drivers/net/wireless/broadcom/b43/dma.c

Source file repositories/reference/linux-study-clean/drivers/net/wireless/broadcom/b43/dma.c

File Facts

System
Linux kernel
Corpus path
drivers/net/wireless/broadcom/b43/dma.c
Extension
.c
Size
46924 bytes
Lines
1769
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (dma->translation_in_low) {
			addr &= ~SSB_DMA_TRANSLATION_MASK;
			addr |= dma->translation;
		}
		break;
	case B43_DMA_ADDR_HIGH:
		addr = upper_32_bits(dmaaddr);
		if (!dma->translation_in_low) {
			addr &= ~SSB_DMA_TRANSLATION_MASK;
			addr |= dma->translation;
		}
		break;
	case B43_DMA_ADDR_EXT:
		if (dma->translation_in_low)
			addr = lower_32_bits(dmaaddr);
		else
			addr = upper_32_bits(dmaaddr);
		addr &= SSB_DMA_TRANSLATION_MASK;
		addr >>= SSB_DMA_TRANSLATION_SHIFT;
		break;
	}

	return addr;
}

/* 32bit DMA ops. */
static
struct b43_dmadesc_generic *op32_idx2desc(struct b43_dmaring *ring,
					  int slot,
					  struct b43_dmadesc_meta **meta)
{
	struct b43_dmadesc32 *desc;

	*meta = &(ring->meta[slot]);
	desc = ring->descbase;
	desc = &(desc[slot]);

	return (struct b43_dmadesc_generic *)desc;
}

static void op32_fill_descriptor(struct b43_dmaring *ring,
				 struct b43_dmadesc_generic *desc,
				 dma_addr_t dmaaddr, u16 bufsize,
				 int start, int end, int irq)
{
	struct b43_dmadesc32 *descbase = ring->descbase;
	int slot;
	u32 ctl;
	u32 addr;
	u32 addrext;

	slot = (int)(&(desc->dma32) - descbase);
	B43_WARN_ON(!(slot >= 0 && slot < ring->nr_slots));

	addr = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_LOW);
	addrext = b43_dma_address(&ring->dev->dma, dmaaddr, B43_DMA_ADDR_EXT);

	ctl = bufsize & B43_DMA32_DCTL_BYTECNT;
	if (slot == ring->nr_slots - 1)
		ctl |= B43_DMA32_DCTL_DTABLEEND;
	if (start)
		ctl |= B43_DMA32_DCTL_FRAMESTART;
	if (end)
		ctl |= B43_DMA32_DCTL_FRAMEEND;
	if (irq)
		ctl |= B43_DMA32_DCTL_IRQ;
	ctl |= (addrext << B43_DMA32_DCTL_ADDREXT_SHIFT)
	    & B43_DMA32_DCTL_ADDREXT_MASK;

	desc->dma32.control = cpu_to_le32(ctl);
	desc->dma32.address = cpu_to_le32(addr);
}

static void op32_poke_tx(struct b43_dmaring *ring, int slot)
{
	b43_dma_write(ring, B43_DMA32_TXINDEX,
		      (u32) (slot * sizeof(struct b43_dmadesc32)));
}

static void op32_tx_suspend(struct b43_dmaring *ring)
{
	b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
		      | B43_DMA32_TXSUSPEND);
}

static void op32_tx_resume(struct b43_dmaring *ring)
{
	b43_dma_write(ring, B43_DMA32_TXCTL, b43_dma_read(ring, B43_DMA32_TXCTL)
		      & ~B43_DMA32_TXSUSPEND);
}

Annotation

Implementation Notes