Re: [PATCH 6/8] RDMA/bng_re: Enable Firmware channel and query device attributes

On Fri, Sep 12, 2025 at 2:12 PM Simon Horman [off-list ref] wrote:

On Fri, Aug 29, 2025 at 12:30:40PM +0000, Siva Reddy Kallam wrote:

quoted

Enable Firmware channel and query device attributes

Signed-off-by: Siva Reddy Kallam <siva.kallam@broadcom.com>
Reviewed-by: Usman Ansari <redacted>

...

quoted

diff --git a/drivers/infiniband/hw/bng_re/bng_sp.c b/drivers/infiniband/hw/bng_re/bng_sp.c

...

quoted

+int bng_re_get_dev_attr(struct bng_re_rcfw *rcfw)
+{
+     struct bng_re_dev_attr *attr = rcfw->res->dattr;
+     struct creq_query_func_resp resp = {};
+     struct bng_re_cmdqmsg msg = {};
+     struct creq_query_func_resp_sb *sb;
+     struct bng_re_rcfw_sbuf sbuf;
+     struct bng_re_chip_ctx *cctx;
+     struct cmdq_query_func req = {};
+     u8 *tqm_alloc;
+     int i, rc;
+     u32 temp;
+
+     cctx = rcfw->res->cctx;

Similar to my comment on an earlier patch in this series,
cctx appears to be initialised but otherwise unused in this function.

Thank you for the review. We will fix it in the next version of the patchset.

quoted

+     bng_re_rcfw_cmd_prep((struct cmdq_base *)&req,
+                          CMDQ_BASE_OPCODE_QUERY_FUNC,
+                          sizeof(req));
+
+     sbuf.size = ALIGN(sizeof(*sb), BNG_FW_CMDQE_UNITS);
+     sbuf.sb = dma_alloc_coherent(&rcfw->pdev->dev, sbuf.size,
+                                  &sbuf.dma_addr, GFP_KERNEL);
+     if (!sbuf.sb)
+             return -ENOMEM;
+     sb = sbuf.sb;
+     req.resp_size = sbuf.size / BNG_FW_CMDQE_UNITS;
+     bng_re_fill_cmdqmsg(&msg, &req, &resp, &sbuf, sizeof(req),
+                         sizeof(resp), 0);
+     rc = bng_re_rcfw_send_message(rcfw, &msg);
+     if (rc)
+             goto bail;
+     /* Extract the context from the side buffer */
+     attr->max_qp = le32_to_cpu(sb->max_qp);
+     /* max_qp value reported by FW doesn't include the QP1 */
+     attr->max_qp += 1;
+     attr->max_qp_rd_atom =
+             sb->max_qp_rd_atom > BNG_RE_MAX_OUT_RD_ATOM ?
+             BNG_RE_MAX_OUT_RD_ATOM : sb->max_qp_rd_atom;
+     attr->max_qp_init_rd_atom =
+             sb->max_qp_init_rd_atom > BNG_RE_MAX_OUT_RD_ATOM ?
+             BNG_RE_MAX_OUT_RD_ATOM : sb->max_qp_init_rd_atom;
+     attr->max_qp_wqes = le16_to_cpu(sb->max_qp_wr) - 1;
+
+     /* Adjust for max_qp_wqes for variable wqe */
+     attr->max_qp_wqes = min_t(u32, attr->max_qp_wqes, BNG_VAR_MAX_WQE - 1);
+
+     attr->max_qp_sges = min_t(u32, sb->max_sge_var_wqe, BNG_VAR_MAX_SGE);
+     attr->max_cq = le32_to_cpu(sb->max_cq);
+     attr->max_cq_wqes = le32_to_cpu(sb->max_cqe);
+     attr->max_cq_sges = attr->max_qp_sges;
+     attr->max_mr = le32_to_cpu(sb->max_mr);
+     attr->max_mw = le32_to_cpu(sb->max_mw);
+
+     attr->max_mr_size = le64_to_cpu(sb->max_mr_size);
+     attr->max_pd = 64 * 1024;
+     attr->max_raw_ethy_qp = le32_to_cpu(sb->max_raw_eth_qp);
+     attr->max_ah = le32_to_cpu(sb->max_ah);
+
+     attr->max_srq = le16_to_cpu(sb->max_srq);
+     attr->max_srq_wqes = le32_to_cpu(sb->max_srq_wr) - 1;
+     attr->max_srq_sges = sb->max_srq_sge;
+     attr->max_pkey = 1;
+     attr->max_inline_data = le32_to_cpu(sb->max_inline_data);
+     /*
+      * Read the max gid supported by HW.
+      * For each entry in HW  GID in HW table, we consume 2
+      * GID entries in the kernel GID table.  So max_gid reported
+      * to stack can be up to twice the value reported by the HW, up to 256 gids.
+      */
+     attr->max_sgid = le32_to_cpu(sb->max_gid);
+     attr->max_sgid = min_t(u32, BNG_RE_NUM_GIDS_SUPPORTED, 2 * attr->max_sgid);
+     attr->dev_cap_flags = le16_to_cpu(sb->dev_cap_flags);
+     attr->dev_cap_flags2 = le16_to_cpu(sb->dev_cap_ext_flags_2);
+
+     if (_is_max_srq_ext_supported(attr->dev_cap_flags2))
+             attr->max_srq += le16_to_cpu(sb->max_srq_ext);
+
+     bng_re_query_version(rcfw, attr->fw_ver);
+     for (i = 0; i < BNG_MAX_TQM_ALLOC_REQ / 4; i++) {
+             temp = le32_to_cpu(sb->tqm_alloc_reqs[i]);
+             tqm_alloc = (u8 *)&temp;
+             attr->tqm_alloc_reqs[i * 4] = *tqm_alloc;
+             attr->tqm_alloc_reqs[i * 4 + 1] = *(++tqm_alloc);
+             attr->tqm_alloc_reqs[i * 4 + 2] = *(++tqm_alloc);
+             attr->tqm_alloc_reqs[i * 4 + 3] = *(++tqm_alloc);
+     }
+
+     attr->max_dpi = le32_to_cpu(sb->max_dpi);
+     attr->is_atomic = bng_re_is_atomic_cap(rcfw);
+bail:
+     dma_free_coherent(&rcfw->pdev->dev, sbuf.size,
+                       sbuf.sb, sbuf.dma_addr);
+     return rc;
+}

...