net/sfc/base: use MAC stats DMA buffer size from caps

For Medford2 the DMA buffer used for one-shot or periodic MAC stats
has been extended. Ensure the MAC stats DMA buffer size is large
enough to hold the number of stats counters supported by firmware.

Signed-off-by: Andy Moreton <amoreton@solarflare.com>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>

diff --git a/drivers/net/sfc/base/efx_mcdi.c b/drivers/net/sfc/base/efx_mcdi.c
index a593b3f..a78a226 100644 (file)
--- a/drivers/net/sfc/base/efx_mcdi.c
+++ b/drivers/net/sfc/base/efx_mcdi.c
@@ -1791,7 +1791,7 @@ efx_mcdi_mac_stats(
 {
        efx_mcdi_req_t req;
        uint8_t payload[MAX(MC_CMD_MAC_STATS_IN_LEN,
-                           MC_CMD_MAC_STATS_OUT_DMA_LEN)];
+                           MC_CMD_MAC_STATS_V2_OUT_DMA_LEN)];
        int clear = (action == EFX_STATS_CLEAR);
        int upload = (action == EFX_STATS_UPLOAD);
        int enable = (action == EFX_STATS_ENABLE_NOEVENTS);
@@ -1804,7 +1804,7 @@ efx_mcdi_mac_stats(
        req.emr_in_buf = payload;
        req.emr_in_length = MC_CMD_MAC_STATS_IN_LEN;
        req.emr_out_buf = payload;
-       req.emr_out_length = MC_CMD_MAC_STATS_OUT_DMA_LEN;
+       req.emr_out_length = MC_CMD_MAC_STATS_V2_OUT_DMA_LEN;
 
        MCDI_IN_POPULATE_DWORD_6(req, MAC_STATS_IN_CMD,
            MAC_STATS_IN_DMA, upload,
@@ -1815,7 +1815,8 @@ efx_mcdi_mac_stats(
            MAC_STATS_IN_PERIOD_MS, (enable | events) ? period_ms : 0);
 
        if (enable || events || upload) {
-               uint32_t bytes = MC_CMD_MAC_NSTATS * sizeof (uint64_t);
+               const efx_nic_cfg_t *encp = &enp->en_nic_cfg;
+               uint32_t bytes;
 
                /* Periodic stats or stats upload require a DMA buffer */
                if (esmp == NULL) {
@@ -1823,10 +1824,19 @@ efx_mcdi_mac_stats(
                        goto fail1;
                }
 
-               EFX_STATIC_ASSERT(MC_CMD_MAC_NSTATS * sizeof (uint64_t) <=
-                   EFX_MAC_STATS_SIZE);
+               if (encp->enc_mac_stats_nstats < MC_CMD_MAC_NSTATS) {
+                       /* MAC stats count too small for legacy MAC stats */
+                       rc = ENOSPC;
+                       goto fail2;
+               }
+
+               bytes = encp->enc_mac_stats_nstats * sizeof (efx_qword_t);
 
-               EFSYS_ASSERT3U(bytes, <=, (uint32_t)EFSYS_MEM_SIZE(esmp));
+               if (EFSYS_MEM_SIZE(esmp) < bytes) {
+                       /* DMA buffer too small */
+                       rc = ENOSPC;
+                       goto fail3;
+               }
 
                MCDI_IN_SET_DWORD(req, MAC_STATS_IN_DMA_ADDR_LO,
                            EFSYS_MEM_ADDR(esmp) & 0xffffffff);
@@ -1850,12 +1860,16 @@ efx_mcdi_mac_stats(
                if ((req.emr_rc != ENOENT) ||
                    (enp->en_rx_qcount + enp->en_tx_qcount != 0)) {
                        rc = req.emr_rc;
-                       goto fail2;
+                       goto fail4;
                }
        }
 
        return (0);
 
+fail4:
+       EFSYS_PROBE(fail4);
+fail3:
+       EFSYS_PROBE(fail3);
 fail2:
        EFSYS_PROBE(fail2);
 fail1: