[PATCH] bcm43xx: Partially fix PIO code. Add Kconfig option for PIO or DMA mode (or both).

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

drivers/net/wireless/Kconfig

@@ -500,23 +500,7 @@ config PRISM54
 	  will be called prism54.ko.
 
 source "drivers/net/wireless/hostap/Kconfig"
-
-config BCM43XX
-	tristate "Broadcom BCM43xx wireless support"
-	depends on PCI && IEEE80211 && NET_RADIO && IEEE80211_SOFTMAC && EXPERIMENTAL
-	select FW_LOADER
-	---help---
-	  This is an experimental driver for the Broadcom 43xx wireless chip,
-	  found in the Apple Airport Extreme and various other devices.
-
-config BCM43XX_DEBUG
-	bool "Broadcom BCM43xx debugging (RECOMMENDED)"
-	depends on BCM43XX
-	default y
-	---help---
-	  Broadcom 43xx debugging messages.
-	  Say Y, because the driver is still very experimental and
-	  this will help you get it running.
+source "drivers/net/wireless/bcm43xx/Kconfig"
 
 # yes, this works even when no drivers are selected
 config NET_WIRELESS

drivers/net/wireless/bcm43xx/Kconfig

+config BCM43XX
+	tristate "Broadcom BCM43xx wireless support"
+	depends on PCI && IEEE80211 && IEEE80211_SOFTMAC && NET_RADIO && EXPERIMENTAL
+	select FW_LOADER
+	---help---
+	  This is an experimental driver for the Broadcom 43xx wireless chip,
+	  found in the Apple Airport Extreme and various other devices.
+
+config BCM43XX_DEBUG
+	bool "Broadcom BCM43xx debugging (RECOMMENDED)"
+	depends on BCM43XX
+	default y
+	---help---
+	  Broadcom 43xx debugging messages.
+	  Say Y, because the driver is still very experimental and
+	  this will help you get it running.
+
+config BCM43XX_DMA
+	bool
+config BCM43XX_PIO
+	bool
+
+choice
+	prompt "BCM43xx data transfer mode"
+	depends on BCM43XX
+	default BCM43XX_DMA_AND_PIO
+
+config BCM43XX_DMA_AND_PIO_MODE
+	bool "DMA + PIO"
+	select BCM43XX_DMA
+	select BCM43XX_PIO
+	---help---
+	  Include both, Direct Memory Access (DMA) and Programmed I/O (PIO)
+	  data transfer modes.
+	  The actually used mode is selectable through the module
+	  parameter "pio". If the module parameter is pio=0, DMA is used.
+	  Otherwise PIO is used. DMA is default.
+
+	  If unsure, choose this option.
+
+config BCM43XX_DMA_MODE
+	bool "DMA (Direct Memory Access) only"
+	select BCM43XX_DMA
+	---help---
+	  Only include Direct Memory Access (DMA).
+	  This reduces the size of the driver module, by omitting the PIO code.
+
+config BCM43XX_PIO_MODE
+	bool "PIO (Programmed I/O) only"
+	select BCM43XX_PIO
+	---help---
+	  Only include Programmed I/O (PIO).
+	  This reduces the size of the driver module, by omitting the DMA code.
+	  Please note that PIO transfers are slow (compared to DMA).
+	  Only use PIO, if DMA does not work for you.
+
+endchoice

drivers/net/wireless/bcm43xx/Makefile

 obj-$(CONFIG_BCM43XX) += bcm43xx.o
 bcm43xx-obj-$(CONFIG_BCM43XX_DEBUG) += bcm43xx_debugfs.o
 
-bcm43xx-objs := bcm43xx_main.o bcm43xx_dma.o \
+bcm43xx-obj-$(CONFIG_BCM43XX_DMA) += bcm43xx_dma.o
+bcm43xx-obj-$(CONFIG_BCM43XX_PIO) += bcm43xx_pio.o
+
+bcm43xx-objs := bcm43xx_main.o bcm43xx_ilt.o \
 		bcm43xx_radio.o bcm43xx_phy.o \
 		bcm43xx_power.o bcm43xx_wx.o \
-		bcm43xx_pio.o bcm43xx_ilt.o \
 		bcm43xx_leds.o bcm43xx_ethtool.o \
 		$(bcm43xx-obj-y)

