bnxt_en: update RSS config using difference algorithm

Hardware is unable to realize all legal firmware interface state values
for hash_type.  For example, if 4-tuple TCP_IPV4 hash is enabled,
4-tuple UDP_IPV4 hash must also be enabled.  By providing the bits the
user intended to change instead of the possible illegal intermediate
states, the firmware is able to make better compromises when deciding
which bits to ignore.

With this new mechansim, we can now report the actual configured hash
back to the user.  Add bnxt_hwrm_update_rss_hash_cfg() to report the
actual hash after user configuration.
Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -5294,7 +5294,15 @@ __bnxt_hwrm_vnic_set_rss(struct bnxt *bp, struct hwrm_vnic_rss_cfg_input *req,
 	else
 		bnxt_fill_hw_rss_tbl(bp, vnic);
 
+	if (bp->rss_hash_delta) {
+		req->hash_type = cpu_to_le32(bp->rss_hash_delta);
+		if (bp->rss_hash_cfg & bp->rss_hash_delta)
+			req->flags |= VNIC_RSS_CFG_REQ_FLAGS_HASH_TYPE_INCLUDE;
+		else
+			req->flags |= VNIC_RSS_CFG_REQ_FLAGS_HASH_TYPE_EXCLUDE;
+	} else {
 		req->hash_type = cpu_to_le32(bp->rss_hash_cfg);
+	}
 	req->hash_mode_flags = VNIC_RSS_CFG_REQ_HASH_MODE_FLAGS_DEFAULT;
 	req->ring_grp_tbl_addr = cpu_to_le64(vnic->rss_table_dma_addr);
 	req->hash_key_tbl_addr = cpu_to_le64(vnic->rss_hash_key_dma_addr);
@@ -5355,6 +5363,25 @@ static int bnxt_hwrm_vnic_set_rss_p5(struct bnxt *bp, u16 vnic_id, bool set_rss)
 	return rc;
 }
 
+static void bnxt_hwrm_update_rss_hash_cfg(struct bnxt *bp)
+{
+	struct bnxt_vnic_info *vnic = &bp->vnic_info[0];
+	struct hwrm_vnic_rss_qcfg_output *resp;
+	struct hwrm_vnic_rss_qcfg_input *req;
+
+	if (hwrm_req_init(bp, req, HWRM_VNIC_RSS_QCFG))
+		return;
+
+	/* all contexts configured to same hash_type, zero always exists */
+	req->rss_ctx_idx = cpu_to_le16(vnic->fw_rss_cos_lb_ctx[0]);
+	resp = hwrm_req_hold(bp, req);
+	if (!hwrm_req_send(bp, req)) {
+		bp->rss_hash_cfg = le32_to_cpu(resp->hash_type) ?: bp->rss_hash_cfg;
+		bp->rss_hash_delta = 0;
+	}
+	hwrm_req_drop(bp, req);
+}
+
 static int bnxt_hwrm_vnic_set_hds(struct bnxt *bp, u16 vnic_id)
 {
 	struct bnxt_vnic_info *vnic = &bp->vnic_info[vnic_id];
@@ -5612,6 +5639,8 @@ static int bnxt_hwrm_vnic_qcaps(struct bnxt *bp)
 		    (BNXT_CHIP_P5_THOR(bp) &&
 		     !(bp->fw_cap & BNXT_FW_CAP_EXT_HW_STATS_SUPPORTED)))
 			bp->fw_cap |= BNXT_FW_CAP_VLAN_RX_STRIP;
+		if (flags & VNIC_QCAPS_RESP_FLAGS_RSS_HASH_TYPE_DELTA_CAP)
+			bp->fw_cap |= BNXT_FW_CAP_RSS_HASH_TYPE_DELTA;
 		bp->max_tpa_v2 = le16_to_cpu(resp->max_aggs_supported);
 		if (bp->max_tpa_v2) {
 			if (BNXT_CHIP_P5_THOR(bp))
@@ -8806,6 +8835,8 @@ static int bnxt_init_chip(struct bnxt *bp, bool irq_re_init)
 	rc = bnxt_setup_vnic(bp, 0);
 	if (rc)
 		goto err_out;
+	if (bp->fw_cap & BNXT_FW_CAP_RSS_HASH_TYPE_DELTA)
+		bnxt_hwrm_update_rss_hash_cfg(bp);
 
 	if (bp->flags & BNXT_FLAG_RFS) {
 		rc = bnxt_alloc_rfs_vnics(bp);
@@ -12241,6 +12272,8 @@ static void bnxt_set_dflt_rss_hash_type(struct bnxt *bp)
 			   VNIC_RSS_CFG_REQ_HASH_TYPE_TCP_IPV4 |
 			   VNIC_RSS_CFG_REQ_HASH_TYPE_IPV6 |
 			   VNIC_RSS_CFG_REQ_HASH_TYPE_TCP_IPV6;
+	if (bp->fw_cap & BNXT_FW_CAP_RSS_HASH_TYPE_DELTA)
+		bp->rss_hash_delta = bp->rss_hash_cfg;
 	if (BNXT_CHIP_P4_PLUS(bp) && bp->hwrm_spec_code >= 0x10501) {
 		bp->flags |= BNXT_FLAG_UDP_RSS_CAP;
 		bp->rss_hash_cfg |= VNIC_RSS_CFG_REQ_HASH_TYPE_UDP_IPV4 |

