[SCSI] stex: add support for reset request from firmware

Add support for reset request from firmware for controllers
of st_shasta and st_yel type. Code adjustments necessary
for this change are also included.

Signed-off-by: Ed Lin <ed.lin@promise.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 166 insertions, 83 deletions

diff --git a/drivers/scsi/stex.c b/drivers/scsi/stex.c
index af5bafcccf1f..79216ee8112b 100644
--- a/drivers/scsi/stex.c
+++ b/drivers/scsi/stex.c
@@ -64,24 +64,24 @@ enum {
         YH2I_REQ_HI                             = 0xc4,
 
         /* MU register value */
-        MU_INBOUND_DOORBELL_HANDSHAKE           = 1,
-        MU_INBOUND_DOORBELL_REQHEADCHANGED      = 2,
-        MU_INBOUND_DOORBELL_STATUSTAILCHANGED   = 4,
-        MU_INBOUND_DOORBELL_HMUSTOPPED          = 8,
-        MU_INBOUND_DOORBELL_RESET               = 16,
-
-        MU_OUTBOUND_DOORBELL_HANDSHAKE          = 1,
-        MU_OUTBOUND_DOORBELL_REQUESTTAILCHANGED = 2,
-        MU_OUTBOUND_DOORBELL_STATUSHEADCHANGED  = 4,
-        MU_OUTBOUND_DOORBELL_BUSCHANGE          = 8,
-        MU_OUTBOUND_DOORBELL_HASEVENT           = 16,
+        MU_INBOUND_DOORBELL_HANDSHAKE           = (1 << 0),
+        MU_INBOUND_DOORBELL_REQHEADCHANGED      = (1 << 1),
+        MU_INBOUND_DOORBELL_STATUSTAILCHANGED   = (1 << 2),
+        MU_INBOUND_DOORBELL_HMUSTOPPED          = (1 << 3),
+        MU_INBOUND_DOORBELL_RESET               = (1 << 4),
+
+        MU_OUTBOUND_DOORBELL_HANDSHAKE          = (1 << 0),
+        MU_OUTBOUND_DOORBELL_REQUESTTAILCHANGED = (1 << 1),
+        MU_OUTBOUND_DOORBELL_STATUSHEADCHANGED  = (1 << 2),
+        MU_OUTBOUND_DOORBELL_BUSCHANGE          = (1 << 3),
+        MU_OUTBOUND_DOORBELL_HASEVENT           = (1 << 4),
+        MU_OUTBOUND_DOORBELL_REQUEST_RESET      = (1 << 27),
 
         /* MU status code */
         MU_STATE_STARTING                       = 1,
-        MU_STATE_FMU_READY_FOR_HANDSHAKE        = 2,
-        MU_STATE_SEND_HANDSHAKE_FRAME           = 3,
-        MU_STATE_STARTED                        = 4,
-        MU_STATE_RESETTING                      = 5,
+        MU_STATE_STARTED                        = 2,
+        MU_STATE_RESETTING                      = 3,
+        MU_STATE_FAILED                         = 4,
 
         MU_MAX_DELAY                            = 120,
         MU_HANDSHAKE_SIGNATURE                  = 0x55aaaa55,
@@ -111,6 +111,8 @@ enum {
 
         SS_H2I_INT_RESET                        = 0x100,
 
+        SS_I2H_REQUEST_RESET                    = 0x2000,
+
         SS_MU_OPERATIONAL                       = 0x80000000,
 
         STEX_CDB_LENGTH                         = 16,
@@ -312,6 +314,10 @@ struct st_hba {
         struct st_ccb *wait_ccb;
         __le32 *scratch;
 
+        char work_q_name[20];
+        struct workqueue_struct *work_q;
+        struct work_struct reset_work;
+        wait_queue_head_t reset_waitq;
         unsigned int mu_status;
         unsigned int cardtype;
         int msi_enabled;
@@ -578,6 +584,9 @@ stex_queuecommand(struct scsi_cmnd *cmd, void (* done)(struct scsi_cmnd *))
         lun = cmd->device->lun;
         hba = (struct st_hba *) &host->hostdata[0];
 
+        if (unlikely(hba->mu_status == MU_STATE_RESETTING))
+                return SCSI_MLQUEUE_HOST_BUSY;
+
         switch (cmd->cmnd[0]) {
         case MODE_SENSE_10:
         {
@@ -842,7 +851,6 @@ static irqreturn_t stex_intr(int irq, void *__hba)
         void __iomem *base = hba->mmio_base;
         u32 data;
         unsigned long flags;
-        int handled = 0;
 
         spin_lock_irqsave(hba->host->host_lock, flags);
 
