[PATCH 1/4] net: hix5hd2_gmac: add tx scatter-gather feature

From: Dongpo Li
Date: Thu Aug 11 2016 - 05:07:39 EST

From: Li Dongpo <lidongpo@xxxxxxxxxxxxx>

The "hix5hd2" is SoC name, add the generic ethernet driver name.
The "hisi-gemac-v1" is the basic version and "hisi-gemac-v2" adds
the SG/TXCSUM/TSO/UFO features.
This patch only adds the SG(scatter-gather) driver for transmitting,
the drivers of other features will be submitted later.

Signed-off-by: Dongpo Li <lidongpo@xxxxxxxxxxxxx>
---
.../bindings/net/hisilicon-hix5hd2-gmac.txt | 9 +-
drivers/net/ethernet/hisilicon/hix5hd2_gmac.c | 213 +++++++++++++++++++--
2 files changed, 205 insertions(+), 17 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt b/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt
index 75d398b..3c02fac 100644
--- a/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt
+++ b/Documentation/devicetree/bindings/net/hisilicon-hix5hd2-gmac.txt
@@ -1,7 +1,12 @@
Hisilicon hix5hd2 gmac controller

Required properties:
-- compatible: should be "hisilicon,hix5hd2-gmac".
+- compatible: should contain one of the following version strings:
+ * "hisilicon,hisi-gemac-v1"
+ * "hisilicon,hisi-gemac-v2"
+ and one of the following SoC string:
+ * "hisilicon,hix5hd2-gemac"
+ * "hisilicon,hi3798cv200-gemac"
- reg: specifies base physical address(s) and size of the device registers.
The first region is the MAC register base and size.
The second region is external interface control register.
@@ -20,7 +25,7 @@ Required properties:

Example:
gmac0: ethernet@f9840000 {
- compatible = "hisilicon,hix5hd2-gmac";
+ compatible = "hisilicon,hix5hd2-gemac", "hisilicon,hisi-gemac-v1";
reg = <0xf9840000 0x1000>,<0xf984300c 0x4>;
interrupts = <0 71 4>;
#address-cells = <1>;
diff --git a/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c b/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
index 275618b..679a5e5 100644
--- a/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
+++ b/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
@@ -11,6 +11,7 @@
#include <linux/interrupt.h>
#include <linux/etherdevice.h>
#include <linux/platform_device.h>
+#include <linux/of_device.h>
#include <linux/of_net.h>
#include <linux/of_mdio.h>
#include <linux/clk.h>
@@ -183,12 +184,19 @@
#define DESC_DATA_LEN_OFF 16
#define DESC_BUFF_LEN_OFF 0
#define DESC_DATA_MASK 0x7ff
+#define DESC_SG BIT(30)
+#define DESC_FRAGS_NUM_OFF 11

/* DMA descriptor ring helpers */
#define dma_ring_incr(n, s) (((n) + 1) & ((s) - 1))
#define dma_cnt(n) ((n) >> 5)
#define dma_byte(n) ((n) << 5)

+#define HW_CAP_TSO BIT(0)
+#define GEMAC_V1 0
+#define GEMAC_V2 (GEMAC_V1 | HW_CAP_TSO)
+#define HAS_CAP_TSO(hw_cap) ((hw_cap) & HW_CAP_TSO)
+
struct hix5hd2_desc {
__le32 buff_addr;
__le32 cmd;
@@ -201,6 +209,27 @@ struct hix5hd2_desc_sw {
unsigned int size;
};

