wl12xx: Do end-of-transactions transfers only if needed

On newer hardware revisions, there is no need to write the host's
counter at the end of a RX transaction. The same applies to writing the
number of packets at the end of a TX transaction.

It is generally a good idea to avoid unnecessary SDIO/SPI transfers.
Throughput and CPU usage are improved when avoiding these.

Send the host's RX counter and the TX packet count only if needed, based
on the hardware revision.

[Changed WL12XX_QUIRK_END_OF_TRANSACTION to use BIT(0) -- Luca]

Signed-off-by: Ido Yariv <ido@wizery.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
Reviewed-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

6 files changed, 32 insertions, 3 deletions

diff --git a/drivers/net/wireless/wl12xx/boot.c b/drivers/net/wireless/wl12xx/boot.c
index 1ffbad67d2d8..6934dffd5174 100644
--- a/drivers/net/wireless/wl12xx/boot.c
+++ b/drivers/net/wireless/wl12xx/boot.c
@@ -488,6 +488,9 @@ static void wl1271_boot_hw_version(struct wl1271 *wl)
         fuse = (fuse & PG_VER_MASK) >> PG_VER_OFFSET;
 
         wl->hw_pg_ver = (s8)fuse;
+
+        if (((wl->hw_pg_ver & PG_MAJOR_VER_MASK) >> PG_MAJOR_VER_OFFSET) < 3)
+                wl->quirks |= WL12XX_QUIRK_END_OF_TRANSACTION;
 }
 
 /* uploads NVS and firmware */
diff --git a/drivers/net/wireless/wl12xx/boot.h b/drivers/net/wireless/wl12xx/boot.h
index d67dcffa31eb..17229b86fc71 100644
--- a/drivers/net/wireless/wl12xx/boot.h
+++ b/drivers/net/wireless/wl12xx/boot.h
@@ -59,6 +59,11 @@ struct wl1271_static_data {
 #define PG_VER_MASK          0x3c
 #define PG_VER_OFFSET        2
 
+#define PG_MAJOR_VER_MASK    0x3
+#define PG_MAJOR_VER_OFFSET  0x0
+#define PG_MINOR_VER_MASK    0xc
+#define PG_MINOR_VER_OFFSET  0x2
+
 #define CMD_MBOX_ADDRESS     0x407B4
 
 #define POLARITY_LOW         BIT(1)
diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c
index 65e8a0cc92d0..ba34ac3a440d 100644
--- a/drivers/net/wireless/wl12xx/main.c
+++ b/drivers/net/wireless/wl12xx/main.c
@@ -3404,6 +3404,7 @@ struct ieee80211_hw *wl1271_alloc_hw(void)
         wl->last_tx_hlid = 0;
         wl->ap_ps_map = 0;
         wl->ap_fw_ps_map = 0;
+        wl->quirks = 0;
 
         memset(wl->tx_frames_map, 0, sizeof(wl->tx_frames_map));
         for (i = 0; i < ACX_TX_DESCRIPTORS; i++)
diff --git a/drivers/net/wireless/wl12xx/rx.c b/drivers/net/wireless/wl12xx/rx.c
index 3d13d7a83ea1..4e7a3b311321 100644
--- a/drivers/net/wireless/wl12xx/rx.c
+++ b/drivers/net/wireless/wl12xx/rx.c
@@ -198,7 +198,13 @@ void wl1271_rx(struct wl1271 *wl, struct wl1271_fw_common_status *status)
                         pkt_offset += pkt_length;
                 }
         }
-        wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
+
+        /*
+         * Write the driver's packet counter to the FW. This is only required
+         * for older hardware revisions
+         */
+        if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
+                wl1271_write32(wl, RX_DRIVER_COUNTER_ADDRESS, wl->rx_counter);
 }
 
 void wl1271_set_default_filters(struct wl1271 *wl)
diff --git a/drivers/net/wireless/wl12xx/tx.c b/drivers/net/wireless/wl12xx/tx.c
index 37d354ddd58e..455954edf83e 100644
--- a/drivers/net/wireless/wl12xx/tx.c
+++ b/drivers/net/wireless/wl12xx/tx.c
@@ -506,8 +506,14 @@ out_ack:
                 sent_packets = true;
         }
         if (sent_packets) {
-                /* interrupt the firmware with the new packets */
-                wl1271_write32(wl, WL1271_HOST_WR_ACCESS, wl->tx_packets_count);
+                /*
+                 * Interrupt the firmware with the new packets. This is only
+                 * required for older hardware revisions
+                 */
+                if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
+                        wl1271_write32(wl, WL1271_HOST_WR_ACCESS,
+                                       wl->tx_packets_count);
+
                 wl1271_handle_tx_low_watermark(wl);
         }
 
diff --git a/drivers/net/wireless/wl12xx/wl12xx.h b/drivers/net/wireless/wl12xx/wl12xx.h
index 7132bc7dd2cf..ea1eee7895cf 100644
--- a/drivers/net/wireless/wl12xx/wl12xx.h
+++ b/drivers/net/wireless/wl12xx/wl12xx.h
@@ -535,6 +535,9 @@ struct wl1271 {
 
         /* AP-mode - a bitmap of links currently in PS mode in mac80211 */
         unsigned long ap_ps_map;
+
+        /* Quirks of specific hardware revisions */
+        unsigned int quirks;
 };
 
 struct wl1271_station {
@@ -562,4 +565,9 @@ int wl1271_plt_stop(struct wl1271 *wl);
 #define HW_BG_RATES_MASK        0xffff
 #define HW_HT_RATES_OFFSET      16
 
+/* Quirks */
+
+/* Each RX/TX transaction requires an end-of-transaction transfer */
+#define WL12XX_QUIRK_END_OF_TRANSACTION BIT(0)
+
 #endif