Re: [PATCH v2 1/5] ethernet: add sun8i-emac driver
From: Maxime Ripard
Date: Mon Jul 25 2016 - 15:55:09 EST
On Wed, Jul 20, 2016 at 10:03:16AM +0200, LABBE Corentin wrote:
> This patch add support for sun8i-emac ethernet MAC hardware.
> It could be found in Allwinner H3/A83T/A64 SoCs.
>
> It supports 10/100/1000 Mbit/s speed with half/full duplex.
> It can use an internal PHY (MII 10/100) or an external PHY
> via RGMII/RMII.
>
> Signed-off-by: LABBE Corentin <clabbe.montjoie@xxxxxxxxx>
> ---
> drivers/net/ethernet/allwinner/Kconfig | 13 +
> drivers/net/ethernet/allwinner/Makefile | 1 +
> drivers/net/ethernet/allwinner/sun8i-emac.c | 2129 +++++++++++++++++++++++++++
> 3 files changed, 2143 insertions(+)
> create mode 100644 drivers/net/ethernet/allwinner/sun8i-emac.c
>
> diff --git a/drivers/net/ethernet/allwinner/Kconfig b/drivers/net/ethernet/allwinner/Kconfig
> index 47da7e7..060569c 100644
> --- a/drivers/net/ethernet/allwinner/Kconfig
> +++ b/drivers/net/ethernet/allwinner/Kconfig
> @@ -33,4 +33,17 @@ config SUN4I_EMAC
> To compile this driver as a module, choose M here. The module
> will be called sun4i-emac.
>
> +config SUN8I_EMAC
> + tristate "Allwinner sun8i EMAC support"
> + depends on ARCH_SUNXI || COMPILE_TEST
> + depends on OF
> + select MII
> + select PHYLIB
> + ---help---
> + This driver support the sun8i EMAC ethernet driver present on
> + H3/A83T/A64 Allwinner SoCs.
> +
> + To compile this driver as a module, choose M here. The module
> + will be called sun8i-emac.
> +
> endif # NET_VENDOR_ALLWINNER
> diff --git a/drivers/net/ethernet/allwinner/Makefile b/drivers/net/ethernet/allwinner/Makefile
> index 03129f7..8bd1693c 100644
> --- a/drivers/net/ethernet/allwinner/Makefile
> +++ b/drivers/net/ethernet/allwinner/Makefile
> @@ -3,3 +3,4 @@
> #
>
> obj-$(CONFIG_SUN4I_EMAC) += sun4i-emac.o
> +obj-$(CONFIG_SUN8I_EMAC) += sun8i-emac.o
> diff --git a/drivers/net/ethernet/allwinner/sun8i-emac.c b/drivers/net/ethernet/allwinner/sun8i-emac.c
> new file mode 100644
> index 0000000..fc0c1dd
> --- /dev/null
> +++ b/drivers/net/ethernet/allwinner/sun8i-emac.c
> @@ -0,0 +1,2129 @@
> +/*
> + * sun8i-emac driver
> + *
> + * Copyright (C) 2015-2016 Corentin LABBE <clabbe.montjoie@xxxxxxxxx>
> + *
> + * This is the driver for Allwinner Ethernet MAC found in H3/A83T/A64 SoC
> + *
> + * TODO:
> + * - MAC filtering
> + * - Jumbo frame
> + * - features rx-all (NETIF_F_RXALL_BIT)
> + */
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/etherdevice.h>
> +#include <linux/interrupt.h>
> +#include <linux/iopoll.h>
> +#include <linux/mii.h>
> +#include <linux/module.h>
> +#include <linux/netdevice.h>
> +#include <linux/of_device.h>
> +#include <linux/of_mdio.h>
> +#include <linux/of_net.h>
> +#include <linux/phy.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/pinctrl/pinctrl.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset.h>
> +#include <linux/scatterlist.h>
> +#include <linux/skbuff.h>
> +
> +#define SUN8I_EMAC_BASIC_CTL0 0x00
> +#define SUN8I_EMAC_BASIC_CTL1 0x04
> +#define SUN8I_EMAC_INT_STA 0x08
> +#define SUN8I_EMAC_INT_EN 0x0C
> +#define SUN8I_EMAC_TX_CTL0 0x10
> +#define SUN8I_EMAC_TX_CTL1 0x14
> +#define SUN8I_EMAC_TX_FLOW_CTL 0x1C
> +#define SUN8I_EMAC_RX_CTL0 0x24
> +#define SUN8I_EMAC_RX_CTL1 0x28
> +#define SUN8I_EMAC_RX_FRM_FLT 0x38
> +#define SUN8I_EMAC_MDIO_CMD 0x48
> +#define SUN8I_EMAC_MDIO_DATA 0x4C
> +#define SUN8I_EMAC_TX_DMA_STA 0xB0
> +#define SUN8I_EMAC_TX_CUR_DESC 0xB4
> +#define SUN8I_EMAC_TX_CUR_BUF 0xB8
> +#define SUN8I_EMAC_RX_DMA_STA 0xC0
> +
> +#define MDIO_CMD_MII_BUSY BIT(0)
> +#define MDIO_CMD_MII_WRITE BIT(1)
> +#define MDIO_CMD_MII_PHY_REG_ADDR_MASK GENMASK(8, 4)
> +#define MDIO_CMD_MII_PHY_REG_ADDR_SHIFT 4
> +#define MDIO_CMD_MII_PHY_ADDR_MASK GENMASK(16, 12)
> +#define MDIO_CMD_MII_PHY_ADDR_SHIFT 12
> +
> +#define SUN8I_EMAC_MACADDR_HI 0x50
> +#define SUN8I_EMAC_MACADDR_LO 0x54
> +
> +#define SUN8I_EMAC_RX_DESC_LIST 0x34
> +#define SUN8I_EMAC_TX_DESC_LIST 0x20
> +
> +#define SUN8I_EMAC_RX_DO_CRC BIT(27)
> +#define SUN8I_EMAC_RX_STRIP_FCS BIT(28)
> +
> +#define SUN8I_COULD_BE_USED_BY_DMA BIT(31)
> +
> +/* Used in RX_CTL1*/
> +#define RX_DMA_EN BIT(30)
> +#define RX_DMA_START BIT(31)
> +/* Used in TX_CTL1*/
> +#define TX_DMA_EN BIT(30)
> +#define TX_DMA_START BIT(31)
> +
> +/* Used in RX_CTL0 */
> +#define RX_RECEIVER_EN BIT(31)
> +/* Used in TX_CTL0 */
> +#define TX_TRANSMITTER_EN BIT(31)
> +
> +/* Basic CTL0 */
> +#define BCTL0_FD BIT(0)
> +#define BCTL0_SPEED_10 2
> +#define BCTL0_SPEED_100 3
> +#define BCTL0_SPEED_MASK GENMASK(3, 2)
> +#define BCTL0_SPEED_SHIFT 2
> +
> +#define FLOW_RX 1
> +#define FLOW_TX 2
> +
> +#define RX_INT BIT(8)
> +#define TX_INT BIT(0)
> +
> +/* Bits used in frame RX status */
> +#define DSC_RX_FIRST BIT(9)
> +#define DSC_RX_LAST BIT(8)
> +
> +/* Bits used in frame TX ctl */
> +#define SUN8I_EMAC_MAGIC_TX_BIT BIT(24)
> +#define SUN8I_EMAC_TX_DO_CRC (BIT(27) | BIT(28))
> +#define DSC_TX_FIRST BIT(29)
> +#define DSC_TX_LAST BIT(30)
> +#define SUN8I_EMAC_WANT_INT BIT(31)
Some defines are prefixed, some aren't, please be consistent (and I'd
prefer the former).
