diff --git a/drivers/net/wireless/wl12xx/acx.c b/drivers/net/wireless/wl12xx/acx.c
index a3db755..50676b3 100644
--- a/drivers/net/wireless/wl12xx/acx.c
+++ b/drivers/net/wireless/wl12xx/acx.c
@@ -1019,6 +1019,32 @@
 	return ret;
 }
 
+int wl1271_acx_host_if_cfg_bitmap(struct wl1271 *wl, u32 host_cfg_bitmap)
+{
+	struct wl1271_acx_host_config_bitmap *bitmap_conf;
+	int ret;
+
+	bitmap_conf = kzalloc(sizeof(*bitmap_conf), GFP_KERNEL);
+	if (!bitmap_conf) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	bitmap_conf->host_cfg_bitmap = cpu_to_le32(host_cfg_bitmap);
+
+	ret = wl1271_cmd_configure(wl, ACX_HOST_IF_CFG_BITMAP,
+				   bitmap_conf, sizeof(*bitmap_conf));
+	if (ret < 0) {
+		wl1271_warning("wl1271 bitmap config opt failed: %d", ret);
+		goto out;
+	}
+
+out:
+	kfree(bitmap_conf);
+
+	return ret;
+}
+
 int wl1271_acx_init_mem_config(struct wl1271 *wl)
 {
 	int ret;
diff --git a/drivers/net/wireless/wl12xx/acx.h b/drivers/net/wireless/wl12xx/acx.h
index dd19b01..0a40cae 100644
--- a/drivers/net/wireless/wl12xx/acx.h
+++ b/drivers/net/wireless/wl12xx/acx.h
@@ -939,6 +939,16 @@
 	u8 padding;
 } __packed;
 
+#define HOST_IF_CFG_RX_FIFO_ENABLE     BIT(0)
+#define HOST_IF_CFG_TX_EXTRA_BLKS_SWAP BIT(1)
+#define HOST_IF_CFG_TX_PAD_TO_SDIO_BLK BIT(3)
+
+struct wl1271_acx_host_config_bitmap {
+	struct acx_header header;
+
+	__le32 host_cfg_bitmap;
+} __packed;
+
 enum {
 	WL1271_ACX_TRIG_TYPE_LEVEL = 0,
 	WL1271_ACX_TRIG_TYPE_EDGE,
@@ -1275,6 +1285,7 @@
 int wl1271_acx_ap_mem_cfg(struct wl1271 *wl);
 int wl1271_acx_sta_mem_cfg(struct wl1271 *wl);
 int wl1271_acx_init_mem_config(struct wl1271 *wl);
+int wl1271_acx_host_if_cfg_bitmap(struct wl1271 *wl, u32 host_cfg_bitmap);
 int wl1271_acx_init_rx_interrupt(struct wl1271 *wl);
 int wl1271_acx_smart_reflex(struct wl1271 *wl);
 int wl1271_acx_bet_enable(struct wl1271 *wl, bool enable);
diff --git a/drivers/net/wireless/wl12xx/init.c b/drivers/net/wireless/wl12xx/init.c
index 6072fe4..34c4108 100644
--- a/drivers/net/wireless/wl12xx/init.c
+++ b/drivers/net/wireless/wl12xx/init.c
@@ -31,6 +31,7 @@
 #include "cmd.h"
 #include "reg.h"
 #include "tx.h"
+#include "io.h"
 
 int wl1271_sta_init_templates_config(struct wl1271 *wl)
 {
@@ -504,6 +505,27 @@
 	return ret;
 }
 
+int wl1271_chip_specific_init(struct wl1271 *wl)
+{
+	int ret = 0;
+
+	if (wl->chip.id == CHIP_ID_1283_PG20) {
+		u32 host_cfg_bitmap = HOST_IF_CFG_RX_FIFO_ENABLE;
+
+		if (wl1271_set_block_size(wl))
+			/* Enable SDIO padding */
+			host_cfg_bitmap |= HOST_IF_CFG_TX_PAD_TO_SDIO_BLK;
+
+		/* Must be before wl1271_acx_init_mem_config() */
+		ret = wl1271_acx_host_if_cfg_bitmap(wl, host_cfg_bitmap);
+		if (ret < 0)
+			goto out;
+	}
+out:
+	return ret;
+}
+
+
 int wl1271_hw_init(struct wl1271 *wl)
 {
 	struct conf_tx_ac_category *conf_ac;
@@ -519,6 +541,11 @@
 	if (ret < 0)
 		return ret;
 
