i40e: fix u64 division usage

Commit 52eb1ff93e98 ("i40e: Add support setting TC max bandwidth rates")
and commit 1ea6f21ae530 ("i40e: Refactor VF BW rate limiting") add some
needed functionality for TC bandwidth rate limiting.  Unfortunately they
introduce several usages of unsigned 64-bit division which needs to be
handled special by the kernel to support all architectures.

Fixes: 52eb1ff93e98 ("i40e: Add support setting TC max bandwidth
rates")
Fixes: 1ea6f21ae530 ("i40e: Refactor VF BW rate limiting")

Signed-off-by: Alan Brady <alan.brady@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

diff --git a/drivers/net/ethernet/intel/i40e/i40e.h b/drivers/net/ethernet/intel/i40e/i40e.h
index 266e1dc..eb01776 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e.h
+++ b/drivers/net/ethernet/intel/i40e/i40e.h
@@ -130,7 +130,8 @@
 
 /* BW rate limiting */
 #define I40E_BW_CREDIT_DIVISOR         50 /* 50Mbps per BW credit */
-#define I40E_MAX_BW_INACTIVE_ACCUM     4  /* accumulate 4 credits max */
+#define I40E_BW_MBPS_DIVISOR           125000 /* rate / (1000000 / 8) Mbps */
+#define I40E_MAX_BW_INACTIVE_ACCUM     4 /* accumulate 4 credits max */
 
 /* driver state flags */
 enum i40e_state_t {

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index bb31d53..1252aaf 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -5442,6 +5442,7 @@ int i40e_get_link_speed(struct i40e_vsi *vsi)
 int i40e_set_bw_limit(struct i40e_vsi *vsi, u16 seid, u64 max_tx_rate)
 {
        struct i40e_pf *pf = vsi->back;
+       u64 credits = 0;
        int speed = 0;
        int ret = 0;
 
@@ -5459,8 +5460,9 @@ int i40e_set_bw_limit(struct i40e_vsi *vsi, u16 seid, u64 max_tx_rate)
        }
 
        /* Tx rate credits are in values of 50Mbps, 0 is disabled */
-       ret = i40e_aq_config_vsi_bw_limit(&pf->hw, seid,
-                                         max_tx_rate / I40E_BW_CREDIT_DIVISOR,
+       credits = max_tx_rate;
+       do_div(credits, I40E_BW_CREDIT_DIVISOR);
+       ret = i40e_aq_config_vsi_bw_limit(&pf->hw, seid, credits,
                                          I40E_MAX_BW_INACTIVE_ACCUM, NULL);
        if (ret)
                dev_err(&pf->pdev->dev,
@@ -6063,13 +6065,17 @@ int i40e_create_queue_channel(struct i40e_vsi *vsi,
 
        /* configure VSI for BW limit */
        if (ch->max_tx_rate) {
+               u64 credits = ch->max_tx_rate;
+
                if (i40e_set_bw_limit(vsi, ch->seid, ch->max_tx_rate))
                        return -EINVAL;
 
+               do_div(credits, I40E_BW_CREDIT_DIVISOR);
                dev_dbg(&pf->pdev->dev,
                        "Set tx rate of %llu Mbps (count of 50Mbps %llu) for vsi->seid %u\n",
                        ch->max_tx_rate,
-                       ch->max_tx_rate / I40E_BW_CREDIT_DIVISOR, ch->seid);
+                       credits,
+                       ch->seid);
        }
 
        /* in case of VF, this will be main SRIOV VSI */
@@ -6090,6 +6096,7 @@ int i40e_create_queue_channel(struct i40e_vsi *vsi,
 static int i40e_configure_queue_channels(struct i40e_vsi *vsi)
 {
        struct i40e_channel *ch;
+       u64 max_rate = 0;
        int ret = 0, i;
 
        /* Create app vsi with the TCs. Main VSI with TC0 is already set up */
@@ -6110,8 +6117,9 @@ static int i40e_configure_queue_channels(struct i40e_vsi *vsi)
                        /* Bandwidth limit through tc interface is in bytes/s,
                         * change to Mbit/s
                         */
-                       ch->max_tx_rate =
-                               vsi->mqprio_qopt.max_rate[i] / (1000000 / 8);
+                       max_rate = vsi->mqprio_qopt.max_rate[i];
+                       do_div(max_rate, I40E_BW_MBPS_DIVISOR);
+                       ch->max_tx_rate = max_rate;
 