> +
> +enum emac_variant {
> + NONE_EMAC,/* for be sure that variant is non-0 if set */
> + A83T_EMAC,
> + H3_EMAC,
> + A64_EMAC,
> +};
Please don't use an enum, but attach a private structure with whatever
information you need there.
> +static const char const estats_str[][ETH_GSTRING_LEN] = {
> + /* errors */
> + "rx_payload_error",
> + "rx_CRC_error",
> + "rx_phy_error",
> + "rx_length_error",
> + "rx_col_error",
> + "rx_header_error",
> + "rx_overflow_error",
> + "rx_saf_error",
> + "rx_daf_error",
> + "rx_buf_error",
> + /* misc infos */
> + "tx_stop_queue",
> + "rx_dma_ua",
> + "rx_dma_stop",
> + "tx_dma_ua",
> + "tx_dma_stop",
> + "rx_hw_csum",
> + "tx_hw_csum",
> + /* interrupts */
> + "rx_int",
> + "tx_int",
> + "rx_early_int",
> + "tx_early_int",
> + "tx_underflow_int",
> + /* debug */
> + "tx_used_desc",
> + "napi_schedule",
> + "napi_underflow",
> +};
> +
> +struct sun8i_emac_stats {
> + u64 rx_payload_error;
> + u64 rx_crc_error;
> + u64 rx_phy_error;
> + u64 rx_length_error;
> + u64 rx_col_error;
> + u64 rx_header_error;
> + u64 rx_overflow_error;
> + u64 rx_saf_fail;
> + u64 rx_daf_fail;
> + u64 rx_buf_error;
> +
> + u64 tx_stop_queue;
> + u64 rx_dma_ua;
> + u64 rx_dma_stop;
> + u64 tx_dma_ua;
> + u64 tx_dma_stop;
> + u64 rx_hw_csum;
> + u64 tx_hw_csum;
> +
> + u64 rx_int;
> + u64 tx_int;
> + u64 rx_early_int;
> + u64 tx_early_int;
> + u64 tx_underflow_int;
> +
> + u64 tx_used_desc;
> + u64 napi_schedule;
> + u64 napi_underflow;
> +};
> +
> +/* The datasheet said that each descriptor can transfers up to 4096bytes
> + * But latter, a register documentation reduce that value to 2048
> + * Anyway using 2048 cause strange behaviours and even BSP driver use 2047
> + */
> +#define DESC_BUF_MAX 2044
> +#if (DESC_BUF_MAX < (ETH_FRAME_LEN + 4))
> +#error "DESC_BUF_MAX must be set at minimum to ETH_FRAME_LEN + 4"
> +#endif
Why would we need to change that?
> +/* MAGIC value for knowing if a descriptor is available or not */
> +#define DCLEAN (BIT(16) | BIT(14) | BIT(12) | BIT(10) | BIT(9))
> +
> +/* struct dma_desc - Structure of DMA descriptor used by the hardware
> + * @status: Status of the frame written by HW, so RO for the
> + * driver (except for BIT(31) which is R/W)
> + * @ctl: Information on the frame written by the driver (INT, len,...)
> + * @buf_addr: physical address of the frame data
> + * @next: physical address of next dma_desc
> + */
> +struct dma_desc {
> + u32 status;
> + u32 ctl;
> + u32 buf_addr;
> + u32 next;
> +};
You should use the endian-aware variants here.
> +/* Describe how data from skb are DMA mapped (used in txinfo map member) */
> +#define MAP_SINGLE 1
> +#define MAP_PAGE 2
> +
> +/* Structure for storing information about data in TX ring buffer */
> +struct txinfo {
> + struct sk_buff *skb;
> + int map;
> +};
> +
> +struct sun8i_emac_priv {
> + void __iomem *base;
> + void __iomem *syscon;
> + int irq;
> + struct device *dev;
> + struct net_device *ndev;
> + struct mii_bus *mdio;
> + struct napi_struct napi;
> + spinlock_t tx_lock;/* control the access of transmit descriptors */
> + int duplex;
> + int speed;
> + int link;
> + int phy_interface;
> + enum emac_variant variant;
> + struct device_node *phy_node;
> + struct clk *ahb_clk;
> + struct clk *ephy_clk;
> + bool use_internal_phy;
> +
> + struct reset_control *rst;
> + struct reset_control *rst_ephy;
> +
> + struct dma_desc *dd_rx;
> + dma_addr_t dd_rx_phy;
> + struct dma_desc *dd_tx;
> + dma_addr_t dd_tx_phy;
> + struct sk_buff **rx_skb;
> + struct txinfo *txl;
> +
> + int nbdesc_tx;
> + int nbdesc_rx;
> + int tx_slot;
> + int tx_dirty;
> + int rx_dirty;
> + struct sun8i_emac_stats estats;
> + u32 msg_enable;
> + int flow_ctrl;
> + int pause;
> +};
> +
> +static irqreturn_t sun8i_emac_dma_interrupt(int irq, void *dev_id);
> +
> +static void rb_inc(int *p, const int max)
> +{
> + (*p)++;
> + (*p) %= max;
No locking?
> +}
> +
> +/* Return the number of contiguous free descriptors
> + * starting from tx_slot
> + */
> +static int rb_tx_numfreedesc(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + if (priv->tx_slot < priv->tx_dirty)
> + return priv->tx_dirty - priv->tx_slot;
> +
> + return (priv->nbdesc_tx - priv->tx_slot) + priv->tx_dirty;
> +}
> +
> +/* Allocate a skb in a DMA descriptor
> + *
> + * @i index of slot to fill
> +*/
> +static int sun8i_emac_rx_skb(struct net_device *ndev, int i)
You're missing the first parameters in your comment.
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct dma_desc *ddesc;
> + struct sk_buff *skb;
> +
> + ddesc = priv->dd_rx + i;
> +
> + ddesc->ctl = 0;
> +
> + skb = netdev_alloc_skb_ip_align(ndev, DESC_BUF_MAX);
> + if (!skb)
> + return -ENOMEM;
> +
> + /* should not happen */
> + if (unlikely(priv->rx_skb[i]))
> + dev_warn(priv->dev, "BUG: Leaking a skbuff\n");
> +
> + priv->rx_skb[i] = skb;
> +
> + ddesc->buf_addr = dma_map_single(priv->dev, skb->data,
> + DESC_BUF_MAX, DMA_FROM_DEVICE);
> + if (dma_mapping_error(priv->dev, ddesc->buf_addr)) {
> + dev_err(priv->dev, "ERROR: Cannot map RX buffer for DMA\n");
> + dev_kfree_skb(skb);
> + return -EFAULT;
> + }
> + ddesc->ctl |= DESC_BUF_MAX;
> + wmb();/* SUN8I_COULD_BE_USED_BY_DMA must be the last value written */
Please don't put a comment on the line itself, but above.
