfg->state = STATE_FAILTERM; + } else + cfg->state = STATE_NORMAL; + wake_up_all(&cfg->limbo_waitq); + scsi_unblock_requests(cfg->host); + break; + case STATE_LIMBO: + wait_event(cfg->limbo_waitq, cfg->state != STATE_LIMBO); + if (cfg->state == STATE_NORMAL) + break; + /* fall through */ + default: + rc = FAILED; + break; + } + + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * cxlflash_change_queue_depth() - change the queue depth for the device + * @sdev: SCSI device destined for queue depth change. + * @qdepth: Requested queue depth value to set. + * + * The requested queue depth is capped to the maximum supported value. + * + * Return: The actual queue depth set. + */ +static int cxlflash_change_queue_depth(struct scsi_device *sdev, int qdepth) +{ + + if (qdepth > CXLFLASH_MAX_CMDS_PER_LUN) + qdepth = CXLFLASH_MAX_CMDS_PER_LUN; + + scsi_change_queue_depth(sdev, qdepth); + return sdev->queue_depth; +} + +/** + * cxlflash_show_port_status() - queries and presents the current port status + * @dev: Generic device associated with the host owning the port. + * @attr: Device attribute representing the port. + * @buf: Buffer of length PAGE_SIZE to report back port status in ASCII. + * + * Return: The size of the ASCII string returned in @buf. + */ +static ssize_t cxlflash_show_port_status(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata; + struct afu *afu = cfg->afu; + + char *disp_status; + int rc; + u32 port; + u64 status; + u64 *fc_regs; + + rc = kstrtouint((attr->attr.name + 4), 10, &port); + if (rc || (port >= NUM_FC_PORTS)) + return 0; + + fc_regs = &afu->afu_map->global.fc_regs[port][0]; + status = + (readq_be(&fc_regs[FC_MTIP_STATUS / 8]) & FC_MTIP_STATUS_MASK); + + if (status == FC_MTIP_STATUS_ONLINE) + disp_status = "online"; + else if (status == FC_MTIP_STATUS_OFFLINE) + disp_status = "offline"; + else + disp_status = "unknown"; + + return snprintf(buf, PAGE_SIZE, "%s\n", disp_status); +} + +/** + * cxlflash_show_lun_mode() - presents the current LUN mode of the host + * @dev: Generic device associated with the host. + * @attr: Device attribute representing the lun mode. + * @buf: Buffer of length PAGE_SIZE to report back the LUN mode in ASCII. + * + * Return: The size of the ASCII string returned in @buf. + */ +static ssize_t cxlflash_show_lun_mode(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata; + struct afu *afu = cfg->afu; + + return snprintf(buf, PAGE_SIZE, "%u\n", afu->internal_lun); +} + +/** + * cxlflash_store_lun_mode() - sets the LUN mode of the host + * @dev: Generic device associated with the host. + * @attr: Device attribute representing the lun mode. + * @buf: Buffer of length PAGE_SIZE containing the LUN mode in ASCII. + * @count: Length of data resizing in @buf. + * + * The CXL Flash AFU supports a dummy LUN mode where the external + * links and storage are not required. Space on the FPGA is used + * to create 1 or 2 small LUNs which are presented to the system + * as if they were a normal storage device. This feature is useful + * during development and also provides manufacturing with a way + * to test the AFU without an actual device. + * + * 0 = external LUN[s] (default) + * 1 = internal LUN (1 x 64K, 512B blocks, id 0) + * 2 = internal LUN (1 x 64K, 4K blocks, id 0) + * 3 = internal LUN (2 x 32K, 512B blocks, ids 0,1) + * 4 = internal LUN (2 x 32K, 4K blocks, ids 0,1) + * + * Return: The size of the ASCII string returned in @buf. + */ +static ssize_t cxlflash_store_lun_mode(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct Scsi_Host *shost = class_to_shost(dev); + struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)shost->hostdata; + struct afu *afu = cfg->afu; + int rc; + u32 lun_mode; + + rc = kstrtouint(buf, 10, &lun_mode); + if (!rc && (lun_mode < 5) && (lun_mode != afu->internal_lun)) { + afu->internal_lun = lun_mode; + cxlflash_afu_reset(cfg); + scsi_scan_host(cfg->host); + } + + return count; +} + +/** + * cxlflash_show_ioctl_version() - presents the current ioctl version of the host + * @dev: Generic device associated with the host. + * @attr: Device attribute representing the ioctl version. + * @buf: Buffer of length PAGE_SIZE to report back the ioctl version. + * + * Return: The size of the ASCII string returned in @buf. + */ +static ssize_t cxlflash_show_ioctl_version(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return scnprintf(buf, PAGE_SIZE, "%u\n", DK_CXLFLASH_VERSION_0); +} + +/** + * cxlflash_show_dev_mode() - presents the current mode of the device + * @dev: Generic device associated with the device. + * @attr: Device attribute representing the device mode. + * @buf: Buffer of length PAGE_SIZE to report back the dev mode in ASCII. + * + * Return: The size of the ASCII string returned in @buf. + */ +static ssize_t cxlflash_show_dev_mode(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct scsi_device *sdev = to_scsi_device(dev); + + return snprintf(buf, PAGE_SIZE, "%s\n", + sdev->hostdata ? "superpipe" : "legacy"); +} + +/** + * cxlflash_wait_for_pci_err_recovery() - wait for error recovery during probe + * @cxlflash: Internal structure associated with the host. + */ +static void cxlflash_wait_for_pci_err_recovery(struct cxlflash_cfg *cfg) +{ + struct pci_dev *pdev = cfg->dev; + + if (pci_channel_offline(pdev)) + wait_event_timeout(cfg->limbo_waitq, + !pci_channel_offline(pdev), + CXLFLASH_PCI_ERROR_RECOVERY_TIMEOUT); +} + +/* + * Host attributes + */ +static DEVICE_ATTR(port0, S_IRUGO, cxlflash_show_port_status, NULL); +static DEVICE_ATTR(port1, S_IRUGO, cxlflash_show_port_status, NULL); +static DEVICE_ATTR(lun_mode, S_IRUGO | S_IWUSR, cxlflash_show_lun_mode, + cxlflash_store_lun_mode); +static DEVICE_ATTR(ioctl_version, S_IRUGO, cxlflash_show_ioctl_version, NULL); + +static struct device_attribute *cxlflash_host_attrs[] = { + &dev_attr_port0, + &dev_attr_port1, + &dev_attr_lun_mode, + &dev_attr_ioctl_version, + NULL +}; + +/* + * Device attributes + */ +static DEVICE_ATTR(mode, S_IRUGO, cxlflash_show_dev_mode, NULL); + +static struct device_attribute *cxlflash_dev_attrs[] = { + &dev_attr_mode, + NULL +}; + +/* + * Host template + */ +static struct scsi_host_template driver_template = { + .module = THIS_MODULE, + .name = CXLFLASH_ADAPTER_NAME, + .info = cxlflash_driver_info, + .ioctl = cxlflash_ioctl, + .proc_name = CXLFLASH_NAME, + .queuecommand = cxlflash_queuecommand, + .eh_device_reset_handler = cxlflash_eh_device_reset_handler, + .eh_host_reset_handler = cxlflash_eh_host_reset_handler, + .change_queue_depth = cxlflash_change_queue_depth, + .cmd_per_lun = 16, + .can_queue = CXLFLASH_MAX_CMDS, + .this_id = -1, + .sg_tablesize = SG_NONE, /* No scatter gather support. */ + .max_sectors = CXLFLASH_MAX_SECTORS, + .use_clustering = ENABLE_CLUSTERING, + .shost_attrs = cxlflash_host_attrs, + .sdev_attrs = cxlflash_dev_attrs, +}; + +/* + * Device dependent values + */ +static struct dev_dependent_vals dev_corsa_vals = { CXLFLASH_MAX_SECTORS }; + +/* + * PCI device binding table + */ +static struct pci_device_id cxlflash_pci_table[] = { + {PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_CORSA, + PCI_ANY_ID, PCI_ANY_ID, 0, 0, (kernel_ulong_t)&dev_corsa_vals}, + {} +}; + +MODULE_DEVICE_TABLE(pci, cxlflash_pci_table); + +/** + * free_mem() - free memory associated with the AFU + * @cxlflash: Internal structure associated with the host. + */ +static void free_mem(struct cxlflash_cfg *cfg) +{ + int i; + char *buf = NULL; + struct afu *afu = cfg->afu; + + if (cfg->afu) { + for (i = 0; i < CXLFLASH_NUM_CMDS; i++) { + buf = afu->cmd[i].buf; + if (!