[PATCH] bcm43xx: make PIO mode usable

This patch fixes PIO mode on the softmac bcm43xx
driver. (A dscape patch will follow).
It mainly fixes endianess issues.
This patch is tested on PowerPC32 and i386.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 84 insertions, 32 deletions

diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_dma.h b/drivers/net/wireless/bcm43xx/bcm43xx_dma.h
index 2d520e4b0276..b7d77638ba8c 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_dma.h
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_dma.h
@@ -213,6 +213,14 @@ static inline
 void bcm43xx_dma_rx(struct bcm43xx_dmaring *ring)
 {
 }
+static inline
+void bcm43xx_dma_tx_suspend(struct bcm43xx_dmaring *ring)
+{
+}
+static inline
+void bcm43xx_dma_tx_resume(struct bcm43xx_dmaring *ring)
+{
+}
 
 #endif /* CONFIG_BCM43XX_DMA */
 #endif /* BCM43xx_DMA_H_ */
diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_pio.c b/drivers/net/wireless/bcm43xx/bcm43xx_pio.c
index c59ddd40680d..0aa1bd269a25 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_pio.c
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_pio.c
@@ -27,6 +27,7 @@
 #include "bcm43xx_pio.h"
 #include "bcm43xx_main.h"
 #include "bcm43xx_xmit.h"
+#include "bcm43xx_power.h"
 
 #include <linux/delay.h>
 
@@ -44,10 +45,10 @@ static void tx_octet(struct bcm43xx_pioqueue *queue,
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA,
 				  octet);
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL,
-				  BCM43xx_PIO_TXCTL_WRITEHI);
+				  BCM43xx_PIO_TXCTL_WRITELO);
 	} else {
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL,
-				  BCM43xx_PIO_TXCTL_WRITEHI);
+				  BCM43xx_PIO_TXCTL_WRITELO);
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA,
 				  octet);
 	}
@@ -103,7 +104,7 @@ static void tx_complete(struct bcm43xx_pioqueue *queue,
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXDATA,
 				  skb->data[skb->len - 1]);
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL,
-				  BCM43xx_PIO_TXCTL_WRITEHI |
+				  BCM43xx_PIO_TXCTL_WRITELO |
 				  BCM43xx_PIO_TXCTL_COMPLETE);
 	} else {
 		bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL,
@@ -112,9 +113,10 @@ static void tx_complete(struct bcm43xx_pioqueue *queue,
 }
 
 static u16 generate_cookie(struct bcm43xx_pioqueue *queue,
-			   int packetindex)
+			   struct bcm43xx_pio_txpacket *packet)
 {
 	u16 cookie = 0x0000;
+	int packetindex;
 
 	/* We use the upper 4 bits for the PIO
 	 * controller ID and the lower 12 bits
@@ -135,6 +137,7 @@ static u16 generate_cookie(struct bcm43xx_pioqueue *queue,
 	default:
 		assert(0);
 	}
+	packetindex = pio_txpacket_getindex(packet);
 	assert(((u16)packetindex & 0xF000) == 0x0000);
 	cookie |= (u16)packetindex;
 
@@ -184,7 +187,7 @@ static void pio_tx_write_fragment(struct bcm43xx_pioqueue *queue,
 	bcm43xx_generate_txhdr(queue->bcm,
 			       &txhdr, skb->data, skb->len,
 			       (packet->xmitted_frags == 0),
-			       generate_cookie(queue, pio_txpacket_getindex(packet)));
+			       generate_cookie(queue, packet));
 
 	tx_start(queue);
 	octets = skb->len + sizeof(txhdr);
@@ -241,7 +244,7 @@ static int pio_tx_packet(struct bcm43xx_pio_txpacket *packet)
 		queue->tx_devq_packets++;
 		queue->tx_devq_used += octets;
 
-		assert(packet->xmitted_frags <= packet->txb->nr_frags);
+		assert(packet->xmitted_frags < packet->txb->nr_frags);
 		packet->xmitted_frags++;
 		packet->xmitted_octets += octets;
 	}
@@ -257,8 +260,14 @@ static void tx_tasklet(unsigned long d)
 	unsigned long flags;
 	struct bcm43xx_pio_txpacket *packet, *tmp_packet;
 	int err;
+	u16 txctl;
 
 	bcm43xx_lock_mmio(bcm, flags);
+
+	txctl = bcm43xx_pio_read(queue, BCM43xx_PIO_TXCTL);
+	if (txctl & BCM43xx_PIO_TXCTL_SUSPEND)
+		goto out_unlock;
+
 	list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list) {
 		assert(packet->xmitted_frags < packet->txb->nr_frags);
 		if (packet->xmitted_frags == 0) {
@@ -288,6 +297,7 @@ static void tx_tasklet(unsigned long d)
 	next_packet:
 		continue;
 	}
+out_unlock:
 	bcm43xx_unlock_mmio(bcm, flags);
 }
 