drivers/net/wireless/bcm43xx/bcm43xx.h

@@ -639,7 +639,7 @@ struct bcm43xx_private {
 	u32 initialized:1,		/* init_board() succeed */
 	    was_initialized:1,		/* for PCI suspend/resume. */
 	    shutting_down:1,		/* free_board() in progress */
-	    pio_mode:1,			/* PIO (if true), or DMA (if false) used. */
+	    __using_pio:1,		/* Internal, use bcm43xx_using_pio(). */
 	    bad_frames_preempt:1,	/* Use "Bad Frames Preemption" (default off) */
 	    reg124_set_0x4:1,		/* Some variable to keep track of IRQ stuff. */
 	    powersaving:1,		/* TRUE if we are in PowerSaving mode. FALSE otherwise. */
@@ -749,6 +749,33 @@ struct bcm43xx_private * bcm43xx_priv(struct net_device *dev)
 	return ieee80211softmac_priv(dev);
 }
 
+
+/* Helper function, which returns a boolean.
+ * TRUE, if PIO is used; FALSE, if DMA is used.
+ */
+#if defined(CONFIG_BCM43XX_DMA) && defined(CONFIG_BCM43XX_PIO)
+static inline
+int bcm43xx_using_pio(struct bcm43xx_private *bcm)
+{
+	return bcm->__using_pio;
+}
+#elif defined(CONFIG_BCM43XX_DMA)
+static inline
+int bcm43xx_using_pio(struct bcm43xx_private *bcm)
+{
+	return 0;
+}
+#elif defined(CONFIG_BCM43XX_PIO)
+static inline
+int bcm43xx_using_pio(struct bcm43xx_private *bcm)
+{
+	return 1;
+}
+#else
+# error "Using neither DMA nor PIO? Confused..."
+#endif
+
+
 static inline
 int bcm43xx_num_80211_cores(struct bcm43xx_private *bcm)
 {

drivers/net/wireless/bcm43xx/bcm43xx_dma.h

@@ -94,6 +94,10 @@
 #define BCM43xx_TXRESUME_PERCENT	50
 
 
+
+#ifdef CONFIG_BCM43XX_DMA
+
+
 struct sk_buff;
 struct bcm43xx_private;
 struct bcm43xx_xmitstatus;
@@ -172,4 +176,46 @@ int bcm43xx_dma_tx(struct bcm43xx_private *bcm,
 		   struct ieee80211_txb *txb);
 void bcm43xx_dma_rx(struct bcm43xx_dmaring *ring);
 
+
+#else /* CONFIG_BCM43XX_DMA */
+
+
+static inline
+int bcm43xx_dma_init(struct bcm43xx_private *bcm)
+{
+	return 0;
+}
+static inline
+void bcm43xx_dma_free(struct bcm43xx_private *bcm)
+{
+}
+static inline
+int bcm43xx_dmacontroller_rx_reset(struct bcm43xx_private *bcm,
+				   u16 dmacontroller_mmio_base)
+{
+	return 0;
+}
+static inline
+int bcm43xx_dmacontroller_tx_reset(struct bcm43xx_private *bcm,
+				   u16 dmacontroller_mmio_base)
+{
+	return 0;
+}
+static inline
+int bcm43xx_dma_tx(struct bcm43xx_private *bcm,
+		   struct ieee80211_txb *txb)
+{
+	return 0;
+}
+static inline
+void bcm43xx_dma_handle_xmitstatus(struct bcm43xx_private *bcm,
+				   struct bcm43xx_xmitstatus *status)
+{
+}
+static inline
+void bcm43xx_dma_rx(struct bcm43xx_dmaring *ring)
+{
+}
+
+#endif /* CONFIG_BCM43XX_DMA */
 #endif /* BCM43xx_DMA_H_ */

drivers/net/wireless/bcm43xx/bcm43xx_main.c

@@ -62,10 +62,15 @@ MODULE_LICENSE("GPL");
 extern char *nvram_get(char *name);
 #endif
 