((u64)buf & (PAGE_SIZE - 1))) + free_page((ulong)buf); + } + + free_pages((ulong)afu, get_order(sizeof(struct afu))); + cfg->afu = NULL; + } +} + +/** + * stop_afu() - stops the AFU command timers and unmaps the MMIO space + * @cxlflash: Internal structure associated with the host. + * + * Safe to call with AFU in a partially allocated/initialized state. + */ +static void stop_afu(struct cxlflash_cfg *cfg) +{ + int i; + struct afu *afu = cfg->afu; + + if (likely(afu)) { + for (i = 0; i < CXLFLASH_NUM_CMDS; i++) + complete(&afu->cmd[i].cevent); + + if (likely(afu->afu_map)) { + cxl_psa_unmap((void *)afu->afu_map); + afu->afu_map = NULL; + } + } +} + +/** + * term_mc() - terminates the master context + * @cxlflash: Internal structure associated with the host. + * @level: Depth of allocation, where to begin waterfall tear down. + * + * Safe to call with AFU/MC in partially allocated/initialized state. + */ +static void term_mc(struct cxlflash_cfg *cfg, enum undo_level level) +{ + int rc = 0; + struct afu *afu = cfg->afu; + + if (!afu || !cfg->mcctx) { + pr_err("%s: returning from term_mc with NULL afu or MC\n", + __func__); + return; + } + + switch (level) { + case UNDO_START: + rc = cxl_stop_context(cfg->mcctx); + BUG_ON(rc); + case UNMAP_THREE: + cxl_unmap_afu_irq(cfg->mcctx, 3, afu); + case UNMAP_TWO: + cxl_unmap_afu_irq(cfg->mcctx, 2, afu); + case UNMAP_ONE: + cxl_unmap_afu_irq(cfg->mcctx, 1, afu); + case FREE_IRQ: + cxl_free_afu_irqs(cfg->mcctx); + case RELEASE_CONTEXT: + cfg->mcctx = NULL; + } +} + +/** + * term_afu() - terminates the AFU + * @cxlflash: Internal structure associated with the host. + * + * Safe to call with AFU/MC in partially allocated/initialized state. + */ +static void term_afu(struct cxlflash_cfg *cfg) +{ + term_mc(cfg, UNDO_START); + + if (cfg->afu) + stop_afu(cfg); + + pr_debug("%s: returning\n", __func__); +} + +/** + * cxlflash_remove() - PCI entry point to tear down host + * @pdev: PCI device associated with the host. + * + * Safe to use as a cleanup in partially allocated/initialized state. + */ +static void cxlflash_remove(struct pci_dev *pdev) +{ + struct cxlflash_cfg *cfg = pci_get_drvdata(pdev); + ulong lock_flags; + + /* If a Task Management Function is active, wait for it to complete + * before continuing with remove. + */ + spin_lock_irqsave(&cfg->tmf_waitq.lock, lock_flags); + if (cfg->tmf_active) + wait_event_interruptible_locked_irq(cfg->tmf_waitq, + !cfg->tmf_active); + spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags); + + cfg->state = STATE_FAILTERM; + cxlflash_stop_term_user_contexts(cfg); + + switch (cfg->init_state) { + case INIT_STATE_SCSI: + cxlflash_term_local_luns(cfg); + scsi_remove_host(cfg->host); + scsi_host_put(cfg->host); + /* Fall through */ + case INIT_STATE_AFU: + term_afu(cfg); + case INIT_STATE_PCI: + pci_release_regions(cfg->dev); + pci_disable_device(pdev); + case INIT_STATE_NONE: + flush_work(&cfg->work_q); + free_mem(cfg); + break; + } + + pr_debug("%s: returning\n", __func__); +} + +/** + * alloc_mem() - allocates the AFU and its command pool + * @cxlflash: Internal structure associated with the host. + * + * A partially allocated state remains on failure. + * + * Return: + * 0 on success + * -ENOMEM on failure to allocate memory + */ +static int alloc_mem(struct cxlflash_cfg *cfg) +{ + int rc = 0; + int i; + char *buf = NULL; + + /* This allocation is about 12K, i.e. only 1 64k page + * and upto 4 4k pages + */ + cfg->afu = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(sizeof(struct afu))); + if (unlikely(!cfg->afu)) { + pr_err("%s: cannot get %d free pages\n", + __func__, get_order(sizeof(struct afu))); + rc = -ENOMEM; + goto out; + } + cfg->afu->parent = cfg; + cfg->afu->afu_map = NULL; + + for (i = 0; i < CXLFLASH_NUM_CMDS; buf += CMD_BUFSIZE, i++) { + if (!((u64)buf & (PAGE_SIZE - 1))) { + buf = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + if (unlikely(!buf)) { + pr_err("%s: Allocate command buffers fail!\n", + __func__); + rc = -ENOMEM; + free_mem(cfg); + goto out; + } + } + + cfg->afu->cmd[i].buf = buf; + atomic_set(&cfg->afu->cmd[i].free, 1); + cfg->afu->cmd[i].slot = i; + } + +out: + return rc; +} + +/** + * init_pci() - initializes the host as a PCI device + * @cxlflash: Internal structure associated with the host. + * + * Return: + * 0 on success + * -EIO on unable to communicate with device + * A return code from the PCI sub-routines + */ +static int init_pci(struct cxlflash_cfg *cfg) +{ + struct pci_dev *pdev = cfg->dev; + int rc = 0; + + cfg->cxlflash_regs_pci = pci_resource_start(pdev, 0); + rc = pci_request_regions(pdev, CXLFLASH_NAME); + if (rc < 0) { + dev_err(&pdev->dev, + "%s: Couldn't register memory range of registers\n", + __func__); + goto out; + } + + rc = pci_enable_device(pdev); + if (rc || pci_channel_offline(pdev)) { + if (pci_channel_offline(pdev)) { + cxlflash_wait_for_pci_err_recovery(cfg); + rc = pci_enable_device(pdev); + } + + if (rc) { + dev_err(&pdev->dev, "%s: Cannot enable adapter\n", + __func__); + cxlflash_wait_for_pci_err_recovery(cfg); + goto out_release_regions; + } + } + + rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64)); + if (rc < 0) { + dev_dbg(&pdev->dev, "%s: Failed to set 64 bit PCI DMA mask\n", + __func__); + rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); + } + + if (rc < 0) { + dev_err(&pdev->dev, "%s: Failed to set PCI DMA mask\n", + __func__); + goto out_disable; + } + + pci_set_master(pdev); + + if (pci_channel_offline(pdev)) { + cxlflash_wait_for_pci_err_recovery(cfg); + if (pci_channel_offline(pdev)) { + rc = -EIO; + goto out_msi_disable; + } + } + + rc = pci_save_state(pdev); + + if (rc != PCIBIOS_SUCCESSFUL) { + dev_err(&pdev->dev, "%s: Failed to save PCI config space\n", + __func__); + rc = -EIO; + goto cleanup_nolog; + } + +out: + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; + +cleanup_nolog: +out_msi_disable: + cxlflash_wait_for_pci_err_recovery(cfg); +out_disable: + pci_disable_device(pdev); +out_release_regions: + pci_release_regions(pdev); + goto out; + +} + +/** + * init_scsi() - adds the host to the SCSI stack and kicks off host scan + * @cxlflash: Internal structure associated with the host. + * + * Return: + * 0 on success + * A return code from adding the host + */ +static int init_scsi(struct cxlflash_cfg *cfg) +{ + struct pci_dev *pdev = cfg->dev; + int rc = 0; + + rc = scsi_add_host(cfg->host, &pdev->dev); + if (rc) { + dev_err(&pdev->dev, "%s: scsi_add_host failed (rc=%d)\n", + __func__, rc); + goto out; + } + + scsi_scan_host(cfg->host); + +out: + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * set_port_online() - transitions the specified host FC port to online state + * @fc_regs: Top of MMIO region defined for specified port. + * + * The provided MMIO region must be mapped prior to call. Online state means + * that the FC link layer has synced, completed the handshaking process, and + * is ready for login to start. + */ +static void set_port_online(u64 *fc_regs) +{ + u64 cmdcfg; + + cmdcfg = readq_be(&fc_regs[FC_MTIP_CMDCONFIG / 8]); + cmdcfg &= (~FC_MTIP_CMDCONFIG_OFFLINE); /* clear OFF_LINE */ + cmdcfg |= (FC_MTIP_CMDCONFIG_ONLINE); /* set ON_LINE */ + writeq_be(cmdcfg, &fc_regs[FC_MTIP_CMDCONFIG / 8]); +} + +/** + * set_port_offline() - transitions the specified host FC port to offline state + * @fc_regs: Top of MMIO region defined for specified port. + * + * The provided MMIO region must be mapped prior to call. + */ +static void set_port_offline(u64 *fc_regs) +{ + u64 cmdcfg; + + cmdcfg = readq_be(&fc_regs[FC_MTIP_CMDCONFIG / 8]); + cmdcfg &= (~FC_MTIP_CMDCONFIG_ONLINE); /* clear ON_LINE */ + cmdcfg |= (FC_MTIP_CMDCONFIG_OFFLINE); /* set OFF_LINE */ + writeq_be(cmdcfg, &fc_regs[FC_MTIP_CMDCONFIG / 8]); +} + +/** + * wait_port_online() - waits for the specified host FC port come online + * @fc_regs: Top of MMIO region defined for specified port. + * @delay_us: Number of microseconds to delay between reading port status. + * @nretry: Number of cycles to retry reading port status. + * + * The provided MMIO region must be mapped prior to call. This will timeout + * when the cable is not plugged in. + * + * Return: + * TRUE (1) when the specified port is online + * FALSE (0) when the specified port fails to come online after timeout + * -EINVAL when @delay_us is less than 1000 + */ +static int wait_port_online(u64 *fc_regs, u32 delay_us, u32 nretry) +{ + u64 status; + + if (delay_us < 1000) { + pr_err("%s: invalid delay specified %d\n", __func__, delay_us); + return -EINVAL; + } + + do { + msleep(delay_us / 1000); + status = readq_be(&fc_regs[FC_MTIP_STATUS / 8]); + } while ((status & FC_MTIP_STATUS_MASK) != FC_MTIP_STATUS_ONLINE && + nretry--); + + return ((status & FC_MTIP_STATUS_MASK) == FC_MTIP_STATUS_ONLINE); +} + +/** + * wait_port_offline() - waits for the specified host FC port go offline + * @fc_regs: Top of MMIO region defined for specified port. + * @delay_us: Number of microseconds to delay between reading port status. + * @nretry: Number of cycles to retry reading port status. + * + * The provided MMIO region must be mapped prior to call. + * + * Return: + * TRUE (1) when the specified port is offline + * FALSE (0) when the specified port fails to go offline after timeout + * -EINVAL when @delay_us is less than 1000 + */ +static int wait_port_offline(u64 *fc_regs, u32 delay_us, u32 nretry) +{ + u64 status; + + if (delay_us < 1000) { + pr_err("%s: invalid delay specified %d\n", __func__, delay_us); + return -EINVAL; + } + + do { + msleep(delay_us / 1000); + status = readq_be(&fc_regs[FC_MTIP_STATUS / 8]); + } while ((status & FC_MTIP_STATUS_MASK) != FC_MTIP_STATUS_OFFLINE && + nretry--); + + return ((status & FC_MTIP_STATUS_MASK) == FC_MTIP_STATUS_OFFLINE); +} + +/** + * afu_set_wwpn() - configures the WWPN for the specified host FC port + * @afu: AFU associated with the host that owns the specified FC port. + * @port: Port number being configured. + * @fc_regs: Top of MMIO region defined for specified port. + * @wwpn: The world-wide-port-number previously discovered for port. + * + * The provided MMIO region must be mapped prior to call. As part of the + * sequence to configure the WWPN, the port is toggled offline and then back + * online. This toggling action can cause this routine to delay up to a few + * seconds. When configured to use the internal LUN feature of the AFU, a + * failure to come online is overridden. + * + * Return: + * 0 when the WWPN is successfully written and the port comes back online + * -1 when the port fails to go offline or come back up online + */ +static int afu_set_wwpn(struct afu *afu, int port, u64 *fc_regs, u64 wwpn) +{ + int ret = 0; + + set_port_offline(fc_regs); + + if (!wait_port_offline(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US, + FC_PORT_STATUS_RETRY_CNT)) { + pr_debug("%s: wait on port %d to go offline timed out\n", + __func__, port); + ret = -1; /* but continue on to leave the port back online */ + } + + if (ret == 0) + writeq_be(wwpn, &fc_regs[FC_PNAME / 8]); + + set_port_online(fc_regs); + + if (!wait_port_online(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US, + FC_PORT_STATUS_RETRY_CNT)) { + pr_debug("%s: wait on port %d to go online timed out\n", + __func__, port); + ret = -1; + + /* + * Override for internal lun!!! + */ + if (afu->internal_lun) { + pr_debug("%s: Overriding port %d online timeout!!!\n", + __func__, port); + ret = 0; + } + } + + pr_debug("%s: returning rc=%d\n", __func__, ret); + + return ret; +} + +/** + * afu_link_reset() - resets the specified host FC port + * @afu: AFU associated with the host that owns the specified FC port. + * @port: Port number being configured. + * @fc_regs: Top of MMIO region defined for specified port. + * + * The provided MMIO region must be mapped prior to call. The sequence to + * reset the port involves toggling it offline and then back online. This + * action can cause this routine to delay up to a few seconds. An effort + * is made to maintain link with the device by switching to host to use + * the alternate port exclusively while the reset takes place. + * failure to come online is overridden. + */ +static void afu_link_reset(struct afu *afu, int port, u64 *fc_regs) +{ + u64 port_sel; + + /* first switch the AFU to the other links, if any */ + port_sel = readq_be(&afu->afu_map->global.regs.afu_port_sel); + port_sel &= ~(1ULL << port); + writeq_be(port_sel, &afu->afu_map->global.regs.afu_port_sel); + cxlflash_afu_sync(afu, 0, 0, AFU_GSYNC); + + set_port_offline(fc_regs); + if (!wait_port_offline(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US, + FC_PORT_STATUS_RETRY_CNT)) + pr_err("%s: wait on port %d to go offline timed