+	/* Chip-specific init */
+	ret = wl1271_chip_specific_init(wl);
+	if (ret < 0)
+		return ret;
+
 	/* Mode specific init */
 	if (is_ap)
 		ret = wl1271_ap_hw_init(wl);
diff --git a/drivers/net/wireless/wl12xx/init.h b/drivers/net/wireless/wl12xx/init.h
index 3a8bd3f..4975270 100644
--- a/drivers/net/wireless/wl12xx/init.h
+++ b/drivers/net/wireless/wl12xx/init.h
@@ -31,6 +31,7 @@
 int wl1271_init_phy_config(struct wl1271 *wl);
 int wl1271_init_pta(struct wl1271 *wl);
 int wl1271_init_energy_detection(struct wl1271 *wl);
+int wl1271_chip_specific_init(struct wl1271 *wl);
 int wl1271_hw_init(struct wl1271 *wl);
 
 #endif
diff --git a/drivers/net/wireless/wl12xx/io.c b/drivers/net/wireless/wl12xx/io.c
index d557f73..aa40c98 100644
--- a/drivers/net/wireless/wl12xx/io.c
+++ b/drivers/net/wireless/wl12xx/io.c
@@ -43,6 +43,16 @@
 #define OCP_STATUS_REQ_FAILED 0x20000
 #define OCP_STATUS_RESP_ERROR 0x30000
 
+bool wl1271_set_block_size(struct wl1271 *wl)
+{
+	if (wl->if_ops->set_block_size) {
+		wl->if_ops->set_block_size(wl);
+		return true;
+	}
+
+	return false;
+}
+
 void wl1271_disable_interrupts(struct wl1271 *wl)
 {
 	wl->if_ops->disable_irq(wl);
diff --git a/drivers/net/wireless/wl12xx/io.h b/drivers/net/wireless/wl12xx/io.h
index c1aac82..84454f6 100644
--- a/drivers/net/wireless/wl12xx/io.h
+++ b/drivers/net/wireless/wl12xx/io.h
@@ -169,5 +169,6 @@
 struct ieee80211_hw *wl1271_alloc_hw(void);
 int wl1271_free_hw(struct wl1271 *wl);
 irqreturn_t wl1271_irq(int irq, void *data);
+bool wl1271_set_block_size(struct wl1271 *wl);
 
 #endif
diff --git a/drivers/net/wireless/wl12xx/main.c b/drivers/net/wireless/wl12xx/main.c
index b0c4935..f24906f 100644
--- a/drivers/net/wireless/wl12xx/main.c
+++ b/drivers/net/wireless/wl12xx/main.c
@@ -450,6 +450,11 @@
 	if (ret < 0)
 		return ret;
 
+	/* Chip-specific initializations */
+	ret = wl1271_chip_specific_init(wl);
+	if (ret < 0)
+		return ret;
+
 	ret = wl1271_sta_init_templates_config(wl);
 	if (ret < 0)
 		return ret;
@@ -1335,6 +1340,7 @@
 	memset(wl->ap_hlid_map, 0, sizeof(wl->ap_hlid_map));
 	wl->ap_fw_ps_map = 0;
 	wl->ap_ps_map = 0;
+	wl->block_size = 0;
 
 	for (i = 0; i < NUM_TX_QUEUES; i++)
 		wl->tx_blocks_freed[i] = 0;
@@ -3458,6 +3464,7 @@
 	wl->ap_ps_map = 0;
 	wl->ap_fw_ps_map = 0;
 	wl->quirks = 0;
+	wl->block_size = 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/tx.c b/drivers/net/wireless/wl12xx/tx.c
index 5e9ef7d..e296f0a 100644
--- a/drivers/net/wireless/wl12xx/tx.c
+++ b/drivers/net/wireless/wl12xx/tx.c
@@ -132,6 +132,7 @@
 {
 	struct wl1271_tx_hw_descr *desc;
 	u32 total_len = skb->len + sizeof(struct wl1271_tx_hw_descr) + extra;
+	u32 len;
 	u32 total_blocks;
 	int id, ret = -EBUSY;
 
