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linux/drivers/scsi/cxlflash/main.c

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/*
* 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");
/**
* 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.
*/
static struct afu_cmd *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_devel("%s: returning found index=%d cmd=%p\n",
__func__, cmd->slot, cmd);
memset(cmd->buf, 0, CMD_BUFSIZE);
memset(cmd->rcb.cdb, 0, sizeof(cmd->rcb.cdb));
return cmd;
}
}
return NULL;
}
/**
* 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.
*/
static void 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_devel("%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;
u32 resid;
if (unlikely(!cmd))
return;
ioarcb = &(cmd->rcb);
ioasa = &(cmd->sa);
if (ioasa->rc.flags & SISL_RC_FLAGS_UNDERRUN) {
resid = ioasa->resid;
scsi_set_resid(scp, resid);
pr_debug("%s: cmd underrun cmd = %p scp = %p, resid = %d\n",
__func__, cmd, scp, resid);
}
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_extra=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.
*/
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_NO_CONNECT << 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;
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.ioasc))
process_cmd_err(cmd, scp);
else
scp->result = (DID_OK << 16);
cmd_is_tmf = cmd->cmd_tmf;
cmd_checkin(cmd); /* Don't use cmd after here */
pr_debug_ratelimited("%s: calling scsi_done scp=%p result=%X "
"ioasc=%d\n", __func__, scp, scp->result,
cmd->sa.ioasc);
scsi_dma_unmap(scp);
scp->scsi_done(scp);
if (cmd_is_tmf) {
spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
cfg->tmf_active = false;
wake_up_all_locked(&cfg->tmf_waitq);
spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags);
}
} else
complete(&cmd->cevent);
}
/**
* context_reset() - timeout handler for AFU commands
* @cmd: AFU command that timed out.
*
* Sends a reset to the AFU.
*/
static void 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);
}
/**
* send_cmd() - sends an AFU command
* @afu: AFU associated with the host.
* @cmd: AFU command to send.
*
* Return:
* 0 on success, SCSI_MLQUEUE_HOST_BUSY on failure
*/
static int send_cmd(struct afu *afu, struct afu_cmd *cmd)
{
struct cxlflash_cfg *cfg = afu->parent;
struct device *dev = &cfg->dev->dev;
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);
dev_err(dev, "%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_devel("%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;
}
/**
* 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.
*/
static void wait_resp(struct afu *afu, struct afu_cmd *cmd)
{
ulong timeout = msecs_to_jiffies(cmd->rcb.timeout * 2 * 1000);
timeout = wait_for_completion_timeout(&cmd->cevent, timeout);
if (!timeout)
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);
}
/**
* 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 on failure
*/
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;
struct device *dev = &cfg->dev->dev;
ulong lock_flags;
int rc = 0;
ulong to;
cmd = cmd_checkout(afu);
if (unlikely(!cmd)) {
dev_err(dev, "%s: could not get a free command\n", __func__);
rc = SCSI_MLQUEUE_HOST_BUSY;
goto out;
}
/* When Task Management Function is active do not send another */
spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
if (cfg->tmf_active)
wait_event_interruptible_lock_irq(cfg->tmf_waitq,
!cfg->tmf_active,
cfg->tmf_slock);
cfg->tmf_active = true;
cmd->cmd_tmf = true;
spin_unlock_irqrestore(&cfg->tmf_slock, 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 = send_cmd(afu, cmd);
if (unlikely(rc)) {
cmd_checkin(cmd);
spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
cfg->tmf_active = false;
spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags);
goto out;
}
spin_lock_irqsave(&cfg->tmf_slock, lock_flags);
to = msecs_to_jiffies(5000);
to = wait_event_interruptible_lock_irq_timeout(cfg->tmf_waitq,
!cfg->tmf_active,
cfg->tmf_slock,
to);
if (!to) {
cfg->tmf_active = false;
dev_err(dev, "%s: TMF timed out!\n", __func__);
rc = -1;
}
spin_unlock_irqrestore(&cfg->tmf_slock, 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 on failure
*/
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 device *dev = &cfg->dev->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;
dev_dbg_ratelimited(dev, "%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_slock, lock_flags);
if (cfg->tmf_active) {
spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags);
rc = SCSI_MLQUEUE_HOST_BUSY;
goto out;
}
spin_unlock_irqrestore(&cfg->tmf_slock, lock_flags);
switch (cfg->state) {
case STATE_RESET:
dev_dbg_ratelimited(dev, "%s: device is in reset!\n", __func__);
rc = SCSI_MLQUEUE_HOST_BUSY;
goto out;
case STATE_FAILTERM:
dev_dbg_ratelimited(dev, "%s: device has failed!\n", __func__);
