nfp: abm: add functions to update DSCP -> virtual queue map

Learn how to set the DSCP map.  FW uses a packed array which
geometry depends on the number of supported priorities and
virtual queues.  Write code to assemble this map and to communicate
the setting to the FW via mailbox.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/abm/ctrl.c

 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
 /* Copyright (C) 2018 Netronome Systems, Inc. */
 
+#include <linux/bitops.h>
 #include <linux/kernel.h>
 #include <linux/log2.h>
 
@@ -221,6 +222,28 @@ int nfp_abm_ctrl_qm_disable(struct nfp_abm *abm)
 			    NULL, 0, NULL, 0);
 }
 
+int nfp_abm_ctrl_prio_map_update(struct nfp_abm_link *alink, u32 *packed)
+{
+	struct nfp_net *nn = alink->vnic;
+	unsigned int i;
+	int err;
+
+	/* Write data_len and wipe reserved */
+	nn_writeq(nn, nn->tlv_caps.mbox_off + NFP_NET_ABM_MBOX_DATALEN,
+		  alink->abm->prio_map_len);
+
+	for (i = 0; i < alink->abm->prio_map_len; i += sizeof(u32))
+		nn_writel(nn, nn->tlv_caps.mbox_off + NFP_NET_ABM_MBOX_DATA + i,
+			  packed[i / sizeof(u32)]);
+
+	err = nfp_net_reconfig_mbox(nn,
+				    NFP_NET_CFG_MBOX_CMD_PCI_DSCP_PRIOMAP_SET);
+	if (err)
+		nfp_err(alink->abm->app->cpp,
+			"setting DSCP -> VQ map failed with error %d\n", err);
+	return err;
+}
+
 static int nfp_abm_ctrl_prio_check_params(struct nfp_abm_link *alink)
 {
 	struct nfp_abm *abm = alink->abm;

drivers/net/ethernet/netronome/nfp/abm/main.h

@@ -220,4 +220,5 @@ u64 nfp_abm_ctrl_stat_non_sto(struct nfp_abm_link *alink, unsigned int i);
 u64 nfp_abm_ctrl_stat_sto(struct nfp_abm_link *alink, unsigned int i);
 int nfp_abm_ctrl_qm_enable(struct nfp_abm *abm);
 int nfp_abm_ctrl_qm_disable(struct nfp_abm *abm);
+int nfp_abm_ctrl_prio_map_update(struct nfp_abm_link *alink, u32 *packed);
 #endif

drivers/net/ethernet/netronome/nfp/nfp_net.h

@@ -868,6 +868,7 @@ unsigned int nfp_net_rss_key_sz(struct nfp_net *nn);
 void nfp_net_rss_write_itbl(struct nfp_net *nn);
 void nfp_net_rss_write_key(struct nfp_net *nn);
 void nfp_net_coalesce_write_cfg(struct nfp_net *nn);
+int nfp_net_reconfig_mbox(struct nfp_net *nn, u32 mbox_cmd);
 
 unsigned int
 nfp_net_irqs_alloc(struct pci_dev *pdev, struct msix_entry *irq_entries,

drivers/net/ethernet/netronome/nfp/nfp_net_common.c

@@ -279,7 +279,7 @@ int nfp_net_reconfig(struct nfp_net *nn, u32 update)
  *
  * Return: Negative errno on error, 0 on success
  */
-static int nfp_net_reconfig_mbox(struct nfp_net *nn, u32 mbox_cmd)
+int nfp_net_reconfig_mbox(struct nfp_net *nn, u32 mbox_cmd)
 {
 	u32 mbox = nn->tlv_caps.mbox_off;
 	int ret;

drivers/net/ethernet/netronome/nfp/nfp_net_ctrl.h

@@ -397,6 +397,8 @@
 #define NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_ADD 1
 #define NFP_NET_CFG_MBOX_CMD_CTAG_FILTER_KILL 2
 
+#define NFP_NET_CFG_MBOX_CMD_PCI_DSCP_PRIOMAP_SET	5
+
 /**
  * VLAN filtering using general use mailbox
  * %NFP_NET_CFG_VLAN_FILTER:		Base address of VLAN filter mailbox