@@ -145,14 +146,20 @@
 
 	/* approximate the number of blocks required for this packet
 	   in the firmware */
-	total_blocks = total_len + TX_HW_BLOCK_SIZE - 1;
-	total_blocks = total_blocks / TX_HW_BLOCK_SIZE + TX_HW_BLOCK_SPARE;
+	if (wl->block_size)
+		len = ALIGN(total_len, wl->block_size);
+	else
+		len = total_len;
+
+	total_blocks = (len + TX_HW_BLOCK_SIZE - 1) / TX_HW_BLOCK_SIZE +
+		TX_HW_BLOCK_SPARE;
+
 	if (total_blocks <= wl->tx_blocks_available) {
 		desc = (struct wl1271_tx_hw_descr *)skb_push(
 			skb, total_len - skb->len);
 
-		desc->extra_mem_blocks = TX_HW_BLOCK_SPARE;
-		desc->total_mem_blocks = total_blocks;
+		desc->wl127x_mem.extra_blocks = TX_HW_BLOCK_SPARE;
+		desc->wl127x_mem.total_mem_blocks = total_blocks;
 		desc->id = id;
 
 		wl->tx_blocks_available -= total_blocks;
@@ -178,7 +185,7 @@
 {
 	struct timespec ts;
 	struct wl1271_tx_hw_descr *desc;
-	int pad, ac, rate_idx;
+	int aligned_len, ac, rate_idx;
 	s64 hosttime;
 	u16 tx_attr;
 
@@ -237,20 +244,32 @@
 	tx_attr |= rate_idx << TX_HW_ATTR_OFST_RATE_POLICY;
 	desc->reserved = 0;
 
-	/* align the length (and store in terms of words) */
-	pad = ALIGN(skb->len, WL1271_TX_ALIGN_TO);
-	desc->length = cpu_to_le16(pad >> 2);
+	if (wl->block_size) {
+		aligned_len = ALIGN(skb->len, wl->block_size);
 
-	/* calculate number of padding bytes */
-	pad = pad - skb->len;
-	tx_attr |= pad << TX_HW_ATTR_OFST_LAST_WORD_PAD;
+		desc->wl128x_mem.extra_bytes = aligned_len - skb->len;
+		desc->length = cpu_to_le16(aligned_len >> 2);
+	} else {
+		int pad;
+
+		/* align the length (and store in terms of words) */
+		aligned_len = ALIGN(skb->len, WL1271_TX_ALIGN_TO);
+		desc->length = cpu_to_le16(aligned_len >> 2);
+
+		/* calculate number of padding bytes */
+		pad = aligned_len - skb->len;
+		tx_attr |= pad << TX_HW_ATTR_OFST_LAST_WORD_PAD;
+
+		wl1271_debug(DEBUG_TX, "tx_fill_hdr: padding: %d", pad);
+	}
 
 	desc->tx_attr = cpu_to_le16(tx_attr);
 
-	wl1271_debug(DEBUG_TX, "tx_fill_hdr: pad: %d hlid: %d "
-		"tx_attr: 0x%x len: %d life: %d mem: %d", pad, desc->hlid,
-		le16_to_cpu(desc->tx_attr), le16_to_cpu(desc->length),
-		le16_to_cpu(desc->life_time), desc->total_mem_blocks);
+	wl1271_debug(DEBUG_TX, "tx_fill_hdr: hlid: %d tx_attr: 0x%x "
+		     "len: %d life: %d mem: %d",
+		     desc->hlid, le16_to_cpu(desc->tx_attr),
+		     le16_to_cpu(desc->length),	le16_to_cpu(desc->life_time),
+		     desc->wl127x_mem.total_mem_blocks);
 }
 
 /* caller must hold wl->mutex */
@@ -305,11 +324,18 @@
 	wl1271_tx_fill_hdr(wl, skb, extra, info, hlid);
 
