brcmfmac: add firmware-signalling hanger functions

The hanger for firmware-signalling is used to retain information for
outstanding transmit packets that await tx status.

Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Piotr Haber <phaber@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 197 insertions, 0 deletions

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c
index b123a80b17cf..a6443c667e33 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/fwsignal.c
@@ -267,9 +267,64 @@ struct brcmf_fws_mac_descriptor {
         struct pktq psq;
 };
 
+#define BRCMF_FWS_HANGER_MAXITEMS       1024
+
+/**
+ * enum brcmf_fws_hanger_item_state - state of hanger item.
+ *
+ * @WLFC_HANGER_ITEM_STATE_FREE: item is free for use.
+ * @WLFC_HANGER_ITEM_STATE_INUSE: item is in use.
+ * @WLFC_HANGER_ITEM_STATE_INUSE_SUPPRESSED: item was suppressed.
+ */
+enum brcmf_fws_hanger_item_state {
+        WLFC_HANGER_ITEM_STATE_FREE = 1,
+        WLFC_HANGER_ITEM_STATE_INUSE,
+        WLFC_HANGER_ITEM_STATE_INUSE_SUPPRESSED
+};
+
+
+/**
+ * struct brcmf_fws_hanger_item - single entry for tx pending packet.
+ *
+ * @state: entry is either free or occupied.
+ * @gen: generation.
+ * @identifier: packet identifier.
+ * @pkt: packet itself.
+ */
+struct brcmf_fws_hanger_item {
+        enum brcmf_fws_hanger_item_state state;
+        u8 gen;
+        u8 pad[2];
+        u32 identifier;
+        struct sk_buff *pkt;
+};
+
+/**
+ * struct brcmf_fws_hanger - holds packets awaiting firmware txstatus.
+ *
+ * @max_items: number of packets it can hold.
+ * @pushed: packets pushed to await txstatus.
+ * @popped: packets popped upon handling txstatus.
+ * @failed_to_push: packets that could not be pushed.
+ * @failed_to_pop: packets that could not be popped.
+ * @failed_slotfind: packets for which failed to find an entry.
+ * @slot_pos: last returned item index for a free entry.
+ * @items: array of hanger items.
+ */
+struct brcmf_fws_hanger {
+        u32 pushed;
+        u32 popped;
+        u32 failed_to_push;
+        u32 failed_to_pop;
+        u32 failed_slotfind;
+        u32 slot_pos;
+        struct brcmf_fws_hanger_item items[BRCMF_FWS_HANGER_MAXITEMS];
+};
+
 struct brcmf_fws_info {
         struct brcmf_pub *drvr;
         struct brcmf_fws_stats stats;
+        struct brcmf_fws_hanger hanger;
         struct brcmf_fws_mac_descriptor nodes[BRCMF_FWS_MAC_DESC_TABLE_SIZE];
         struct brcmf_fws_mac_descriptor other;
         int fifo_credit[NL80211_NUM_ACS+1+1];
@@ -296,6 +351,145 @@ static int brcmf_fws_get_tlv_len(struct brcmf_fws_info *fws,
 }
 #undef BRCMF_FWS_TLV_DEF
 