-/* Module parameters */
+#if defined(CONFIG_BCM43XX_DMA) && defined(CONFIG_BCM43XX_PIO)
 static int modparam_pio;
 module_param_named(pio, modparam_pio, int, 0444);
 MODULE_PARM_DESC(pio, "enable(1) / disable(0) PIO mode");
+#elif defined(CONFIG_BCM43XX_DMA)
+# define modparam_pio	0
+#elif defined(CONFIG_BCM43XX_PIO)
+# define modparam_pio	1
+#endif
 
 static int modparam_bad_frames_preempt;
 module_param_named(bad_frames_preempt, modparam_bad_frames_preempt, int, 0444);
@@ -1528,7 +1533,8 @@ void bcm43xx_wireless_core_reset(struct bcm43xx_private *bcm, int connect_phy)
 {
 	u32 flags = 0x00040000;
 
-	if ((bcm43xx_core_enabled(bcm)) && (!bcm->pio_mode)) {
+	if ((bcm43xx_core_enabled(bcm)) &&
+	    !bcm43xx_using_pio(bcm)) {
 //FIXME: Do we _really_ want #ifndef CONFIG_BCM947XX here?
 #ifndef CONFIG_BCM947XX
 		/* reset all used DMA controllers. */
@@ -1635,7 +1641,7 @@ static inline void handle_irq_transmit_status(struct bcm43xx_private *bcm)
 		}
 		//TODO: There are more (unknown) flags to test. see bcm43xx_main.h
 
-		if (bcm->pio_mode)
+		if (bcm43xx_using_pio(bcm))
 			bcm43xx_pio_handle_xmitstatus(bcm, &stat);
 		else
 			bcm43xx_dma_handle_xmitstatus(bcm, &stat);
@@ -1933,7 +1939,7 @@ static void bcm43xx_interrupt_tasklet(struct bcm43xx_private *bcm)
 	assert(!(dma_reason[1] & BCM43xx_DMAIRQ_RX_DONE));
 	assert(!(dma_reason[2] & BCM43xx_DMAIRQ_RX_DONE));
 	if (dma_reason[0] & BCM43xx_DMAIRQ_RX_DONE) {
-		if (bcm->pio_mode)
+		if (bcm43xx_using_pio(bcm))
 			bcm43xx_pio_rx(bcm->current_core->pio->queue0);
 		else
 			bcm43xx_dma_rx(bcm->current_core->dma->rx_ring0);
@@ -1941,7 +1947,7 @@ static void bcm43xx_interrupt_tasklet(struct bcm43xx_private *bcm)
 	}
 	if (dma_reason[3] & BCM43xx_DMAIRQ_RX_DONE) {
 		if (likely(bcm->current_core->rev < 5)) {
-			if (bcm->pio_mode)
+			if (bcm43xx_using_pio(bcm))
 				bcm43xx_pio_rx(bcm->current_core->pio->queue3);
 			else
 				bcm43xx_dma_rx(bcm->current_core->dma->rx_ring1);
@@ -1999,7 +2005,7 @@ void bcm43xx_interrupt_ack(struct bcm43xx_private *bcm,
 	bcm->dma_reason[3] = bcm43xx_read32(bcm, BCM43xx_MMIO_DMA4_REASON)
 			     & 0x0001dc00;
 
-	if ((bcm->pio_mode) &&
+	if (bcm43xx_using_pio(bcm) &&
 	    (bcm->current_core->rev < 3) &&
 	    (!(reason & BCM43xx_IRQ_PIO_WORKAROUND))) {
 		/* Apply a PIO specific workaround to the dma_reasons */
@@ -2624,7 +2630,7 @@ static int bcm43xx_chip_init(struct bcm43xx_private *bcm)
 	value32 |= 0x100000; //FIXME: What's this? Is this correct?
 	bcm43xx_write32(bcm, BCM43xx_MMIO_STATUS_BITFIELD, value32);
 
-	if (bcm->pio_mode) {
+	if (bcm43xx_using_pio(bcm)) {
 		bcm43xx_write32(bcm, 0x0210, 0x00000100);
 		bcm43xx_write32(bcm, 0x0230, 0x00000100);
 		bcm43xx_write32(bcm, 0x0250, 0x00000100);
@@ -3123,15 +3129,12 @@ static int bcm43xx_wireless_core_init(struct bcm43xx_private *bcm)
 	if (bcm->current_core->rev >= 5)
 		bcm43xx_write16(bcm, 0x043C, 0x000C);
 
