dmaengine: bcm-sba-raid: Increase number of free sba_request

Currently, we have only 1024 free sba_request created
by sba_prealloc_channel_resources(). This is too low
and the prep_xxx() callbacks start failing more often
at time of RAID array setup over NVMe disks.

This patch sets number of free sba_request created by
sba_prealloc_channel_resources() to be:
<number_of_mailbox_channels> x 8192

Due to above, we will have sufficient number of free
sba_request and prep_xxx() callbacks failing is very
unlikely.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c
index 9ab2d95..4c68509 100644 (file)
--- a/drivers/dma/bcm-sba-raid.c
+++ b/drivers/dma/bcm-sba-raid.c
@@ -83,6 +83,8 @@
 #define SBA_CMD_WRITE_BUFFER                           0xc
 #define SBA_CMD_GALOIS                                 0xe
 
+#define SBA_MAX_REQ_PER_MBOX_CHANNEL                   8192
+
 /* Driver helper macros */
 #define to_sba_request(tx)             \
        container_of(tx, struct sba_request, tx)
@@ -1622,6 +1624,13 @@ static int sba_probe(struct platform_device *pdev)
        sba->dev = &pdev->dev;
        platform_set_drvdata(pdev, sba);
 
+       /* Number of channels equals number of mailbox channels */
+       ret = of_count_phandle_with_args(pdev->dev.of_node,
+                                        "mboxes", "#mbox-cells");
+       if (ret <= 0)
+               return -ENODEV;
+       mchans_count = ret;
+
        /* Determine SBA version from DT compatible string */
        if (of_device_is_compatible(sba->dev->of_node, "brcm,iproc-sba"))
                sba->ver = SBA_VER_1;
@@ -1634,14 +1643,12 @@ static int sba_probe(struct platform_device *pdev)
        /* Derived Configuration parameters */
        switch (sba->ver) {
        case SBA_VER_1:
-               sba->max_req = 1024;
                sba->hw_buf_size = 4096;
                sba->hw_resp_size = 8;
                sba->max_pq_coefs = 6;
                sba->max_pq_srcs = 6;
                break;
        case SBA_VER_2:
-               sba->max_req = 1024;
                sba->hw_buf_size = 4096;
                sba->hw_resp_size = 8;
                sba->max_pq_coefs = 30;
@@ -1655,6 +1662,7 @@ static int sba_probe(struct platform_device *pdev)
        default:
                return -EINVAL;
        }
+       sba->max_req = SBA_MAX_REQ_PER_MBOX_CHANNEL * mchans_count;
        sba->max_cmd_per_req = sba->max_pq_srcs + 3;
        sba->max_xor_srcs = sba->max_cmd_per_req - 1;
        sba->max_resp_pool_size = sba->max_req * sba->hw_resp_size;
@@ -1668,22 +1676,14 @@ static int sba_probe(struct platform_device *pdev)
        sba->client.knows_txdone        = false;
        sba->client.tx_tout             = 0;
 
-       /* Number of channels equals number of mailbox channels */
-       ret = of_count_phandle_with_args(pdev->dev.of_node,
-                                        "mboxes", "#mbox-cells");
-       if (ret <= 0)
-               return -ENODEV;
-       mchans_count = ret;
-       sba->mchans_count = 0;
-       atomic_set(&sba->mchans_current, 0);
-
        /* Allocate mailbox channel array */
-       sba->mchans = devm_kcalloc(&pdev->dev, sba->mchans_count,
+       sba->mchans = devm_kcalloc(&pdev->dev, mchans_count,
                                   sizeof(*sba->mchans), GFP_KERNEL);
        if (!sba->mchans)
                return -ENOMEM;
 
        /* Request mailbox channels */
+       sba->mchans_count = 0;
        for (i = 0; i < mchans_count; i++) {
                sba->mchans[i] = mbox_request_channel(&sba->client, i);
                if (IS_ERR(sba->mchans[i])) {
@@ -1692,6 +1692,7 @@ static int sba_probe(struct platform_device *pdev)
                }
                sba->mchans_count++;
        }
+       atomic_set(&sba->mchans_current, 0);
 
        /* Find-out underlying mailbox device */
        ret = of_parse_phandle_with_args(pdev->dev.of_node,