+struct hix5hd2_sg_desc_ring {
+ struct sg_desc *desc;
+ dma_addr_t phys_addr;
+};
+
+struct frags_info {
+ __le32 addr;
+ __le32 size;
+};
+
+/* hardware supported max skb frags num */
+#define SG_MAX_SKB_FRAGS 17
+struct sg_desc {
+ __le32 total_len;
+ __le32 resvd0;
+ __le32 linear_addr;
+ __le32 linear_len;
+ /* reserve one more frags for memory alignment */
+ struct frags_info frags[SG_MAX_SKB_FRAGS + 1];
+};
+
#define QUEUE_NUMS 4
struct hix5hd2_priv {
struct hix5hd2_desc_sw pool[QUEUE_NUMS];
@@ -208,6 +237,7 @@ struct hix5hd2_priv {
#define rx_bq pool[1]
#define tx_bq pool[2]
#define tx_rq pool[3]
+ struct hix5hd2_sg_desc_ring tx_ring;

void __iomem *base;
void __iomem *ctrl_base;
@@ -221,6 +251,7 @@ struct hix5hd2_priv {
struct device_node *phy_node;
phy_interface_t phy_mode;

+ unsigned long hw_cap;
unsigned int speed;
unsigned int duplex;

@@ -511,6 +542,27 @@ next:
return num;
}

+static void hix5hd2_clean_sg_desc(struct hix5hd2_priv *priv,
+ struct sk_buff *skb, u32 pos)
+{
+ struct sg_desc *desc;
+ dma_addr_t addr;
+ u32 len;
+ int i;
+
+ desc = priv->tx_ring.desc + pos;
+
+ addr = le32_to_cpu(desc->linear_addr);
+ len = le32_to_cpu(desc->linear_len);
+ dma_unmap_single(priv->dev, addr, len, DMA_TO_DEVICE);
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ addr = le32_to_cpu(desc->frags[i].addr);
+ len = le32_to_cpu(desc->frags[i].size);
+ dma_unmap_page(priv->dev, addr, len, DMA_TO_DEVICE);
+ }
+}
+
static void hix5hd2_xmit_reclaim(struct net_device *dev)
{
struct sk_buff *skb;
@@ -538,8 +590,15 @@ static void hix5hd2_xmit_reclaim(struct net_device *dev)
pkts_compl++;
bytes_compl += skb->len;
desc = priv->tx_rq.desc + pos;
- addr = le32_to_cpu(desc->buff_addr);
- dma_unmap_single(priv->dev, addr, skb->len, DMA_TO_DEVICE);
+
+ if (skb_shinfo(skb)->nr_frags) {
+ hix5hd2_clean_sg_desc(priv, skb, pos);
+ } else {
+ addr = le32_to_cpu(desc->buff_addr);
+ dma_unmap_single(priv->dev, addr, skb->len,
+ DMA_TO_DEVICE);
+ }
+
priv->tx_skb[pos] = NULL;
dev_consume_skb_any(skb);
pos = dma_ring_incr(pos, TX_DESC_NUM);
@@ -600,12 +659,66 @@ static irqreturn_t hix5hd2_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}

+static u32 hix5hd2_get_desc_cmd(struct sk_buff *skb, unsigned long hw_cap)
+{
+ u32 cmd = 0;
+
+ if (HAS_CAP_TSO(hw_cap)) {
+ if (skb_shinfo(skb)->nr_frags)
+ cmd |= DESC_SG;
+ cmd |= skb_shinfo(skb)->nr_frags << DESC_FRAGS_NUM_OFF;
+ } else {
+ cmd |= DESC_FL_FULL |
+ ((skb->len & DESC_DATA_MASK) << DESC_BUFF_LEN_OFF);
+ }
+
+ cmd |= (skb->len & DESC_DATA_MASK) << DESC_DATA_LEN_OFF;
+ cmd |= DESC_VLD_BUSY;
+
+ return cmd;
+}
+
+static int hix5hd2_fill_sg_desc(struct hix5hd2_priv *priv,
+ struct sk_buff *skb, u32 pos)
+{
+ struct sg_desc *desc;
+ dma_addr_t addr;
+ int ret;
+ int i;
+
+ desc = priv->tx_ring.desc + pos;
+
+ desc->total_len = cpu_to_le32(skb->len);
+ addr = dma_map_single(priv->dev, skb->data, skb_headlen(skb),
+ DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(priv->dev, addr)))
+ return -EINVAL;
+ desc->linear_addr = cpu_to_le32(addr);
+ desc->linear_len = cpu_to_le32(skb_headlen(skb));
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+ skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+ int len = frag->size;
+
+ addr = skb_frag_dma_map(priv->dev, frag, 0, len, DMA_TO_DEVICE);
+ ret = dma_mapping_error(priv->dev, addr);
+ if (unlikely(ret))
+ return -EINVAL;
+ desc->frags[i].addr = cpu_to_le32(addr);
+ desc->frags[i].size = cpu_to_le32(len);
+ }
+
+ return 0;
+}
+
static int hix5hd2_net_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct hix5hd2_priv *priv = netdev_priv(dev);
struct hix5hd2_desc *desc;
dma_addr_t addr;
u32 pos;
+ u32 cmd;
+ int ret;

