net: sparx5: use the FDMA library for allocation of rx buffers

Use the two functions: fdma_alloc_phys() and fdma_dcb_init() for rx
buffer allocation and use the new buffers throughout.

In order to replace the old buffers with the new ones, we have to do the
following refactoring:

    - use fdma_alloc_phys() and fdma_dcb_init()

    - replace the variables: rx->dma, rx->dcb_entries and rx->last_entry
      with the equivalents from the FDMA struct.

    - replace uses of sparx5_db_hw and sparx5_rx_dcb_hw with fdma_db and
      fdma_dcb.

    - add sparx5_fdma_rx_dataptr_cb callback for obtaining the dataptr.

    - Initialize FDMA struct values.

Signed-off-by: Daniel Machon <daniel.machon@microchip.com>
Reviewed-by: Steen Hegelund <Steen.Hegelund@microchip.com>
Reviewed-by: Jens Emil Schulz Østergaard <jensemil.schulzostergaard@microchip.com>
Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c b/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
index 5e058dbc734e11c9cfd47cf7dd6b24ef81a7207a..675f8d5faa74a83a3eedeaa374caee35ebc6534b 100644 (file)
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_fdma.c
@@ -32,8 +32,26 @@ struct sparx5_db {
        void *cpu_addr;
 };
 
+static int sparx5_fdma_rx_dataptr_cb(struct fdma *fdma, int dcb, int db,
+                                    u64 *dataptr)
+{
+       struct sparx5 *sparx5 = fdma->priv;
+       struct sparx5_rx *rx = &sparx5->rx;
+       struct sk_buff *skb;
+
+       skb = __netdev_alloc_skb(rx->ndev, fdma->db_size, GFP_ATOMIC);
+       if (unlikely(!skb))
+               return -ENOMEM;
+
+       *dataptr = virt_to_phys(skb->data);
+
+       rx->skb[dcb][db] = skb;
+
+       return 0;
+}
+
 static void sparx5_fdma_rx_add_dcb(struct sparx5_rx *rx,
-                                  struct sparx5_rx_dcb_hw *dcb,
+                                  struct fdma_dcb *dcb,
                                   u64 nextptr)
 {
        struct fdma *fdma = &rx->fdma;
@@ -41,14 +59,15 @@ static void sparx5_fdma_rx_add_dcb(struct sparx5_rx *rx,
 
        /* Reset the status of the DB */
        for (idx = 0; idx < fdma->n_dbs; ++idx) {
-               struct sparx5_db_hw *db = &dcb->db[idx];
+               struct fdma_db *db = &dcb->db[idx];
 
                db->status = FDMA_DCB_STATUS_INTR;
        }
        dcb->nextptr = FDMA_DCB_INVALID_DATA;
        dcb->info = FDMA_DCB_INFO_DATAL(FDMA_XTR_BUFFER_SIZE);
-       rx->last_entry->nextptr = nextptr;
-       rx->last_entry = dcb;
+
+       fdma->last_dcb->nextptr = nextptr;
+       fdma->last_dcb = dcb;
 }
 
 static void sparx5_fdma_tx_add_dcb(struct sparx5_tx *tx,
@@ -72,9 +91,10 @@ static void sparx5_fdma_rx_activate(struct sparx5 *sparx5, struct sparx5_rx *rx)
        struct fdma *fdma = &rx->fdma;
 
        /* Write the buffer address in the LLP and LLP1 regs */
-       spx5_wr(((u64)rx->dma) & GENMASK(31, 0), sparx5,
+       spx5_wr(((u64)fdma->dma) & GENMASK(31, 0), sparx5,
                FDMA_DCB_LLP(fdma->channel_id));
-       spx5_wr(((u64)rx->dma) >> 32, sparx5, FDMA_DCB_LLP1(fdma->channel_id));
+       spx5_wr(((u64)fdma->dma) >> 32, sparx5,
+               FDMA_DCB_LLP1(fdma->channel_id));
 
        /* Set the number of RX DBs to be used, and DB end-of-frame interrupt */
        spx5_wr(FDMA_CH_CFG_CH_DCB_DB_CNT_SET(fdma->n_dbs) |
@@ -168,16 +188,16 @@ static struct sk_buff *sparx5_fdma_rx_alloc_skb(struct sparx5_rx *rx)
 static bool sparx5_fdma_rx_get_frame(struct sparx5 *sparx5, struct sparx5_rx *rx)
 {
        struct fdma *fdma = &rx->fdma;
-       struct sparx5_db_hw *db_hw;
        unsigned int packet_size;
        struct sparx5_port *port;
        struct sk_buff *new_skb;
+       struct fdma_db *db_hw;
        struct frame_info fi;
        struct sk_buff *skb;
        dma_addr_t dma_addr;
 
