wil6210: add support for enhanced DMA structures

In enhanced DMA the vrings are handled internally by the FW
and are not exposed to the driver.
Instead, the driver handles descriptor rings, which are mapped
by the FW to vrings.
The completions of the TX and RX descriptors are notified to
the driver using status rings. Each status ring descriptor
includes information of the completed descriptors and the ring id
of their descriptor ring.

This patch changes struct vring to generic wil_ring to allow
its reuse for enhanced DMA descriptor rings and adds the descriptor
and status rings specific descriptors.

The vring debugfs entries have changed as follows:
- dbg_vring_index has changed to dbg_ring_index
- vrings has changed to rings
- vring_idle_trsh has changed to ring_idle_trsh
- vring_index has changed to ring_index

Signed-off-by: Gidon Studinski <gidons@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

1 files changed, 93 insertions, 17 deletions

diff --git a/drivers/net/wireless/ath/wil6210/wil6210.h b/drivers/net/wireless/ath/wil6210/wil6210.h
index 4cd8e4030fe9..810ed5b8e558 100644
--- a/drivers/net/wireless/ath/wil6210/wil6210.h
+++ b/drivers/net/wireless/ath/wil6210/wil6210.h
@@ -80,6 +80,8 @@ static inline u32 WIL_GET_BITS(u32 x, int b0, int b1)
 #define WIL6210_NAPI_BUDGET	(16) /* arbitrary */
 #define WIL_MAX_AMPDU_SIZE	(64 * 1024) /* FW/HW limit */
 #define WIL_MAX_AGG_WSIZE	(32) /* FW/HW limit */
+#define WIL6210_MAX_STATUS_RINGS	(8)
+
 /* Hardware offload block adds the following:
  * 26 bytes - 3-address QoS data header
  *  8 bytes - IV + EIV (for GCMP)
@@ -359,6 +361,12 @@ enum {
 #define TALYN_MB_FW_MAPPING_TABLE_SIZE 19
 #define MAX_FW_MAPPING_TABLE_SIZE 19
 
+/* Common representation of physical address in wil ring */
+struct wil_ring_dma_addr {
+	__le32 addr_low;
+	__le16 addr_high;
+} __packed;
+
 struct fw_map {
 	u32 from; /* linker address - from, inclusive */
 	u32 to;   /* linker address - to, exclusive */
@@ -447,7 +455,7 @@ enum { /* for wil_ctx.mapped_as */
 };
 
 /**
- * struct wil_ctx - software context for Vring descriptor
+ * struct wil_ctx - software context for ring descriptor
  */
 struct wil_ctx {
 	struct sk_buff *skb;
@@ -455,22 +463,59 @@ struct wil_ctx {
 	u8 mapped_as;
 };
 
-union vring_desc;
+struct wil_desc_ring_rx_swtail { /* relevant for enhanced DMA only */
+	u32 *va;
+	dma_addr_t pa;
+};
 
-struct vring {
+/**
+ * A general ring structure, used for RX and TX.
+ * In legacy DMA it represents the vring,
+ * In enahnced DMA it represents the descriptor ring (vrings are handled by FW)
+ */
+struct wil_ring {
 	dma_addr_t pa;
-	volatile union vring_desc *va; /* vring_desc[size], WriteBack by DMA */
-	u16 size; /* number of vring_desc elements */
+	volatile union wil_ring_desc *va;
+	u16 size; /* number of wil_ring_desc elements */
 	u32 swtail;
 	u32 swhead;
 	u32 hwtail; /* write here to inform hw */
 	struct wil_ctx *ctx; /* ctx[size] - software context */
+	struct wil_desc_ring_rx_swtail edma_rx_swtail;
+	bool is_rx;
 };
 
 /**
- * Additional data for Tx Vring
+ * Additional data for Rx ring.
+ * Used for enhanced DMA RX chaining.
  */
-struct vring_tx_data {
+struct wil_ring_rx_data {
+	/* the skb being assembled */
+	struct sk_buff *skb;
+	/* true if we are skipping a bad fragmented packet */
+	bool skipping;
+	u16 buff_size;
+};
+
+/**
+ * Status ring structure, used for enhanced DMA completions for RX and TX.
+ */
+struct wil_status_ring {
+	dma_addr_t pa;
+	void *va; /* pointer to ring_[tr]x_status elements */
+	u16 size; /* number of status elements */
+	size_t elem_size; /* status element size in bytes */
+	u32 swhead;
+	u32 hwtail; /* write here to inform hw */
+	bool is_rx;
+	u8 desc_rdy_pol; /* Expected descriptor ready bit polarity */
+	struct wil_ring_rx_data rx_data;
+};
+
+/**
+ * Additional data for Tx ring
+ */
+struct wil_ring_tx_data {
 	bool dot1x_open;
 	int enabled;
 	cycles_t idle, last_idle, begin;
@@ -573,6 +618,9 @@ struct wil_net_stats {
 	unsigned long	rx_short_frame;
 	unsigned long	rx_large_frame;
 	unsigned long	rx_replay;
+	unsigned long	rx_mic_error; /* eDMA specific */
+	unsigned long	rx_key_error; /* eDMA specific */
+	unsigned long	rx_amsdu_error; /* eDMA specific */
 	u16 last_mcs_rx;
 	u64 rx_per_mcs[WIL_MCS_MAX + 1];
 };
@@ -690,7 +738,7 @@ struct wil6210_vif {
 	u8 hidden_ssid; /* relevant in AP mode */
 	u32 ap_isolate; /* no intra-BSS communication */
 	bool pbss;
-	int bcast_vring;
+	int bcast_ring;
 	struct cfg80211_bss *bss; /* connected bss, relevant in STA mode */
 	int locally_generated_disc; /* relevant in STA mode */
 	struct timer_list connect_timer;
@@ -706,6 +754,31 @@ struct wil6210_vif {
 	int net_queue_stopped; /* netif_tx_stop_all_queues invoked */
 };
 
