[PATCH 0/2] sh_eth: remove unused BE descriptor support

[PATCH 0/2] sh_eth: remove unused BE descriptor support

[Sergei Shtylyov]

Hello.

   Here's a set of 2 patches against DaveM's 'net-next.git' repo plus the
recently merged to 'net.git' repo fix for the 16-bit descriptor endianness.
We get rid of ~30 LoCs and ~300 bytes of code.

[1/2] sh_eth: remove EDMAC_BIG_ENDIAN
[2/2] sh_eth: get rid of {cpu|edmac}_to_{edmac|cpu}()

MBR, Sergei

[PATCH 1/2] sh_eth: remove EDMAC_BIG_ENDIAN

[Sergei Shtylyov]

Commit  71557a37adb5 ("[netdrvr] sh_eth: Add SH7619 support") added support
for the big-endian EDMAC descriptors. However, it was never used and never
worked right until the recent driver  fixes. I think we now  can just remove
this support,  it was only burdening the driver from the start. It should be
easy to do without disturbing the SH platform code, at least for now...

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

---
 drivers/net/ethernet/renesas/sh_eth.c |   18 ++----------------
 drivers/net/ethernet/renesas/sh_eth.h |    1 -
 include/linux/sh_eth.h                |    2 +-
 3 files changed, 3 insertions(+), 18 deletions(-)

Index: net-next/drivers/net/ethernet/renesas/sh_eth.c
=================================--- net-next.orig/drivers/net/ethernet/renesas/sh_eth.c
+++ net-next/drivers/net/ethernet/renesas/sh_eth.c
@@ -971,24 +971,12 @@ static void sh_eth_set_receive_align(str
 /* CPU <-> EDMAC endian convert */
 static inline __u32 cpu_to_edmac(struct sh_eth_private *mdp, u32 x)
 {
-	switch (mdp->edmac_endian) {
-	case EDMAC_LITTLE_ENDIAN:
-		return cpu_to_le32(x);
-	case EDMAC_BIG_ENDIAN:
-		return cpu_to_be32(x);
-	}
-	return x;
+	return cpu_to_le32(x);
 }
 
 static inline __u32 edmac_to_cpu(struct sh_eth_private *mdp, u32 x)
 {
-	switch (mdp->edmac_endian) {
-	case EDMAC_LITTLE_ENDIAN:
-		return le32_to_cpu(x);
-	case EDMAC_BIG_ENDIAN:
-		return be32_to_cpu(x);
-	}
-	return x;
+	return le32_to_cpu(x);
 }
 
 /* Program the hardware MAC address from dev->dev_addr. */
@@ -3097,8 +3085,6 @@ static int sh_eth_drv_probe(struct platf
 	/* get PHY ID */
 	mdp->phy_id = pd->phy;
 	mdp->phy_interface = pd->phy_interface;
-	/* EDMAC endian */
-	mdp->edmac_endian = pd->edmac_endian;
 	mdp->no_ether_link = pd->no_ether_link;
 	mdp->ether_link_active_low = pd->ether_link_active_low;
 
Index: net-next/drivers/net/ethernet/renesas/sh_eth.h
=================================--- net-next.orig/drivers/net/ethernet/renesas/sh_eth.h
+++ net-next/drivers/net/ethernet/renesas/sh_eth.h
@@ -513,7 +513,6 @@ struct sh_eth_private {
 	u32 cur_rx, dirty_rx;		/* Producer/consumer ring indices */
 	u32 cur_tx, dirty_tx;
 	u32 rx_buf_sz;			/* Based on MTU+slack. */
-	int edmac_endian;
 	struct napi_struct napi;
 	bool irq_enabled;
 	/* MII transceiver section. */
Index: net-next/include/linux/sh_eth.h
=================================--- net-next.orig/include/linux/sh_eth.h
+++ net-next/include/linux/sh_eth.h
@@ -4,7 +4,7 @@
 #include <linux/phy.h>
 #include <linux/if_ether.h>
 
-enum {EDMAC_LITTLE_ENDIAN, EDMAC_BIG_ENDIAN};
+enum {EDMAC_LITTLE_ENDIAN};
 
 struct sh_eth_plat_data {
 	int phy;

[PATCH 2/2] sh_eth: get rid of {cpu|edmac}_to_{edmac|cpu}()

