[patch 14/20] bcm43xx: Fix problem with >1 GB RAM

From: Greg KH
Date: Sat Mar 10 2007 - 01:21:59 EST


-stable review patch. If anyone has any objections, please let us know.

------------------
From: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

[PATCH] bcm43xx: Fix problem with >1 GB RAM

Some versions of the bcm43xx chips only support 30-bit DMA, which means
that the descriptors and buffers must be in the first 1 GB of RAM. On
the i386 and x86_64 architectures with more than 1 GB RAM, an incorrect
assignment may occur. This patch ensures that the various DMA addresses
are within the capability of the chip. Testing has been limited to x86_64
as no one has an i386 system with more than 1 GB RAM.

Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Signed-off-by: John W. Linville <linville@xxxxxxxxxxxxx>
Cc: Chuck Ebbert <cebbert@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/net/wireless/bcm43xx/bcm43xx.h | 1
drivers/net/wireless/bcm43xx/bcm43xx_dma.c | 171 +++++++++++++++++++++--------
2 files changed, 125 insertions(+), 47 deletions(-)

--- a/drivers/net/wireless/bcm43xx/bcm43xx.h
+++ b/drivers/net/wireless/bcm43xx/bcm43xx.h
@@ -766,6 +766,7 @@ struct bcm43xx_private {
* This is currently always BCM43xx_BUSTYPE_PCI
*/
u8 bustype;
+ u64 dma_mask;

u16 board_vendor;
u16 board_type;
--- a/drivers/net/wireless/bcm43xx/bcm43xx_dma.c
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_dma.c
@@ -145,16 +145,14 @@ dma_addr_t map_descbuffer(struct bcm43xx
int tx)
{
dma_addr_t dmaaddr;
+ int direction = PCI_DMA_FROMDEVICE;

- if (tx) {
- dmaaddr = dma_map_single(&ring->bcm->pci_dev->dev,
- buf, len,
- DMA_TO_DEVICE);
- } else {
- dmaaddr = dma_map_single(&ring->bcm->pci_dev->dev,
+ if (tx)
+ direction = PCI_DMA_TODEVICE;
+
+ dmaaddr = pci_map_single(ring->bcm->pci_dev,
buf, len,
- DMA_FROM_DEVICE);
- }
+ direction);

return dmaaddr;
}
@@ -166,13 +164,13 @@ void unmap_descbuffer(struct bcm43xx_dma
int tx)
{
if (tx) {
- dma_unmap_single(&ring->bcm->pci_dev->dev,
+ pci_unmap_single(ring->bcm->pci_dev,
addr, len,
- DMA_TO_DEVICE);
+ PCI_DMA_TODEVICE);
} else {
- dma_unmap_single(&ring->bcm->pci_dev->dev,
+ pci_unmap_single(ring->bcm->pci_dev,
addr, len,
- DMA_FROM_DEVICE);
+ PCI_DMA_FROMDEVICE);
}
}

@@ -183,8 +181,8 @@ void sync_descbuffer_for_cpu(struct bcm4
{
assert(!ring->tx);

- dma_sync_single_for_cpu(&ring->bcm->pci_dev->dev,
- addr, len, DMA_FROM_DEVICE);
+ pci_dma_sync_single_for_cpu(ring->bcm->pci_dev,
+ addr, len, PCI_DMA_FROMDEVICE);
}

static inline
@@ -194,8 +192,8 @@ void sync_descbuffer_for_device(struct b
{
assert(!ring->tx);

- dma_sync_single_for_device(&ring->bcm->pci_dev->dev,
- addr, len, DMA_FROM_DEVICE);
+ pci_dma_sync_single_for_cpu(ring->bcm->pci_dev,
+ addr, len, PCI_DMA_TODEVICE);
}

/* Unmap and free a descriptor buffer. */
@@ -214,17 +212,53 @@ void free_descriptor_buffer(struct bcm43

