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net: bcmgenet: core changes for supporting multiple Rx queues
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1. Add struct bcmgenet_rx_ring to hold all necessary information
   for a single Rx queue.
2. Add bcmgenet_init_rx_queues() to initialize all Rx queues.
3. Modify bcmgenet_init_rx_ring() to initialize a single Rx queue.
4. Modify Rx interrupt path code to use per-queue data.
5. Modify bcmgenet_rx_refill() to use RxCB->bd_addr.

Signed-off-by: Petri Gynther <pgynther@google.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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@davem330
Petri Gynther authored and davem330 committed Mar 10, 2015
1 parent 115403d commit 8ac467e
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Showing 2 changed files with 119 additions and 53 deletions.
156 changes: 107 additions & 49 deletions drivers/net/ethernet/broadcom/genet/bcmgenet.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1363,16 +1363,7 @@ static int bcmgenet_rx_refill(struct bcmgenet_priv *priv, struct enet_cb *cb)
}

dma_unmap_addr_set(cb, dma_addr, mapping);
/* assign packet, prepare descriptor, and advance pointer */

dmadesc_set_addr(priv, priv->rx_bd_assign_ptr, mapping);

/* turn on the newly assigned BD for DMA to use */
priv->rx_bd_assign_index++;
priv->rx_bd_assign_index &= (priv->num_rx_bds - 1);

priv->rx_bd_assign_ptr = priv->rx_bds +
(priv->rx_bd_assign_index * DMA_DESC_SIZE);
dmadesc_set_addr(priv, cb->bd_addr, mapping);

return 0;
}
Expand All @@ -1381,8 +1372,10 @@ static int bcmgenet_rx_refill(struct bcmgenet_priv *priv, struct enet_cb *cb)
* this could be called from bottom half, or from NAPI polling method.
*/
static unsigned int bcmgenet_desc_rx(struct bcmgenet_priv *priv,
unsigned int index,
unsigned int budget)
{
struct bcmgenet_rx_ring *ring = &priv->rx_rings[index];
struct net_device *dev = priv->dev;
struct enet_cb *cb;
struct sk_buff *skb;
Expand All @@ -1393,21 +1386,21 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_priv *priv,
unsigned int p_index;
unsigned int chksum_ok = 0;

p_index = bcmgenet_rdma_ring_readl(priv, DESC_INDEX, RDMA_PROD_INDEX);
p_index = bcmgenet_rdma_ring_readl(priv, index, RDMA_PROD_INDEX);
p_index &= DMA_P_INDEX_MASK;

if (p_index < priv->rx_c_index)
rxpkttoprocess = (DMA_C_INDEX_MASK + 1) -
priv->rx_c_index + p_index;
if (likely(p_index >= ring->c_index))
rxpkttoprocess = p_index - ring->c_index;
else
rxpkttoprocess = p_index - priv->rx_c_index;
rxpkttoprocess = (DMA_C_INDEX_MASK + 1) - ring->c_index +
p_index;

netif_dbg(priv, rx_status, dev,
"RDMA: rxpkttoprocess=%d\n", rxpkttoprocess);

while ((rxpktprocessed < rxpkttoprocess) &&
(rxpktprocessed < budget)) {
cb = &priv->rx_cbs[priv->rx_read_ptr];
cb = &priv->rx_cbs[ring->read_ptr];
skb = cb->skb;

/* We do not have a backing SKB, so we do not have a
Expand All @@ -1430,10 +1423,7 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_priv *priv,

if (!priv->desc_64b_en) {
dma_length_status =
dmadesc_get_length_status(priv,
priv->rx_bds +
(priv->rx_read_ptr *
DMA_DESC_SIZE));
dmadesc_get_length_status(priv, cb->bd_addr);
} else {
struct status_64 *status;

Expand All @@ -1449,8 +1439,8 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_priv *priv,

netif_dbg(priv, rx_status, dev,
"%s:p_ind=%d c_ind=%d read_ptr=%d len_stat=0x%08x\n",
__func__, p_index, priv->rx_c_index,
priv->rx_read_ptr, dma_length_status);
__func__, p_index, ring->c_index,
ring->read_ptr, dma_length_status);

if (unlikely(!(dma_flag & DMA_EOP) || !(dma_flag & DMA_SOP))) {
netif_err(priv, rx_status, dev,
Expand Down Expand Up @@ -1528,25 +1518,31 @@ static unsigned int bcmgenet_desc_rx(struct bcmgenet_priv *priv,
}