-	if (!bcm->pio_mode) {
-		err = bcm43xx_dma_init(bcm);
-		if (err)
-			goto err_chip_cleanup;
-	} else {
+	if (bcm43xx_using_pio(bcm))
 		err = bcm43xx_pio_init(bcm);
+	else
+		err = bcm43xx_dma_init(bcm);
 	if (err)
 		goto err_chip_cleanup;
-	}
 	bcm43xx_write16(bcm, 0x0612, 0x0050);
 	bcm43xx_shm_write16(bcm, BCM43xx_SHM_SHARED, 0x0416, 0x0050);
 	bcm43xx_shm_write16(bcm, BCM43xx_SHM_SHARED, 0x0414, 0x01F4);
@@ -4001,8 +4004,8 @@ static inline int bcm43xx_tx(struct bcm43xx_private *bcm,
 {
 	int err = -ENODEV;
 
-	if (bcm->pio_mode)
-		err = bcm43xx_pio_transfer_txb(bcm, txb);
+	if (bcm43xx_using_pio(bcm))
+		err = bcm43xx_pio_tx(bcm, txb);
 	else
 		err = bcm43xx_dma_tx(bcm, txb);
 
@@ -4158,7 +4161,7 @@ static int bcm43xx_net_stop(struct net_device *net_dev)
 	return 0;
 }
 
-static void bcm43xx_init_private(struct bcm43xx_private *bcm,
+static int bcm43xx_init_private(struct bcm43xx_private *bcm,
 				struct net_device *net_dev,
 				struct pci_dev *pci_dev,
 				struct workqueue_struct *wq)
@@ -4190,13 +4193,17 @@ static void bcm43xx_init_private(struct bcm43xx_private *bcm,
 		     (unsigned long)bcm);
 	tasklet_disable_nosync(&bcm->isr_tasklet);
 	if (modparam_pio) {
-		bcm->pio_mode = 1;
-	} else {
-		if (pci_set_dma_mask(pci_dev, DMA_30BIT_MASK) == 0) {
-			bcm->pio_mode = 0;
+		bcm->__using_pio = 1;
 	} else {
+		if (pci_set_dma_mask(pci_dev, DMA_30BIT_MASK)) {
+#ifdef CONFIG_BCM43XX_PIO
 			printk(KERN_WARNING PFX "DMA not supported. Falling back to PIO.\n");
-			bcm->pio_mode = 1;
+			bcm->__using_pio = 1;
+#else
+			printk(KERN_ERR PFX "FATAL: DMA not supported and PIO not configured. "
+					    "Recompile the driver with PIO support, please.\n");
+			return -ENODEV;
+#endif /* CONFIG_BCM43XX_PIO */
 		}
 	}
 	bcm->rts_threshold = BCM43xx_DEFAULT_RTS_THRESHOLD;
@@ -4210,6 +4217,8 @@ static void bcm43xx_init_private(struct bcm43xx_private *bcm,
 	bcm->ieee->tx_headroom = sizeof(struct bcm43xx_txhdr);
 	bcm->ieee->set_security = bcm43xx_ieee80211_set_security;
 	bcm->ieee->hard_start_xmit = bcm43xx_ieee80211_hard_start_xmit;
+
+	return 0;
 }
 
 static int __devinit bcm43xx_init_one(struct pci_dev *pdev,
@@ -4261,7 +4270,9 @@ static int __devinit bcm43xx_init_one(struct pci_dev *pdev,
 		err = -ENOMEM;
 		goto err_free_netdev;
 	}
-	bcm43xx_init_private(bcm, net_dev, pdev, wq);
+	err = bcm43xx_init_private(bcm, net_dev, pdev, wq);
+	if (err)
+		goto err_destroy_wq;
 
 	pci_set_drvdata(pdev, net_dev);
 
@@ -4325,7 +4336,9 @@ static void bcm43xx_chip_reset(void *_bcm)
 		bcm43xx_free_board(bcm);
 	bcm->firmware_norelease = 0;
 	bcm43xx_detach_board(bcm);
-	bcm43xx_init_private(bcm, net_dev, pci_dev, wq);
+	err = bcm43xx_init_private(bcm, net_dev, pci_dev, wq);
+	if (err)
+		goto failure;
 	err = bcm43xx_attach_board(bcm);
 	if (err)
 		goto failure;

drivers/net/wireless/bcm43xx/bcm43xx_pio.h

@@ -3,9 +3,8 @@
 
 #include "bcm43xx.h"
 
