diff options
| author | Michael Buesch <mb@bu3sch.de> | 2008-04-23 19:13:01 +0200 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2008-04-23 21:25:36 -0400 |
| commit | 1033b3ea11820ea1fb1b877207bd6724e9aaedc3 (patch) | |
| tree | 6037db5b31dcaa0596f5cca9843612707c881279 /drivers | |
| parent | 0da926f05748d273e7b2b673b0de21629ae9acdd (diff) | |
| download | kernel_samsung_smdk4412-1033b3ea11820ea1fb1b877207bd6724e9aaedc3.zip kernel_samsung_smdk4412-1033b3ea11820ea1fb1b877207bd6724e9aaedc3.tar.gz kernel_samsung_smdk4412-1033b3ea11820ea1fb1b877207bd6724e9aaedc3.tar.bz2 | |
b43: Workaround DMA quirks
Some mainboards/CPUs don't allow DMA masks bigger than a certain limit.
Some VIA crap^h^h^h^hdevices have an upper limit of 0xFFFFFFFF. So in this
case a 64-bit b43 device would always fail to acquire the mask.
Implement a workaround to fallback to lower DMA mask, as we can always
also support a lower mask.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/wireless/b43/dma.c | 47 |
1 files changed, 39 insertions, 8 deletions
diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c index 21c886a..6dcbb3c 100644 --- a/drivers/net/wireless/b43/dma.c +++ b/drivers/net/wireless/b43/dma.c @@ -980,6 +980,42 @@ void b43_dma_free(struct b43_wldev *dev) destroy_ring(dma, tx_ring_mcast); } +static int b43_dma_set_mask(struct b43_wldev *dev, u64 mask) +{ + u64 orig_mask = mask; + bool fallback = 0; + int err; + + /* Try to set the DMA mask. If it fails, try falling back to a + * lower mask, as we can always also support a lower one. */ + while (1) { + err = ssb_dma_set_mask(dev->dev, mask); + if (!err) + break; + if (mask == DMA_64BIT_MASK) { + mask = DMA_32BIT_MASK; + fallback = 1; + continue; + } + if (mask == DMA_32BIT_MASK) { + mask = DMA_30BIT_MASK; + fallback = 1; + continue; + } + b43err(dev->wl, "The machine/kernel does not support " + "the required %u-bit DMA mask\n", + (unsigned int)dma_mask_to_engine_type(orig_mask)); + return -EOPNOTSUPP; + } + if (fallback) { + b43info(dev->wl, "DMA mask fallback from %u-bit to %u-bit\n", + (unsigned int)dma_mask_to_engine_type(orig_mask), + (unsigned int)dma_mask_to_engine_type(mask)); + } + + return 0; +} + int b43_dma_init(struct b43_wldev *dev) { struct b43_dma *dma = &dev->dma; @@ -989,14 +1025,9 @@ int b43_dma_init(struct b43_wldev *dev) dmamask = supported_dma_mask(dev); type = dma_mask_to_engine_type(dmamask); - err = ssb_dma_set_mask(dev->dev, dmamask); - if (err) { - b43err(dev->wl, "The machine/kernel does not support " - "the required DMA mask (0x%08X%08X)\n", - (unsigned int)((dmamask & 0xFFFFFFFF00000000ULL) >> 32), - (unsigned int)(dmamask & 0x00000000FFFFFFFFULL)); - return -EOPNOTSUPP; - } + err = b43_dma_set_mask(dev, dmamask); + if (err) + return err; err = -ENOMEM; /* setup TX DMA channels. */ |