@@ -853,12 +861,16 @@ static irqreturn_t stex_intr(int irq, void *__hba)
                 writel(data, base + ODBL);
                 readl(base + ODBL); /* flush */
                 stex_mu_intr(hba, data);
-                handled = 1;
+                spin_unlock_irqrestore(hba->host->host_lock, flags);
+                if (unlikely(data & MU_OUTBOUND_DOORBELL_REQUEST_RESET &&
+                        hba->cardtype == st_shasta))
+                        queue_work(hba->work_q, &hba->reset_work);
+                return IRQ_HANDLED;
         }
 
         spin_unlock_irqrestore(hba->host->host_lock, flags);
 
-        return IRQ_RETVAL(handled);
+        return IRQ_NONE;
 }
 
 static void stex_ss_mu_intr(struct st_hba *hba)
@@ -940,7 +952,6 @@ static irqreturn_t stex_ss_intr(int irq, void *__hba)
         void __iomem *base = hba->mmio_base;
         u32 data;
         unsigned long flags;
-        int handled = 0;
 
         spin_lock_irqsave(hba->host->host_lock, flags);
 
@@ -949,12 +960,15 @@ static irqreturn_t stex_ss_intr(int irq, void *__hba)
                 /* clear the interrupt */
                 writel(data, base + YI2H_INT_C);
                 stex_ss_mu_intr(hba);
-                handled = 1;
+                spin_unlock_irqrestore(hba->host->host_lock, flags);
+                if (unlikely(data & SS_I2H_REQUEST_RESET))
+                        queue_work(hba->work_q, &hba->reset_work);
+                return IRQ_HANDLED;
         }
 
         spin_unlock_irqrestore(hba->host->host_lock, flags);
 
-        return IRQ_RETVAL(handled);
+        return IRQ_NONE;
 }
 
 static int stex_common_handshake(struct st_hba *hba)
@@ -1047,7 +1061,7 @@ static int stex_ss_handshake(struct st_hba *hba)
         struct st_msg_header *msg_h;
         struct handshake_frame *h;
         __le32 *scratch;
-        u32 data;
+        u32 data, scratch_size;
         unsigned long before;
         int ret = 0;
 
@@ -1075,13 +1089,16 @@ static int stex_ss_handshake(struct st_hba *hba)
         stex_gettime(&h->hosttime);
         h->partner_type = HMU_PARTNER_TYPE;
         h->extra_offset = h->extra_size = 0;
-        h->scratch_size = cpu_to_le32((hba->sts_count+1)*sizeof(u32));
+        scratch_size = (hba->sts_count+1)*sizeof(u32);
+        h->scratch_size = cpu_to_le32(scratch_size);
 
         data = readl(base + YINT_EN);
         data &= ~4;
         writel(data, base + YINT_EN);
         writel((hba->dma_handle >> 16) >> 16, base + YH2I_REQ_HI);
+        readl(base + YH2I_REQ_HI);
         writel(hba->dma_handle, base + YH2I_REQ);
+        readl(base + YH2I_REQ); /* flush */
 
         scratch = hba->scratch;
         before = jiffies;
@@ -1097,7 +1114,7 @@ static int stex_ss_handshake(struct st_hba *hba)
                 msleep(1);
         }
 
-        *scratch = 0;
+        memset(scratch, 0, scratch_size);
         msg_h->flag = 0;
         return ret;
 }
@@ -1106,19 +1123,24 @@ static int stex_handshake(struct st_hba *hba)
 {
         int err;
         unsigned long flags;
+        unsigned int mu_status;
 
         err = (hba->cardtype == st_yel) ?
                 stex_ss_handshake(hba) : stex_common_handshake(hba);
+        spin_lock_irqsave(hba->host->host_lock, flags);
+        mu_status = hba->mu_status;
         if (err == 0) {
-                spin_lock_irqsave(hba->host->host_lock, flags);
                 hba->req_head = 0;
                 hba->req_tail = 0;
                 hba->status_head = 0;
                 hba->status_tail = 0;
                 hba->out_req_cnt = 0;
                 hba->mu_status = MU_STATE_STARTED;
-                spin_unlock_irqrestore(hba->host->host_lock, flags);
-        }
+        } else
+                hba->mu_status = MU_STATE_FAILED;
+        if (mu_status == MU_STATE_RESETTING)
+                wake_up_all(&hba->reset_waitq);
+        spin_unlock_irqrestore(hba->host->host_lock, flags);
         return err;
 }
 