> + ddesc->status = SUN8I_COULD_BE_USED_BY_DMA;
> +
> + return 0;
> +}
> +
> +static void sun8i_emac_stop_tx(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v;
> +
> + netif_stop_queue(ndev);
> +
> + v = readl(priv->base + SUN8I_EMAC_TX_CTL0);
> + v &= ~TX_TRANSMITTER_EN;/*Disable transmitter after current reception*/
Ditto. And put some spaces between /* and the text (and */)
> + writel(v, priv->base + SUN8I_EMAC_TX_CTL0);
A new line here.
> + v = readl(priv->base + SUN8I_EMAC_TX_CTL1);
> + v &= ~TX_DMA_EN; /* Stop TX DMA */
> + writel(v, priv->base + SUN8I_EMAC_TX_CTL1);
> +}
> +
> +static void sun8i_emac_stop_rx(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v;
> +
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL0);
> + v &= ~RX_RECEIVER_EN; /* Disable receiver after current reception */
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL0);
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL1);
> + v &= ~RX_DMA_EN; /* Stop RX DMA */
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL1);
Same comments.
> +}
> +
> +static void sun8i_emac_start_rx(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v;
> +
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL0);
> + v |= RX_RECEIVER_EN;/* Enable receiver */
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL0);
> +
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL1);
> + v |= RX_DMA_START;
> + v |= RX_DMA_EN;
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL1);
> +}
> +
> +static void sun8i_emac_start_tx(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v;
> +
> + v = readl(priv->base + SUN8I_EMAC_TX_CTL0);
> + v |= TX_TRANSMITTER_EN;
> + writel(v, priv->base + SUN8I_EMAC_TX_CTL0);
> +
> + v = readl(priv->base + SUN8I_EMAC_TX_CTL1);
> + v |= TX_DMA_START;
> + v |= TX_DMA_EN;
> + writel(v, priv->base + SUN8I_EMAC_TX_CTL1);
> +}
> +
> +/* Set MAC address for slot index
> + * @addr: the MAC address to set
> + * @index: The index of slot where to set address.
> + * The slot 0 is the main MACaddr
> + */
It looks like you have function comments in something that looks like
kerneldoc, but is not. And then you have comments that are not
following that at all. Please be consistent.
> +static void sun8i_emac_set_macaddr(struct sun8i_emac_priv *priv,
> + const u8 *addr, int index)
> +{
> + u32 v;
> +
> + dev_info(priv->dev, "device MAC address slot %d %02x:%02x:%02x:%02x:%02x:%02x\n",
> + index, addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
The logging level is probably too high here, and you already have the
%pM format to print MAC addresses.
> +
> + v = (addr[5] << 8) | addr[4];
> + writel(v, priv->base + SUN8I_EMAC_MACADDR_HI + index * 8);
New line.
> + v = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
> + writel(v, priv->base + SUN8I_EMAC_MACADDR_LO + index * 8);
> +}
> +
> +static void sun8i_emac_set_link_mode(struct sun8i_emac_priv *priv)
> +{
> + u32 v;
> +
> + v = readl(priv->base + SUN8I_EMAC_BASIC_CTL0);
> +
> + if (priv->duplex)
> + v |= BCTL0_FD;
> + else
> + v &= ~BCTL0_FD;
> +
> + v &= ~BCTL0_SPEED_MASK;
New line.
> + switch (priv->speed) {
> + case 1000:
> + break;
> + case 100:
> + v |= BCTL0_SPEED_100 << BCTL0_SPEED_SHIFT;
> + break;
> + case 10:
> + v |= BCTL0_SPEED_10 << BCTL0_SPEED_SHIFT;
> + break;
> + }
No default?
> + writel(v, priv->base + SUN8I_EMAC_BASIC_CTL0);
> +}
> +
> +static void sun8i_emac_flow_ctrl(struct sun8i_emac_priv *priv, int duplex,
> + int fc)
> +{
> + u32 flow = 0;
> +
> + netif_dbg(priv, link, priv->ndev, "%s %d %d\n", __func__,
> + duplex, fc);
> +
> + flow = readl(priv->base + SUN8I_EMAC_RX_CTL0);
> + if (fc & FLOW_RX)
> + flow |= BIT(16);
> + else
> + flow &= ~BIT(16);
> + writel(flow, priv->base + SUN8I_EMAC_RX_CTL0);
> +
> + flow = readl(priv->base + SUN8I_EMAC_TX_FLOW_CTL);
> + if (fc & FLOW_TX)
> + flow |= BIT(0);
> + else
> + flow &= ~BIT(0);
> + writel(flow, priv->base + SUN8I_EMAC_TX_FLOW_CTL);
> +}
> +
> +/* Grab a frame into a skb from descriptor number i */
> +static int sun8i_emac_rx_from_ddesc(struct net_device *ndev, int i)
> +{
> + struct sk_buff *skb;
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct dma_desc *ddesc = priv->dd_rx + i;
> + int frame_len;
> + int rxcsum_done = 0;
> +
> + if (ndev->features & NETIF_F_RXCSUM)
> + rxcsum_done = 1;
> +
> + /* bit0/bit7 work only on IPv4/IPv6 TCP traffic,
> + * (not on ARP for example) so we dont raise rx_errors/discard frame
> + */
> + /* the checksum or length of received frame's payload is wrong*/
> + if (ddesc->status & BIT(0)) {
> + priv->estats.rx_payload_error++;
> + rxcsum_done = 0;
> + }
New line
> + /* RX_CRC_ERR */
> + if (ddesc->status & BIT(1)) {
> + priv->ndev->stats.rx_errors++;
> + priv->ndev->stats.rx_crc_errors++;
> + priv->estats.rx_crc_error++;
> + goto discard_frame;
> + }
Ditto
> + /* RX_PHY_ERR */
> + if ((ddesc->status & BIT(3))) {
> + priv->ndev->stats.rx_errors++;
> + priv->estats.rx_phy_error++;
> + goto discard_frame;
> + }
Ditto
> + /* RX_LENGTH_ERR */
> + if ((ddesc->status & BIT(4))) {
> + priv->ndev->stats.rx_errors++;
> + priv->ndev->stats.rx_length_errors++;
> + priv->estats.rx_length_error++;
> + goto discard_frame;
> + }
... You get the idea.
> + /* RX_COL_ERR */
> + if ((ddesc->status & BIT(6))) {
> + priv->ndev->stats.rx_errors++;
> + priv->estats.rx_col_error++;
> + goto discard_frame;
> + }
> + /* RX_HEADER_ERR */
> + if ((ddesc->status & BIT(7))) {
> + priv->estats.rx_header_error++;
> + rxcsum_done = 0;
> + }
> + /* RX_OVERFLOW_ERR */
> + if ((ddesc->status & BIT(11))) {
> + priv->ndev->stats.rx_over_errors++;
> + priv->estats.rx_overflow_error++;
> + goto discard_frame;
> + }
> + /* RX_NO_ENOUGTH_BUF_ERR */
> + if ((ddesc->status & BIT(14))) {
> + priv->ndev->stats.rx_errors++;
> + priv->estats.rx_buf_error++;
> + goto discard_frame;
> + }
> +
> + /* BIT(9) is for the first frame, not having it is bad since we do not
> + * handle Jumbo frame
> + */
> + if ((ddesc->status & DSC_RX_FIRST) == 0) {
> + dev_warn_ratelimited(priv->dev, "BUG: Non-first frame received. This should not happen\n");
Either you use a BUG macro, or you don't, but faking it doesn't really
seem appropriate (and please try to stay below the 80 chars limit).