/* software write pointer */
pos = dma_cnt(readl_relaxed(priv->base + TX_BQ_WR_ADDR));
@@ -616,18 +729,31 @@ static int hix5hd2_net_xmit(struct sk_buff *skb, struct net_device *dev)
return NETDEV_TX_BUSY;
}

- addr = dma_map_single(priv->dev, skb->data, skb->len, DMA_TO_DEVICE);
- if (dma_mapping_error(priv->dev, addr)) {
- dev_kfree_skb_any(skb);
- return NETDEV_TX_OK;
- }
-
desc = priv->tx_bq.desc + pos;
+
+ cmd = hix5hd2_get_desc_cmd(skb, priv->hw_cap);
+ desc->cmd = cpu_to_le32(cmd);
+
+ if (skb_shinfo(skb)->nr_frags) {
+ ret = hix5hd2_fill_sg_desc(priv, skb, pos);
+ if (unlikely(ret)) {
+ dev_kfree_skb_any(skb);
+ dev->stats.tx_dropped++;
+ return NETDEV_TX_OK;
+ }
+ addr = priv->tx_ring.phys_addr + pos * sizeof(struct sg_desc);
+ } else {
+ addr = dma_map_single(priv->dev, skb->data, skb->len,
+ DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(priv->dev, addr))) {
+ dev_kfree_skb_any(skb);
+ dev->stats.tx_dropped++;
+ return NETDEV_TX_OK;
+ }
+ }
desc->buff_addr = cpu_to_le32(addr);
+
priv->tx_skb[pos] = skb;
- desc->cmd = cpu_to_le32(DESC_VLD_BUSY | DESC_FL_FULL |
- (skb->len & DESC_DATA_MASK) << DESC_DATA_LEN_OFF |
- (skb->len & DESC_DATA_MASK) << DESC_BUFF_LEN_OFF);

/* ensure desc updated */
wmb();
@@ -862,10 +988,40 @@ error_free_pool:
return -ENOMEM;
}

+static int hix5hd2_init_sg_desc_queue(struct hix5hd2_priv *priv)
+{
+ struct sg_desc *desc;
+ dma_addr_t phys_addr;
+
+ desc = (struct sg_desc *)dma_alloc_coherent(priv->dev,
+ TX_DESC_NUM * sizeof(struct sg_desc),
+ &phys_addr, GFP_KERNEL);
+ if (!desc)
+ return -ENOMEM;
+
+ priv->tx_ring.desc = desc;
+ priv->tx_ring.phys_addr = phys_addr;
+
+ return 0;
+}
+
+static void hix5hd2_destroy_sg_desc_queue(struct hix5hd2_priv *priv)
+{
+ if (priv->tx_ring.desc) {
+ dma_free_coherent(priv->dev,
+ TX_DESC_NUM * sizeof(struct sg_desc),
+ priv->tx_ring.desc, priv->tx_ring.phys_addr);
+ priv->tx_ring.desc = NULL;
+ }
+}
+
+static const struct of_device_id hix5hd2_of_match[];
+
static int hix5hd2_dev_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
+ const struct of_device_id *of_id = NULL;
struct net_device *ndev;
struct hix5hd2_priv *priv;
struct resource *res;
@@ -883,6 +1039,13 @@ static int hix5hd2_dev_probe(struct platform_device *pdev)
priv->dev = dev;
priv->netdev = ndev;