@@ -1138,17 +1160,11 @@ static int stex_abort(struct scsi_cmnd *cmd)
 
         base = hba->mmio_base;
         spin_lock_irqsave(host->host_lock, flags);
-        if (tag < host->can_queue && hba->ccb[tag].cmd == cmd)
+        if (tag < host->can_queue &&
+                hba->ccb[tag].req && hba->ccb[tag].cmd == cmd)
                 hba->wait_ccb = &hba->ccb[tag];
-        else {
-                for (tag = 0; tag < host->can_queue; tag++)
-                        if (hba->ccb[tag].cmd == cmd) {
-                                hba->wait_ccb = &hba->ccb[tag];
-                                break;
-                        }
-                if (tag >= host->can_queue)
-                        goto out;
-        }
+        else
+                goto out;
 
         if (hba->cardtype == st_yel) {
                 data = readl(base + YI2H_INT);
@@ -1222,6 +1238,37 @@ static void stex_hard_reset(struct st_hba *hba)
                         hba->pdev->saved_config_space[i]);
 }
 
+static int stex_yos_reset(struct st_hba *hba)
+{
+        void __iomem *base;
+        unsigned long flags, before;
+        int ret = 0;
+
+        base = hba->mmio_base;
+        writel(MU_INBOUND_DOORBELL_RESET, base + IDBL);
+        readl(base + IDBL); /* flush */
+        before = jiffies;
+        while (hba->out_req_cnt > 0) {
+                if (time_after(jiffies, before + ST_INTERNAL_TIMEOUT * HZ)) {
+                        printk(KERN_WARNING DRV_NAME
+                                "(%s): reset timeout\n", pci_name(hba->pdev));
+                        ret = -1;
+                        break;
+                }
+                msleep(1);
+        }
+
+        spin_lock_irqsave(hba->host->host_lock, flags);
+        if (ret == -1)
+                hba->mu_status = MU_STATE_FAILED;
+        else
+                hba->mu_status = MU_STATE_STARTED;
+        wake_up_all(&hba->reset_waitq);
+        spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+        return ret;
+}
+
 static void stex_ss_reset(struct st_hba *hba)
 {
         writel(SS_H2I_INT_RESET, hba->mmio_base + YH2I_INT);
@@ -1229,66 +1276,86 @@ static void stex_ss_reset(struct st_hba *hba)
         ssleep(5);
 }
 
-static int stex_reset(struct scsi_cmnd *cmd)
+static int stex_do_reset(struct st_hba *hba)
 {
-        struct st_hba *hba;
-        void __iomem *base;
-        unsigned long flags, before;
+        struct st_ccb *ccb;
+        unsigned long flags;
+        unsigned int mu_status = MU_STATE_RESETTING;
+        u16 tag;
 
-        hba = (struct st_hba *) &cmd->device->host->hostdata[0];
+        spin_lock_irqsave(hba->host->host_lock, flags);
+        if (hba->mu_status == MU_STATE_STARTING) {
+                spin_unlock_irqrestore(hba->host->host_lock, flags);
+                printk(KERN_INFO DRV_NAME "(%s): request reset during init\n",
+                        pci_name(hba->pdev));
+                return 0;
+        }
+        while (hba->mu_status == MU_STATE_RESETTING) {
+                spin_unlock_irqrestore(hba->host->host_lock, flags);
+                wait_event_timeout(hba->reset_waitq,
+                                   hba->mu_status != MU_STATE_RESETTING,
+                                   MU_MAX_DELAY * HZ);
+                spin_lock_irqsave(hba->host->host_lock, flags);
+                mu_status = hba->mu_status;
+        }
 
-        printk(KERN_INFO DRV_NAME
-                "(%s): resetting host\n", pci_name(hba->pdev));
-        scsi_print_command(cmd);
+        if (mu_status != MU_STATE_RESETTING) {
+                spin_unlock_irqrestore(hba->host->host_lock, flags);
+                return (mu_status == MU_STATE_STARTED) ? 0 : -1;
+        }
 
         hba->mu_status = MU_STATE_RESETTING;
+        spin_unlock_irqrestore(hba->host->host_lock, flags);
+
+        if (hba->cardtype == st_yosemite)
+                return stex_yos_reset(hba);
 
         if (hba->cardtype == st_shasta)
                 stex_hard_reset(hba);
         else if (hba->cardtype == st_yel)
                 stex_ss_reset(hba);
 