> + goto discard_frame;
> + }
> + frame_len = (ddesc->status >> 16) & 0x3FFF;
> + if (!(ndev->features & NETIF_F_RXFCS))
> + frame_len -= ETH_FCS_LEN;
> +
> + skb = priv->rx_skb[i];
> +
> + netif_dbg(priv, rx_status, priv->ndev,
> + "%s from %02d %pad len=%d status=%x st=%x\n",
> + __func__, i, &ddesc, frame_len, ddesc->status, ddesc->ctl);
> +
> + skb_put(skb, frame_len);
> +
> + dma_unmap_single(priv->dev, ddesc->buf_addr, DESC_BUF_MAX,
> + DMA_FROM_DEVICE);
> + skb->protocol = eth_type_trans(skb, priv->ndev);
> + if (rxcsum_done) {
> + skb->ip_summed = CHECKSUM_UNNECESSARY;
> + priv->estats.rx_hw_csum++;
> + } else {
> + skb->ip_summed = CHECKSUM_PARTIAL;
> + }
> +
> + priv->ndev->stats.rx_packets++;
> + priv->ndev->stats.rx_bytes += frame_len;
> + priv->rx_skb[i] = NULL;
> +
> + /* this frame is not the last */
> + if ((ddesc->status & DSC_RX_LAST) == 0) {
> + dev_warn(priv->dev, "Multi frame not implemented currlen=%d\n",
> + frame_len);
> + }
> +
> + sun8i_emac_rx_skb(ndev, i);
> + napi_gro_receive(&priv->napi, skb);
> +
> + return 0;
> + /* If the frame need to be dropped, we simply reuse the buffer */
> +discard_frame:
> + ddesc->ctl = DESC_BUF_MAX;
> + wmb();/* SUN8I_COULD_BE_USED_BY_DMA must be the last value written */
> + ddesc->status = SUN8I_COULD_BE_USED_BY_DMA;
> + return 0;
> +}
> +
> +/* iterate over dma_desc for finding completed xmit.
> + * Called from interrupt context, so no need to spinlock tx
> + *
> + * The problem is: how to know that a descriptor is sent and not just in
> + * preparation.
> + * Need to have status=0 and st set but this is the state of first frame just
> + * before setting the own-by-DMA bit.
> + * The solution is to used the artificial value DCLEAN.
> + */
> +static int sun8i_emac_complete_xmit(struct net_device *ndev, int budget)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct dma_desc *ddesc;
> + int frame_len;
> + int work = 0;
> +
> + spin_lock(&priv->tx_lock);
> + do {
> + ddesc = priv->dd_tx + priv->tx_dirty;
> +
> + if (ddesc->status & SUN8I_COULD_BE_USED_BY_DMA)
> + goto xmit_end;
> +
> + if (ddesc->status == DCLEAN)
> + goto xmit_end;
> +
> + if (ddesc->status == 0 && !ddesc->ctl) {
> + dev_err(priv->dev, "BUG: reached the void %d %d\n",
> + priv->tx_dirty, priv->tx_slot);
> + goto xmit_end;
> + }
> +
> + /* TX_UNDERFLOW_ERR */
> + if (ddesc->status & BIT(1))
> + priv->ndev->stats.tx_errors++;
> + /* TX_DEFER_ERR */
> + if (ddesc->status & BIT(2))
> + priv->ndev->stats.tx_errors++;
> + /* BIT 6:3 numbers of collisions */
> + if (ddesc->status & 0x78)
> + priv->ndev->stats.collisions +=
> + (ddesc->status & 0x78) >> 3;
> + /* TX_COL_ERR_1 */
> + if (ddesc->status & BIT(8))
> + priv->ndev->stats.tx_errors++;
> + /* TX_COL_ERR_0 */
> + if (ddesc->status & BIT(9))
> + priv->ndev->stats.tx_errors++;
> + /* TX_CRS_ERR */
> + if (ddesc->status & BIT(10))
> + priv->ndev->stats.tx_carrier_errors++;
> + /* TX_PAYLOAD_ERR */
> + if (ddesc->status & BIT(12))
> + priv->ndev->stats.tx_errors++;
> + /* TX_LENGTH_ERR */
> + if (ddesc->status & BIT(14))
> + priv->ndev->stats.tx_errors++;
> + /* TX_HEADER_ERR */
> + if (ddesc->status & BIT(16))
> + priv->ndev->stats.tx_errors++;
> + frame_len = ddesc->ctl & 0x3FFF;
> + if (priv->txl[priv->tx_dirty].map == MAP_SINGLE)
> + dma_unmap_single(priv->dev, ddesc->buf_addr,
> + frame_len, DMA_TO_DEVICE);
> + else
> + dma_unmap_page(priv->dev, ddesc->buf_addr,
> + frame_len, DMA_TO_DEVICE);
> + /* we can free skb only on last frame */
> + if (priv->txl[priv->tx_dirty].skb && (ddesc->ctl & DSC_TX_LAST))
> + dev_kfree_skb_irq(priv->txl[priv->tx_dirty].skb);
> +
> + priv->txl[priv->tx_dirty].skb = NULL;
> + priv->txl[priv->tx_dirty].map = 0;
> + ddesc->ctl = 0;
> + wmb(); /* setting to DCLEAN is the last value to be set */
> + ddesc->status = DCLEAN;
> + work++;
> +
> + rb_inc(&priv->tx_dirty, priv->nbdesc_tx);
> + ddesc = priv->dd_tx + priv->tx_dirty;
> + } while (ddesc->ctl && !(ddesc->status & SUN8I_COULD_BE_USED_BY_DMA));
> +
> + if (netif_queue_stopped(ndev) &&
> + rb_tx_numfreedesc(ndev) > MAX_SKB_FRAGS + 1)
> + netif_wake_queue(ndev);
> +xmit_end:
> + spin_unlock(&priv->tx_lock);
> + return work;
> +}
> +
> +static int sun8i_emac_poll(struct napi_struct *napi, int budget)
> +{
> + struct sun8i_emac_priv *priv =
> + container_of(napi, struct sun8i_emac_priv, napi);
> + struct net_device *ndev = priv->ndev;
> + int worked;
> + struct dma_desc *ddesc;
> +
> + priv->estats.napi_schedule++;
> + worked = sun8i_emac_complete_xmit(ndev, budget);
> +
> + ddesc = priv->dd_rx + priv->rx_dirty;
> + while (!(ddesc->status & SUN8I_COULD_BE_USED_BY_DMA) &&
> + worked < budget) {
> + sun8i_emac_rx_from_ddesc(ndev, priv->rx_dirty);
> + worked++;
> + rb_inc(&priv->rx_dirty, priv->nbdesc_rx);
> + ddesc = priv->dd_rx + priv->rx_dirty;
> + };
> + if (worked < budget) {
> + priv->estats.napi_underflow++;
> + napi_complete(&priv->napi);
> + writel(RX_INT | TX_INT, priv->base + SUN8I_EMAC_INT_EN);
> + }
> + return worked;
> +}
> +
> +static int sun8i_mdio_read(struct mii_bus *bus, int phy_addr, int phy_reg)
> +{
> + struct net_device *ndev = bus->priv;
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int err;
> + u32 reg;
> +
> + err = readl_poll_timeout(priv->base + SUN8I_EMAC_MDIO_CMD, reg,
> + !(reg & MDIO_CMD_MII_BUSY), 100, 10000);
> + if (err) {
> + dev_err(priv->dev, "%s timeout %x\n", __func__, reg);
> + return err;
> + }
> +
> + reg &= ~MDIO_CMD_MII_WRITE;
> + reg &= ~MDIO_CMD_MII_PHY_REG_ADDR_MASK;
> + reg |= (phy_reg << MDIO_CMD_MII_PHY_REG_ADDR_SHIFT) &
> + MDIO_CMD_MII_PHY_REG_ADDR_MASK;
> +
> + reg &= ~MDIO_CMD_MII_PHY_ADDR_MASK;