[Sergei Shtylyov]

Now that {cpu|edmac}_to_{edmac|cpu}() functions boiled down to the mere
{cpu|le32}_to_{le32|cpu}() calls, there's no need for these functions
anymore, so just get rid of them.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

---
 drivers/net/ethernet/renesas/sh_eth.c |   72 +++++++++++++---------------------
 1 file changed, 29 insertions(+), 43 deletions(-)

Index: net-next/drivers/net/ethernet/renesas/sh_eth.c
=================================--- net-next.orig/drivers/net/ethernet/renesas/sh_eth.c
+++ net-next/drivers/net/ethernet/renesas/sh_eth.c
@@ -967,18 +967,6 @@ static void sh_eth_set_receive_align(str
 		skb_reserve(skb, SH_ETH_RX_ALIGN - reserve);
 }
 
-
-/* CPU <-> EDMAC endian convert */
-static inline __u32 cpu_to_edmac(struct sh_eth_private *mdp, u32 x)
-{
-	return cpu_to_le32(x);
-}
-
-static inline __u32 edmac_to_cpu(struct sh_eth_private *mdp, u32 x)
-{
-	return le32_to_cpu(x);
-}
-
 /* Program the hardware MAC address from dev->dev_addr. */
 static void update_mac_address(struct net_device *ndev)
 {
@@ -1152,7 +1140,7 @@ static void sh_eth_ring_format(struct ne
 		rxdesc = &mdp->rx_ring[i];
 		/* The size of the buffer is a multiple of 32 bytes. */
 		buf_len = ALIGN(mdp->rx_buf_sz, 32);
-		rxdesc->len = cpu_to_edmac(mdp, buf_len << 16);
+		rxdesc->len = cpu_to_le32(buf_len << 16);
 		dma_addr = dma_map_single(&ndev->dev, skb->data, buf_len,
 					  DMA_FROM_DEVICE);
 		if (dma_mapping_error(&ndev->dev, dma_addr)) {
@@ -1160,8 +1148,8 @@ static void sh_eth_ring_format(struct ne
 			break;
 		}
 		mdp->rx_skbuff[i] = skb;
-		rxdesc->addr = cpu_to_edmac(mdp, dma_addr);
-		rxdesc->status = cpu_to_edmac(mdp, RD_RACT | RD_RFP);
+		rxdesc->addr = cpu_to_le32(dma_addr);
+		rxdesc->status = cpu_to_le32(RD_RACT | RD_RFP);
 
 		/* Rx descriptor address set */
 		if (i = 0) {
@@ -1175,7 +1163,7 @@ static void sh_eth_ring_format(struct ne
 	mdp->dirty_rx = (u32) (i - mdp->num_rx_ring);
 
 	/* Mark the last entry as wrapping the ring. */
-	rxdesc->status |= cpu_to_edmac(mdp, RD_RDLE);
+	rxdesc->status |= cpu_to_le32(RD_RDLE);
 
 	memset(mdp->tx_ring, 0, tx_ringsize);
 
@@ -1183,8 +1171,8 @@ static void sh_eth_ring_format(struct ne
 	for (i = 0; i < mdp->num_tx_ring; i++) {
 		mdp->tx_skbuff[i] = NULL;
 		txdesc = &mdp->tx_ring[i];
-		txdesc->status = cpu_to_edmac(mdp, TD_TFP);
-		txdesc->len = cpu_to_edmac(mdp, 0);
+		txdesc->status = cpu_to_le32(TD_TFP);
+		txdesc->len = cpu_to_le32(0);
 		if (i = 0) {
 			/* Tx descriptor address set */
 			sh_eth_write(ndev, mdp->tx_desc_dma, TDLAR);
@@ -1194,7 +1182,7 @@ static void sh_eth_ring_format(struct ne
 		}
 	}
 
-	txdesc->status |= cpu_to_edmac(mdp, TD_TDLE);
+	txdesc->status |= cpu_to_le32(TD_TDLE);
 }
 
 /* Get skb and descriptor buffer */
@@ -1350,7 +1338,7 @@ static void sh_eth_dev_exit(struct net_d
 	 * packet boundary if it's currently running
 	 */
 	for (i = 0; i < mdp->num_tx_ring; i++)
-		mdp->tx_ring[i].status &= ~cpu_to_edmac(mdp, TD_TACT);
+		mdp->tx_ring[i].status &= ~cpu_to_le32(TD_TACT);
 
