[PATCH 4/9] qtnfmac: skb2rbd_attach cleanup

[Sergey Matyukevich]

Update PCIE_HDP_TX_HOST_Q_WR_PTR register in skb2rbd_attach as a part of
procedure of passing new Rx buffer to hardware. Sync up all the the
qtnf_rx_bd descriptor updates before passing Rx buffer to hardware.

Signed-off-by: Sergey Matyukevich <sergey.matyukevich...@quantenna.com>
---
 .../net/wireless/quantenna/qtnfmac/pearl/pcie.c    | 31 +++++++++-------------
 1 file changed, 13 insertions(+), 18 deletions(-)

diff --git a/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c 
b/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
index 079aa1693ff5..a0b65d487ddb 100644
--- a/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
@@ -411,11 +411,6 @@ static int alloc_bd_table(struct qtnf_pcie_bus_priv *priv)
        writel(priv->rx_bd_num | (sizeof(struct qtnf_rx_bd)) << 16,
               PCIE_HDP_TX_HOST_Q_SZ_CTRL(priv->pcie_reg_base));
 
-       priv->hw_txproc_wr_ptr = priv->rx_bd_num - rx_bd_reserved_param;
-
-       writel(priv->hw_txproc_wr_ptr,
-              PCIE_HDP_TX_HOST_Q_WR_PTR(priv->pcie_reg_base));
-
        pr_debug("RX descriptor table: vaddr=0x%p paddr=%pad\n", vaddr, &paddr);
 
        priv->rx_bd_index = 0;
@@ -423,7 +418,7 @@ static int alloc_bd_table(struct qtnf_pcie_bus_priv *priv)
        return 0;
 }
 
-static int skb2rbd_attach(struct qtnf_pcie_bus_priv *priv, u16 rx_bd_index)
+static int skb2rbd_attach(struct qtnf_pcie_bus_priv *priv, u16 index)
 {
        struct qtnf_rx_bd *rxbd;
        struct sk_buff *skb;
@@ -431,13 +426,12 @@ static int skb2rbd_attach(struct qtnf_pcie_bus_priv 
*priv, u16 rx_bd_index)
 
        skb = __netdev_alloc_skb_ip_align(NULL, SKB_BUF_SIZE, GFP_ATOMIC);
        if (!skb) {
-               priv->rx_skb[rx_bd_index] = NULL;
+               priv->rx_skb[index] = NULL;
                return -ENOMEM;
        }
 
-       priv->rx_skb[rx_bd_index] = skb;
-
-       rxbd = &priv->rx_bd_vbase[rx_bd_index];
+       priv->rx_skb[index] = skb;
+       rxbd = &priv->rx_bd_vbase[index];
 
        paddr = pci_map_single(priv->pdev, skb->data,
                               SKB_BUF_SIZE, PCI_DMA_FROMDEVICE);
@@ -446,17 +440,20 @@ static int skb2rbd_attach(struct qtnf_pcie_bus_priv 
*priv, u16 rx_bd_index)
                return -ENOMEM;
        }
 
-       writel(QTN_HOST_LO32(paddr),
-              PCIE_HDP_HHBM_BUF_PTR(priv->pcie_reg_base));
-       writel(QTN_HOST_HI32(paddr),
-              PCIE_HDP_HHBM_BUF_PTR_H(priv->pcie_reg_base));
-
        /* keep rx skb paddrs in rx buffer descriptors for cleanup purposes */
        rxbd->addr = cpu_to_le32(QTN_HOST_LO32(paddr));
        rxbd->addr_h = cpu_to_le32(QTN_HOST_HI32(paddr));
-
        rxbd->info = 0x0;
 
+       /* sync up all descriptor updates */
+       wmb();
+
+       writel(QTN_HOST_HI32(paddr),
+              PCIE_HDP_HHBM_BUF_PTR_H(priv->pcie_reg_base));
+       writel(QTN_HOST_LO32(paddr),
+              PCIE_HDP_HHBM_BUF_PTR(priv->pcie_reg_base));
+
+       writel(index, PCIE_HDP_TX_HOST_Q_WR_PTR(priv->pcie_reg_base));
        return 0;
 }
 
@@ -787,8 +784,6 @@ static int qtnf_rx_poll(struct napi_struct *napi, int 
budget)
                        break;
                }
 
-               writel(priv->hw_txproc_wr_ptr,
-                      PCIE_HDP_TX_HOST_Q_WR_PTR(priv->pcie_reg_base));
        }
 
        if (processed < budget) {
-- 
2.11.0