common/sfc_efx/base: improve MCDI version/boot clarity

Improve the clarity of the code.

Fixes: 833cfcd590e2 ("common/sfc_efx/base: add API for querying board info")
Fixes: 312191e86eb0 ("common/sfc_efx/base: refactor version / boot info get helper")

Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>

diff --git a/drivers/common/sfc_efx/base/efx_mcdi.c b/drivers/common/sfc_efx/base/efx_mcdi.c
index 8c984d8..ca44267 100644 (file)
--- a/drivers/common/sfc_efx/base/efx_mcdi.c
+++ b/drivers/common/sfc_efx/base/efx_mcdi.c
@@ -964,15 +964,17 @@ efx_mcdi_ev_death(
        __checkReturn           efx_rc_t
 efx_mcdi_get_version(
        __in                    efx_nic_t *enp,
-       __in                    uint32_t flags_req,
+       __in                    uint32_t flags,
        __out                   efx_mcdi_version_t *verp)
 {
        efx_nic_board_info_t *board_infop = &verp->emv_board_info;
        EFX_MCDI_DECLARE_BUF(payload,
            MC_CMD_GET_VERSION_EXT_IN_LEN,
            MC_CMD_GET_VERSION_V2_OUT_LEN);
-       size_t min_resp_len_required;
+       efx_word_t *ver_words;
+       uint16_t version[4];
        efx_mcdi_req_t req;
+       uint32_t firmware;
        efx_rc_t rc;
 
        EFX_STATIC_ASSERT(sizeof (verp->emv_version) ==
@@ -996,18 +998,14 @@ efx_mcdi_get_version(
        req.emr_in_buf = payload;
        req.emr_out_buf = payload;
 
-       if (flags_req != 0) {
+       if ((flags & EFX_MCDI_VERSION_BOARD_INFO) != 0) {
                /* Request basic + extended version information. */
                req.emr_in_length = MC_CMD_GET_VERSION_EXT_IN_LEN;
                req.emr_out_length = MC_CMD_GET_VERSION_V2_OUT_LEN;
-
-               min_resp_len_required = MC_CMD_GET_VERSION_V2_OUT_LEN;
        } else {
                /* Request only basic version information. */
                req.emr_in_length = MC_CMD_GET_VERSION_IN_LEN;
                req.emr_out_length = MC_CMD_GET_VERSION_OUT_LEN;
-
-               min_resp_len_required = MC_CMD_GET_VERSION_V0_OUT_LEN;
        }
 
        efx_mcdi_execute(enp, &req);
@@ -1017,33 +1015,36 @@ efx_mcdi_get_version(
                goto fail1;
        }
 
-       if (req.emr_out_length_used < min_resp_len_required) {
+       /* bootrom support */
+       if (req.emr_out_length_used == MC_CMD_GET_VERSION_V0_OUT_LEN) {
+               version[0] = version[1] = version[2] = version[3] = 0;
+               firmware = MCDI_OUT_DWORD(req, GET_VERSION_OUT_FIRMWARE);
+               goto out;
+       }
+
+       if (req.emr_out_length_used < req.emr_out_length) {
                rc = EMSGSIZE;
                goto fail2;
        }
 
-       memset(verp, 0, sizeof (*verp));
-
-       if (req.emr_out_length_used > min_resp_len_required) {
-               efx_word_t *ver_words;
-
-               if (req.emr_out_length_used < MC_CMD_GET_VERSION_OUT_LEN) {
-                       rc = EMSGSIZE;
-                       goto fail3;
-               }
-
-               ver_words = MCDI_OUT2(req, efx_word_t, GET_VERSION_OUT_VERSION);
+       ver_words = MCDI_OUT2(req, efx_word_t, GET_VERSION_OUT_VERSION);
+       version[0] = EFX_WORD_FIELD(ver_words[0], EFX_WORD_0);
+       version[1] = EFX_WORD_FIELD(ver_words[1], EFX_WORD_0);
+       version[2] = EFX_WORD_FIELD(ver_words[2], EFX_WORD_0);
+       version[3] = EFX_WORD_FIELD(ver_words[3], EFX_WORD_0);
+       firmware = MCDI_OUT_DWORD(req, GET_VERSION_OUT_FIRMWARE);
 
-               verp->emv_version[0] = EFX_WORD_FIELD(ver_words[0], EFX_WORD_0);
-               verp->emv_version[1] = EFX_WORD_FIELD(ver_words[1], EFX_WORD_0);
-               verp->emv_version[2] = EFX_WORD_FIELD(ver_words[2], EFX_WORD_0);
-               verp->emv_version[3] = EFX_WORD_FIELD(ver_words[3], EFX_WORD_0);
-       }
+out:
+       memset(verp, 0, sizeof (*verp));
 
-       verp->emv_firmware = MCDI_OUT_DWORD(req, GET_VERSION_OUT_FIRMWARE);
+       verp->emv_version[0] = version[0];
+       verp->emv_version[1] = version[1];
+       verp->emv_version[2] = version[2];
+       verp->emv_version[3] = version[3];
+       verp->emv_firmware = firmware;
 
        verp->emv_flags = MCDI_OUT_DWORD(req, GET_VERSION_V2_OUT_FLAGS);
-       verp->emv_flags &= flags_req;
+       verp->emv_flags &= flags;
 
        if ((verp->emv_flags & EFX_MCDI_VERSION_BOARD_INFO) != 0) {
                memcpy(board_infop->enbi_serial,
@@ -1058,8 +1059,6 @@ efx_mcdi_get_version(
 
        return (0);
 
-fail3:
-       EFSYS_PROBE(fail3);
 fail2:
        EFSYS_PROBE(fail2);
 fail1:
@@ -1089,6 +1088,12 @@ efx_mcdi_get_boot_status(
 
        efx_mcdi_execute_quiet(enp, &req);
 
+       /*
+        * NOTE: Unprivileged functions cannot access boot status,
+        *       so the MCDI request will return EACCES. This is
+        *       also checked in efx_mcdi_version.
+        */
+
        if (req.emr_rc != 0) {
                rc = req.emr_rc;
                goto fail1;