rxpktprocessed++;
priv->rx_read_ptr++;
priv->rx_read_ptr &= (priv->num_rx_bds - 1);
if (likely(ring->read_ptr < ring->end_ptr))
ring->read_ptr++;
else
ring->read_ptr = ring->cb_ptr;

ring->c_index = (ring->c_index + 1) & DMA_C_INDEX_MASK;
bcmgenet_rdma_ring_writel(priv, index, ring->c_index, RDMA_CONS_INDEX);
}

return rxpktprocessed;
}

/* Assign skb to RX DMA descriptor. */
static int bcmgenet_alloc_rx_buffers(struct bcmgenet_priv *priv)
static int bcmgenet_alloc_rx_buffers(struct bcmgenet_priv *priv,
struct bcmgenet_rx_ring *ring)
{
struct enet_cb *cb;
int ret = 0;
int i;

netif_dbg(priv, hw, priv->dev, "%s:\n", __func__);
netif_dbg(priv, hw, priv->dev, "%s\n", __func__);

/* loop here for each buffer needing assign */
for (i = 0; i < priv->num_rx_bds; i++) {
cb = &priv->rx_cbs[priv->rx_bd_assign_index];
for (i = 0; i < ring->size; i++) {
cb = ring->cbs + i;
if (cb->skb)
continue;

Expand Down Expand Up @@ -1778,20 +1774,24 @@ static void bcmgenet_fini_tx_ring(struct bcmgenet_priv *priv,

/* Initialize a RDMA ring */
static int bcmgenet_init_rx_ring(struct bcmgenet_priv *priv,
unsigned int index, unsigned int size)
unsigned int index, unsigned int size,
unsigned int start_ptr, unsigned int end_ptr)
{
struct bcmgenet_rx_ring *ring = &priv->rx_rings[index];
u32 words_per_bd = WORDS_PER_BD(priv);
int ret;

priv->rx_bd_assign_ptr = priv->rx_bds;
priv->rx_bd_assign_index = 0;
priv->rx_c_index = 0;
priv->rx_read_ptr = 0;
ring->index = index;
ring->cbs = priv->rx_cbs + start_ptr;
ring->size = size;
ring->c_index = 0;
ring->read_ptr = start_ptr;
ring->cb_ptr = start_ptr;
ring->end_ptr = end_ptr - 1;

ret = bcmgenet_alloc_rx_buffers(priv);
if (ret) {
ret = bcmgenet_alloc_rx_buffers(priv, ring);
if (ret)
return ret;
}

bcmgenet_rdma_ring_writel(priv, index, 0, RDMA_PROD_INDEX);
bcmgenet_rdma_ring_writel(priv, index, 0, RDMA_CONS_INDEX);
Expand All @@ -1805,10 +1805,13 @@ static int bcmgenet_init_rx_ring(struct bcmgenet_priv *priv,
DMA_FC_THRESH_HI, RDMA_XON_XOFF_THRESH);

/* Set start and end address, read and write pointers */
bcmgenet_rdma_ring_writel(priv, index, 0, DMA_START_ADDR);
bcmgenet_rdma_ring_writel(priv, index, 0, RDMA_READ_PTR);
bcmgenet_rdma_ring_writel(priv, index, 0, RDMA_WRITE_PTR);
bcmgenet_rdma_ring_writel(priv, index, words_per_bd * size - 1,
bcmgenet_rdma_ring_writel(priv, index, start_ptr * words_per_bd,
DMA_START_ADDR);
bcmgenet_rdma_ring_writel(priv, index, start_ptr * words_per_bd,
RDMA_READ_PTR);
bcmgenet_rdma_ring_writel(priv, index, start_ptr * words_per_bd,
RDMA_WRITE_PTR);
bcmgenet_rdma_ring_writel(priv, index, end_ptr * words_per_bd - 1,
DMA_END_ADDR);

return ret;
Expand Down Expand Up @@ -1883,6 +1886,66 @@ static void bcmgenet_init_tx_queues(struct net_device *dev)
bcmgenet_tdma_writel(priv, dma_ctrl, DMA_CTRL);
}

/* Initialize Rx queues
*
* Queues 0-15 are priority queues. Hardware Filtering Block (HFB) can be
* used to direct traffic to these queues.
*
* Queue 16 is the default Rx queue with GENET_Q16_RX_BD_CNT descriptors.
*/
static int bcmgenet_init_rx_queues(struct net_device *dev)
{
struct bcmgenet_priv *priv = netdev_priv(dev);
u32 i;
u32 dma_enable;
u32 dma_ctrl;
u32 ring_cfg;
int ret;

dma_ctrl = bcmgenet_rdma_readl(priv, DMA_CTRL);
dma_enable = dma_ctrl & DMA_EN;
dma_ctrl &= ~DMA_EN;
bcmgenet_rdma_writel(priv, dma_ctrl, DMA_CTRL);

dma_ctrl = 0;
ring_cfg = 0;

/* Initialize Rx priority queues */
for (i = 0; i < priv->hw_params->rx_queues; i++) {
ret = bcmgenet_init_rx_ring(priv, i,
priv->hw_params->rx_bds_per_q,
i * priv->hw_params->rx_bds_per_q,
(i + 1) *
priv->hw_params->rx_bds_per_q);
if (ret)
return ret;

ring_cfg |= (1 << i);
dma_ctrl |= (1 << (i + DMA_RING_BUF_EN_SHIFT));
}

/* Initialize Rx default queue 16 */
ret = bcmgenet_init_rx_ring(priv, DESC_INDEX, GENET_Q16_RX_BD_CNT,
priv->hw_params->rx_queues *
priv->hw_params->rx_bds_per_q,
TOTAL_DESC);
if (ret)
return ret;

ring_cfg |= (1 << DESC_INDEX);
dma_ctrl |= (1 << (DESC_INDEX + DMA_RING_BUF_EN_SHIFT));

/* Enable rings */
bcmgenet_rdma_writel(priv, ring_cfg, DMA_RING_CFG);

/* Configure ring as descriptor ring and re-enable DMA if enabled */
if (dma_enable)
dma_ctrl |= DMA_EN;
bcmgenet_rdma_writel(priv, dma_ctrl, DMA_CTRL);

return 0;
}

static int bcmgenet_dma_teardown(struct bcmgenet_priv *priv)
{
int ret = 0;
Expand Down Expand Up @@ -1990,10 +2053,10 @@ static int bcmgenet_init_dma(struct bcmgenet_priv *priv)
cb->bd_addr = priv->rx_bds + i * DMA_DESC_SIZE;
}

/* Initialize Rx default queue 16 */
ret = bcmgenet_init_rx_ring(priv, DESC_INDEX, TOTAL_DESC);
/* Initialize Rx queues */
ret = bcmgenet_init_rx_queues(priv->dev);
if (ret) {
netdev_err(priv->dev, "failed to initialize RX ring\n");
netdev_err(priv->dev, "failed to initialize Rx queues\n");
bcmgenet_free_rx_buffers(priv);
kfree(priv->rx_cbs);
return ret;
Expand Down Expand Up @@ -2030,13 +2093,8 @@ static int bcmgenet_poll(struct napi_struct *napi, int budget)
struct bcmgenet_priv, napi);
unsigned int work_done;

work_done = bcmgenet_desc_rx(priv, budget);
work_done = bcmgenet_desc_rx(priv, DESC_INDEX, budget);

/* Advancing our consumer index*/
priv->rx_c_index += work_done;
priv->rx_c_index &= DMA_C_INDEX_MASK;
bcmgenet_rdma_ring_writel(priv, DESC_INDEX,
priv->rx_c_index, RDMA_CONS_INDEX);
if (work_done < budget) {
napi_complete(napi);
bcmgenet_intrl2_0_writel(priv, UMAC_IRQ_RXDMA_BDONE,
Expand Down
16 changes: 12 additions & 4 deletions drivers/net/ethernet/broadcom/genet/bcmgenet.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -540,6 +540,16 @@ struct bcmgenet_tx_ring {
struct bcmgenet_priv *priv;
};

struct bcmgenet_rx_ring {
unsigned int index; /* Rx ring index */
struct enet_cb *cbs; /* Rx ring buffer control block */
unsigned int size; /* Rx ring size */
unsigned int c_index; /* Rx last consumer index */
unsigned int read_ptr; /* Rx ring read pointer */
unsigned int cb_ptr; /* Rx ring initial CB ptr */
unsigned int end_ptr; /* Rx ring end CB ptr */
};

/* device context */
struct bcmgenet_priv {
void __iomem *base;
Expand All @@ -560,13 +570,11 @@ struct bcmgenet_priv {

/* receive variables */
void __iomem *rx_bds;
void __iomem *rx_bd_assign_ptr;
int rx_bd_assign_index;
struct enet_cb *rx_cbs;
unsigned int num_rx_bds;
unsigned int rx_buf_len;
unsigned int rx_read_ptr;
unsigned int rx_c_index;

struct bcmgenet_rx_ring rx_rings[DESC_INDEX + 1];

/* other misc variables */
struct bcmgenet_hw_params *hw_params;
Expand Down

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