/**
* md_mic_dma_free_chan - Frees up a DMA channel
* @chan: The DMA channel handle
*/
void md_mic_dma_free_chan(struct mic_dma_device *dma_dev,
struct md_mic_dma_chan *chan)
{
CHECK_CHAN(chan);
atomic_set(&(chan->in_use), CHAN_AVAILABLE);
md_mic_dma_enable_chan(dma_dev, chan->ch_num, false);
}
/**
* md_mic_dma_chan_set_desc_ring - Configures the DMA channel desc ring
* @chan: The DMA channel handle
* @desc_ring_phys_addr: Physical address of the desc ring base. Needs to be
* physically contiguous and wired down memory.
* @num_desc: Number of descriptors must be a multiple of cache line size.
* Descriptor size should be determined using sizeof(union md_mic_dma_desc).
* The maximum number of descriptors is defined by
* MIC_MAX_NUM_DESC_PER_RING.
*/
void md_mic_dma_chan_set_desc_ring(struct mic_dma_device *dma_dev,
struct md_mic_dma_chan *chan,
phys_addr_t desc_ring_phys_addr,
uint32_t num_desc)
{
uint32_t chan_num;
uint32_t drar_lo = 0;
uint32_t drar_hi = 0;
CHECK_CHAN(chan);
chan_num = chan->ch_num;
/*
* TODO: Maybe the 2nd condition should be different considering the
* size of union md_mic_dma_desc?
*/
KASSERT((((num_desc) <= MIC_MAX_NUM_DESC_PER_RING) &&
(ALIGN((num_desc - (L1_CACHE_BYTES - 1)), L1_CACHE_BYTES) == num_desc)),
"num_desc > max or not multiple of cache line num 0x%x", num_desc);
md_mic_dma_enable_chan(dma_dev, chan_num, false);
drar_hi = size_to_drar_hi_size(num_desc);
if (MIC_DMA_CHAN_HOST_OWNED == chan->owner) {
drar_hi |= SBOX_DRARHI_SYS_MASK;
drar_hi |= addr_to_drar_hi_smpt_bits(desc_ring_phys_addr);
}
drar_lo = (uint32_t)desc_ring_phys_addr;
drar_hi |= physaddr_to_drarhi_ba(desc_ring_phys_addr);
md_mic_dma_write_mmio(dma_dev, chan_num, REG_DRAR_LO, drar_lo);
md_mic_dma_write_mmio(dma_dev, chan_num, REG_DRAR_HI, drar_hi);
chan->num_desc_in_ring = num_desc;
pr_debug("md_mic_dma_chan_set_desc_ring addr=0x%llx num=%d drar_hi.bits.pageno 0x%x\n",
desc_ring_phys_addr, num_desc,
(uint32_t)(desc_ring_phys_addr >> MIC_SYSTEM_PAGE_SHIFT));
chan->cached_tail = md_mic_dma_chan_read_tail(dma_dev, chan);
md_mic_dma_enable_chan(dma_dev, chan_num, true);
}
int
mic_dma_lib_init(uint8_t *mmio_va_base, struct mic_dma_ctx_t *dma_ctx)
{
int i;
#ifdef _MIC_SCIF_
int ret_value;
#endif
struct dma_channel *ch;
enum md_mic_dma_chan_owner owner, currentOwner;
//pr_debug(PR_PREFIX "Initialized the dma mmio va=%p\n", mmio_va_base);
// Using this to check where the DMA lib is at for now.
currentOwner = mmio_va_base == 0 ? MIC_DMA_CHAN_MIC_OWNED : MIC_DMA_CHAN_HOST_OWNED;
// TODO: multi-card support
md_mic_dma_init(&dma_ctx->dma_dev, mmio_va_base);
for (i = 0 ; i < MAX_NUM_DMA_CHAN; i++) {
ch = &dma_ctx->dma_channels[i];
/* Initialize pointer to parent */
ch->dma_ctx = dma_ctx;
owner = i > __LAST_HOST_CHAN_NUM ? MIC_DMA_CHAN_MIC_OWNED
: MIC_DMA_CHAN_HOST_OWNED;
// This has to be done from card side
ch->chan = md_mic_dma_request_chan(&dma_ctx->dma_dev, owner);
KASSERT((ch->chan != NULL), "dummy\n");
ch->ch_num = ch->chan->ch_num;
#ifdef _MIC_SCIF_
/*
* Host driver would have executed by now and thus setup the
* desc. ring
*/
if (ch->chan->owner == MIC_DMA_CHAN_HOST_OWNED)
md_mic_dma_enable_chan(&dma_ctx->dma_dev, i, true);
#endif
atomic_set(&(ch->flags), CHAN_INUSE); // Mark as used by default
if (currentOwner == owner) {
alloc_dma_desc_ring_mem(ch, dma_ctx);
#ifdef _MIC_SCIF_ // DMA now shares the IRQ handler with other system interrupts
ret_value = request_irq(i, dma_interrupt_handler, IRQF_DISABLED,
"dma channel", ch);
ret_value = ret_value;
//pr_debug(PR_PREFIX "Interrupt handler ret value for chan %d = %d\n", i, ret_value);
#endif
md_mic_dma_chan_setup(dma_ctx, ch);
mi_mic_dma_chan_setup(ch, dma_ctx);
init_waitqueue_head(&ch->intr_wq);
init_waitqueue_head(&ch->access_wq);
// Only mark owned channel to be available
atomic_set(&(ch->flags), CHAN_AVAILABLE);
md_mic_dma_print_debug(&dma_ctx->dma_dev, ch->chan);
} else {
ch->desc_ring = NULL;
}
}
/* Initialize last_allocated_dma_channel */
dma_ctx->last_allocated_dma_channel_num = -1;
//pr_debug(PR_PREFIX "Initialized the dma channels\n");
mic_dma_proc_init(dma_ctx);
return 0;
}