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1900,6 +1900,7 @@ struct bnxt {
 	u16			*rss_indir_tbl;
 	u16			rss_indir_tbl_entries;
 	u32			rss_hash_cfg;
+	u32			rss_hash_delta;
 
 	u16			max_mtu;
 	u8			max_tc;
@@ -1965,6 +1966,7 @@ struct bnxt {
 	#define BNXT_FW_CAP_CFA_RFS_RING_TBL_IDX_V2	0x00010000
 	#define BNXT_FW_CAP_PCIE_STATS_SUPPORTED	0x00020000
 	#define BNXT_FW_CAP_EXT_STATS_SUPPORTED		0x00040000
+	#define BNXT_FW_CAP_RSS_HASH_TYPE_DELTA		0x00080000
 	#define BNXT_FW_CAP_ERR_RECOVER_RELOAD		0x00100000
 	#define BNXT_FW_CAP_HOT_RESET			0x00200000
 	#define BNXT_FW_CAP_PTP_RTC			0x00400000

drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c

@@ -1234,6 +1234,8 @@ static int bnxt_srxfh(struct bnxt *bp, struct ethtool_rxnfc *cmd)
 	if (bp->rss_hash_cfg == rss_hash_cfg)
 		return 0;
 
+	if (bp->fw_cap & BNXT_FW_CAP_RSS_HASH_TYPE_DELTA)
+		bp->rss_hash_delta = bp->rss_hash_cfg ^ rss_hash_cfg;
 	bp->rss_hash_cfg = rss_hash_cfg;
 	if (netif_running(bp->dev)) {
 		bnxt_close_nic(bp, false, false);

drivers/net/ethernet/broadcom/bnxt/bnxt_hsi.h

@@ -6768,6 +6768,53 @@ struct hwrm_vnic_rss_cfg_cmd_err {
 	u8	unused_0[7];
 };
 
+/* hwrm_vnic_rss_qcfg_input (size:192b/24B) */
+struct hwrm_vnic_rss_qcfg_input {
+	__le16	req_type;
+	__le16	cmpl_ring;
+	__le16	seq_id;
+	__le16	target_id;
+	__le64	resp_addr;
+	__le16	rss_ctx_idx;
+	__le16	vnic_id;
+	u8	unused_0[4];
+};
+
+/* hwrm_vnic_rss_qcfg_output (size:512b/64B) */
+struct hwrm_vnic_rss_qcfg_output {
+	__le16	error_code;
+	__le16	req_type;
+	__le16	seq_id;
+	__le16	resp_len;
+	__le32	hash_type;
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_IPV4                0x1UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_TCP_IPV4            0x2UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_UDP_IPV4            0x4UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_IPV6                0x8UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_TCP_IPV6            0x10UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_UDP_IPV6            0x20UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_IPV6_FLOW_LABEL     0x40UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_AH_SPI_IPV4         0x80UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_ESP_SPI_IPV4        0x100UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_AH_SPI_IPV6         0x200UL
+	#define VNIC_RSS_QCFG_RESP_HASH_TYPE_ESP_SPI_IPV6        0x400UL
+	u8	unused_0[4];
+	__le32	hash_key[10];
+	u8	hash_mode_flags;
+	#define VNIC_RSS_QCFG_RESP_HASH_MODE_FLAGS_DEFAULT         0x1UL
+	#define VNIC_RSS_QCFG_RESP_HASH_MODE_FLAGS_INNERMOST_4     0x2UL
+	#define VNIC_RSS_QCFG_RESP_HASH_MODE_FLAGS_INNERMOST_2     0x4UL
+	#define VNIC_RSS_QCFG_RESP_HASH_MODE_FLAGS_OUTERMOST_4     0x8UL
+	#define VNIC_RSS_QCFG_RESP_HASH_MODE_FLAGS_OUTERMOST_2     0x10UL
+	u8	ring_select_mode;
+	#define VNIC_RSS_QCFG_RESP_RING_SELECT_MODE_TOEPLITZ          0x0UL
+	#define VNIC_RSS_QCFG_RESP_RING_SELECT_MODE_XOR               0x1UL
+	#define VNIC_RSS_QCFG_RESP_RING_SELECT_MODE_TOEPLITZ_CHECKSUM 0x2UL
+	#define VNIC_RSS_QCFG_RESP_RING_SELECT_MODE_LAST             VNIC_RSS_QCFG_RESP_RING_SELECT_MODE_TOEPLITZ_CHECKSUM
+	u8	unused_1[5];
+	u8	valid;
+};
+
 /* hwrm_vnic_plcmodes_cfg_input (size:320b/40B) */
 struct hwrm_vnic_plcmodes_cfg_input {
 	__le16	req_type;