+#include <linux/interrupt.h>
 #include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/workqueue.h>
 #include <linux/skbuff.h>
 
 
@@ -32,6 +31,10 @@
 #define BCM43xx_PIO_MAXTXPACKETS	256
 
 
+
+#ifdef CONFIG_BCM43XX_PIO
+
+
 struct bcm43xx_pioqueue;
 struct bcm43xx_xmitstatus;
 
@@ -44,13 +47,14 @@ struct bcm43xx_pio_txpacket {
 	u16 xmitted_octets;
 };
 
-#define pio_txpacket_getindex(packet) ((int)((packet) - (packet)->queue->__tx_packets_cache)) 
+#define pio_txpacket_getindex(packet) ((int)((packet) - (packet)->queue->tx_packets_cache)) 
 
 struct bcm43xx_pioqueue {
 	struct bcm43xx_private *bcm;
 	u16 mmio_base;
 
-	u8 tx_suspended:1;
+	u8 tx_suspended:1,
+	   need_workarounds:1; /* Workarounds needed for core.rev < 3 */
 
 	/* Adjusted size of the device internal TX buffer. */
 	u16 tx_devq_size;
@@ -62,6 +66,7 @@ struct bcm43xx_pioqueue {
 	 * be taken on incoming TX requests.
 	 */
 	struct list_head txfree;
+	unsigned int nr_txfree;
 	/* Packets on the txqueue are queued,
 	 * but not completely written to the chip, yet.
 	 */
@@ -70,19 +75,64 @@ struct bcm43xx_pioqueue {
 	 * posted to the device. We are waiting for the txstatus.
 	 */
 	struct list_head txrunning;
-	/* Locking of the TX queues and the accounting. */
-	spinlock_t txlock;
-	struct work_struct txwork;
-	struct bcm43xx_pio_txpacket __tx_packets_cache[BCM43xx_PIO_MAXTXPACKETS];
+	/* Total number or packets sent.
+	 * (This counter can obviously wrap).
+	 */
+	unsigned int nr_tx_packets;
+	struct tasklet_struct txtask;
+	struct bcm43xx_pio_txpacket tx_packets_cache[BCM43xx_PIO_MAXTXPACKETS];
 };
 
+static inline
+u16 bcm43xx_pio_read(struct bcm43xx_pioqueue *queue,
+		     u16 offset)
+{
+	return bcm43xx_read16(queue->bcm, queue->mmio_base + offset);
+}
+
+static inline
+void bcm43xx_pio_write(struct bcm43xx_pioqueue *queue,
+		       u16 offset, u16 value)
+{
+	bcm43xx_write16(queue->bcm, queue->mmio_base + offset, value);
+}
+
+
 int bcm43xx_pio_init(struct bcm43xx_private *bcm);
 void bcm43xx_pio_free(struct bcm43xx_private *bcm);
 
-int FASTCALL(bcm43xx_pio_transfer_txb(struct bcm43xx_private *bcm,
-				      struct ieee80211_txb *txb));
-void FASTCALL(bcm43xx_pio_handle_xmitstatus(struct bcm43xx_private *bcm,
-					    struct bcm43xx_xmitstatus *status));
-
-void FASTCALL(bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue));
+int bcm43xx_pio_tx(struct bcm43xx_private *bcm,
+		   struct ieee80211_txb *txb);
+void bcm43xx_pio_handle_xmitstatus(struct bcm43xx_private *bcm,
+				   struct bcm43xx_xmitstatus *status);
+void bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue);
+
+#else /* CONFIG_BCM43XX_PIO */
+
+static inline
+int bcm43xx_pio_init(struct bcm43xx_private *bcm)
+{
+	return 0;
+}
+static inline
+void bcm43xx_pio_free(struct bcm43xx_private *bcm)
+{
+}
+static inline
+int bcm43xx_pio_tx(struct bcm43xx_private *bcm,
+		   struct ieee80211_txb *txb)
+{
+	return 0;
+}
+static inline
+void bcm43xx_pio_handle_xmitstatus(struct bcm43xx_private *bcm,
+				   struct bcm43xx_xmitstatus *status)
+{
+}
+static inline
+void bcm43xx_pio_rx(struct bcm43xx_pioqueue *queue)
+{
+}
+
+#endif /* CONFIG_BCM43XX_PIO */
 #endif /* BCM43xx_PIO_H_ */