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b43: Fix DMA buffer size handling
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This fixes hidden bugs in the size handling of the DMA buffers.
This sets the RX buffer size to the theoretical max packet size and
fixes passing of the size values to the device (must not subtract the header offset).

These bugs are hidden and don't actually trigger due to the magic +100
offset for the buffer size.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
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Michael Buesch authored and John W. Linville committed Feb 27, 2009
1 parent ca2d559 commit 8eccb53
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Showing 2 changed files with 7 additions and 15 deletions.
9 changes: 2 additions & 7 deletions drivers/net/wireless/b43/dma.c
Original file line number Diff line number Diff line change
Expand Up @@ -74,8 +74,7 @@ static void op32_fill_descriptor(struct b43_dmaring *ring,
addrext = (u32) (dmaaddr & SSB_DMA_TRANSLATION_MASK)
>> SSB_DMA_TRANSLATION_SHIFT;
addr |= ssb_dma_translation(ring->dev->dev);
ctl = (bufsize - ring->frameoffset)
& B43_DMA32_DCTL_BYTECNT;
ctl = bufsize & B43_DMA32_DCTL_BYTECNT;
if (slot == ring->nr_slots - 1)
ctl |= B43_DMA32_DCTL_DTABLEEND;
if (start)
Expand Down Expand Up @@ -177,8 +176,7 @@ static void op64_fill_descriptor(struct b43_dmaring *ring,
ctl0 |= B43_DMA64_DCTL0_FRAMEEND;
if (irq)
ctl0 |= B43_DMA64_DCTL0_IRQ;
ctl1 |= (bufsize - ring->frameoffset)
& B43_DMA64_DCTL1_BYTECNT;
ctl1 |= bufsize & B43_DMA64_DCTL1_BYTECNT;
ctl1 |= (addrext << B43_DMA64_DCTL1_ADDREXT_SHIFT)
& B43_DMA64_DCTL1_ADDREXT_MASK;

Expand Down Expand Up @@ -830,9 +828,6 @@ struct b43_dmaring *b43_setup_dmaring(struct b43_wldev *dev,
if (ring->index == 0) {
ring->rx_buffersize = B43_DMA0_RX_BUFFERSIZE;
ring->frameoffset = B43_DMA0_RX_FRAMEOFFSET;
} else if (ring->index == 3) {
ring->rx_buffersize = B43_DMA3_RX_BUFFERSIZE;
ring->frameoffset = B43_DMA3_RX_FRAMEOFFSET;
} else
B43_WARN_ON(1);
}
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13 changes: 5 additions & 8 deletions drivers/net/wireless/b43/dma.h
Original file line number Diff line number Diff line change
@@ -1,14 +1,12 @@
#ifndef B43_DMA_H_
#define B43_DMA_H_

#include <linux/list.h>
#include <linux/ieee80211.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/linkage.h>
#include <asm/atomic.h>

#include "b43.h"


/* DMA-Interrupt reasons. */
#define B43_DMAIRQ_FATALMASK ((1 << 10) | (1 << 11) | (1 << 12) \
| (1 << 14) | (1 << 15))
Expand Down Expand Up @@ -161,14 +159,13 @@ struct b43_dmadesc_generic {

/* Misc DMA constants */
#define B43_DMA_RINGMEMSIZE PAGE_SIZE
#define B43_DMA0_RX_FRAMEOFFSET 30
#define B43_DMA3_RX_FRAMEOFFSET 0
#define B43_DMA0_RX_FRAMEOFFSET 30

/* DMA engine tuning knobs */
#define B43_TXRING_SLOTS 128
#define B43_RXRING_SLOTS 64
#define B43_DMA0_RX_BUFFERSIZE (2304 + 100)
#define B43_DMA3_RX_BUFFERSIZE 16
#define B43_DMA0_RX_BUFFERSIZE IEEE80211_MAX_FRAME_LEN


struct sk_buff;
struct b43_private;
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