+static void brcmf_fws_hanger_init(struct brcmf_fws_hanger *hanger)
+{
+        int i;
+
+        brcmf_dbg(TRACE, "enter\n");
+        memset(hanger, 0, sizeof(*hanger));
+        for (i = 0; i < ARRAY_SIZE(hanger->items); i++)
+                hanger->items[i].state = WLFC_HANGER_ITEM_STATE_FREE;
+}
+
+static __used u32 brcmf_fws_hanger_get_free_slot(struct brcmf_fws_hanger *h)
+{
+        u32 i;
+
+        brcmf_dbg(TRACE, "enter\n");
+        i = (h->slot_pos + 1) % BRCMF_FWS_HANGER_MAXITEMS;
+
+        while (i != h->slot_pos) {
+                if (h->items[i].state == WLFC_HANGER_ITEM_STATE_FREE) {
+                        h->slot_pos = i;
+                        return i;
+                }
+                i++;
+                if (i == BRCMF_FWS_HANGER_MAXITEMS)
+                        i = 0;
+        }
+        brcmf_err("all slots occupied\n");
+        h->failed_slotfind++;
+        return BRCMF_FWS_HANGER_MAXITEMS;
+}
+
+static __used int brcmf_fws_hanger_pushpkt(struct brcmf_fws_hanger *h,
+                                           struct sk_buff *pkt, u32 slot_id)
+{
+        brcmf_dbg(TRACE, "enter\n");
+        if (slot_id >= BRCMF_FWS_HANGER_MAXITEMS)
+                return -ENOENT;
+
+        if (h->items[slot_id].state != BRCMF_FWS_HANGER_ITEM_STATE_FREE) {
+                brcmf_err("slot is not free\n");
+                h->failed_to_push++;
+                return -EINVAL;
+        }
+
+        h->items[slot_id].state = BRCMF_FWS_HANGER_ITEM_STATE_INUSE;
+        h->items[slot_id].pkt = pkt;
+        h->items[slot_id].identifier = slot_id;
+        h->pushed++;
+        return 0;
+}
+
+static __used int brcmf_fws_hanger_poppkt(struct brcmf_fws_hanger *h,
+                                          u32 slot_id, struct sk_buff **pktout,
+                                          bool remove_item)
+{
+        brcmf_dbg(TRACE, "enter\n");
+        if (slot_id >= BRCMF_FWS_HANGER_MAXITEMS)
+                return -ENOENT;
+
+        if (h->items[slot_id].state == BRCMF_FWS_HANGER_ITEM_STATE_FREE) {
+                brcmf_err("entry not in use\n");
+                h->failed_to_pop++;
+                return -EINVAL;
+        }
+
+        *pktout = h->items[slot_id].pkt;
+        if (remove_item) {
+                h->items[slot_id].state = BRCMF_FWS_HANGER_ITEM_STATE_FREE;
+                h->items[slot_id].pkt = NULL;
+                h->items[slot_id].identifier = 0;
+                h->items[slot_id].gen = 0xff;
+                h->popped++;
+        }
+        return 0;
+}
+
+static __used int brcmf_fws_hanger_mark_suppressed(struct brcmf_fws_hanger *h,
+                                                   u32 slot_id, u8 gen)
+{
+        brcmf_dbg(TRACE, "enter\n");
+
+        if (slot_id >= BRCMF_FWS_HANGER_MAXITEMS)
+                return -ENOENT;
+
+        h->items[slot_id].gen = gen;
+
+        if (h->items[slot_id].state != WLFC_HANGER_ITEM_STATE_INUSE) {
+                brcmf_err("entry not in use\n");
+                return -EINVAL;
+        }
+
+        h->items[slot_id].state = WLFC_HANGER_ITEM_STATE_INUSE_SUPPRESSED;
+        return 0;
+}
+
+static __used int brcmf_fws_hanger_get_genbit(struct brcmf_fws_hanger *hanger,
+                                              struct sk_buff *pkt, u32 slot_id,
+                                              int *gen)
+{
+        brcmf_dbg(TRACE, "enter\n");
+        *gen = 0xff;
+
+        if (slot_id >= BRCMF_FWS_HANGER_MAXITEMS)
+                return -ENOENT;
+
+        if (hanger->items[slot_id].state == BRCMF_FWS_HANGER_ITEM_STATE_FREE) {
+                brcmf_err("slot not in use\n");
+                return -EINVAL;
+        }
+
+        *gen = hanger->items[slot_id].gen;
+        return 0;
+}
+
+static void brcmf_fws_hanger_cleanup(struct brcmf_fws_hanger *h,
+                                     bool (*fn)(struct sk_buff *, void *),
+                                     int ifidx)
+{
+        struct sk_buff *skb;
+        int i;
+        enum brcmf_fws_hanger_item_state s;
+
+        brcmf_dbg(TRACE, "enter: ifidx=%d\n", ifidx);
+        for (i = 0; i < ARRAY_SIZE(h->items); i++) {
+                s = h->items[i].state;
+                if (s == BRCMF_FWS_HANGER_ITEM_STATE_INUSE ||
+                    s == BRCMF_FWS_HANGER_ITEM_STATE_INUSE_SUPPRESSED) {
+                        skb = h->items[i].pkt;
+                        if (fn == NULL || fn(skb, &ifidx)) {
+                                /* suppress packets freed from psq */
+                                if (s == BRCMF_FWS_HANGER_ITEM_STATE_INUSE)
+                                        brcmu_pkt_buf_free_skb(skb);
+                                h->items[i].state =
+                                        BRCMF_FWS_HANGER_ITEM_STATE_FREE;
+                        }
+                }
+        }
+}
+
 static void brcmf_fws_init_mac_descriptor(struct brcmf_fws_mac_descriptor *desc,
                                           u8 *addr, u8 ifidx)
 {
@@ -379,6 +573,7 @@ static void brcmf_fws_cleanup(struct brcmf_fws_info *fws, int ifidx)
                 brcmf_fws_mac_desc_cleanup(&table[i], matchfn, ifidx);
 
         brcmf_fws_mac_desc_cleanup(&fws->other, matchfn, ifidx);
+        brcmf_fws_hanger_cleanup(&fws->hanger, matchfn, ifidx);
 }
 
 static int brcmf_fws_rssi_indicate(struct brcmf_fws_info *fws, s8 rssi)
@@ -511,6 +706,8 @@ int brcmf_fws_init(struct brcmf_pub *drvr)
                 goto fail;
         }
 
+        brcmf_fws_hanger_init(&drvr->fws->hanger);
+
         /* create debugfs file for statistics */
         brcmf_debugfs_create_fws_stats(drvr, &drvr->fws->stats);