out\n", + __func__, port); + + set_port_online(fc_regs); + if (!wait_port_online(fc_regs, FC_PORT_STATUS_RETRY_INTERVAL_US, + FC_PORT_STATUS_RETRY_CNT)) + pr_err("%s: wait on port %d to go online timed out\n", + __func__, port); + + /* switch back to include this port */ + port_sel |= (1ULL << port); + writeq_be(port_sel, &afu->afu_map->global.regs.afu_port_sel); + cxlflash_afu_sync(afu, 0, 0, AFU_GSYNC); + + pr_debug("%s: returning port_sel=%lld\n", __func__, port_sel); +} + +/* + * Asynchronous interrupt information table + */ +static const struct asyc_intr_info ainfo[] = { + {SISL_ASTATUS_FC0_OTHER, "other error", 0, CLR_FC_ERROR | LINK_RESET}, + {SISL_ASTATUS_FC0_LOGO, "target initiated LOGO", 0, 0}, + {SISL_ASTATUS_FC0_CRC_T, "CRC threshold exceeded", 0, LINK_RESET}, + {SISL_ASTATUS_FC0_LOGI_R, "login timed out, retrying", 0, 0}, + {SISL_ASTATUS_FC0_LOGI_F, "login failed", 0, CLR_FC_ERROR}, + {SISL_ASTATUS_FC0_LOGI_S, "login succeeded", 0, 0}, + {SISL_ASTATUS_FC0_LINK_DN, "link down", 0, 0}, + {SISL_ASTATUS_FC0_LINK_UP, "link up", 0, 0}, + {SISL_ASTATUS_FC1_OTHER, "other error", 1, CLR_FC_ERROR | LINK_RESET}, + {SISL_ASTATUS_FC1_LOGO, "target initiated LOGO", 1, 0}, + {SISL_ASTATUS_FC1_CRC_T, "CRC threshold exceeded", 1, LINK_RESET}, + {SISL_ASTATUS_FC1_LOGI_R, "login timed out, retrying", 1, 0}, + {SISL_ASTATUS_FC1_LOGI_F, "login failed", 1, CLR_FC_ERROR}, + {SISL_ASTATUS_FC1_LOGI_S, "login succeeded", 1, 0}, + {SISL_ASTATUS_FC1_LINK_DN, "link down", 1, 0}, + {SISL_ASTATUS_FC1_LINK_UP, "link up", 1, 0}, + {0x0, "", 0, 0} /* terminator */ +}; + +/** + * find_ainfo() - locates and returns asynchronous interrupt information + * @status: Status code set by AFU on error. + * + * Return: The located information or NULL when the status code is invalid. + */ +static const struct asyc_intr_info *find_ainfo(u64 status) +{ + const struct asyc_intr_info *info; + + for (info = &ainfo[0]; info->status; info++) + if (info->status == status) + return info; + + return NULL; +} + +/** + * afu_err_intr_init() - clears and initializes the AFU for error interrupts + * @afu: AFU associated with the host. + */ +static void afu_err_intr_init(struct afu *afu) +{ + int i; + u64 reg; + + /* global async interrupts: AFU clears afu_ctrl on context exit + * if async interrupts were sent to that context. This prevents + * the AFU form sending further async interrupts when + * there is + * nobody to receive them. + */ + + /* mask all */ + writeq_be(-1ULL, &afu->afu_map->global.regs.aintr_mask); + /* set LISN# to send and point to master context */ + reg = ((u64) (((afu->ctx_hndl << 8) | SISL_MSI_ASYNC_ERROR)) << 40); + + if (afu->internal_lun) + reg |= 1; /* Bit 63 indicates local lun */ + writeq_be(reg, &afu->afu_map->global.regs.afu_ctrl); + /* clear all */ + writeq_be(-1ULL, &afu->afu_map->global.regs.aintr_clear); + /* unmask bits that are of interest */ + /* note: afu can send an interrupt after this step */ + writeq_be(SISL_ASTATUS_MASK, &afu->afu_map->global.regs.aintr_mask); + /* clear again in case a bit came on after previous clear but before */ + /* unmask */ + writeq_be(-1ULL, &afu->afu_map->global.regs.aintr_clear); + + /* Clear/Set internal lun bits */ + reg = readq_be(&afu->afu_map->global.fc_regs[0][FC_CONFIG2 / 8]); + reg &= SISL_FC_INTERNAL_MASK; + if (afu->internal_lun) + reg |= ((u64)(afu->internal_lun - 1) << SISL_FC_INTERNAL_SHIFT); + writeq_be(reg, &afu->afu_map->global.fc_regs[0][FC_CONFIG2 / 8]); + + /* now clear FC errors */ + for (i = 0; i < NUM_FC_PORTS; i++) { + writeq_be(0xFFFFFFFFU, + &afu->afu_map->global.fc_regs[i][FC_ERROR / 8]); + writeq_be(0, &afu->afu_map->global.fc_regs[i][FC_ERRCAP / 8]); + } + + /* sync interrupts for master's IOARRIN write */ + /* note that unlike asyncs, there can be no pending sync interrupts */ + /* at this time (this is a fresh context and master has not written */ + /* IOARRIN yet), so there is nothing to clear. */ + + /* set LISN#, it is always sent to the context that wrote IOARRIN */ + writeq_be(SISL_MSI_SYNC_ERROR, &afu->host_map->ctx_ctrl); + writeq_be(SISL_ISTATUS_MASK, &afu->host_map->intr_mask); +} + +/** + * cxlflash_sync_err_irq() - interrupt handler for synchronous errors + * @irq: Interrupt number. + * @data: Private data provided at interrupt registration, the AFU. + * + * Return: Always return IRQ_HANDLED. + */ +static irqreturn_t cxlflash_sync_err_irq(int irq, void *data) +{ + struct afu *afu = (struct afu *)data; + u64 reg; + u64 reg_unmasked; + + reg = readq_be(&afu->host_map->intr_status); + reg_unmasked = (reg & SISL_ISTATUS_UNMASK); + + if (reg_unmasked == 0UL) { + pr_err("%s: %llX: spurious interrupt, intr_status %016llX\n", + __func__, (u64)afu, reg); + goto cxlflash_sync_err_irq_exit; + } + + pr_err("%s: %llX: unexpected interrupt, intr_status %016llX\n", + __func__, (u64)afu, reg); + + writeq_be(reg_unmasked, &afu->host_map->intr_clear); + +cxlflash_sync_err_irq_exit: + pr_debug("%s: returning rc=%d\n", __func__, IRQ_HANDLED); + return IRQ_HANDLED; +} + +/** + * cxlflash_rrq_irq() - interrupt handler for read-response queue (normal path) + * @irq: Interrupt number. + * @data: Private data provided at interrupt registration, the AFU. + * + * Return: Always return IRQ_HANDLED. + */ +static irqreturn_t cxlflash_rrq_irq(int irq, void *data) +{ + struct afu *afu = (struct afu *)data; + struct afu_cmd *cmd; + bool toggle = afu->toggle; + u64 entry, + *hrrq_start = afu->hrrq_start, + *hrrq_end = afu->hrrq_end, + *hrrq_curr = afu->hrrq_curr; + + /* Process however many RRQ entries that are ready */ + while (true) { + entry = *hrrq_curr; + + if ((entry & SISL_RESP_HANDLE_T_BIT) != toggle) + break; + + cmd = (struct afu_cmd *)(entry & ~SISL_RESP_HANDLE_T_BIT); + cmd_complete(cmd); + + /* Advance to next entry or wrap and flip the toggle bit */ + if (hrrq_curr < hrrq_end) + hrrq_curr++; + else { + hrrq_curr = hrrq_start; + toggle ^= SISL_RESP_HANDLE_T_BIT; + } + } + + afu->hrrq_curr = hrrq_curr; + afu->toggle = toggle; + + return IRQ_HANDLED; +} + +/** + * cxlflash_async_err_irq() - interrupt handler for asynchronous errors + * @irq: Interrupt number. + * @data: Private data provided at interrupt registration, the AFU. + * + * Return: Always return IRQ_HANDLED. + */ +static irqreturn_t cxlflash_async_err_irq(int irq, void *data) +{ + struct afu *afu = (struct afu *)data; + struct cxlflash_cfg *cfg; + u64 reg_unmasked; + const struct asyc_intr_info *info; + struct sisl_global_map *global = &afu->afu_map->global; + u64 reg; + u8 port; + int i; + + cfg = afu->parent; + + reg = readq_be(&global->regs.aintr_status); + reg_unmasked = (reg & SISL_ASTATUS_UNMASK); + + if (reg_unmasked == 0) { + pr_err("%s: spurious interrupt, aintr_status 0x%016llX\n", + __func__, reg); + goto