scp->result = (DID_NO_CONNECT << 16);
scp->scsi_done(scp);
rc = 0;
goto out;
default:
break;
}
cmd = cmd_checkout(afu);
if (unlikely(!cmd)) {
dev_err(dev, "%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(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 = send_cmd(afu, cmd);
if (unlikely(rc)) {
cmd_checkin(cmd);
scsi_dma_unmap(scp);
}
out:
pr_devel("%s: returning rc=%d\n", __func__, rc);
return rc;
}
/**
* cxlflash_wait_for_pci_err_recovery() - wait for error recovery during probe
* @cfg: 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->reset_waitq,
!pci_channel_offline(pdev),
CXLFLASH_PCI_ERROR_RECOVERY_TIMEOUT);
}
/**
* free_mem() - free memory associated with the AFU
* @cfg: 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
* @cfg: 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 __iomem *)afu->afu_map);
afu->afu_map = NULL;
}
}
}
/**
* term_mc() - terminates the master context
* @cfg: 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;
struct device *dev = &cfg->dev->dev;
if (!afu || !cfg->mcctx) {
dev_err(dev, "%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
* @cfg: 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_slock, lock_flags);
if (cfg->tmf_active)
wait_event_interruptible_lock_irq(cfg->tmf_waitq,
!cfg->tmf_active,
cfg->tmf_slock);
spin_unlock_irqrestore(&cfg->tmf_slock, 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);
/* fall through */
case INIT_STATE_AFU:
term_afu(cfg);
cancel_work_sync(&cfg->work_q);
case INIT_STATE_PCI:
pci_release_regions(cfg->dev);
pci_disable_device(pdev);
case INIT_STATE_NONE:
free_mem(cfg);
scsi_host_put(cfg->host);
break;
}
pr_debug("%s: returning\n", __func__);
}
/**
* alloc_mem() - allocates the AFU and its command pool
* @cfg: 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;
struct device *dev = &cfg->dev->dev;
/* AFU is ~12k, i.e. only one 64k page or up to four 4k pages */
cfg->afu = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
get_order(sizeof(struct afu)));
if (unlikely(!cfg->afu)) {
dev_err(dev, "%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)) {
dev_err(dev,
"%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
* @cfg: Internal structure associated with the host.
*
* Return: 0 on success, -errno on failure
*/
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
* @cfg: Internal structure associated with the host.
*
* Return: 0 on success, -errno on failure
*/
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(__be64 __iomem *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(__be64 __iomem *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(__be64 __iomem *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(__be64 __iomem *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, __be64 __iomem *fc_regs,
u64 wwpn)
{
int rc = 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);
rc = -1; /* but continue on to leave the port back online */
}
if (rc == 0)
writeq_be(wwpn, &fc_regs[FC_PNAME / 8]);
/* Always return success after programming WWPN */
rc = 0;
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);
}
pr_debug("%s: returning rc=%d\n", __func__, rc);
return rc;
}
/**
* 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, __be64 __iomem *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, LINK_RESET},
{SISL_ASTATUS_FC0_LOGI_F, "login failed", 0, CLR_FC_ERROR},
{SISL_ASTATUS_FC0_LOGI_S, "login succeeded", 0, SCAN_HOST},
{SISL_ASTATUS_FC0_LINK_DN, "link down", 0, 0},
{SISL_ASTATUS_FC0_LINK_UP, "link up", 0, SCAN_HOST},
{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, SCAN_HOST},
{SISL_ASTATUS_FC1_LINK_DN, "link down", 1, 0},
{SISL_ASTATUS_FC1_LINK_UP, "link up", 1, SCAN_HOST},
{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 = afu->parent;
struct device *dev = &cfg->dev->dev;
u64 reg_unmasked;
const struct asyc_intr_info *info;
struct sisl_global_map __iomem *global = &afu->afu_map->global;
u64 reg;
u8 port;
int i;
reg = readq_be(&global->regs.aintr_status);
reg_unmasked = (reg & SISL_ASTATUS_UNMASK);
if (reg_unmasked == 0) {
dev_err(dev, "%s: spurious interrupt, aintr_status 0x%016llX\n",
__func__, reg);
goto out;
}
/* FYI, it is 'okay' 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) == 0) || !info)
continue;
port = info->port;
dev_err(dev, "%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) {
dev_err(dev, "%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.
*/
dev_err(dev, "%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]);
}
if (info->action & SCAN_HOST) {
atomic_inc(&cfg->scan_host_needed);
schedule_work(&cfg->work_q);
}
}
out:
dev_dbg(dev, "%s: returning IRQ_HANDLED, afu=%p\n", __func__, afu);
return IRQ_HANDLED;
}
/**
* start_context() - starts the master context
* @cfg: 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
* @cfg: Internal structure associated with the host.