> +
> + reg |= (phy_addr << MDIO_CMD_MII_PHY_ADDR_SHIFT) &
> + MDIO_CMD_MII_PHY_ADDR_MASK;
> +
> + reg |= MDIO_CMD_MII_BUSY;
> +
> + writel(reg, priv->base + SUN8I_EMAC_MDIO_CMD);
> +
> + err = readl_poll_timeout(priv->base + SUN8I_EMAC_MDIO_CMD, reg,
> + !(reg & MDIO_CMD_MII_BUSY), 100, 10000);
> +
> + if (err) {
> + dev_err(priv->dev, "%s timeout %x\n", __func__, reg);
> + return err;
> + }
> +
> + return readl(priv->base + SUN8I_EMAC_MDIO_DATA);
> +}
> +
> +static int sun8i_mdio_write(struct mii_bus *bus, int phy_addr, int phy_reg,
> + u16 data)
> +{
> + struct net_device *ndev = bus->priv;
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 reg;
> + int err;
> +
> + err = readl_poll_timeout(priv->base + SUN8I_EMAC_MDIO_CMD, reg,
> + !(reg & MDIO_CMD_MII_BUSY), 100, 10000);
> + if (err) {
> + dev_err(priv->dev, "%s timeout %x\n", __func__, reg);
> + return err;
> + }
Why the poll_timeout variant?
> +
> + reg &= ~MDIO_CMD_MII_PHY_REG_ADDR_MASK;
> + reg |= (phy_reg << MDIO_CMD_MII_PHY_REG_ADDR_SHIFT) &
> + MDIO_CMD_MII_PHY_REG_ADDR_MASK;
> +
> + reg &= ~MDIO_CMD_MII_PHY_ADDR_MASK;
> + reg |= (phy_addr << MDIO_CMD_MII_PHY_ADDR_SHIFT) &
> + MDIO_CMD_MII_PHY_ADDR_MASK;
> +
> + reg |= MDIO_CMD_MII_WRITE;
> + reg |= MDIO_CMD_MII_BUSY;
> +
> + writel(reg, priv->base + SUN8I_EMAC_MDIO_CMD);
> + writel(data, priv->base + SUN8I_EMAC_MDIO_DATA);
> + dev_dbg(priv->dev, "%s %d %d %x %x\n", __func__, phy_addr, phy_reg,
> + reg, data);
Ugh. No.
> + err = readl_poll_timeout(priv->base + SUN8I_EMAC_MDIO_CMD, reg,
> + !(reg & MDIO_CMD_MII_BUSY), 100, 10000);
> + if (err) {
> + dev_err(priv->dev, "%s timeout %x\n", __func__, reg);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +static int sun8i_emac_mdio_register(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct mii_bus *bus;
> + int ret;
> +
> + bus = mdiobus_alloc();
> + if (!bus) {
> + netdev_err(ndev, "Failed to allocate a new mdio bus\n");
> + return -ENOMEM;
> + }
> +
> + bus->name = dev_name(priv->dev);
> + bus->read = &sun8i_mdio_read;
> + bus->write = &sun8i_mdio_write;
> + snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%x", bus->name, priv->dev->id);
> +
> + bus->parent = priv->dev;
> + bus->priv = ndev;
> +
> + ret = of_mdiobus_register(bus, priv->dev->of_node);
> + if (ret) {
> + netdev_err(ndev, "Could not register a MDIO bus: %d\n", ret);
> + mdiobus_free(bus);
> + return ret;
> + }
> +
> + priv->mdio = bus;
> +
> + return 0;
> +}
> +
> +static void sun8i_emac_mdio_unregister(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + mdiobus_unregister(priv->mdio);
> + mdiobus_free(priv->mdio);
> +}
> +
> +/* Run within phydev->lock */
> +static void sun8i_emac_adjust_link(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct phy_device *phydev = ndev->phydev;
> + int new_state = 0;
> +
> + netif_dbg(priv, link, priv->ndev,
> + "%s link=%x duplex=%x speed=%x\n", __func__,
> + phydev->link, phydev->duplex, phydev->speed);
> + if (!phydev)
> + return;
> +
> + if (phydev->link) {
> + if (phydev->duplex != priv->duplex) {
> + new_state = 1;
> + priv->duplex = phydev->duplex;
> + }
> + if (phydev->pause)
> + sun8i_emac_flow_ctrl(priv, phydev->duplex,
> + priv->flow_ctrl);
> +
> + if (phydev->speed != priv->speed) {
> + new_state = 1;
> + priv->speed = phydev->speed;
> + }
> +
> + if (priv->link == 0) {
> + new_state = 1;
> + priv->link = phydev->link;
> + }
> +
> + netif_dbg(priv, link, priv->ndev,
> + "%s new=%d link=%d pause=%d\n",
> + __func__, new_state, priv->link, phydev->pause);
> + if (new_state)
> + sun8i_emac_set_link_mode(priv);
> + } else if (priv->link != phydev->link) {
> + new_state = 1;
> + priv->link = 0;
> + priv->speed = 0;
> + priv->duplex = -1;
> + }
> +
> + if (new_state)
> + phy_print_status(phydev);
> +}
> +
> +/* H3 specific bits for EPHY */
> +#define H3_EPHY_ADDR_SHIFT 20
> +#define H3_EPHY_LED_POL BIT(17) /* 1: active low, 0: active high */
> +#define H3_EPHY_SHUTDOWN BIT(16) /* 1: shutdown, 0: power up */
> +#define H3_EPHY_SELECT BIT(15) /* 1: internal PHY, 0: external PHY */
> +#define H3_EPHY_DEFAULT_VALUE 0x58000
> +#define H3_EPHY_DEFAULT_MASK GENMASK(31, 15)
> +
> +/* H3/A64 specific bits */
> +#define SC_RMII_EN BIT(13) /* 1: enable RMII (overrides EPIT) */
> +
> +/* Generic system control EMAC_CLK bits */
> +#define SC_ETXDC_MASK GENMASK(2, 0)
> +#define SC_ETXDC_SHIFT 10
> +#define SC_ERXDC_MASK GENMASK(4, 0)
> +#define SC_ERXDC_SHIFT 5
> +#define SC_EPIT BIT(2) /* 1: RGMII, 0: MII */
> +#define SC_ETCS_MASK GENMASK(1, 0)
> +#define SC_ETCS_MII 0x0
> +#define SC_ETCS_EXT_GMII 0x1
> +#define SC_ETCS_INT_GMII 0x2
> +
> +static int sun8i_emac_set_syscon_ephy(struct net_device *ndev, u32 *reg)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct device_node *node = priv->dev->of_node;
> + int ret;
> +
> + *reg &= ~H3_EPHY_DEFAULT_MASK;
> + *reg |= H3_EPHY_DEFAULT_VALUE;
> +
> + if (!priv->use_internal_phy) {
> + /* switch to external PHY interface */
> + *reg &= ~H3_EPHY_SELECT;
> + return 0;
> + }
> +
> + if (priv->phy_interface != PHY_INTERFACE_MODE_MII) {
> + netdev_warn(ndev,
> + "Internal PHY requested, forcing MII mode.\n");
> + priv->phy_interface = PHY_INTERFACE_MODE_MII;
> + }
> +
> + *reg |= H3_EPHY_SELECT;
> + *reg &= ~H3_EPHY_SHUTDOWN;
> +
> + if (of_property_read_bool(node, "allwinner,leds-active-low"))
> + *reg |= H3_EPHY_LED_POL;
> +
> + ret = of_mdio_parse_addr(priv->dev, priv->phy_node);
> + if (ret < 0) {
> + netdev_err(ndev, "Could not parse MDIO addr\n");
> + return ret;
> + }
> +
> + /* of_mdio_parse_addr returns a valid (0 ~ 31) PHY
> + * address. No need to mask it again.
