If a user encounters the "Fatal DMA Problem" with a BCM43XX device, and
still wishes to use b43 as the driver, their only option is to rebuild
the kernel with CONFIG_B43_FORCE_PIO. This patch removes this option and
allows PIO mode to be selected with a load-time option for the module.
Once the DMA problem with the BCM4312 devices is solved, this patch will
likely be reverted.
Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
---
Index: wireless-testing/drivers/net/wireless/b43/Kconfig
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43/Kconfig
+++ wireless-testing/drivers/net/wireless/b43/Kconfig
@@ -79,10 +79,11 @@ config B43_SDIO
If unsure, say N.
# Data transfers to the device via PIO
-# This is only needed on PCMCIA and SDIO devices. All others can do DMA properly.
+# Technically, this is only needed on PCMCIA and SDIO devices; but some LP PHYs
+# cannot do DMA properly.
config B43_PIO
bool
- depends on B43 && (B43_SDIO || B43_PCMCIA || B43_FORCE_PIO)
+ depends on B43
select SSB_BLOCKIO
default y
@@ -137,12 +138,4 @@ config B43_DEBUG
for production use.
Only say Y, if you are debugging a problem in the b43 driver sourcecode.
-config B43_FORCE_PIO
- bool "Force usage of PIO instead of DMA"
- depends on B43 && B43_DEBUG
- ---help---
- This will disable DMA and always enable PIO instead.
- Say N!
- This is only for debugging the PIO engine code. You do
- _NOT_ want to enable this.
Index: wireless-testing/drivers/net/wireless/b43/Makefile
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43/Makefile
+++ wireless-testing/drivers/net/wireless/b43/Makefile
@@ -12,7 +12,7 @@ b43-y += xmit.o
b43-y += lo.o
b43-y += wa.o
b43-y += dma.o
-b43-$(CONFIG_B43_PIO) += pio.o
+b43-y += pio.o
b43-y += rfkill.o
b43-$(CONFIG_B43_LEDS) += leds.o
b43-$(CONFIG_B43_PCMCIA) += pcmcia.o
Index: wireless-testing/drivers/net/wireless/b43/b43.h
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43/b43.h
+++ wireless-testing/drivers/net/wireless/b43/b43.h
@@ -821,11 +821,9 @@ struct b43_wl {
/* The device LEDs. */
struct b43_leds leds;
-#ifdef CONFIG_B43_PIO
/* Kmalloc'ed scratch space for PIO TX/RX. Protected by wl->mutex. */
u8 pio_scratchspace[110] __attribute__((__aligned__(8)));
u8 pio_tailspace[4] __attribute__((__aligned__(8)));
-#endif /* CONFIG_B43_PIO */
};
static inline struct b43_wl *hw_to_b43_wl(struct ieee80211_hw *hw)
@@ -876,20 +874,9 @@ static inline void b43_write32(struct b4
static inline bool b43_using_pio_transfers(struct b43_wldev *dev)
{
-#ifdef CONFIG_B43_PIO
return dev->__using_pio_transfers;
-#else
- return 0;
-#endif
}
-#ifdef CONFIG_B43_FORCE_PIO
-# define B43_FORCE_PIO 1
-#else
-# define B43_FORCE_PIO 0
-#endif
-
-
/* Message printing */
void b43info(struct b43_wl *wl, const char *fmt, ...)
__attribute__ ((format(printf, 2, 3)));
Index: wireless-testing/drivers/net/wireless/b43/main.c
===================================================================
--- wireless-testing.orig/drivers/net/wireless/b43/main.c
+++ wireless-testing/drivers/net/wireless/b43/main.c
@@ -102,6 +102,9 @@ int b43_modparam_verbose = B43_VERBOSITY
module_param_named(verbose, b43_modparam_verbose, int, 0644);
MODULE_PARM_DESC(verbose, "Log message verbosity: 0=error, 1=warn, 2=info(default), 3=debug");
+static int modparam_pio;
+module_param_named(pio, modparam_pio, int, 0444);
+MODULE_PARM_DESC(pio, "enable(1) / disable(0) PIO mode");
static const struct ssb_device_id b43_ssb_tbl[] = {
SSB_DEVICE(SSB_VENDOR_BROADCOM, SSB_DEV_80211, 5),
@@ -1786,8 +1789,8 @@ static void b43_do_interrupt_thread(stru
dma_reason[4], dma_reason[5]);
b43err(dev->wl, "This device does not support DMA "
"on your system. Please use PIO instead.\n");
- b43err(dev->wl, "CONFIG_B43_FORCE_PIO must be set in "
- "your kernel configuration.\n");
+ b43err(dev->wl, "Unload the b43 module and reload "
+ "with 'pio=1'\n");
return;
}
if (merged_dma_reason & B43_DMAIRQ_NONFATALMASK) {
@@ -4353,11 +4356,9 @@ static int b43_wireless_core_init(struct
if ((dev->dev->bus->bustype == SSB_BUSTYPE_PCMCIA) ||
(dev->dev->bus->bustype == SSB_BUSTYPE_SDIO) ||
- B43_FORCE_PIO) {
- dev->__using_pio_transfers = 1;
+ dev->__using_pio_transfers) {
err = b43_pio_init(dev);
} else {
- dev->__using_pio_transfers = 0;
err = b43_dma_init(dev);
}
if (err)
@@ -4827,6 +4828,8 @@ static int b43_one_core_attach(struct ss
wldev->wl = wl;
b43_set_status(wldev, B43_STAT_UNINIT);
wldev->bad_frames_preempt = modparam_bad_frames_preempt;
+ if (modparam_pio)
+ wldev->__using_pio_transfers = 1;
INIT_LIST_HEAD(&wldev->list);
err = b43_wireless_core_attach(wldev);
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