                        list_add_tail(&ch->list, &vsi->ch_list);
 
@@ -6540,6 +6548,7 @@ static int i40e_validate_mqprio_qopt(struct i40e_vsi *vsi,
                                     struct tc_mqprio_qopt_offload *mqprio_qopt)
 {
        u64 sum_max_rate = 0;
+       u64 max_rate = 0;
        int i;
 
        if (mqprio_qopt->qopt.offset[0] != 0 ||
@@ -6554,7 +6563,9 @@ static int i40e_validate_mqprio_qopt(struct i40e_vsi *vsi,
                                "Invalid min tx rate (greater than 0) specified\n");
                        return -EINVAL;
                }
-               sum_max_rate += (mqprio_qopt->max_rate[i] / (1000000 / 8));
+               max_rate = mqprio_qopt->max_rate[i];
+               do_div(max_rate, I40E_BW_MBPS_DIVISOR);
+               sum_max_rate += max_rate;
 
                if (i >= mqprio_qopt->qopt.num_tc - 1)
                        break;
@@ -6698,14 +6709,18 @@ config_tc:
 
        if (pf->flags & I40E_FLAG_TC_MQPRIO) {
                if (vsi->mqprio_qopt.max_rate[0]) {
-                       u64 max_tx_rate = vsi->mqprio_qopt.max_rate[0] /
-                                                               (1000000 / 8);
+                       u64 max_tx_rate = vsi->mqprio_qopt.max_rate[0];
+
+                       do_div(max_tx_rate, I40E_BW_MBPS_DIVISOR);
                        ret = i40e_set_bw_limit(vsi, vsi->seid, max_tx_rate);
                        if (!ret) {
+                               u64 credits = max_tx_rate;
+
+                               do_div(credits, I40E_BW_CREDIT_DIVISOR);
                                dev_dbg(&vsi->back->pdev->dev,
                                        "Set tx rate of %llu Mbps (count of 50Mbps %llu) for vsi->seid %u\n",
                                        max_tx_rate,
-                                       max_tx_rate / I40E_BW_CREDIT_DIVISOR,
+                                       credits,
                                        vsi->seid);
                        } else {
                                need_reset = true;
@@ -8166,14 +8181,17 @@ static int i40e_rebuild_channels(struct i40e_vsi *vsi)
                        return ret;
                }
                if (ch->max_tx_rate) {
+                       u64 credits = ch->max_tx_rate;
+
                        if (i40e_set_bw_limit(vsi, ch->seid,
                                              ch->max_tx_rate))
                                return -EINVAL;
 
+                       do_div(credits, I40E_BW_CREDIT_DIVISOR);
                        dev_dbg(&vsi->back->pdev->dev,
                                "Set tx rate of %llu Mbps (count of 50Mbps %llu) for vsi->seid %u\n",
                                ch->max_tx_rate,
-                               ch->max_tx_rate / I40E_BW_CREDIT_DIVISOR,
+                               credits,
                                ch->seid);
                }
        }
@@ -8446,17 +8464,21 @@ static void i40e_rebuild(struct i40e_pf *pf, bool reinit, bool lock_acquired)
        }
 
        if (vsi->mqprio_qopt.max_rate[0]) {
-               u64 max_tx_rate = vsi->mqprio_qopt.max_rate[0] / (1000000 / 8);
+               u64 max_tx_rate = vsi->mqprio_qopt.max_rate[0];
+               u64 credits = 0;
 
+               do_div(max_tx_rate, I40E_BW_MBPS_DIVISOR);
                ret = i40e_set_bw_limit(vsi, vsi->seid, max_tx_rate);
-               if (!ret)
-                       dev_dbg(&vsi->back->pdev->dev,
-                               "Set tx rate of %llu Mbps (count of 50Mbps %llu) for vsi->seid %u\n",
-                               max_tx_rate,
-                               max_tx_rate / I40E_BW_CREDIT_DIVISOR,
-                               vsi->seid);
-               else
+               if (ret)
                        goto end_unlock;
+
+               credits = max_tx_rate;
+               do_div(credits, I40E_BW_CREDIT_DIVISOR);
+               dev_dbg(&vsi->back->pdev->dev,
+                       "Set tx rate of %llu Mbps (count of 50Mbps %llu) for vsi->seid %u\n",
+                       max_tx_rate,
+                       credits,
+                       vsi->seid);
        }
 
        /* PF Main VSI is rebuild by now, go ahead and rebuild channel VSIs