        /* Check if the DCB is done */
-       db_hw = &rx->dcb_entries[fdma->dcb_index].db[fdma->db_index];
+       db_hw = &fdma->dcbs[fdma->dcb_index].db[fdma->db_index];
        if (unlikely(!(db_hw->status & FDMA_DCB_STATUS_DONE)))
                return false;
        skb = rx->skb[fdma->dcb_index][fdma->db_index];
@@ -227,7 +247,7 @@ static int sparx5_fdma_napi_callback(struct napi_struct *napi, int weight)
        int counter = 0;
 
        while (counter < weight && sparx5_fdma_rx_get_frame(sparx5, rx)) {
-               struct sparx5_rx_dcb_hw *old_dcb;
+               struct fdma_dcb *old_dcb;
 
                fdma->db_index++;
                counter++;
@@ -238,13 +258,13 @@ static int sparx5_fdma_napi_callback(struct napi_struct *napi, int weight)
                 * pointer and set the nextptr in the DCB
                 */
                fdma->db_index = 0;
-               old_dcb = &rx->dcb_entries[fdma->dcb_index];
+               old_dcb = &fdma->dcbs[fdma->dcb_index];
                fdma->dcb_index++;
                fdma->dcb_index &= fdma->n_dcbs - 1;
                sparx5_fdma_rx_add_dcb(rx, old_dcb,
-                                      rx->dma +
+                                      fdma->dma +
                                       ((unsigned long)old_dcb -
-                                       (unsigned long)rx->dcb_entries));
+                                       (unsigned long)fdma->dcbs));
        }
        if (counter < weight) {
                napi_complete_done(&rx->napi, counter);
@@ -311,43 +331,15 @@ static int sparx5_fdma_rx_alloc(struct sparx5 *sparx5)
 {
        struct sparx5_rx *rx = &sparx5->rx;
        struct fdma *fdma = &rx->fdma;
-       struct sparx5_rx_dcb_hw *dcb;
-       int idx, jdx;
-       int size;
+       int err;
 
-       size = sizeof(struct sparx5_rx_dcb_hw) * fdma->n_dcbs;
-       size = ALIGN(size, PAGE_SIZE);
-       rx->dcb_entries = devm_kzalloc(sparx5->dev, size, GFP_KERNEL);
-       if (!rx->dcb_entries)
-               return -ENOMEM;
-       rx->dma = virt_to_phys(rx->dcb_entries);
-       rx->last_entry = rx->dcb_entries;
-       fdma->db_index = 0;
-       fdma->dcb_index = 0;
-       /* Now for each dcb allocate the db */
-       for (idx = 0; idx < fdma->n_dcbs; ++idx) {
-               dcb = &rx->dcb_entries[idx];
-               dcb->info = 0;
-               /* For each db allocate an skb and map skb data pointer to the DB
-                * dataptr. In this way when the frame is received the skb->data
-                * will contain the frame, so no memcpy is needed
-                */
-               for (jdx = 0; jdx < fdma->n_dbs; ++jdx) {
-                       struct sparx5_db_hw *db_hw = &dcb->db[jdx];
-                       dma_addr_t dma_addr;
-                       struct sk_buff *skb;
+       err = fdma_alloc_phys(fdma);
+       if (err)
+               return err;
 
-                       skb = sparx5_fdma_rx_alloc_skb(rx);
-                       if (!skb)
-                               return -ENOMEM;
+       fdma_dcbs_init(fdma, FDMA_DCB_INFO_DATAL(fdma->db_size),
+                      FDMA_DCB_STATUS_INTR);
 
-                       dma_addr = virt_to_phys(skb->data);
-                       db_hw->dataptr = dma_addr;
-                       db_hw->status = 0;
-                       rx->skb[idx][jdx] = skb;
-               }
-               sparx5_fdma_rx_add_dcb(rx, dcb, rx->dma + sizeof(*dcb) * idx);
-       }
        netif_napi_add_weight(rx->ndev, &rx->napi, sparx5_fdma_napi_callback,
                              FDMA_WEIGHT);
        napi_enable(&rx->napi);
@@ -413,6 +405,11 @@ static void sparx5_fdma_rx_init(struct sparx5 *sparx5,
        fdma->channel_id = channel;
        fdma->n_dcbs = FDMA_DCB_MAX;
        fdma->n_dbs = FDMA_RX_DCB_MAX_DBS;
+       fdma->priv = sparx5;
+       fdma->db_size = ALIGN(FDMA_XTR_BUFFER_SIZE, PAGE_SIZE);
+       fdma->size = fdma_get_size(&sparx5->rx.fdma);
+       fdma->ops.dataptr_cb = &sparx5_fdma_rx_dataptr_cb;
+       fdma->ops.nextptr_cb = &fdma_nextptr_cb;
        /* Fetch a netdev for SKB and NAPI use, any will do */
        for (idx = 0; idx < SPX5_PORTS; ++idx) {
                struct sparx5_port *port = sparx5->ports[idx];

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
index 542f57569c5f05847669c618e25cfcd47bdba4d7..1f57739b601cf6c5eda117e45aa584c4c282ba61 100644 (file)
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h
@@ -107,12 +107,6 @@ struct sparx5_db_hw {
        u64 status;
 };
 
-struct sparx5_rx_dcb_hw {
-       u64 nextptr;
-       u64 info;
-       struct sparx5_db_hw db[FDMA_RX_DCB_MAX_DBS];
-};
-
 struct sparx5_tx_dcb_hw {
        u64 nextptr;
        u64 info;
@@ -127,8 +121,6 @@ struct sparx5_tx_dcb_hw {
  */
 struct sparx5_rx {
        struct fdma fdma;
-       struct sparx5_rx_dcb_hw *dcb_entries;
-       struct sparx5_rx_dcb_hw *last_entry;
        struct sk_buff *skb[FDMA_DCB_MAX][FDMA_RX_DCB_MAX_DBS];
        dma_addr_t dma;
        struct napi_struct napi;