static int alloc_ringmemory(struct bcm43xx_dmaring *ring)
{
- struct device *dev = &(ring->bcm->pci_dev->dev);
-
- ring->descbase = dma_alloc_coherent(dev, BCM43xx_DMA_RINGMEMSIZE,
- &(ring->dmabase), GFP_KERNEL);
+ ring->descbase = pci_alloc_consistent(ring->bcm->pci_dev, BCM43xx_DMA_RINGMEMSIZE,
+ &(ring->dmabase));
if (!ring->descbase) {
- printk(KERN_ERR PFX "DMA ringmemory allocation failed\n");
- return -ENOMEM;
+ /* Allocation may have failed due to pci_alloc_consistent
+ insisting on use of GFP_DMA, which is more restrictive
+ than necessary... */
+ struct dma_desc *rx_ring;
+ dma_addr_t rx_ring_dma;
+
+ rx_ring = kzalloc(BCM43xx_DMA_RINGMEMSIZE, GFP_KERNEL);
+ if (!rx_ring)
+ goto out_err;
+
+ rx_ring_dma = pci_map_single(ring->bcm->pci_dev, rx_ring,
+ BCM43xx_DMA_RINGMEMSIZE,
+ PCI_DMA_BIDIRECTIONAL);
+
+ if (pci_dma_mapping_error(rx_ring_dma) ||
+ rx_ring_dma + BCM43xx_DMA_RINGMEMSIZE > ring->bcm->dma_mask) {
+ /* Sigh... */
+ if (!pci_dma_mapping_error(rx_ring_dma))
+ pci_unmap_single(ring->bcm->pci_dev,
+ rx_ring_dma, BCM43xx_DMA_RINGMEMSIZE,
+ PCI_DMA_BIDIRECTIONAL);
+ rx_ring_dma = pci_map_single(ring->bcm->pci_dev,
+ rx_ring, BCM43xx_DMA_RINGMEMSIZE,
+ PCI_DMA_BIDIRECTIONAL);
+ if (pci_dma_mapping_error(rx_ring_dma) ||
+ rx_ring_dma + BCM43xx_DMA_RINGMEMSIZE > ring->bcm->dma_mask) {
+ assert(0);
+ if (!pci_dma_mapping_error(rx_ring_dma))
+ pci_unmap_single(ring->bcm->pci_dev,
+ rx_ring_dma, BCM43xx_DMA_RINGMEMSIZE,
+ PCI_DMA_BIDIRECTIONAL);
+ goto out_err;
+ }
+ }
+
+ ring->descbase = rx_ring;
+ ring->dmabase = rx_ring_dma;
}
memset(ring->descbase, 0, BCM43xx_DMA_RINGMEMSIZE);

return 0;
+out_err:
+ printk(KERN_ERR PFX "DMA ringmemory allocation failed\n");
+ return -ENOMEM;
}

static void free_ringmemory(struct bcm43xx_dmaring *ring)
@@ -407,6 +441,29 @@ static int setup_rx_descbuffer(struct bc
if (unlikely(!skb))
return -ENOMEM;
dmaaddr = map_descbuffer(ring, skb->data, ring->rx_buffersize, 0);
+ /* This hardware bug work-around adapted from the b44 driver.
+ The chip may be unable to do PCI DMA to/from anything above 1GB */
+ if (pci_dma_mapping_error(dmaaddr) ||
+ dmaaddr + ring->rx_buffersize > ring->bcm->dma_mask) {
+ /* This one has 30-bit addressing... */
+ if (!pci_dma_mapping_error(dmaaddr))
+ pci_unmap_single(ring->bcm->pci_dev,
+ dmaaddr, ring->rx_buffersize,
+ PCI_DMA_FROMDEVICE);
+ dev_kfree_skb_any(skb);
+ skb = __dev_alloc_skb(ring->rx_buffersize,GFP_DMA);
+ if (skb == NULL)
+ return -ENOMEM;
+ dmaaddr = pci_map_single(ring->bcm->pci_dev,
+ skb->data, ring->rx_buffersize,
+ PCI_DMA_FROMDEVICE);
+ if (pci_dma_mapping_error(dmaaddr) ||
+ dmaaddr + ring->rx_buffersize > ring->bcm->dma_mask) {
+ assert(0);
+ dev_kfree_skb_any(skb);
+ return -ENOMEM;
+ }
+ }
meta->skb = skb;
meta->dmaaddr = dmaaddr;
skb->dev = ring->bcm->net_dev;
@@ -636,8 +693,10 @@ struct bcm43xx_dmaring * bcm43xx_setup_d
err = dmacontroller_setup(ring);
if (err)
goto err_free_ringmemory;
+ return ring;

out:
+ printk(KERN_ERR PFX "Error in bcm43xx_setup_dmaring\n");
return ring;

err_free_ringmemory:
@@ -705,30 +764,16 @@ int bcm43xx_dma_init(struct bcm43xx_priv
struct bcm43xx_dmaring *ring;
int err = -ENOMEM;
int dma64 = 0;
- u64 mask = bcm43xx_get_supported_dma_mask(bcm);
- int nobits;