@@ -330,12 +340,19 @@ struct bcm43xx_pioqueue * bcm43xx_setup_pioqueue(struct bcm43xx_private *bcm,
 		     (unsigned long)queue);
 
 	value = bcm43xx_read32(bcm, BCM43xx_MMIO_STATUS_BITFIELD);
-	value |= BCM43xx_SBF_XFER_REG_BYTESWAP;
+	value &= ~BCM43xx_SBF_XFER_REG_BYTESWAP;
 	bcm43xx_write32(bcm, BCM43xx_MMIO_STATUS_BITFIELD, value);
 
 	qsize = bcm43xx_read16(bcm, queue->mmio_base + BCM43xx_PIO_TXQBUFSIZE);
+	if (qsize == 0) {
+		printk(KERN_ERR PFX "ERROR: This card does not support PIO "
+				    "operation mode. Please use DMA mode "
+				    "(module parameter pio=0).\n");
+		goto err_freequeue;
+	}
 	if (qsize <= BCM43xx_PIO_TXQADJUST) {
-		printk(KERN_ERR PFX "PIO tx device-queue too small (%u)\n", qsize);
+		printk(KERN_ERR PFX "PIO tx device-queue too small (%u)\n",
+		       qsize);
 		goto err_freequeue;
 	}
 	qsize -= BCM43xx_PIO_TXQADJUST;
@@ -444,15 +461,10 @@ int bcm43xx_pio_tx(struct bcm43xx_private *bcm,
 {
 	struct bcm43xx_pioqueue *queue = bcm43xx_current_pio(bcm)->queue1;
 	struct bcm43xx_pio_txpacket *packet;
-	u16 tmp;
 
 	assert(!queue->tx_suspended);
 	assert(!list_empty(&queue->txfree));
 
-	tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_TXCTL);
-	if (tmp & BCM43xx_PIO_TXCTL_SUSPEND)
-		return -EBUSY;
-
 	packet = list_entry(queue->txfree.next, struct bcm43xx_pio_txpacket, list);
 	packet->txb = txb;
 	packet->xmitted_frags = 0;
@@ -462,7 +474,7 @@ int bcm43xx_pio_tx(struct bcm43xx_private *bcm,
 	assert(queue->nr_txfree < BCM43xx_PIO_MAXTXPACKETS);
 
 	/* Suspend TX, if we are out of packets in the "free" queue. */
-	if (unlikely(list_empty(&queue->txfree))) {
+	if (list_empty(&queue->txfree)) {
 		netif_stop_queue(queue->bcm->net_dev);
 		queue->tx_suspended = 1;
 	}
@@ -480,15 +492,15 @@ void bcm43xx_pio_handle_xmitstatus(struct bcm43xx_private *bcm,
 
 	queue = parse_cookie(bcm, status->cookie, &packet);
 	assert(queue);
-//TODO
-if (!queue)
-return;
+
 	free_txpacket(packet, 1);
-	if (unlikely(queue->tx_suspended)) {
+	if (queue->tx_suspended) {
 		queue->tx_suspended = 0;
 		netif_wake_queue(queue->bcm->net_dev);
 	}
-	/* If there are packets on the txqueue, poke the tasklet. */
+	/* If there are packets on the txqueue, poke the tasklet
+	 * to transmit them.
+	 */
 	if (!list_empty(&queue->txqueue))
 		tasklet_schedule(&queue->txtask);
 }
@@ -519,12 +531,9 @@ void bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue)
 	int i, preamble_readwords;
 	struct sk_buff *skb;
 
-return;
 	tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXCTL);
-	if (!(tmp & BCM43xx_PIO_RXCTL_DATAAVAILABLE)) {
-		dprintkl(KERN_ERR PFX "PIO RX: No data available\n");//TODO: remove this printk.
+	if (!(tmp & BCM43xx_PIO_RXCTL_DATAAVAILABLE))
 		return;
-	}
 	bcm43xx_pio_write(queue, BCM43xx_PIO_RXCTL,
 			  BCM43xx_PIO_RXCTL_DATAAVAILABLE);
 
@@ -538,8 +547,7 @@ return;
 	return;
 data_ready:
 
