diff options
Diffstat (limited to 'drivers/net/wireless/b43')
| -rw-r--r-- | drivers/net/wireless/b43/dma.c | 197 | ||||
| -rw-r--r-- | drivers/net/wireless/b43/dma.h | 7 |
2 files changed, 158 insertions, 46 deletions
diff --git a/drivers/net/wireless/b43/dma.c b/drivers/net/wireless/b43/dma.c index b5cd7f57055..18b97c02b8a 100644 --- a/drivers/net/wireless/b43/dma.c +++ b/drivers/net/wireless/b43/dma.c @@ -383,44 +383,160 @@ static inline } } +/* Check if a DMA region fits the device constraints. + * Returns true, if the region is OK for usage with this device. */ +static inline bool b43_dma_address_ok(struct b43_dmaring *ring, + dma_addr_t addr, size_t size) +{ + switch (ring->type) { + case B43_DMA_30BIT: + if ((u64)addr + size > (1ULL << 30)) + return 0; + break; + case B43_DMA_32BIT: + if ((u64)addr + size > (1ULL << 32)) + return 0; + break; + case B43_DMA_64BIT: + /* Currently we can't have addresses beyond + * 64bit in the kernel. */ + break; + } + return 1; +} + +#define is_4k_aligned(addr) (((u64)(addr) & 0x0FFFull) == 0) +#define is_8k_aligned(addr) (((u64)(addr) & 0x1FFFull) == 0) + +static void b43_unmap_and_free_ringmem(struct b43_dmaring *ring, void *base, + dma_addr_t dmaaddr, size_t size) +{ + ssb_dma_unmap_single(ring->dev->dev, dmaaddr, size, DMA_TO_DEVICE); + free_pages((unsigned long)base, get_order(size)); +} + +static void * __b43_get_and_map_ringmem(struct b43_dmaring *ring, + dma_addr_t *dmaaddr, size_t size, + gfp_t gfp_flags) +{ + void *base; + + base = (void *)__get_free_pages(gfp_flags, get_order(size)); + if (!base) + return NULL; + memset(base, 0, size); + *dmaaddr = ssb_dma_map_single(ring->dev->dev, base, size, + DMA_TO_DEVICE); + if (ssb_dma_mapping_error(ring->dev->dev, *dmaaddr)) { + free_pages((unsigned long)base, get_order(size)); + return NULL; + } + + return base; +} + +static void * b43_get_and_map_ringmem(struct b43_dmaring *ring, + dma_addr_t *dmaaddr, size_t size) +{ + void *base; + + base = __b43_get_and_map_ringmem(ring, dmaaddr, size, + GFP_KERNEL); + if (!base) { + b43err(ring->dev->wl, "Failed to allocate or map pages " + "for DMA ringmemory\n"); + return NULL; + } + if (!b43_dma_address_ok(ring, *dmaaddr, size)) { + /* The memory does not fit our device constraints. + * Retry with GFP_DMA set to get lower memory. */ + b43_unmap_and_free_ringmem(ring, base, *dmaaddr, size); + base = __b43_get_and_map_ringmem(ring, dmaaddr, size, + GFP_KERNEL | GFP_DMA); + if (!base) { + b43err(ring->dev->wl, "Failed to allocate or map pages " + "in the GFP_DMA region for DMA ringmemory\n"); + return NULL; + } + if (!b43_dma_address_ok(ring, *dmaaddr, size)) { + b43_unmap_and_free_ringmem(ring, base, *dmaaddr, size); + b43err(ring->dev->wl, "Failed to allocate DMA " + "ringmemory that fits device constraints\n"); + return NULL; + } + } + /* We expect the memory to be 4k aligned, at least. */ + if (B43_WARN_ON(!is_4k_aligned(*dmaaddr))) { + b43_unmap_and_free_ringmem(ring, base, *dmaaddr, size); + return NULL; + } + + return base; +} + static int alloc_ringmemory(struct b43_dmaring *ring) { - gfp_t flags = GFP_KERNEL; - - /* The specs call for 4K buffers for 30- and 32-bit DMA with 4K - * alignment and 8K buffers for 64-bit DMA with 8K alignment. Testing - * has shown that 4K is sufficient for the latter as long as the buffer - * does not cross an 8K boundary. - * - * For unknown reasons - possibly a hardware error - the BCM4311 rev - * 02, which uses 64-bit DMA, needs the ring buffer in very low memory, - * which accounts for the GFP_DMA flag below. - * - * The flags here must match the flags in free_ringmemory below! + unsigned int required; + void *base; + dma_addr_t dmaaddr; + + /* There are several requirements to the descriptor ring memory: + * - The memory region needs to fit the address constraints for the + * device (same as for frame buffers). + * - For 30/32bit DMA devices, the descriptor ring must be 4k aligned. + * - For 64bit DMA devices, the descriptor ring must be 8k aligned. */ + if (ring->type == B43_DMA_64BIT) - flags |= GFP_DMA; - ring->descbase = ssb_dma_alloc_consistent(ring->dev->dev, - B43_DMA_RINGMEMSIZE, - &(ring->dmabase), flags); - if (!ring->descbase) { - b43err(ring->dev->wl, "DMA