+/**
+ * RX buffer allocated for enhanced DMA RX descriptors
+ */
+struct wil_rx_buff {
+	struct sk_buff *skb;
+	struct list_head list;
+	int id;
+};
+
+/**
+ * During Rx completion processing, the driver extracts a buffer ID which
+ * is used as an index to the rx_buff_mgmt.buff_arr array and then the SKB
+ * is given to the network stack and the buffer is moved from the 'active'
+ * list to the 'free' list.
+ * During Rx refill, SKBs are attached to free buffers and moved to the
+ * 'active' list.
+ */
+struct wil_rx_buff_mgmt {
+	struct wil_rx_buff *buff_arr;
+	size_t size; /* number of items in buff_arr */
+	struct list_head active;
+	struct list_head free;
+	unsigned long free_list_empty_cnt; /* statistics */
+};
+
 struct wil6210_priv {
 	struct pci_dev *pdev;
 	u32 bar_size;
@@ -770,14 +843,17 @@ struct wil6210_priv {
 	struct net_device napi_ndev; /* dummy net_device serving all VIFs */
 
 	/* DMA related */
-	struct vring vring_rx;
+	struct wil_ring ring_rx;
 	unsigned int rx_buf_len;
-	struct vring vring_tx[WIL6210_MAX_TX_RINGS];
-	struct vring_tx_data vring_tx_data[WIL6210_MAX_TX_RINGS];
-	u8 vring2cid_tid[WIL6210_MAX_TX_RINGS][2]; /* [0] - CID, [1] - TID */
+	struct wil_ring ring_tx[WIL6210_MAX_TX_RINGS];
+	struct wil_ring_tx_data ring_tx_data[WIL6210_MAX_TX_RINGS];
+	struct wil_status_ring srings[WIL6210_MAX_STATUS_RINGS];
+	int num_rx_status_rings;
+	u8 ring2cid_tid[WIL6210_MAX_TX_RINGS][2]; /* [0] - CID, [1] - TID */
 	struct wil_sta_info sta[WIL6210_MAX_CID];
-	u32 vring_idle_trsh; /* HW fetches up to 16 descriptors at once  */
+	u32 ring_idle_trsh; /* HW fetches up to 16 descriptors at once  */
 	u32 dma_addr_size; /* indicates dma addr size */
+	struct wil_rx_buff_mgmt rx_buff_mgmt;
 
 	struct mutex mutex; /* for wil6210_priv access in wil_{up|down} */
 	/* statistics */
@@ -999,7 +1075,7 @@ int wmi_add_cipher_key(struct wil6210_vif *vif, u8 key_index,
 		       int key_usage);
 int wmi_echo(struct wil6210_priv *wil);
 int wmi_set_ie(struct wil6210_vif *vif, u8 type, u16 ie_len, const void *ie);
-int wmi_rx_chain_add(struct wil6210_priv *wil, struct vring *vring);
+int wmi_rx_chain_add(struct wil6210_priv *wil, struct wil_ring *vring);
 int wmi_rxon(struct wil6210_priv *wil, bool on);
 int wmi_get_temperature(struct wil6210_priv *wil, u32 *t_m, u32 *t_r);
 int wmi_disconnect_sta(struct wil6210_vif *vif, const u8 *mac,
@@ -1098,7 +1174,7 @@ void wil_rx_fini(struct wil6210_priv *wil);
 /* TX API */
 int wil_vring_init_tx(struct wil6210_vif *vif, int id, int size,
 		      int cid, int tid);
-void wil_vring_fini_tx(struct wil6210_priv *wil, int id);
+void wil_ring_fini_tx(struct wil6210_priv *wil, int id);
 int wil_tx_init(struct wil6210_vif *vif, int cid);
 int wil_vring_init_bcast(struct wil6210_vif *vif, int id, int size);
 int wil_bcast_init(struct wil6210_vif *vif);
@@ -1106,9 +1182,9 @@ void wil_bcast_fini(struct wil6210_vif *vif);
 void wil_bcast_fini_all(struct wil6210_priv *wil);
 
 void wil_update_net_queues(struct wil6210_priv *wil, struct wil6210_vif *vif,
-			   struct vring *vring, bool should_stop);
+			   struct wil_ring *ring, bool should_stop);
 void wil_update_net_queues_bh(struct wil6210_priv *wil, struct wil6210_vif *vif,
-			      struct vring *vring, bool check_stop);
+			      struct wil_ring *ring, bool check_stop);
 netdev_tx_t wil_start_xmit(struct sk_buff *skb, struct net_device *ndev);
 int wil_tx_complete(struct wil6210_vif *vif, int ringid);
 void wil6210_unmask_irq_tx(struct wil6210_priv *wil);