+ of_id = of_match_device(hix5hd2_of_match, dev);
+ if (!of_id) {
+ ret = -EINVAL;
+ goto out_free_netdev;
+ }
+ priv->hw_cap = (unsigned long)of_id->data;
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->base = devm_ioremap_resource(dev, res);
if (IS_ERR(priv->base)) {
@@ -972,11 +1135,24 @@ static int hix5hd2_dev_probe(struct platform_device *pdev)
ndev->ethtool_ops = &hix5hd2_ethtools_ops;
SET_NETDEV_DEV(ndev, dev);

+ if (HAS_CAP_TSO(priv->hw_cap))
+ ndev->hw_features |= NETIF_F_SG;
+
+ ndev->features |= ndev->hw_features | NETIF_F_HIGHDMA;
+ ndev->vlan_features |= ndev->features;
+
ret = hix5hd2_init_hw_desc_queue(priv);
if (ret)
goto out_phy_node;

netif_napi_add(ndev, &priv->napi, hix5hd2_poll, NAPI_POLL_WEIGHT);
+
+ if (HAS_CAP_TSO(priv->hw_cap)) {
+ ret = hix5hd2_init_sg_desc_queue(priv);
+ if (ret)
+ goto out_destroy_queue;
+ }
+
ret = register_netdev(priv->netdev);
if (ret) {
netdev_err(ndev, "register_netdev failed!");
@@ -988,6 +1164,8 @@ static int hix5hd2_dev_probe(struct platform_device *pdev)
return ret;

out_destroy_queue:
+ if (HAS_CAP_TSO(priv->hw_cap))
+ hix5hd2_destroy_sg_desc_queue(priv);
netif_napi_del(&priv->napi);
hix5hd2_destroy_hw_desc_queue(priv);
out_phy_node:
@@ -1012,6 +1190,8 @@ static int hix5hd2_dev_remove(struct platform_device *pdev)
mdiobus_unregister(priv->bus);
mdiobus_free(priv->bus);

+ if (HAS_CAP_TSO(priv->hw_cap))
+ hix5hd2_destroy_sg_desc_queue(priv);
hix5hd2_destroy_hw_desc_queue(priv);
of_node_put(priv->phy_node);
cancel_work_sync(&priv->tx_timeout_task);
@@ -1021,7 +1201,10 @@ static int hix5hd2_dev_remove(struct platform_device *pdev)
}

static const struct of_device_id hix5hd2_of_match[] = {
- {.compatible = "hisilicon,hix5hd2-gmac",},
+ { .compatible = "hisilicon,hisi-gemac-v1", .data = (void *)GEMAC_V1 },
+ { .compatible = "hisilicon,hisi-gemac-v2", .data = (void *)GEMAC_V2 },
+ { .compatible = "hisilicon,hix5hd2-gemac", .data = (void *)GEMAC_V1 },
+ { .compatible = "hisilicon,hi3798cv200-gemac", .data = (void *)GEMAC_V2 },
{},
};

@@ -1029,7 +1212,7 @@ MODULE_DEVICE_TABLE(of, hix5hd2_of_match);

static struct platform_driver hix5hd2_dev_driver = {
.driver = {
- .name = "hix5hd2-gmac",
+ .name = "hisi-gemac",
.of_match_table = hix5hd2_of_match,
},
.probe = hix5hd2_dev_probe,
@@ -1038,6 +1221,6 @@ static struct platform_driver hix5hd2_dev_driver = {

module_platform_driver(hix5hd2_dev_driver);

-MODULE_DESCRIPTION("HISILICON HIX5HD2 Ethernet driver");
+MODULE_DESCRIPTION("HISILICON Gigabit Ethernet MAC driver");
MODULE_LICENSE("GPL v2");
-MODULE_ALIAS("platform:hix5hd2-gmac");
+MODULE_ALIAS("platform:hisi-gemac");
--
2.8.2