ringmemory allocation failed\n"); + required = ring->nr_slots * sizeof(struct b43_dmadesc64); + else + required = ring->nr_slots * sizeof(struct b43_dmadesc32); + if (B43_WARN_ON(required > 0x1000)) + return -ENOMEM; + + ring->alloc_descsize = 0x1000; + base = b43_get_and_map_ringmem(ring, &dmaaddr, ring->alloc_descsize); + if (!base) + return -ENOMEM; + ring->alloc_descbase = base; + ring->alloc_dmabase = dmaaddr; + + if ((ring->type != B43_DMA_64BIT) || is_8k_aligned(dmaaddr)) { + /* We're on <=32bit DMA, or we already got 8k aligned memory. + * That's all we need, so we're fine. */ + ring->descbase = base; + ring->dmabase = dmaaddr; + return 0; + } + b43_unmap_and_free_ringmem(ring, base, dmaaddr, ring->alloc_descsize); + + /* Ok, we failed at the 8k alignment requirement. + * Try to force-align the memory region now. */ + ring->alloc_descsize = 0x2000; + base = b43_get_and_map_ringmem(ring, &dmaaddr, ring->alloc_descsize); + if (!base) return -ENOMEM; + ring->alloc_descbase = base; + ring->alloc_dmabase = dmaaddr; + + if (is_8k_aligned(dmaaddr)) { + /* We're already 8k aligned. That Ok, too. */ + ring->descbase = base; + ring->dmabase = dmaaddr; + return 0; } - memset(ring->descbase, 0, B43_DMA_RINGMEMSIZE); + /* Force-align it to 8k */ + ring->descbase = (void *)((u8 *)base + 0x1000); + ring->dmabase = dmaaddr + 0x1000; + B43_WARN_ON(!is_8k_aligned(ring->dmabase)); return 0; } static void free_ringmemory(struct b43_dmaring *ring) { - gfp_t flags = GFP_KERNEL; - - if (ring->type == B43_DMA_64BIT) - flags |= GFP_DMA; - - ssb_dma_free_consistent(ring->dev->dev, B43_DMA_RINGMEMSIZE, - ring->descbase, ring->dmabase, flags); + b43_unmap_and_free_ringmem(ring, ring->alloc_descbase, + ring->alloc_dmabase, ring->alloc_descsize); } /* Reset the RX DMA channel */ @@ -530,29 +646,14 @@ static bool b43_dma_mapping_error(struct b43_dmaring *ring, if (unlikely(ssb_dma_mapping_error(ring->dev->dev, addr))) return 1; - switch (ring->type) { - case B43_DMA_30BIT: - if ((u64)addr + buffersize > (1ULL << 30)) - goto address_error; - break; - case B43_DMA_32BIT: - if ((u64)addr + buffersize > (1ULL << 32)) - goto address_error; - break; - case B43_DMA_64BIT: - /* Currently we can't have addresses beyond - * 64bit in the kernel. */ - break; + if (!b43_dma_address_ok(ring, addr, buffersize)) { + /* We can't support this address. Unmap it again. */ + unmap_descbuffer(ring, addr, buffersize, dma_to_device); + return 1; } /* The address is OK. */ return 0; - -address_error: - /* We can't support this address. Unmap it again. */ - unmap_descbuffer(ring, addr, buffersize, dma_to_device); - - return 1; } static bool b43_rx_buffer_is_poisoned(struct b43_dmaring *ring, struct sk_buff *skb) @@ -614,6 +715,9 @@ static int setup_rx_descbuffer(struct b43_dmaring *ring, meta->dmaaddr = dmaaddr; ring->ops->fill_descriptor(ring, desc, dmaaddr, ring->rx_buffersize, 0, 0, 0); + ssb_dma_sync_single_for_device(ring->dev->dev, + ring->alloc_dmabase, + ring->alloc_descsize, DMA_TO_DEVICE); return 0; } @@ -1246,6 +1350,9 @@ static int dma_tx_fragment(struct b43_dmaring *ring, } /* Now transfer the whole frame. */ wmb(); + ssb_dma_sync_single_for_device(ring->dev->dev, + ring->alloc_dmabase, + ring->alloc_descsize, DMA_TO_DEVICE); ops->poke_tx(ring, next_slot(ring, slot)); return 0; diff --git a/drivers/net/wireless/b43/dma.h b/drivers/net/wireless/b43/dma.h index f0b0838fb5b..356a0ff8f04 100644 --- a/drivers/net/wireless/b43/dma.h +++ b/drivers/net/wireless/b43/dma.h @@ -157,7 +157,6 @@ struct b43_dmadesc_generic { } __attribute__ ((__packed__)); /* Misc DMA constants */ -#define B43_DMA_RINGMEMSIZE PAGE_SIZE #define B43_DMA0_RX_FRAMEOFFSET 30 /* DMA engine tuning knobs */ @@ -243,6 +242,12 @@ struct b43_dmaring { /* The QOS priority assigned to this ring. Only used for TX rings. * This is the mac80211 "queue" value. */ u8 queue_prio; + /* Pointers and size of the originally allocated and mapped memory + * region for the descriptor ring. */ + void *alloc_descbase; + dma_addr_t alloc_dmabase; + unsigned int alloc_descsize; + /* Pointer to our wireless device. */ struct b43_wldev *dev; #ifdef CONFIG_B43_DEBUG /* Maximum number of used slots. */ |