out; + } + + /* it is OK to clear AFU status before FC_ERROR */ + writeq_be(reg_unmasked, &global->regs.aintr_clear); + + /* check each bit that is on */ + for (i = 0; reg_unmasked; i++, reg_unmasked = (reg_unmasked >> 1)) { + info = find_ainfo(1ULL << i); + if ((reg_unmasked & 0x1) || !info) + continue; + + port = info->port; + + pr_err("%s: FC Port %d -> %s, fc_status 0x%08llX\n", + __func__, port, info->desc, + readq_be(&global->fc_regs[port][FC_STATUS / 8])); + + /* + * do link reset first, some OTHER errors will set FC_ERROR + * again if cleared before or w/o a reset + */ + if (info->action & LINK_RESET) { + pr_err("%s: FC Port %d: resetting link\n", + __func__, port); + cfg->lr_state = LINK_RESET_REQUIRED; + cfg->lr_port = port; + schedule_work(&cfg->work_q); + } + + if (info->action & CLR_FC_ERROR) { + reg = readq_be(&global->fc_regs[port][FC_ERROR / 8]); + + /* + * since all errors are unmasked, FC_ERROR and FC_ERRCAP + * should be the same and tracing one is sufficient. + */ + + pr_err("%s: fc %d: clearing fc_error 0x%08llX\n", + __func__, port, reg); + + writeq_be(reg, &global->fc_regs[port][FC_ERROR / 8]); + writeq_be(0, &global->fc_regs[port][FC_ERRCAP / 8]); + } + } + +out: + pr_debug("%s: returning rc=%d, afu=%p\n", __func__, IRQ_HANDLED, afu); + return IRQ_HANDLED; +} + +/** + * start_context() - starts the master context + * @cxlflash: Internal structure associated with the host. + * + * Return: A success or failure value from CXL services. + */ +static int start_context(struct cxlflash_cfg *cfg) +{ + int rc = 0; + + rc = cxl_start_context(cfg->mcctx, + cfg->afu->work.work_element_descriptor, + NULL); + + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * read_vpd() - obtains the WWPNs from VPD + * @cxlflash: Internal structure associated with the host. + * @wwpn: Array of size NUM_FC_PORTS to pass back WWPNs + * + * Return: + * 0 on success + * -ENODEV when VPD or WWPN keywords not found + */ +static int read_vpd(struct cxlflash_cfg *cfg, u64 wwpn[]) +{ + struct pci_dev *dev = cfg->parent_dev; + int rc = 0; + int ro_start, ro_size, i, j, k; + ssize_t vpd_size; + char vpd_data[CXLFLASH_VPD_LEN]; + char tmp_buf[WWPN_BUF_LEN] = { 0 }; + char *wwpn_vpd_tags[NUM_FC_PORTS] = { "V5", "V6" }; + + /* Get the VPD data from the device */ + vpd_size = pci_read_vpd(dev, 0, sizeof(vpd_data), vpd_data); + if (unlikely(vpd_size <= 0)) { + pr_err("%s: Unable to read VPD (size = %ld)\n", + __func__, vpd_size); + rc = -ENODEV; + goto out; + } + + /* Get the read only section offset */ + ro_start = pci_vpd_find_tag(vpd_data, 0, vpd_size, + PCI_VPD_LRDT_RO_DATA); + if (unlikely(ro_start < 0)) { + pr_err("%s: VPD Read-only data not found\n", __func__); + rc = -ENODEV; + goto out; + } + + /* Get the read only section size, cap when extends beyond read VPD */ + ro_size = pci_vpd_lrdt_size(&vpd_data[ro_start]); + j = ro_size; + i = ro_start + PCI_VPD_LRDT_TAG_SIZE; + if (unlikely((i + j) > vpd_size)) { + pr_debug("%s: Might need to read more VPD (%d > %ld)\n", + __func__, (i + j), vpd_size); + ro_size = vpd_size - i; + } + + /* + * Find the offset of the WWPN tag within the read only + * VPD data and validate the found field (partials are + * no good to us). Convert the ASCII data to an integer + * value. Note that we must copy to a temporary buffer + * because the conversion service requires that the ASCII + * string be terminated. + */ + for (k = 0; k < NUM_FC_PORTS; k++) { + j = ro_size; + i = ro_start + PCI_VPD_LRDT_TAG_SIZE; + + i = pci_vpd_find_info_keyword(vpd_data, i, j, wwpn_vpd_tags[k]); + if (unlikely(i < 0)) { + pr_err("%s: Port %d WWPN not found in VPD\n", + __func__, k); + rc = -ENODEV; + goto out; + } + + j = pci_vpd_info_field_size(&vpd_data[i]); + i += PCI_VPD_INFO_FLD_HDR_SIZE; + if (unlikely((i + j > vpd_size) || (j != WWPN_LEN))) { + pr_err("%s: Port %d WWPN incomplete or VPD corrupt\n", + __func__, k); + rc = -ENODEV; + goto out; + } + + memcpy(tmp_buf, &vpd_data[i], WWPN_LEN); + rc = kstrtoul(tmp_buf, WWPN_LEN, (ulong *)&wwpn[k]); + if (unlikely(rc)) { + pr_err("%s: Fail to convert port %d WWPN to integer\n", + __func__, k); + rc = -ENODEV; + goto out; + } + } + +out: + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * cxlflash_context_reset() - timeout handler for AFU commands + * @cmd: AFU command that timed out. + * + * Sends a reset to the AFU. + */ +void cxlflash_context_reset(struct afu_cmd *cmd) +{ + int nretry = 0; + u64 rrin = 0x1; + u64 room = 0; + struct afu *afu = cmd->parent; + ulong lock_flags; + + pr_debug("%s: cmd=%p\n", __func__, cmd); + + spin_lock_irqsave(&cmd->slock, lock_flags); + + /* Already completed? */ + if (cmd->sa.host_use_b[0] & B_DONE) { + spin_unlock_irqrestore(&cmd->slock, lock_flags); + return; + } + + cmd->sa.host_use_b[0] |= (B_DONE | B_ERROR | B_TIMEOUT); + spin_unlock_irqrestore(&cmd->slock, lock_flags); + + /* + * We really want to send this reset at all costs, so spread + * out wait time on successive retries for available room. + */ + do { + room = readq_be(&afu->host_map->cmd_room); + atomic64_set(&afu->room, room); + if (room) + goto write_rrin; + udelay(nretry); + } while (nretry++ < MC_ROOM_RETRY_CNT); + + pr_err("%s: no cmd_room to send reset\n", __func__); + return; + +write_rrin: + nretry = 0; + writeq_be(rrin, &afu->host_map->ioarrin); + do { + rrin = readq_be(&afu->host_map->ioarrin); + if (rrin != 0x1) + break; + /* Double delay each time */ + udelay(2 ^ nretry); + } while (nretry++ < MC_ROOM_RETRY_CNT); +} + +/** + * init_pcr() - initialize the provisioning and control registers + * @cxlflash: Internal structure associated with the host. + * + * Also sets up fast access to the mapped registers and initializes AFU + * command fields that never change. + */ +void init_pcr(struct cxlflash_cfg *cfg) +{ + struct afu *afu = cfg->afu; + struct sisl_ctrl_map *ctrl_map; + int i; + + for (i = 0; i < MAX_CONTEXT; i++) { + ctrl_map = &afu->afu_map->ctrls[i].ctrl; + /* disrupt any clients that could be running */ + /* e. g. clients that survived a master restart */ + writeq_be(0, &ctrl_map->rht_start); + writeq_be(0, &ctrl_map->rht_cnt_id); + writeq_be(0, &ctrl_map->ctx_cap); + } + + /* copy frequently used fields into afu */ + afu->ctx_hndl = (u16) cxl_process_element(cfg->mcctx); + /* ctx_hndl is 16 bits in CAIA */ + afu->host_map = &afu->afu_map->hosts[afu->ctx_hndl].host; + afu->ctrl_map = &afu->afu_map->ctrls[afu->ctx_hndl].ctrl; + + /* Program the Endian Control for the master context */ + writeq_be(SISL_ENDIAN_CTRL, &afu->host_map->endian_ctrl); + + /* initialize cmd fields that never change */ + for (i = 0; i < CXLFLASH_NUM_CMDS; i++) { + afu->cmd[i].rcb.ctx_id = afu->ctx_hndl; + afu->cmd[i].rcb.msi = SISL_MSI_RRQ_UPDATED; + afu->cmd[i].rcb.rrq = 0x0; + } +} + +/** + * init_global() - initialize