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

[Simon Horman <horms@kernel.org>]

On Fri, Aug 29, 2025 at 12:30:40PM +0000, Siva Reddy Kallam wrote:
> Enable Firmware channel and query device attributes
> 
> Signed-off-by: Siva Reddy Kallam <siva.kallam@broadcom.com>
> Reviewed-by: Usman Ansari <usman.ansari@broadcom.com>

...

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

...

> +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.


> +	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;
> +}

...