 	/*
-	 * The length of each packet is stored in terms of words. Thus, we must
-	 * pad the skb data to make sure its length is aligned.
-	 * The number of padding bytes is computed and set in wl1271_tx_fill_hdr
+	 * The length of each packet is stored in terms of
+	 * words. Thus, we must pad the skb data to make sure its
+	 * length is aligned.  The number of padding bytes is computed
+	 * and set in wl1271_tx_fill_hdr.
+	 * In special cases, we want to align to a specific block size
+	 * (eg. for wl128x with SDIO we align to 256).
 	 */
-	total_len = ALIGN(skb->len, WL1271_TX_ALIGN_TO);
+	if (wl->block_size)
+		total_len = ALIGN(skb->len, wl->block_size);
+	else
+		total_len = ALIGN(skb->len, WL1271_TX_ALIGN_TO);
+
 	memcpy(wl->aggr_buf + buf_offset, skb->data, skb->len);
 	memset(wl->aggr_buf + buf_offset + skb->len, 0, total_len - skb->len);
 
diff --git a/drivers/net/wireless/wl12xx/tx.h b/drivers/net/wireless/wl12xx/tx.h
index 02f07fa..e313177 100644
--- a/drivers/net/wireless/wl12xx/tx.h
+++ b/drivers/net/wireless/wl12xx/tx.h
@@ -55,20 +55,48 @@
 #define WL1271_TX_ALIGN_TO 4
 #define WL1271_TKIP_IV_SPACE 4
 
+struct wl127x_tx_mem {
+	/*
+	 * Number of extra memory blocks to allocate for this packet
+	 * in addition to the number of blocks derived from the packet
+	 * length.
+	 */
+	u8 extra_blocks;
+	/*
+	 * Total number of memory blocks allocated by the host for
+	 * this packet. Must be equal or greater than the actual
+	 * blocks number allocated by HW.
+	 */
+	u8 total_mem_blocks;
+} __packed;
+
+struct wl128x_tx_mem {
+	/*
+	 * Total number of memory blocks allocated by the host for
+	 * this packet.
+	 */
+	u8 total_mem_blocks;
+	/*
+	 * Number of extra bytes, at the end of the frame. the host
+	 * uses this padding to complete each frame to integer number
+	 * of SDIO blocks.
+	 */
+	u8 extra_bytes;
+} __packed;
+
 struct wl1271_tx_hw_descr {
 	/* Length of packet in words, including descriptor+header+data */
 	__le16 length;
-	/* Number of extra memory blocks to allocate for this packet in
-	   addition to the number of blocks derived from the packet length */
-	u8 extra_mem_blocks;
-	/* Total number of memory blocks allocated by the host for this packet.
-	   Must be equal or greater than the actual blocks number allocated by
-	   HW!! */
-	u8 total_mem_blocks;
+	union {
+		struct wl127x_tx_mem wl127x_mem;
+		struct wl128x_tx_mem wl128x_mem;
+	} __packed;
 	/* Device time (in us) when the packet arrived to the driver */
 	__le32 start_time;
-	/* Max delay in TUs until transmission. The last device time the
-	   packet can be transmitted is: startTime+(1024*LifeTime) */
+	/*
+	 * Max delay in TUs until transmission. The last device time the
+	 * packet can be transmitted is: start_time + (1024 * life_time)
+	 */
 	__le16 life_time;
 	/* Bitwise fields - see TX_ATTR... definitions above. */
 	__le16 tx_attr;
diff --git a/drivers/net/wireless/wl12xx/wl12xx.h b/drivers/net/wireless/wl12xx/wl12xx.h
index a2e899d..959b338 100644
--- a/drivers/net/wireless/wl12xx/wl12xx.h
+++ b/drivers/net/wireless/wl12xx/wl12xx.h
@@ -303,6 +303,7 @@
 	struct device* (*dev)(struct wl1271 *wl);
 	void (*enable_irq)(struct wl1271 *wl);
 	void (*disable_irq)(struct wl1271 *wl);
+	void (*set_block_size) (struct wl1271 *wl);
 };
 
 #define MAX_NUM_KEYS 14
@@ -533,6 +534,8 @@
 	bool ba_support;
 	u8 ba_rx_bitmap;
 
+	u32 block_size;
+
 	/*
 	 * AP-mode - links indexed by HLID. The global and broadcast links
 	 * are always active.