-//FIXME: endianess in this function.
-	len = le16_to_cpu(bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA));
+	len = bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA);
 	if (unlikely(len > 0x700)) {
 		pio_rx_error(queue, 0, "len > 0x700");
 		return;
@@ -555,7 +563,7 @@ data_ready:
 		preamble_readwords = 18 / sizeof(u16);
 	for (i = 0; i < preamble_readwords; i++) {
 		tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA);
-		preamble[i + 1] = cpu_to_be16(tmp);//FIXME?
+		preamble[i + 1] = cpu_to_le16(tmp);
 	}
 	rxhdr = (struct bcm43xx_rxhdr *)preamble;
 	rxflags2 = le16_to_cpu(rxhdr->flags2);
@@ -591,16 +599,40 @@ data_ready:
 	}
 	skb_put(skb, len);
 	for (i = 0; i < len - 1; i += 2) {
-		tmp = cpu_to_be16(bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA));
-		*((u16 *)(skb->data + i)) = tmp;
+		tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA);
+		*((u16 *)(skb->data + i)) = cpu_to_le16(tmp);
 	}
 	if (len % 2) {
 		tmp = bcm43xx_pio_read(queue, BCM43xx_PIO_RXDATA);
 		skb->data[len - 1] = (tmp & 0x00FF);
+/* The specs say the following is required, but
+ * it is wrong and corrupts the PLCP. If we don't do
+ * this, the PLCP seems to be correct. So ifdef it out for now.
+ */
+#if 0
 		if (rxflags2 & BCM43xx_RXHDR_FLAGS2_TYPE2FRAME)
-			skb->data[0x20] = (tmp & 0xFF00) >> 8;
+			skb->data[2] = (tmp & 0xFF00) >> 8;
 		else
-			skb->data[0x1E] = (tmp & 0xFF00) >> 8;
+			skb->data[0] = (tmp & 0xFF00) >> 8;
+#endif
 	}
+	skb_trim(skb, len - IEEE80211_FCS_LEN);
 	bcm43xx_rx(queue->bcm, skb, rxhdr);
 }
+
+void bcm43xx_pio_tx_suspend(struct bcm43xx_pioqueue *queue)
+{
+	bcm43xx_power_saving_ctl_bits(queue->bcm, -1, 1);
+	bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL,
+			  bcm43xx_pio_read(queue, BCM43xx_PIO_TXCTL)
+			  | BCM43xx_PIO_TXCTL_SUSPEND);
+}
+
+void bcm43xx_pio_tx_resume(struct bcm43xx_pioqueue *queue)
+{
+	bcm43xx_pio_write(queue, BCM43xx_PIO_TXCTL,
+			  bcm43xx_pio_read(queue, BCM43xx_PIO_TXCTL)
+			  & ~BCM43xx_PIO_TXCTL_SUSPEND);
+	bcm43xx_power_saving_ctl_bits(queue->bcm, -1, -1);
+	tasklet_schedule(&queue->txtask);
+}
diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_pio.h b/drivers/net/wireless/bcm43xx/bcm43xx_pio.h
index 970627bc1769..dfc78209e3a3 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_pio.h
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_pio.h
@@ -14,8 +14,8 @@
 #define BCM43xx_PIO_RXCTL		0x08
 #define BCM43xx_PIO_RXDATA		0x0A
 
-#define BCM43xx_PIO_TXCTL_WRITEHI	(1 << 0)
-#define BCM43xx_PIO_TXCTL_WRITELO	(1 << 1)
+#define BCM43xx_PIO_TXCTL_WRITELO	(1 << 0)
+#define BCM43xx_PIO_TXCTL_WRITEHI	(1 << 1)
 #define BCM43xx_PIO_TXCTL_COMPLETE	(1 << 2)
 #define BCM43xx_PIO_TXCTL_INIT		(1 << 3)
 #define BCM43xx_PIO_TXCTL_SUSPEND	(1 << 7)
@@ -95,6 +95,7 @@ void bcm43xx_pio_write(struct bcm43xx_pioqueue *queue,
 		       u16 offset, u16 value)
 {
 	bcm43xx_write16(queue->bcm, queue->mmio_base + offset, value);
+	mmiowb();
 }
 
 
@@ -107,6 +108,9 @@ void bcm43xx_pio_handle_xmitstatus(struct bcm43xx_private *bcm,
 				   struct bcm43xx_xmitstatus *status);
 void bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue);
 
+void bcm43xx_pio_tx_suspend(struct bcm43xx_pioqueue *queue);
+void bcm43xx_pio_tx_resume(struct bcm43xx_pioqueue *queue);
+
 #else /* CONFIG_BCM43XX_PIO */
 
 static inline
@@ -133,6 +137,14 @@ static inline
 void bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue)
 {
 }
+static inline
+void bcm43xx_pio_tx_suspend(struct bcm43xx_pioqueue *queue)
+{
+}
+static inline
+void bcm43xx_pio_tx_resume(struct bcm43xx_pioqueue *queue)
+{
+}
 
 #endif /* CONFIG_BCM43XX_PIO */
 #endif /* BCM43xx_PIO_H_ */