-        if (hba->cardtype != st_yosemite) {
-                if (stex_handshake(hba)) {
-                        printk(KERN_WARNING DRV_NAME
-                                "(%s): resetting: handshake failed\n",
-                                pci_name(hba->pdev));
-                        return FAILED;
+        spin_lock_irqsave(hba->host->host_lock, flags);
+        for (tag = 0; tag < hba->host->can_queue; tag++) {
+                ccb = &hba->ccb[tag];
+                if (ccb->req == NULL)
+                        continue;
+                ccb->req = NULL;
+                if (ccb->cmd) {
+                        scsi_dma_unmap(ccb->cmd);
+                        ccb->cmd->result = DID_RESET << 16;
+                        ccb->cmd->scsi_done(ccb->cmd);
+                        ccb->cmd = NULL;
                 }
-                return SUCCESS;
         }
+        spin_unlock_irqrestore(hba->host->host_lock, flags);
 
-        /* st_yosemite */
-        writel(MU_INBOUND_DOORBELL_RESET, hba->mmio_base + IDBL);
-        readl(hba->mmio_base + IDBL); /* flush */
-        before = jiffies;
-        while (hba->out_req_cnt > 0) {
-                if (time_after(jiffies, before + ST_INTERNAL_TIMEOUT * HZ)) {
-                        printk(KERN_WARNING DRV_NAME
-                                "(%s): reset timeout\n", pci_name(hba->pdev));
-                        return FAILED;
-                }
-                msleep(1);
-        }
+        if (stex_handshake(hba) == 0)
+                return 0;
 
-        base = hba->mmio_base;
-        writel(0, base + IMR0);
-        readl(base + IMR0);
-        writel(0, base + OMR0);
-        readl(base + OMR0);
-        writel(0, base + IMR1);
-        readl(base + IMR1);
-        writel(0, base + OMR1);
-        readl(base + OMR1); /* flush */
-        spin_lock_irqsave(hba->host->host_lock, flags);
-        hba->req_head = 0;
-        hba->req_tail = 0;
-        hba->status_head = 0;
-        hba->status_tail = 0;
-        hba->out_req_cnt = 0;
-        hba->mu_status = MU_STATE_STARTED;
-        spin_unlock_irqrestore(hba->host->host_lock, flags);
-        return SUCCESS;
+        printk(KERN_WARNING DRV_NAME "(%s): resetting: handshake failed\n",
+                pci_name(hba->pdev));
+        return -1;
+}
+
+static int stex_reset(struct scsi_cmnd *cmd)
+{
+        struct st_hba *hba;
+
+        hba = (struct st_hba *) &cmd->device->host->hostdata[0];
+
+        printk(KERN_INFO DRV_NAME
+                "(%s): resetting host\n", pci_name(hba->pdev));
+        scsi_print_command(cmd);
+
+        return stex_do_reset(hba) ? FAILED : SUCCESS;
+}
+
+static void stex_reset_work(struct work_struct *work)
+{
+        struct st_hba *hba = container_of(work, struct st_hba, reset_work);
+
+        stex_do_reset(hba);
 }
 
 static int stex_biosparam(struct scsi_device *sdev,
@@ -1583,12 +1650,24 @@ stex_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
         hba->host = host;
         hba->pdev = pdev;
+        init_waitqueue_head(&hba->reset_waitq);
+
+        snprintf(hba->work_q_name, sizeof(hba->work_q_name),
+                 "stex_wq_%d", host->host_no);
+        hba->work_q = create_singlethread_workqueue(hba->work_q_name);
+        if (!hba->work_q) {
+                printk(KERN_ERR DRV_NAME "(%s): create workqueue failed\n",
+                        pci_name(pdev));
+                err = -ENOMEM;
+                goto out_ccb_free;
+        }
+        INIT_WORK(&hba->reset_work, stex_reset_work);
 
         err = stex_request_irq(hba);
         if (err) {
                 printk(KERN_ERR DRV_NAME "(%s): request irq failed\n",
                         pci_name(pdev));
-                goto out_ccb_free;
+                goto out_free_wq;
         }
 
         err = stex_handshake(hba);
@@ -1617,6 +1696,8 @@ stex_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 out_free_irq:
         stex_free_irq(hba);
+out_free_wq:
+        destroy_workqueue(hba->work_q);
 out_ccb_free:
         kfree(hba->ccb);
 out_pci_free:
@@ -1684,6 +1765,8 @@ static void stex_hba_free(struct st_hba *hba)
 {
         stex_free_irq(hba);
 
+        destroy_workqueue(hba->work_q);
+
         iounmap(hba->mmio_base);
 
         pci_release_regions(hba->pdev);