AFU global registers + * @cxlflash: Internal structure associated with the host. + */ +int init_global(struct cxlflash_cfg *cfg) +{ + struct afu *afu = cfg->afu; + u64 wwpn[NUM_FC_PORTS]; /* wwpn of AFU ports */ + int i = 0, num_ports = 0; + int rc = 0; + u64 reg; + + rc = read_vpd(cfg, &wwpn[0]); + if (rc) { + pr_err("%s: could not read vpd rc=%d\n", __func__, rc); + goto out; + } + + pr_debug("%s: wwpn0=0x%llX wwpn1=0x%llX\n", __func__, wwpn[0], wwpn[1]); + + /* set up RRQ in AFU for master issued cmds */ + writeq_be((u64) afu->hrrq_start, &afu->host_map->rrq_start); + writeq_be((u64) afu->hrrq_end, &afu->host_map->rrq_end); + + /* AFU configuration */ + reg = readq_be(&afu->afu_map->global.regs.afu_config); + reg |= SISL_AFUCONF_AR_ALL|SISL_AFUCONF_ENDIAN; + /* enable all auto retry options and control endianness */ + /* leave others at default: */ + /* CTX_CAP write protected, mbox_r does not clear on read and */ + /* checker on if dual afu */ + writeq_be(reg, &afu->afu_map->global.regs.afu_config); + + /* global port select: select either port */ + if (afu->internal_lun) { + /* only use port 0 */ + writeq_be(PORT0, &afu->afu_map->global.regs.afu_port_sel); + num_ports = NUM_FC_PORTS - 1; + } else { + writeq_be(BOTH_PORTS, &afu->afu_map->global.regs.afu_port_sel); + num_ports = NUM_FC_PORTS; + } + + for (i = 0; i < num_ports; i++) { + /* unmask all errors (but they are still masked at AFU) */ + writeq_be(0, &afu->afu_map->global.fc_regs[i][FC_ERRMSK / 8]); + /* clear CRC error cnt & set a threshold */ + (void)readq_be(&afu->afu_map->global. + fc_regs[i][FC_CNT_CRCERR / 8]); + writeq_be(MC_CRC_THRESH, &afu->afu_map->global.fc_regs[i] + [FC_CRC_THRESH / 8]); + + /* set WWPNs. If already programmed, wwpn[i] is 0 */ + if (wwpn[i] != 0 && + afu_set_wwpn(afu, i, + &afu->afu_map->global.fc_regs[i][0], + wwpn[i])) { + pr_err("%s: failed to set WWPN on port %d\n", + __func__, i); + rc = -EIO; + goto out; + } + /* Programming WWPN back to back causes additional + * offline/online transitions and a PLOGI + */ + msleep(100); + + } + + /* set up master's own CTX_CAP to allow real mode, host translation */ + /* tbls, afu cmds and read/write GSCSI cmds. */ + /* First, unlock ctx_cap write by reading mbox */ + (void)readq_be(&afu->ctrl_map->mbox_r); /* unlock ctx_cap */ + writeq_be((SISL_CTX_CAP_REAL_MODE | SISL_CTX_CAP_HOST_XLATE | + SISL_CTX_CAP_READ_CMD | SISL_CTX_CAP_WRITE_CMD | + SISL_CTX_CAP_AFU_CMD | SISL_CTX_CAP_GSCSI_CMD), + &afu->ctrl_map->ctx_cap); + /* init heartbeat */ + afu->hb = readq_be(&afu->afu_map->global.regs.afu_hb); + +out: + return rc; +} + +/** + * start_afu() - initializes and starts the AFU + * @cxlflash: Internal structure associated with the host. + */ +static int start_afu(struct cxlflash_cfg *cfg) +{ + struct afu *afu = cfg->afu; + struct afu_cmd *cmd; + + int i = 0; + int rc = 0; + + for (i = 0; i < CXLFLASH_NUM_CMDS; i++) { + cmd = &afu->cmd[i]; + + init_completion(&cmd->cevent); + spin_lock_init(&cmd->slock); + cmd->parent = afu; + } + + init_pcr(cfg); + + /* initialize RRQ pointers */ + afu->hrrq_start = &afu->rrq_entry[0]; + afu->hrrq_end = &afu->rrq_entry[NUM_RRQ_ENTRY - 1]; + afu->hrrq_curr = afu->hrrq_start; + afu->toggle = 1; + + rc = init_global(cfg); + + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * init_mc() - create and register as the master context + * @cxlflash: Internal structure associated with the host. + * + * Return: + * 0 on success + * -ENOMEM when unable to obtain a context from CXL services + * A failure value from CXL services. + */ +static int init_mc(struct cxlflash_cfg *cfg) +{ + struct cxl_context *ctx; + struct device *dev = &cfg->dev->dev; + struct afu *afu = cfg->afu; + int rc = 0; + enum undo_level level; + + ctx = cxl_get_context(cfg->dev); + if (unlikely(!ctx)) + return -ENOMEM; + cfg->mcctx = ctx; + + /* Set it up as a master with the CXL */ + cxl_set_master(ctx); + + /* During initialization reset the AFU to start from a clean slate */ + rc = cxl_afu_reset(cfg->mcctx); + if (unlikely(rc)) { + dev_err(dev, "%s: initial AFU reset failed rc=%d\n", + __func__, rc); + level = RELEASE_CONTEXT; + goto out; + } + + rc = cxl_allocate_afu_irqs(ctx, 3); + if (unlikely(rc)) { + dev_err(dev, "%s: call to allocate_afu_irqs failed rc=%d!\n", + __func__, rc); + level = RELEASE_CONTEXT; + goto out; + } + + rc = cxl_map_afu_irq(ctx, 1, cxlflash_sync_err_irq, afu, + "SISL_MSI_SYNC_ERROR"); + if (unlikely(rc <= 0)) { + dev_err(dev, "%s: IRQ 1 (SISL_MSI_SYNC_ERROR) map failed!\n", + __func__); + level = FREE_IRQ; + goto out; + } + + rc = cxl_map_afu_irq(ctx, 2, cxlflash_rrq_irq, afu, + "SISL_MSI_RRQ_UPDATED"); + if (unlikely(rc <= 0)) { + dev_err(dev, "%s: IRQ 2 (SISL_MSI_RRQ_UPDATED) map failed!\n", + __func__); + level = UNMAP_ONE; + goto out; + } + + rc = cxl_map_afu_irq(ctx, 3, cxlflash_async_err_irq, afu, + "SISL_MSI_ASYNC_ERROR"); + if (unlikely(rc <= 0)) { + dev_err(dev, "%s: IRQ 3 (SISL_MSI_ASYNC_ERROR) map failed!\n", + __func__); + level = UNMAP_TWO; + goto out; + } + + rc = 0; + + /* This performs the equivalent of the CXL_IOCTL_START_WORK. + * The CXL_IOCTL_GET_PROCESS_ELEMENT is implicit in the process + * element (pe) that is embedded in the context (ctx) + */ + rc = start_context(cfg); + if (unlikely(rc)) { + dev_err(dev, "%s: start context failed rc=%d\n", __func__, rc); + level = UNMAP_THREE; + goto out; + } +ret: + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +out: + term_mc(cfg, level); + goto ret; +} + +/** + * init_afu() - setup as master context and start AFU + * @cxlflash: Internal structure associated with the host. + * + * This routine is a higher level of control for configuring the + * AFU on probe and reset paths. + * + * Return: + * 0 on success + * -ENOMEM when unable to map the AFU MMIO space + * A failure value from internal services. + */ +static int init_afu(struct cxlflash_cfg *cfg) +{ + u64 reg; + int rc = 0; + struct afu *afu = cfg->afu; + struct device *dev = &cfg->dev->dev; + + cxl_perst_reloads_same_image(cfg->cxl_afu, true); + + rc = init_mc(cfg); + if (rc) { + dev_err(dev, "%s: call to init_mc failed, rc=%d!\n", + __func__, rc); + goto err1; + } + + /* Map the entire MMIO space of the AFU. + */ + afu->afu_map = cxl_psa_map(cfg->mcctx); + if (!afu->afu_map) { + rc = -ENOMEM; + term_mc(cfg, UNDO_START); + dev_err(dev, "%s: call to cxl_psa_map failed!\n", __func__); + goto err1; + } + + /* don't byte reverse on reading afu_version, else the string form */ + /* will be backwards */ + reg = afu->afu_map->global.regs.afu_version; + memcpy(afu->version, ®, 8); + afu->interface_version = + readq_be(&afu->afu_map->global.regs.interface_version); + pr_debug("%s: afu version %s, interface version 0x%llX\n", + __func__, afu->version, afu->interface_version); + + rc = start_afu(cfg); + if (rc) { + dev_err(dev, "%s: call to start_afu failed, rc=%d!