> + */
> + *reg |= ret << H3_EPHY_ADDR_SHIFT;
> +
> + return 0;
> +}
> +
> +static int sun8i_emac_set_syscon(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct device_node *node = priv->dev->of_node;
> + int ret;
> + u32 reg, val;
> +
> + reg = readl(priv->syscon);
> +
> + if (priv->variant == H3_EMAC) {
> + ret = sun8i_emac_set_syscon_ephy(ndev, ®);
Passing the reg variable is quite unusual, why not simply do
everything at once?
> + if (ret)
> + return ret;
> + }
> +
> + if (!of_property_read_u32(node, "allwinner,tx-delay", &val)) {
> + if (val <= SC_ETXDC_MASK) {
> + reg &= ~(SC_ETXDC_MASK << SC_ETXDC_SHIFT);
> + reg |= (val << SC_ETXDC_SHIFT);
> + } else {
> + netdev_warn(ndev, "Invalid TX clock delay: %d\n", val);
> + }
> + }
> +
> + if (!of_property_read_u32(node, "allwinner,rx-delay", &val)) {
> + if (val <= SC_ERXDC_MASK) {
> + reg &= ~(SC_ERXDC_MASK << SC_ERXDC_SHIFT);
> + reg |= (val << SC_ERXDC_SHIFT);
> + } else {
> + netdev_warn(ndev, "Invalid RX clock delay: %d\n", val);
> + }
> + }
> +
> + /* Clear interface mode bits */
> + reg &= ~(SC_ETCS_MASK | SC_EPIT);
> + if (priv->variant == H3_EMAC || priv->variant == A64_EMAC)
> + reg &= ~SC_RMII_EN;
> +
> + switch (priv->phy_interface) {
> + case PHY_INTERFACE_MODE_MII:
> + /* default */
> + break;
> + case PHY_INTERFACE_MODE_RGMII:
> + reg |= SC_EPIT | SC_ETCS_INT_GMII;
> + break;
> + case PHY_INTERFACE_MODE_RMII:
> + if (priv->variant == H3_EMAC || priv->variant == A64_EMAC) {
> + reg |= SC_RMII_EN | SC_ETCS_EXT_GMII;
> + break;
> + }
> + /* RMII not supported on A83T */
> + default:
> + netdev_err(ndev, "Unsupported interface mode: %s",
> + phy_modes(priv->phy_interface));
> + return -EINVAL;
> + }
> +
> + writel(reg, priv->syscon);
> +
> + return 0;
> +}
> +
> +static void sun8i_emac_unset_syscon(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 reg = 0;
> +
> + if (priv->variant == H3_EMAC)
> + reg = H3_EPHY_DEFAULT_VALUE;
Why do you need that?
> +
> + writel(reg, priv->syscon);
> +}
> +
> +/* Set Management Data Clock, must be call after device reset */
> +static void sun8i_emac_set_mdc(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + unsigned long rate;
> + u32 reg;
> +
> + rate = clk_get_rate(priv->ahb_clk);
> + if (rate > 160000000)
> + reg = 0x3 << 20; /* AHB / 128 */
> + else if (rate > 80000000)
> + reg = 0x2 << 20; /* AHB / 64 */
> + else if (rate > 40000000)
> + reg = 0x1 << 20; /* AHB / 32 */
> + else
> + reg = 0x0 << 20; /* AHB / 16 */
> + netif_dbg(priv, link, ndev, "MDC auto : %x\n", reg);
> + writel(reg, priv->base + SUN8I_EMAC_MDIO_CMD);
You could also expose that as a clock.