* @wwpn: Array of size NUM_FC_PORTS to pass back WWPNs
*
* Return: 0 on success, -errno on failure
*/
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)) {
dev_err(&dev->dev, "%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)) {
dev_err(&dev->dev, "%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)) {
dev_err(&dev->dev, "%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))) {
dev_err(&dev->dev, "%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)) {
dev_err(&dev->dev, "%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;
}
/**
* init_pcr() - initialize the provisioning and control registers
* @cfg: Internal structure associated with the host.
*
* Also sets up fast access to the mapped registers and initializes AFU
* command fields that never change.
*/
static void init_pcr(struct cxlflash_cfg *cfg)
{
struct afu *afu = cfg->afu;
struct sisl_ctrl_map __iomem *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);
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
* @cfg: Internal structure associated with the host.
*/
static int init_global(struct cxlflash_cfg *cfg)
{
struct afu *afu = cfg->afu;
struct device *dev = &cfg->dev->dev;
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) {
dev_err(dev, "%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])) {
dev_err(dev, "%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 */
/* tables, 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);
/* Initialize heartbeat */
afu->hb = readq_be(&afu->afu_map->global.regs.afu_hb);
out:
return rc;
}
/**
* start_afu() - initializes and starts the AFU
* @cfg: 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);
/* After an AFU reset, RRQ entries are stale, clear them */
memset(&afu->rrq_entry, 0, sizeof(afu->rrq_entry));
/* 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
* @cfg: Internal structure associated with the host.
*
* Return: 0 on success, -errno on failure
*/
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
* @cfg: 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, -errno on failure
*/
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 out;
}
/* Map the entire MMIO space of the AFU */
afu->afu_map = cxl_psa_map(cfg->mcctx);
if (!afu->afu_map) {
dev_err(dev, "%s: call to cxl_psa_map failed!\n", __func__);
rc = -ENOMEM;
goto err1;
}
/* No byte reverse on reading afu_version or string will be backwards */
reg = readq(&afu->afu_map->global.regs.afu_version);
memcpy(afu->version, &reg, sizeof(reg));
afu->interface_version =
readq_be(&afu->afu_map->global.regs.interface_version);
if ((afu->interface_version + 1) == 0) {
pr_err("Back level AFU, please upgrade. AFU version %s "
"interface version 0x%llx\n", afu->version,
afu->interface_version);
rc = -EINVAL;
goto err2;
}
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);
goto err2;
}
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);
out:
pr_debug("%s: returning rc=%d\n", __func__, rc);
return rc;
err2:
cxl_psa_unmap((void __iomem *)afu->afu_map);
afu->afu_map = NULL;
err1:
term_mc(cfg, UNDO_START);
goto out;
}
/**
* 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 exclusive 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 device *dev = &cfg->dev->dev;
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 = cmd_checkout(afu);
if (unlikely(!cmd)) {
retry_cnt++;
udelay(1000 * retry_cnt);
if (retry_cnt < MC_RETRY_CNT)
goto retry;
dev_err(dev, "%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 */
*((__be16 *)&cmd->rcb.cdb[2]) = cpu_to_be16(ctx_hndl_u);
*((__be32 *)&cmd->rcb.cdb[4]) = cpu_to_be32(res_hndl_u);
rc = send_cmd(afu, cmd);
if (unlikely(rc))
goto out;
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)
cmd_checkin(cmd);
pr_debug("%s: returning rc=%d\n", __func__, rc);
return rc;
}
/**
* afu_reset() - resets the AFU
* @cfg: Internal structure associated with the host.
*
* Return: 0 on success, -errno on failure
*/
static int 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_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]));
retry:
switch (cfg->state) {
case STATE_NORMAL:
rcr = send_tmf(afu, scp, TMF_LUN_RESET);
if (unlikely(rcr))
rc = FAILED;
break;
case STATE_RESET:
wait_event(cfg->reset_waitq, cfg->state != STATE_RESET);
goto retry;
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_RESET;
cxlflash_mark_contexts_error(cfg);
rcr = afu_reset(cfg);
if (rcr) {
rc = FAILED;
cfg->state = STATE_FAILTERM;
} else
cfg->state = STATE_NORMAL;
wake_up_all(&cfg->reset_waitq);
break;
case STATE_RESET:
wait_event(cfg->reset_waitq, cfg->state != STATE_RESET);
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
* @port: Desired port for status reporting.