\n", + __func__, rc); + term_mc(cfg, UNDO_START); + cxl_psa_unmap((void *)afu->afu_map); + afu->afu_map = NULL; + goto err1; + } + + afu_err_intr_init(cfg->afu); + atomic64_set(&afu->room, readq_be(&afu->host_map->cmd_room)); + + /* Restore the LUN mappings */ + cxlflash_restore_luntable(cfg); +err1: + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * cxlflash_send_cmd() - sends an AFU command + * @afu: AFU associated with the host. + * @cmd: AFU command to send. + * + * Return: + * 0 on success + * -1 on failure + */ +int cxlflash_send_cmd(struct afu *afu, struct afu_cmd *cmd) +{ + struct cxlflash_cfg *cfg = afu->parent; + int nretry = 0; + int rc = 0; + u64 room; + long newval; + + /* + * This routine is used by critical users such an AFU sync and to + * send a task management function (TMF). Thus we want to retry a + * bit before returning an error. To avoid the performance penalty + * of MMIO, we spread the update of 'room' over multiple commands. + */ +retry: + newval = atomic64_dec_if_positive(&afu->room); + if (!newval) { + do { + room = readq_be(&afu->host_map->cmd_room); + atomic64_set(&afu->room, room); + if (room) + goto write_ioarrin; + udelay(nretry); + } while (nretry++ < MC_ROOM_RETRY_CNT); + + pr_err("%s: no cmd_room to send 0x%X\n", + __func__, cmd->rcb.cdb[0]); + + goto no_room; + } else if (unlikely(newval < 0)) { + /* This should be rare. i.e. Only if two threads race and + * decrement before the MMIO read is done. In this case + * just benefit from the other thread having updated + * afu->room. + */ + if (nretry++ < MC_ROOM_RETRY_CNT) { + udelay(nretry); + goto retry; + } + + goto no_room; + } + +write_ioarrin: + writeq_be((u64)&cmd->rcb, &afu->host_map->ioarrin); +out: + pr_debug("%s: cmd=%p len=%d ea=%p rc=%d\n", __func__, cmd, + cmd->rcb.data_len, (void *)cmd->rcb.data_ea, rc); + return rc; + +no_room: + afu->read_room = true; + schedule_work(&cfg->work_q); + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; +} + +/** + * cxlflash_wait_resp() - polls for a response or timeout to a sent AFU command + * @afu: AFU associated with the host. + * @cmd: AFU command that was sent. + */ +void cxlflash_wait_resp(struct afu *afu, struct afu_cmd *cmd) +{ + ulong timeout = jiffies + (cmd->rcb.timeout * 2 * HZ); + + timeout = wait_for_completion_timeout(&cmd->cevent, timeout); + if (!timeout) + cxlflash_context_reset(cmd); + + if (unlikely(cmd->sa.ioasc != 0)) + pr_err("%s: CMD 0x%X failed, IOASC: flags 0x%X, afu_rc 0x%X, " + "scsi_rc 0x%X, fc_rc 0x%X\n", __func__, cmd->rcb.cdb[0], + cmd->sa.rc.flags, cmd->sa.rc.afu_rc, cmd->sa.rc.scsi_rc, + cmd->sa.rc.fc_rc); +} + +/** + * cxlflash_afu_sync() - builds and sends an AFU sync command + * @afu: AFU associated with the host. + * @ctx_hndl_u: Identifies context requesting sync. + * @res_hndl_u: Identifies resource requesting sync. + * @mode: Type of sync to issue (lightweight, heavyweight, global). + * + * The AFU can only take 1 sync command at a time. This routine enforces this + * limitation by using a mutex to provide exlusive access to the AFU during + * the sync. This design point requires calling threads to not be on interrupt + * context due to the possibility of sleeping during concurrent sync operations. + * + * AFU sync operations are only necessary and allowed when the device is + * operating normally. When not operating normally, sync requests can occur as + * part of cleaning up resources associated with an adapter prior to removal. + * In this scenario, these requests are simply ignored (safe due to the AFU + * going away). + * + * Return: + * 0 on success + * -1 on failure + */ +int cxlflash_afu_sync(struct afu *afu, ctx_hndl_t ctx_hndl_u, + res_hndl_t res_hndl_u, u8 mode) +{ + struct cxlflash_cfg *cfg = afu->parent; + struct afu_cmd *cmd = NULL; + int rc = 0; + int retry_cnt = 0; + static DEFINE_MUTEX(sync_active); + + if (cfg->state != STATE_NORMAL) { + pr_debug("%s: Sync not required! (%u)\n", __func__, cfg->state); + return 0; + } + + mutex_lock(&sync_active); +retry: + cmd = cxlflash_cmd_checkout(afu); + if (unlikely(!cmd)) { + retry_cnt++; + udelay(1000 * retry_cnt); + if (retry_cnt < MC_RETRY_CNT) + goto retry; + pr_err("%s: could not get a free command\n", __func__); + rc = -1; + goto out; + } + + pr_debug("%s: afu=%p cmd=%p %d\n", __func__, afu, cmd, ctx_hndl_u); + + memset(cmd->rcb.cdb, 0, sizeof(cmd->rcb.cdb)); + + cmd->rcb.req_flags = SISL_REQ_FLAGS_AFU_CMD; + cmd->rcb.port_sel = 0x0; /* NA */ + cmd->rcb.lun_id = 0x0; /* NA */ + cmd->rcb.data_len = 0x0; + cmd->rcb.data_ea = 0x0; + cmd->rcb.timeout = MC_AFU_SYNC_TIMEOUT; + + cmd->rcb.cdb[0] = 0xC0; /* AFU Sync */ + cmd->rcb.cdb[1] = mode; + + /* The cdb is aligned, no unaligned accessors required */ + *((u16 *)&cmd->rcb.cdb[2]) = swab16(ctx_hndl_u); + *((u32 *)&cmd->rcb.cdb[4]) = swab32(res_hndl_u); + + rc = cxlflash_send_cmd(afu, cmd); + if (unlikely(rc)) + goto out; + + cxlflash_wait_resp(afu, cmd); + + /* set on timeout */ + if (unlikely((cmd->sa.ioasc != 0) || + (cmd->sa.host_use_b[0] & B_ERROR))) + rc = -1; +out: + mutex_unlock(&sync_active); + if (cmd) + cxlflash_cmd_checkin(cmd); + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * cxlflash_afu_reset() - resets the AFU + * @cxlflash: Internal structure associated with the host. + * + * Return: + * 0 on success + * A failure value from internal services. + */ +int cxlflash_afu_reset(struct cxlflash_cfg *cfg) +{ + int rc = 0; + /* Stop the context before the reset. Since the context is + * no longer available restart it after the reset is complete + */ + + term_afu(cfg); + + rc = init_afu(cfg); + + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; +} + +/** + * cxlflash_worker_thread() - work thread handler for the AFU + * @work: Work structure contained within cxlflash associated with host. + * + * Handles the following events: + * - Link reset which cannot be performed on interrupt context due to + * blocking up to a few seconds + * - Read AFU command room + */ +static void cxlflash_worker_thread(struct work_struct *work) +{ + struct cxlflash_cfg *cfg = container_of(work, struct cxlflash_cfg, + work_q); + struct afu *afu = cfg->afu; + int port; + ulong lock_flags; + + /* Avoid MMIO if the device has failed */ + + if (cfg->state != STATE_NORMAL) + return; + + spin_lock_irqsave(cfg->host->host_lock, lock_flags); + + if (cfg->lr_state == LINK_RESET_REQUIRED) { + port = cfg->lr_port; + if (port < 0) + pr_err("%s: invalid port index %d\n", __func__, port); + else { + spin_unlock_irqrestore(cfg->host->host_lock, + lock_flags); + + /* The reset can block... */ + afu_link_reset(afu, port, + &afu->afu_map-> + global.fc_regs[port][0]); + spin_lock_irqsave(cfg->host->host_lock, lock_flags); + } + + cfg->lr_state = LINK_RESET_COMPLETE; + } + + if (afu->read_room) { + atomic64_set(&afu->room, readq_be(&afu->host_map->cmd_room)); + afu->read_room = false; + } + + spin_unlock_irqrestore(cfg->host->host_lock, lock_flags); +} + +/** + * cxlflash_probe() - PCI entry point to add host + * @pdev: PCI device associated with the host. + * @dev_id: PCI device id associated with device. + * + * Return: 0 on success / non-zero on failure + */ +static int cxlflash_probe(struct pci_dev *pdev, + const struct pci_device_id *dev_id) +{ + struct Scsi_Host *host; + struct cxlflash_cfg *cfg = NULL; + struct device *phys_dev; + struct dev_dependent_vals *ddv; + int rc = 0; + + dev_dbg(&pdev->dev, "%s: Found CXLFLASH with IRQ: %d\n", + __func__, pdev->irq); + + ddv = (struct dev_dependent_vals *)dev_id->driver_data; + driver_template.max_sectors = ddv->max_sectors; + + host = scsi_host_alloc(&driver_template, sizeof(struct cxlflash_cfg)); + if (!host) { + dev_err(&pdev->dev, "%s: call to scsi_host_alloc failed!\n", + __func__); + rc = -ENOMEM; + goto out; + } + + host->max_id = CXLFLASH_MAX_NUM_TARGETS_PER_BUS; + host->max_lun = CXLFLASH_MAX_NUM_LUNS_PER_TARGET; + host->max_channel = NUM_FC_PORTS - 1; + host->unique_id = host->host_no; + host->max_cmd_len = CXLFLASH_MAX_CDB_LEN; + + cfg = (struct cxlflash_cfg *)host->hostdata; + cfg->host = host; + rc = alloc_mem(cfg); + if (rc) { + dev_err(&pdev->dev, "%s: call to scsi_host_alloc failed!\n", + __func__); + rc = -ENOMEM; + goto out; + } + + cfg->init_state = INIT_STATE_NONE; + cfg->dev = pdev; + + /* + * The promoted LUNs move to the top of the LUN table. The rest stay + * on the bottom half. The bottom half grows from the end + * (index = 255), whereas the top half grows from the beginning + * (index = 0). + */ + cfg->promote_lun_index = 0; + cfg->last_lun_index[0] = CXLFLASH_NUM_VLUNS/2 - 1; + cfg->last_lun_index[1] = CXLFLASH_NUM_VLUNS/2 - 1; + + cfg->dev_id = (struct pci_device_id *)dev_id; + cfg->mcctx = NULL; + + init_waitqueue_head(&cfg->tmf_waitq); + init_waitqueue_head(&cfg->limbo_waitq); + + INIT_WORK(&cfg->work_q, cxlflash_worker_thread); + cfg->lr_state = LINK_RESET_INVALID; + cfg->lr_port = -1; + mutex_init(&cfg->ctx_tbl_list_mutex); + mutex_init(&cfg->ctx_recovery_mutex); + INIT_LIST_HEAD(&cfg->ctx_err_recovery); + INIT_LIST_HEAD(&cfg->lluns); + + pci_set_drvdata(pdev, cfg); + + /* Use the special service provided to look up the physical + * PCI device, since we are called on the probe of the virtual + * PCI host bus (vphb) + */ + phys_dev = cxl_get_phys_dev(pdev); + if (!dev_is_pci(phys_dev)) { + pr_err("%s: not a pci dev\n", __func__); + rc = -ENODEV; + goto out_remove; + } + cfg->parent_dev = to_pci_dev(phys_dev); + + cfg->cxl_afu = cxl_pci_to_afu(pdev); + + rc = init_pci(cfg); + if (rc) { + dev_err(&pdev->dev, "%s: call to init_pci " + "failed rc=%d!\n", __func__, rc); + goto out_remove; + } + cfg->init_state = INIT_STATE_PCI; + + rc = init_afu(cfg); + if (rc) { + dev_err(&pdev->dev, "%s: call to init_afu " + "failed rc=%d!\n", __func__, rc); + goto out_remove; + } + cfg->init_state = INIT_STATE_AFU; + + + rc = init_scsi(cfg); + if (rc) { + dev_err(&pdev->dev, "%s: call to init_scsi " + "failed rc=%d!\n", __func__, rc); + goto out_remove; + } + cfg->init_state = INIT_STATE_SCSI; + +out: + pr_debug("%s: returning rc=%d\n", __func__, rc); + return rc; + +out_remove: + cxlflash_remove(pdev); + goto out; +} + +/** + * cxlflash_pci_error_detected() - called when a PCI error is detected + * @pdev: PCI device struct. + * @state: PCI channel state. + * + * Return: PCI_ERS_RESULT_NEED_RESET or PCI_ERS_RESULT_DISCONNECT + */ +static pci_ers_result_t cxlflash_pci_error_detected(struct pci_dev *pdev, + pci_channel_state_t state) +{ + int rc = 0; + struct cxlflash_cfg *cfg = pci_get_drvdata(pdev); + struct device *dev = &cfg->dev->dev; + + dev_dbg(dev, "%s: pdev=%p state=%u\n", __func__, pdev, state); + + switch (state) { + case pci_channel_io_frozen: + cfg->state = STATE_LIMBO; + + /* Turn off legacy I/O */ + scsi_block_requests(cfg->host); + rc = cxlflash_mark_contexts_error(cfg); + if (unlikely(rc)) + dev_err(dev, "%s: Failed to mark user contexts!(%d)\n", + __func__, rc); + term_mc(cfg, UNDO_START); + stop_afu(cfg); + + return PCI_ERS_RESULT_NEED_RESET; + case pci_channel_io_perm_failure: + cfg->state = STATE_FAILTERM; + wake_up_all(&cfg->limbo_waitq); + scsi_unblock_requests(cfg->host); + return PCI_ERS_RESULT_DISCONNECT; + default: + break; + } + return PCI_ERS_RESULT_NEED_RESET; +} + +/** + * cxlflash_pci_slot_reset() - called when PCI slot has been reset + * @pdev: PCI device struct. + * + * This routine is called by the pci error recovery code after the PCI + * slot has been reset, just before we should resume normal operations. + * + * Return: PCI_ERS_RESULT_RECOVERED or PCI_ERS_RESULT_DISCONNECT + */ +static pci_ers_result_t cxlflash_pci_slot_reset(struct pci_dev *pdev) +{ + int rc = 0; + struct cxlflash_cfg *cfg = pci_get_drvdata(pdev); + struct device *dev = &cfg->dev->dev; + + dev_dbg(dev, "%s: pdev=%p\n", __func__, pdev); + + rc = init_afu(cfg); + if (unlikely(rc)) { + dev_err(dev, "%s: EEH recovery failed! (%d)\n", __func__, rc); + return PCI_ERS_RESULT_DISCONNECT; + } + + return PCI_ERS_RESULT_RECOVERED; +} + +/** + * cxlflash_pci_resume() - called when normal operation can resume + * @pdev: PCI device struct + */ +static void cxlflash_pci_resume(struct pci_dev *pdev) +{ + struct cxlflash_cfg *cfg = pci_get_drvdata(pdev); + struct device *dev = &cfg->dev->dev; + + dev_dbg(dev, "%s: pdev=%p\n", __func__, pdev); + + cfg->state = STATE_NORMAL; + wake_up_all(&cfg->limbo_waitq); + scsi_unblock_requests(cfg->host); +} + +static const struct pci_error_handlers cxlflash_err_handler = { + .error_detected = cxlflash_pci_error_detected, + .slot_reset = cxlflash_pci_slot_reset, + .resume = cxlflash_pci_resume, +}; + +/* + * PCI device structure + */ +static struct pci_driver cxlflash_driver = { + .name = CXLFLASH_NAME, + .id_table = cxlflash_pci_table, + .probe = cxlflash_probe, + .remove = cxlflash_remove, + .err_handler = &cxlflash_err_handler, +}; + +/** + * init_cxlflash() - module entry point + * + * Return: 0 on success / non-zero on failure + */ +static int __init init_cxlflash(void) +{ + pr_info("%s: IBM Power CXL Flash Adapter: %s\n", + __func__, CXLFLASH_DRIVER_DATE); + + cxlflash_list_init(); + + return pci_register_driver(&cxlflash_driver); +} + +/** + * exit_cxlflash() - module exit point + */ +static void __exit exit_cxlflash(void) +{ + cxlflash_term_global_luns(); + cxlflash_free_errpage(); + + pci_unregister_driver(&cxlflash_driver); +} + +module_init(init_cxlflash); +module_exit(exit_cxlflash); |