> +}
> +
> +/* "power" the device, by enabling clk/reset/regulators */
> +static int sun8i_emac_power(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int ret;
> +
> + ret = clk_prepare_enable(priv->ahb_clk);
> + if (ret) {
> + netdev_err(ndev, "Could not enable AHB clock\n");
> + return ret;
> + }
> +
> + if (priv->rst) {
> + ret = reset_control_deassert(priv->rst);
> + if (ret) {
> + netdev_err(ndev, "Could not deassert reset\n");
> + goto err_reset;
> + }
> + }
> +
> + if (priv->ephy_clk) {
> + ret = clk_prepare_enable(priv->ephy_clk);
> + if (ret) {
> + netdev_err(ndev, "Could not enable EPHY clock\n");
> + goto err_ephy_clk;
> + }
> + }
> +
> + if (priv->rst_ephy) {
> + ret = reset_control_deassert(priv->rst_ephy);
> + if (ret) {
> + netdev_err(ndev, "Could not deassert EPHY reset\n");
> + goto err_ephy_reset;
> + }
> + }
> +
> + return 0;
> +
> +err_ephy_reset:
> + if (priv->ephy_clk)
> + clk_disable_unprepare(priv->ephy_clk);
> +err_ephy_clk:
> + if (priv->rst)
> + reset_control_assert(priv->rst);
> +err_reset:
> + clk_disable_unprepare(priv->ahb_clk);
> + return ret;
> +}
> +
> +/* "Unpower" the device, disabling clocks and regulators, asserting reset */
> +static void sun8i_emac_unpower(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + if (priv->rst_ephy)
> + reset_control_assert(priv->rst_ephy);
> +
> + if (priv->ephy_clk)
> + clk_disable_unprepare(priv->ephy_clk);
> +
> + if (priv->rst)
> + reset_control_assert(priv->rst);
> +
> + clk_disable_unprepare(priv->ahb_clk);
> +}
> +
> +static int sun8i_emac_init(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct device_node *node = priv->dev->of_node;
> + const u8 *addr;
> +
> + /* Try to get MAC address from DT, or assign a random one */
> + addr = of_get_mac_address(node);
> + if (addr)
> + ether_addr_copy(ndev->dev_addr, addr);
> + else
> + eth_hw_addr_random(ndev);
> +
> + priv->phy_interface = of_get_phy_mode(node);
> + if (priv->phy_interface < 0) {
> + netdev_err(ndev, "PHY interface mode node unspecified\n");
> + return priv->phy_interface;
> + }
> +
> + return sun8i_emac_power(ndev);
> +}
> +
> +static void sun8i_emac_uninit(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + mdiobus_unregister(priv->mdio);
> +
> + sun8i_emac_unpower(ndev);
> +}
> +
> +static int sun8i_emac_mdio_probe(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct phy_device *phydev = NULL;
> +
> + phydev = of_phy_connect(ndev, priv->phy_node, &sun8i_emac_adjust_link,
> + 0, priv->phy_interface);
> +
> + if (!phydev) {
> + netdev_err(ndev, "Could not attach to PHY\n");
> + return -ENODEV;
> + }
> +
> + phy_attached_info(phydev);
> +
> + /* mask with MAC supported features */
> + phydev->supported &= PHY_GBIT_FEATURES;
> + phydev->advertising = phydev->supported;
> +
> + priv->link = 0;
> + priv->speed = 0;
> + priv->duplex = -1;
> +
> + return 0;
> +}
> +
> +/* Allocate both RX and TX ring buffer and init them
> + * This function also write the startbase of thoses ring in the device.
> + * All structures that help managing thoses rings are also handled
> + * by this functions (rx_skb/txl)
> + */
> +static int sun8i_emac_alloc_rings(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct dma_desc *ddesc;
> + int err, i;
> +
> + priv->rx_skb = kcalloc(priv->nbdesc_rx, sizeof(struct sk_buff *),
> + GFP_KERNEL);
> + if (!priv->rx_skb) {
> + err = -ENOMEM;
> + goto rx_skb_error;
> + }
> + priv->txl = kcalloc(priv->nbdesc_tx, sizeof(struct txinfo), GFP_KERNEL);
> + if (!priv->txl) {
> + err = -ENOMEM;
> + goto tx_error;
> + }
> +
> + /* allocate/init RX ring */
> + priv->dd_rx = dma_zalloc_coherent(priv->dev,
> + priv->nbdesc_rx * sizeof(struct dma_desc),
> + &priv->dd_rx_phy, GFP_KERNEL);
> + if (!priv->dd_rx) {
> + dev_err(priv->dev, "ERROR: cannot allocate DMA RX buffer");
> + err = -ENOMEM;
> + goto dma_rx_error;
> + }
> + ddesc = priv->dd_rx;
> + for (i = 0; i < priv->nbdesc_rx; i++) {
> + sun8i_emac_rx_skb(ndev, i);
> + ddesc->next = (u32)priv->dd_rx_phy + (i + 1)
> + * sizeof(struct dma_desc);
> + ddesc++;
> + }
> + /* last descriptor point back to first one */
> + ddesc--;
> + ddesc->next = (u32)priv->dd_rx_phy;
> +
> + /* allocate/init TX ring */
> + priv->dd_tx = dma_zalloc_coherent(priv->dev,
> + priv->nbdesc_tx * sizeof(struct dma_desc),
> + &priv->dd_tx_phy, GFP_KERNEL);
> + if (!priv->dd_tx) {
> + dev_err(priv->dev, "ERROR: cannot allocate DMA TX buffer");
> + err = -ENOMEM;
> + goto dma_tx_error;
> + }
> + ddesc = priv->dd_tx;
> + for (i = 0; i < priv->nbdesc_tx; i++) {
> + ddesc->status = DCLEAN;
> + ddesc->ctl = 0;
> + ddesc->next = (u32)(priv->dd_tx_phy + (i + 1)
> + * sizeof(struct dma_desc));
> + ddesc++;
> + }
> + /* last descriptor point back to first one */
> + ddesc--;
> + ddesc->next = (u32)priv->dd_tx_phy;
> + i--;
> +
> + priv->tx_slot = 0;
> + priv->tx_dirty = 0;
> + priv->rx_dirty = 0;
> +
> + /* write start of RX ring descriptor */
> + writel(priv->dd_rx_phy, priv->base + SUN8I_EMAC_RX_DESC_LIST);
> + /* write start of TX ring descriptor */
> + writel(priv->dd_tx_phy, priv->base + SUN8I_EMAC_TX_DESC_LIST);
> +
> + return 0;
> +dma_tx_error:
> + dma_free_coherent(priv->dev, priv->nbdesc_rx * sizeof(struct dma_desc),
> + priv->dd_rx, priv->dd_rx_phy);
> +dma_rx_error:
> + kfree(priv->txl);
> +tx_error:
> + kfree(priv->rx_skb);
> +rx_skb_error:
> + return err;
> +}
> +
> +static int sun8i_emac_open(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int err;
> + u32 v;
> +
> + err = request_irq(priv->irq, sun8i_emac_dma_interrupt, 0,
> + dev_name(priv->dev), ndev);
> + if (err) {
> + dev_err(priv->dev, "Cannot request IRQ: %d\n", err);
> + return err;
> + }
> +
> + /* Set interface mode (and configure internal PHY on H3) */
> + err = sun8i_emac_set_syscon(ndev);
> + if (err)
> + goto err_irq;
> +
> + /* Do SOFT RST */
> + v = readl(priv->base + SUN8I_EMAC_BASIC_CTL1);
> + writel(v | 0x01, priv->base + SUN8I_EMAC_BASIC_CTL1);
> +
> + err = readl_poll_timeout(priv->base + SUN8I_EMAC_BASIC_CTL1, v,
> + !(v & 0x01), 100, 10000);
> + if (err) {
> + dev_err(priv->dev, "EMAC reset timeout\n");
> + err = -EFAULT;
> + goto err_syscon;
> + }
> +
> + sun8i_emac_set_mdc(ndev);
> +
> + err = sun8i_emac_mdio_register(ndev);
> + if (err)
> + goto err_syscon;
> +
> + err = sun8i_emac_mdio_probe(ndev);
> + if (err)
> + goto err_syscon;
> +
> + /* DMA */
> + v = (8 << 24);/* burst len */
> + writel(v, priv->base + SUN8I_EMAC_BASIC_CTL1);
> +
> + writel(RX_INT | TX_INT, priv->base + SUN8I_EMAC_INT_EN);
> +
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL0);
> + /* CHECK_CRC */
> + if (ndev->features & NETIF_F_RXCSUM)
> + v |= SUN8I_EMAC_RX_DO_CRC;
> + else
> + v &= ~SUN8I_EMAC_RX_DO_CRC;
> + /* STRIP_FCS */
> + if (ndev->features & NETIF_F_RXFCS)
> + v &= ~SUN8I_EMAC_RX_STRIP_FCS;
> + else
> + v |= SUN8I_EMAC_RX_STRIP_FCS;
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL0);
> +
> + v = readl(priv->base + SUN8I_EMAC_TX_CTL1);
> + /* TX_MD Transmission starts after a full frame located in TX DMA FIFO*/
> + v |= BIT(1);
> + /* Undocumented bit (called TX_NEXT_FRM in BSP), the original comment is
> + * "Operating on second frame increase the performance
> + * especially when transmit store-and-forward is used."