 	/* Disable TX FIFO egress to MAC */
 	sh_eth_rcv_snd_disable(ndev);
@@ -1382,29 +1370,28 @@ static int sh_eth_txfree(struct net_devi
 	for (; mdp->cur_tx - mdp->dirty_tx > 0; mdp->dirty_tx++) {
 		entry = mdp->dirty_tx % mdp->num_tx_ring;
 		txdesc = &mdp->tx_ring[entry];
-		if (txdesc->status & cpu_to_edmac(mdp, TD_TACT))
+		if (txdesc->status & cpu_to_le32(TD_TACT))
 			break;
 		/* TACT bit must be checked before all the following reads */
 		dma_rmb();
 		netif_info(mdp, tx_done, ndev,
 			   "tx entry %d status 0x%08x\n",
-			   entry, edmac_to_cpu(mdp, txdesc->status));
+			   entry, le32_to_cpu(txdesc->status));
 		/* Free the original skb. */
 		if (mdp->tx_skbuff[entry]) {
-			dma_unmap_single(&ndev->dev,
-					 edmac_to_cpu(mdp, txdesc->addr),
-					 edmac_to_cpu(mdp, txdesc->len) >> 16,
+			dma_unmap_single(&ndev->dev, le32_to_cpu(txdesc->addr),
+					 le32_to_cpu(txdesc->len) >> 16,
 					 DMA_TO_DEVICE);
 			dev_kfree_skb_irq(mdp->tx_skbuff[entry]);
 			mdp->tx_skbuff[entry] = NULL;
 			free_num++;
 		}
-		txdesc->status = cpu_to_edmac(mdp, TD_TFP);
+		txdesc->status = cpu_to_le32(TD_TFP);
 		if (entry >= mdp->num_tx_ring - 1)
-			txdesc->status |= cpu_to_edmac(mdp, TD_TDLE);
+			txdesc->status |= cpu_to_le32(TD_TDLE);
 
 		ndev->stats.tx_packets++;
-		ndev->stats.tx_bytes += edmac_to_cpu(mdp, txdesc->len) >> 16;
+		ndev->stats.tx_bytes += le32_to_cpu(txdesc->len) >> 16;
 	}
 	return free_num;
 }
@@ -1428,11 +1415,11 @@ static int sh_eth_rx(struct net_device *
 	boguscnt = min(boguscnt, *quota);
 	limit = boguscnt;
 	rxdesc = &mdp->rx_ring[entry];
-	while (!(rxdesc->status & cpu_to_edmac(mdp, RD_RACT))) {
+	while (!(rxdesc->status & cpu_to_le32(RD_RACT))) {
 		/* RACT bit must be checked before all the following reads */
 		dma_rmb();
-		desc_status = edmac_to_cpu(mdp, rxdesc->status);
-		pkt_len = edmac_to_cpu(mdp, rxdesc->len) & RD_RFL;
+		desc_status = le32_to_cpu(rxdesc->status);
+		pkt_len = le32_to_cpu(rxdesc->len) & RD_RFL;
 
 		if (--boguscnt < 0)
 			break;
@@ -1470,7 +1457,7 @@ static int sh_eth_rx(struct net_device *
 			if (desc_status & RD_RFS10)
 				ndev->stats.rx_over_errors++;
 		} else	if (skb) {
-			dma_addr = edmac_to_cpu(mdp, rxdesc->addr);
+			dma_addr = le32_to_cpu(rxdesc->addr);
 			if (!mdp->cd->hw_swap)
 				sh_eth_soft_swap(
 					phys_to_virt(ALIGN(dma_addr, 4)),
@@ -1499,7 +1486,7 @@ static int sh_eth_rx(struct net_device *
 		rxdesc = &mdp->rx_ring[entry];
 		/* The size of the buffer is 32 byte boundary. */
 		buf_len = ALIGN(mdp->rx_buf_sz, 32);
-		rxdesc->len = cpu_to_edmac(mdp, buf_len << 16);
+		rxdesc->len = cpu_to_le32(buf_len << 16);
 