- if (mask == DMA_64BIT_MASK) {
+ bcm->dma_mask = bcm43xx_get_supported_dma_mask(bcm);
+ if (bcm->dma_mask == DMA_64BIT_MASK)
dma64 = 1;
- nobits = 64;
- } else if (mask == DMA_32BIT_MASK)
- nobits = 32;
- else
- nobits = 30;
- err = pci_set_dma_mask(bcm->pci_dev, mask);
- err |= pci_set_consistent_dma_mask(bcm->pci_dev, mask);
- if (err) {
-#ifdef CONFIG_BCM43XX_PIO
- printk(KERN_WARNING PFX "DMA not supported on this device."
- " Falling back to PIO.\n");
- bcm->__using_pio = 1;
- return -ENOSYS;
-#else
- printk(KERN_ERR PFX "FATAL: DMA not supported and PIO not configured. "
- "Please recompile the driver with PIO support.\n");
- return -ENODEV;
-#endif /* CONFIG_BCM43XX_PIO */
- }
+ err = pci_set_dma_mask(bcm->pci_dev, bcm->dma_mask);
+ if (err)
+ goto no_dma;
+ err = pci_set_consistent_dma_mask(bcm->pci_dev, bcm->dma_mask);
+ if (err)
+ goto no_dma;

/* setup TX DMA channels. */
ring = bcm43xx_setup_dmaring(bcm, 0, 1, dma64);
@@ -774,7 +819,9 @@ int bcm43xx_dma_init(struct bcm43xx_priv
dma->rx_ring3 = ring;
}

- dprintk(KERN_INFO PFX "%d-bit DMA initialized\n", nobits);
+ dprintk(KERN_INFO PFX "%d-bit DMA initialized\n",
+ (bcm->dma_mask == DMA_64BIT_MASK) ? 64 :
+ (bcm->dma_mask == DMA_32BIT_MASK) ? 32 : 30);
err = 0;
out:
return err;
@@ -800,7 +847,17 @@ err_destroy_tx1:
err_destroy_tx0:
bcm43xx_destroy_dmaring(dma->tx_ring0);
dma->tx_ring0 = NULL;
- goto out;
+no_dma:
+#ifdef CONFIG_BCM43XX_PIO
+ printk(KERN_WARNING PFX "DMA not supported on this device."
+ " Falling back to PIO.\n");
+ bcm->__using_pio = 1;
+ return -ENOSYS;
+#else
+ printk(KERN_ERR PFX "FATAL: DMA not supported and PIO not configured. "
+ "Please recompile the driver with PIO support.\n");
+ return -ENODEV;
+#endif /* CONFIG_BCM43XX_PIO */
}

/* Generate a cookie for the TX header. */
@@ -905,6 +962,7 @@ static void dma_tx_fragment(struct bcm43
struct bcm43xx_dmadesc_generic *desc;
struct bcm43xx_dmadesc_meta *meta;
dma_addr_t dmaaddr;
+ struct sk_buff *bounce_skb;

assert(skb_shinfo(skb)->nr_frags == 0);

@@ -924,9 +982,28 @@ static void dma_tx_fragment(struct bcm43
skb->len - sizeof(struct bcm43xx_txhdr),
(cur_frag == 0),
generate_cookie(ring, slot));
+ dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
+ if (dma_mapping_error(dmaaddr) || dmaaddr + skb->len > ring->bcm->dma_mask) {
+ /* chip cannot handle DMA to/from > 1GB, use bounce buffer (copied from b44 driver) */
+ if (!dma_mapping_error(dmaaddr))
+ unmap_descbuffer(ring, dmaaddr, skb->len, 1);
+ bounce_skb = __dev_alloc_skb(skb->len, GFP_ATOMIC|GFP_DMA);
+ if (!bounce_skb)
+ return;
+ dmaaddr = map_descbuffer(ring, bounce_skb->data, bounce_skb->len, 1);
+ if (dma_mapping_error(dmaaddr) || dmaaddr + skb->len > ring->bcm->dma_mask) {
+ if (!dma_mapping_error(dmaaddr))
+ unmap_descbuffer(ring, dmaaddr, skb->len, 1);
+ dev_kfree_skb_any(bounce_skb);
+ assert(0);
+ return;
+ }
+ memcpy(skb_put(bounce_skb, skb->len), skb->data, skb->len);
+ dev_kfree_skb_any(skb);
+ skb = bounce_skb;
+ }

meta->skb = skb;
- dmaaddr = map_descbuffer(ring, skb->data, skb->len, 1);
meta->dmaaddr = dmaaddr;

fill_descriptor(ring, desc, dmaaddr,

--
-
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