platform/mellanox: mlxbf-pmc: Fix reading of unprogrammed events

[ Upstream commit 0f5969452e162efc50bdc98968fb62b424a9874b ]

This fix involves 2 changes:
 - All event regs have a reset value of 0, which is not a valid
   event_number as per the event_list for most blocks and hence seen
   as an error. Add a "disable" event with event_number 0 for all blocks.

 - The enable bit for each counter need not be checked before
   reading the event info, and hence removed.

Fixes: 1a218d312e65 ("platform/mellanox: mlxbf-pmc: Add Mellanox BlueField PMC driver")
Signed-off-by: Shravan Kumar Ramani <shravankr@nvidia.com>
Reviewed-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: David Thompson <davthompson@nvidia.com>
Link: https://lore.kernel.org/r/04d0213932d32681de1c716b54320ed894e52425.1693917738.git.shravankr@nvidia.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/platform/mellanox/mlxbf-pmc.c b/drivers/platform/mellanox/mlxbf-pmc.c
index 95afcae..2d4bbe9 100644 (file)
--- a/drivers/platform/mellanox/mlxbf-pmc.c
+++ b/drivers/platform/mellanox/mlxbf-pmc.c
@@ -191,6 +191,7 @@ static const struct mlxbf_pmc_events mlxbf_pmc_smgen_events[] = {
 };
 
 static const struct mlxbf_pmc_events mlxbf_pmc_trio_events_1[] = {
+       { 0x0, "DISABLE" },
        { 0xa0, "TPIO_DATA_BEAT" },
        { 0xa1, "TDMA_DATA_BEAT" },
        { 0xa2, "MAP_DATA_BEAT" },
@@ -214,6 +215,7 @@ static const struct mlxbf_pmc_events mlxbf_pmc_trio_events_1[] = {
 };
 
 static const struct mlxbf_pmc_events mlxbf_pmc_trio_events_2[] = {
+       { 0x0, "DISABLE" },
        { 0xa0, "TPIO_DATA_BEAT" },
        { 0xa1, "TDMA_DATA_BEAT" },
        { 0xa2, "MAP_DATA_BEAT" },
@@ -246,6 +248,7 @@ static const struct mlxbf_pmc_events mlxbf_pmc_trio_events_2[] = {
 };
 
 static const struct mlxbf_pmc_events mlxbf_pmc_ecc_events[] = {
+       { 0x0, "DISABLE" },
        { 0x100, "ECC_SINGLE_ERROR_CNT" },
        { 0x104, "ECC_DOUBLE_ERROR_CNT" },
        { 0x114, "SERR_INJ" },
@@ -258,6 +261,7 @@ static const struct mlxbf_pmc_events mlxbf_pmc_ecc_events[] = {
 };
 
 static const struct mlxbf_pmc_events mlxbf_pmc_mss_events[] = {
+       { 0x0, "DISABLE" },
        { 0xc0, "RXREQ_MSS" },
        { 0xc1, "RXDAT_MSS" },
        { 0xc2, "TXRSP_MSS" },
@@ -265,6 +269,7 @@ static const struct mlxbf_pmc_events mlxbf_pmc_mss_events[] = {
 };
 
 static const struct mlxbf_pmc_events mlxbf_pmc_hnf_events[] = {
+       { 0x0, "DISABLE" },
        { 0x45, "HNF_REQUESTS" },
        { 0x46, "HNF_REJECTS" },
        { 0x47, "ALL_BUSY" },
@@ -323,6 +328,7 @@ static const struct mlxbf_pmc_events mlxbf_pmc_hnf_events[] = {
 };
 
 static const struct mlxbf_pmc_events mlxbf_pmc_hnfnet_events[] = {
+       { 0x0, "DISABLE" },
        { 0x12, "CDN_REQ" },
        { 0x13, "DDN_REQ" },
        { 0x14, "NDN_REQ" },
@@ -892,7 +898,7 @@ static int mlxbf_pmc_read_event(int blk_num, uint32_t cnt_num, bool is_l3,
                                uint64_t *result)
 {
        uint32_t perfcfg_offset, perfval_offset;
-       uint64_t perfmon_cfg, perfevt, perfctl;
+       uint64_t perfmon_cfg, perfevt;
 
        if (cnt_num >= pmc->block[blk_num].counters)
                return -EINVAL;
@@ -906,25 +912,6 @@ static int mlxbf_pmc_read_event(int blk_num, uint32_t cnt_num, bool is_l3,
 
        /* Set counter in "read" mode */
        perfmon_cfg = FIELD_PREP(MLXBF_PMC_PERFMON_CONFIG_ADDR,
-                                MLXBF_PMC_PERFCTL);
-       perfmon_cfg |= FIELD_PREP(MLXBF_PMC_PERFMON_CONFIG_STROBE, 1);
-       perfmon_cfg |= FIELD_PREP(MLXBF_PMC_PERFMON_CONFIG_WR_R_B, 0);
-
-       if (mlxbf_pmc_write(pmc->block[blk_num].mmio_base + perfcfg_offset,
-                           MLXBF_PMC_WRITE_REG_64, perfmon_cfg))
-               return -EFAULT;
-
-       /* Check if the counter is enabled */
-
-       if (mlxbf_pmc_read(pmc->block[blk_num].mmio_base + perfval_offset,
-                          MLXBF_PMC_READ_REG_64, &perfctl))
-               return -EFAULT;
-
-       if (!FIELD_GET(MLXBF_PMC_PERFCTL_EN0, perfctl))
-               return -EINVAL;
-
-       /* Set counter in "read" mode */
-       perfmon_cfg = FIELD_PREP(MLXBF_PMC_PERFMON_CONFIG_ADDR,
                                 MLXBF_PMC_PERFEVT);
        perfmon_cfg |= FIELD_PREP(MLXBF_PMC_PERFMON_CONFIG_STROBE, 1);
        perfmon_cfg |= FIELD_PREP(MLXBF_PMC_PERFMON_CONFIG_WR_R_B, 0);