 		if (mdp->rx_skbuff[entry] = NULL) {
 			skb = netdev_alloc_skb(ndev, skbuff_size);
@@ -1515,15 +1502,14 @@ static int sh_eth_rx(struct net_device *
 			mdp->rx_skbuff[entry] = skb;
 
 			skb_checksum_none_assert(skb);
-			rxdesc->addr = cpu_to_edmac(mdp, dma_addr);
+			rxdesc->addr = cpu_to_le32(dma_addr);
 		}
 		dma_wmb(); /* RACT bit must be set after all the above writes */
 		if (entry >= mdp->num_rx_ring - 1)
 			rxdesc->status |-				cpu_to_edmac(mdp, RD_RACT | RD_RFP | RD_RDLE);
+				cpu_to_le32(RD_RACT | RD_RFP | RD_RDLE);
 		else
-			rxdesc->status |-				cpu_to_edmac(mdp, RD_RACT | RD_RFP);
+			rxdesc->status |= cpu_to_le32(RD_RACT | RD_RFP);
 	}
 
 	/* Restart Rx engine if stopped. */
@@ -2323,8 +2309,8 @@ static void sh_eth_tx_timeout(struct net
 	/* Free all the skbuffs in the Rx queue. */
 	for (i = 0; i < mdp->num_rx_ring; i++) {
 		rxdesc = &mdp->rx_ring[i];
-		rxdesc->status = cpu_to_edmac(mdp, 0);
-		rxdesc->addr = cpu_to_edmac(mdp, 0xBADF00D0);
+		rxdesc->status = cpu_to_le32(0);
+		rxdesc->addr = cpu_to_le32(0xBADF00D0);
 		dev_kfree_skb(mdp->rx_skbuff[i]);
 		mdp->rx_skbuff[i] = NULL;
 	}
@@ -2372,14 +2358,14 @@ static int sh_eth_start_xmit(struct sk_b
 		kfree_skb(skb);
 		return NETDEV_TX_OK;
 	}
-	txdesc->addr = cpu_to_edmac(mdp, dma_addr);
-	txdesc->len  = cpu_to_edmac(mdp, skb->len << 16);
+	txdesc->addr = cpu_to_le32(dma_addr);
+	txdesc->len  = cpu_to_le32(skb->len << 16);
 
 	dma_wmb(); /* TACT bit must be set after all the above writes */
 	if (entry >= mdp->num_tx_ring - 1)
-		txdesc->status |= cpu_to_edmac(mdp, TD_TACT | TD_TDLE);
+		txdesc->status |= cpu_to_le32(TD_TACT | TD_TDLE);
 	else
-		txdesc->status |= cpu_to_edmac(mdp, TD_TACT);
+		txdesc->status |= cpu_to_le32(TD_TACT);
 
 	mdp->cur_tx++;
 

Re: [PATCH 1/2] sh_eth: remove EDMAC_BIG_ENDIAN

[Simon Horman]

On Mon, Dec 28, 2015 at 02:07:08AM +0300, Sergei Shtylyov wrote:
> Commit  71557a37adb5 ("[netdrvr] sh_eth: Add SH7619 support") added support
> for the big-endian EDMAC descriptors. However, it was never used and never
> worked right until the recent driver  fixes. I think we now  can just remove
> this support,  it was only burdening the driver from the start. It should be
> easy to do without disturbing the SH platform code, at least for now...
> 
> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

Acked-by: Simon Horman <horms+renesas@verge.net.au>

Re: [PATCH 2/2] sh_eth: get rid of {cpu|edmac}_to_{edmac|cpu}()

[Simon Horman]

On Mon, Dec 28, 2015 at 02:10:47AM +0300, Sergei Shtylyov wrote:
> Now that {cpu|edmac}_to_{edmac|cpu}() functions boiled down to the mere
> {cpu|le32}_to_{le32|cpu}() calls, there's no need for these functions
> anymore, so just get rid of them.
> 
> Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>

Acked-by: Simon Horman <horms+renesas@verge.net.au>

Re: [PATCH 0/2] sh_eth: remove unused BE descriptor support

[David Miller]

From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Date: Mon, 28 Dec 2015 02:05:24 +0300

>    Here's a set of 2 patches against DaveM's 'net-next.git' repo plus the
> recently merged to 'net.git' repo fix for the 16-bit descriptor endianness.
> We get rid of ~30 LoCs and ~300 bytes of code.

Series applied, thanks Sergei.