Hello!
On 4/17/2018 11:50 AM, Simon Horman wrote:
From: Kazuya Mizuguchi <kazuya.mizuguchi...@renesas.com>
This patch sets from two descriptor to one descriptor because R-Car Gen3
does not have the 4 bytes alignment restriction of the transmission buffer.
Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi...@renesas.com>
Signed-off-by: Simon Horman <horms+rene...@verge.net.au>
[...]
diff --git a/drivers/net/ethernet/renesas/ravb.h
b/drivers/net/ethernet/renesas/ravb.h
index fcd04dbc7dde..3d0985305c26 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h
@@ -964,7 +964,10 @@ enum RAVB_QUEUE {
#define RX_QUEUE_OFFSET 4
#define NUM_RX_QUEUE 2
#define NUM_TX_QUEUE 2
-#define NUM_TX_DESC 2 /* TX descriptors per packet */
+
+/* TX descriptors per packet */
+#define NUM_TX_DESC_GEN2 2
+#define NUM_TX_DESC_GEN3 1
We hanrdly need these...
struct ravb_tstamp_skb {
struct list_head list;
[...]
diff --git a/drivers/net/ethernet/renesas/ravb_main.c
b/drivers/net/ethernet/renesas/ravb_main.c
index 88056dd912ed..f137b62d5b52 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -189,12 +189,13 @@ static int ravb_tx_free(struct net_device *ndev, int q,
bool free_txed_only)
int free_num = 0;
int entry;
u32 size;
+ int num_tx_desc = priv->num_tx_desc;
Please keep sorting the declarations by length -- that's DaveM's pet peeve
(and indeed looks prettier. :-)
[...]
@@ -229,6 +230,7 @@ static void ravb_ring_free(struct net_device *ndev, int q)
struct ravb_private *priv = netdev_priv(ndev);
int ring_size;
int i;
+ int num_tx_desc = priv->num_tx_desc;
Here as well.
if (priv->rx_ring[q]) {
for (i = 0; i < priv->num_rx_ring[q]; i++) {
[...]
@@ -321,8 +324,10 @@ static void ravb_ring_format(struct net_device *ndev, int
q)
for (i = 0, tx_desc = priv->tx_ring[q]; i < priv->num_tx_ring[q];
i++, tx_desc++) {
tx_desc->die_dt = DT_EEMPTY;
- tx_desc++;
- tx_desc->die_dt = DT_EEMPTY;
+ if (num_tx_desc >= 2) {
> 1, please.
Strictly speaking, this only works when num_tx_desc == 2, however that's
my fault...
+ tx_desc++;
+ tx_desc->die_dt = DT_EEMPTY;
+ }
}
tx_desc->dptr = cpu_to_le32((u32)priv->tx_desc_dma[q]);
tx_desc->die_dt = DT_LINKFIX; /* type */
@@ -345,6 +350,7 @@ static int ravb_ring_init(struct net_device *ndev, int q)
struct sk_buff *skb;
int ring_size;
int i;
+ int num_tx_desc = priv->num_tx_desc;
Again, please keep the descarations sorted by length.
priv->rx_buf_sz = (ndev->mtu <= 1492 ? PKT_BUF_SZ : ndev->mtu) +
ETH_HLEN + VLAN_HLEN;
[...]
@@ -1533,10 +1539,11 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb,
struct net_device *ndev)
void *buffer;
u32 entry;
u32 len;
+ int num_tx_desc = priv->num_tx_desc;
Here as well...
[...]
@@ -1547,41 +1554,55 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb,
struct net_device *ndev)
[...]
+ entry = priv->cur_tx[q] % (priv->num_tx_ring[q] * num_tx_desc);
+ priv->tx_skb[q][entry / num_tx_desc] = skb;
+
+ if (num_tx_desc >= 2) {
> 1, please.
[...]
@@ -1589,9 +1610,11 @@ static netdev_tx_t ravb_start_xmit(struct sk_buff *skb,
struct net_device *ndev)
if (q == RAVB_NC) {
ts_skb = kmalloc(sizeof(*ts_skb), GFP_ATOMIC);
if (!ts_skb) {
- desc--;
- dma_unmap_single(ndev->dev.parent, dma_addr, len,
- DMA_TO_DEVICE);
+ if (num_tx_desc >= 2) {
Likewise.
+ desc--;
+ dma_unmap_single(ndev->dev.parent, dma_addr,
+ len, DMA_TO_DEVICE);
+ }
goto unmap;
}
ts_skb->skb = skb;
[...]
@@ -2106,6 +2132,9 @@ static int ravb_probe(struct platform_device *pdev)
ndev->max_mtu = 2048 - (ETH_HLEN + VLAN_HLEN + ETH_FCS_LEN);
ndev->min_mtu = ETH_MIN_MTU;
+ priv->num_tx_desc = (chip_id == RCAR_GEN2) ?
Parens not needed.
+ NUM_TX_DESC_GEN2 : NUM_TX_DESC_GEN3;
Just 2 : 1;
[...]
However... I'm not seeing this patch disabling memory allocation for
priv->tx_align[] and reducing the memory pressure is one of 2 reasons for this
patch, isn't it?
MBR, Sergei