* @afu: AFU owning the specified 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(u32 port, struct afu *afu, char *buf)
{
char *disp_status;
u64 status;
__be64 __iomem *fc_regs;
if (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]);
status &= 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 scnprintf(buf, PAGE_SIZE, "%s\n", disp_status);
}
/**
* port0_show() - queries and presents the current status of port 0
* @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 port0_show(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 cxlflash_show_port_status(0, afu, buf);
}
/**
* port1_show() - queries and presents the current status of port 1
* @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 port1_show(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 cxlflash_show_port_status(1, afu, buf);
}
/**
* lun_mode_show() - 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 lun_mode_show(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 scnprintf(buf, PAGE_SIZE, "%u\n", afu->internal_lun);
}
/**
* lun_mode_store() - 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 lun_mode_store(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;
afu_reset(cfg);
scsi_scan_host(cfg->host);
}
return count;
}
/**
* ioctl_version_show() - 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 ioctl_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return scnprintf(buf, PAGE_SIZE, "%u\n", DK_CXLFLASH_VERSION_0);
}
/**
* cxlflash_show_port_lun_table() - queries and presents the port LUN table
* @port: Desired port for status reporting.
* @afu: AFU owning the specified 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_lun_table(u32 port,
struct afu *afu,
char *buf)
{
int i;
ssize_t bytes = 0;
__be64 __iomem *fc_port;
if (port >= NUM_FC_PORTS)
return 0;
fc_port = &afu->afu_map->global.fc_port[port][0];
for (i = 0; i < CXLFLASH_NUM_VLUNS; i++)
bytes += scnprintf(buf + bytes, PAGE_SIZE - bytes,
"%03d: %016llX\n", i, readq_be(&fc_port[i]));
return bytes;
}
/**
* port0_lun_table_show() - presents the current LUN table of port 0
* @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 port0_lun_table_show(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 cxlflash_show_port_lun_table(0, afu, buf);
}
/**
* port1_lun_table_show() - presents the current LUN table of port 1
* @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 port1_lun_table_show(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 cxlflash_show_port_lun_table(1, afu, buf);
}
/**
* mode_show() - 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 mode_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct scsi_device *sdev = to_scsi_device(dev);
return scnprintf(buf, PAGE_SIZE, "%s\n",
sdev->hostdata ? "superpipe" : "legacy");
}
/*
* Host attributes
*/
static DEVICE_ATTR_RO(port0);
static DEVICE_ATTR_RO(port1);
static DEVICE_ATTR_RW(lun_mode);
static DEVICE_ATTR_RO(ioctl_version);
static DEVICE_ATTR_RO(port0_lun_table);
static DEVICE_ATTR_RO(port1_lun_table);
static struct device_attribute *cxlflash_host_attrs[] = {
&dev_attr_port0,
&dev_attr_port1,
&dev_attr_lun_mode,
&dev_attr_ioctl_version,
&dev_attr_port0_lun_table,
&dev_attr_port1_lun_table,
NULL
};
/*
* Device attributes
*/
static DEVICE_ATTR_RO(mode);
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);
/**
* 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
* - Rescan the host
*/
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;
struct device *dev = &cfg->dev->dev;
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)
dev_err(dev, "%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);
if (atomic_dec_if_positive(&cfg->scan_host_needed) >= 0)
scsi_scan_host(cfg->host);
}
/**
* 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, -errno 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 alloc_mem failed!\n",
__func__);
rc = -ENOMEM;
scsi_host_put(cfg->host);
goto out;
}
cfg->init_state = INIT_STATE_NONE;
cfg->dev = pdev;
cfg->cxl_fops = cxlflash_cxl_fops;
/*
* 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;
init_waitqueue_head(&cfg->tmf_waitq);
init_waitqueue_head(&cfg->reset_waitq);
INIT_WORK(&cfg->work_q, cxlflash_worker_thread);
cfg->lr_state = LINK_RESET_INVALID;
cfg->lr_port = -1;
spin_lock_init(&cfg->tmf_slock);
mutex_init(&cfg->ctx_tbl_list_mutex);
mutex_init(&cfg->ctx_recovery_mutex);
init_rwsem(&cfg->ioctl_rwsem);
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)) {
dev_err(&pdev->dev, "%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;
}
/**
* drain_ioctls() - wait until all currently executing ioctls have completed
* @cfg: Internal structure associated with the host.
*
* Obtain write access to read/write semaphore that wraps ioctl
* handling to 'drain' ioctls currently executing.
*/
static void drain_ioctls(struct cxlflash_cfg *cfg)
{
down_write(&cfg->ioctl_rwsem);
up_write(&cfg->ioctl_rwsem);
}
/**
* 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_RESET;
scsi_block_requests(cfg->host);
drain_ioctls(cfg);
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->reset_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->reset_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, -errno 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);
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