> + */
> + v |= BIT(2);
Why don't you call it the same then?
> + writel(v, priv->base + SUN8I_EMAC_TX_CTL1);
> +
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL1);
> + /* RX_MD RX DMA reads data from RX DMA FIFO to host memory after a
> + * complete frame has been written to RX DMA FIFO
> + */
> + v |= BIT(1);
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL1);
> +
> + sun8i_emac_set_macaddr(priv, ndev->dev_addr, 0);
> +
> + err = sun8i_emac_alloc_rings(ndev);
> + if (err) {
> + netdev_err(ndev, "Fail to allocate rings\n");
> + goto err_mdio;
> + }
> +
> + phy_start(ndev->phydev);
> +
> + sun8i_emac_start_rx(ndev);
> + sun8i_emac_start_tx(ndev);
> +
> + netif_napi_add(ndev, &priv->napi, sun8i_emac_poll, 64);
> + napi_enable(&priv->napi);
> + netif_start_queue(ndev);
> +
> + return 0;
> +err_mdio:
> + phy_disconnect(ndev->phydev);
> +err_syscon:
> + sun8i_emac_unset_syscon(ndev);
> +err_irq:
> + free_irq(priv->irq, ndev);
> + return err;
> +}
> +
> +/* Clean the TX ring of any accepted skb for xmit */
> +static void sun8i_emac_tx_clean(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int i;
> + struct dma_desc *ddesc;
> + int frame_len;
> +
> + spin_lock(&priv->tx_lock);
> +
> + for (i = 0; i < priv->nbdesc_tx; i++) {
> + if (priv->txl[i].skb) {
> + ddesc = priv->dd_tx + i;
> + frame_len = ddesc->ctl & 0x3FFF;
> + switch (priv->txl[i].map) {
> + case MAP_SINGLE:
> + dma_unmap_single(priv->dev, ddesc->buf_addr,
> + frame_len, DMA_TO_DEVICE);
> + break;
> + case MAP_PAGE:
> + dma_unmap_page(priv->dev, ddesc->buf_addr,
> + frame_len, DMA_TO_DEVICE);
> + break;
> + default:
> + dev_err(priv->dev, "Trying to free an empty slot\n");
> + continue;
> + }
> + dev_kfree_skb_any(priv->txl[i].skb);
> + priv->txl[i].skb = NULL;
> + ddesc->ctl = 0;
> + ddesc->status = DCLEAN;
> + }
> + }
> + priv->tx_slot = 0;
> + priv->tx_dirty = 0;
> +
> + spin_unlock(&priv->tx_lock);
> +}
> +
> +/* Clean the RX ring */
> +static void sun8i_emac_rx_clean(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int i;
> + struct dma_desc *ddesc;
> +
> + /* clean RX ring */
> + for (i = 0; i < priv->nbdesc_rx; i++)
> + if (priv->rx_skb[i]) {
> + ddesc = priv->dd_rx + i;
> + dma_unmap_single(priv->dev, ddesc->buf_addr,
> + DESC_BUF_MAX, DMA_FROM_DEVICE);
> + dev_kfree_skb_any(priv->rx_skb[i]);
> + priv->rx_skb[i] = NULL;
> + }
> +}
> +
> +static int sun8i_emac_stop(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + napi_disable(&priv->napi);
> +
> + sun8i_emac_stop_tx(ndev);
> + sun8i_emac_stop_rx(ndev);
> +
> + phy_stop(ndev->phydev);
> + phy_disconnect(ndev->phydev);
> +
> + sun8i_emac_mdio_unregister(ndev);
> +
> + sun8i_emac_unset_syscon(ndev);
> +
> + free_irq(priv->irq, ndev);
> +
> + sun8i_emac_rx_clean(ndev);
> + sun8i_emac_tx_clean(ndev);
> +
> + kfree(priv->rx_skb);
> + kfree(priv->txl);
> +
> + dma_free_coherent(priv->dev, priv->nbdesc_rx * sizeof(struct dma_desc),
> + priv->dd_rx, priv->dd_rx_phy);
> + dma_free_coherent(priv->dev, priv->nbdesc_tx * sizeof(struct dma_desc),
> + priv->dd_tx, priv->dd_tx_phy);
> +
> + return 0;
> +}
> +
> +static netdev_tx_t sun8i_emac_xmit(struct sk_buff *skb, struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct dma_desc *ddesc;
> + struct dma_desc *first;
> + int i = 0, rbd_first;
> + unsigned int len, fraglen, tlen;
> + u32 v;
> + int n;
> + int nf;
> + const skb_frag_t *frag;
> + int do_csum = 0;
> +
> + if (skb_put_padto(skb, ETH_ZLEN))
> + return NETDEV_TX_OK;
> + len = skb_headlen(skb);
> +
> + n = skb_shinfo(skb)->nr_frags;
> +
> + if (skb->ip_summed == CHECKSUM_PARTIAL) {
> + do_csum = 1;
> + priv->estats.tx_hw_csum++;
> + }
> + netif_dbg(priv, tx_queued, ndev, "%s len=%u skblen=%u %x\n", __func__,
> + len, skb->len,
> + (skb->ip_summed == CHECKSUM_PARTIAL));
> +
> + spin_lock(&priv->tx_lock);
> +
> + /* check for contigous space
> + * We need at least 1(skb->data) + n(numfrags) + 1(one clean slot)
> + */
> + if (rb_tx_numfreedesc(ndev) < n + 2) {
> + dev_err_ratelimited(priv->dev, "BUG!: TX is full %d %d\n",
> + priv->tx_dirty, priv->tx_slot);
> + netif_stop_queue(ndev);
> + spin_unlock(&priv->tx_lock);
> + return NETDEV_TX_BUSY;
> + }
> + i = priv->tx_slot;
> +
> + ddesc = priv->dd_tx + i;
> + first = priv->dd_tx + i;
> + rbd_first = i;
> +
> + priv->tx_slot = (i + 1 + n) % priv->nbdesc_tx;
> +
> + ddesc->buf_addr = dma_map_single(priv->dev, skb->data, len,
> + DMA_TO_DEVICE);
> + if (dma_mapping_error(priv->dev, ddesc->buf_addr)) {
> + dev_err(priv->dev, "ERROR: Cannot map buffer for DMA\n");
> + goto xmit_error;
> + }
> + priv->txl[i].map = MAP_SINGLE;
> + priv->txl[i].skb = skb;
> +
> + tlen = len;
> + ddesc->ctl = len;
> + /* Undocumented bit that make it works
> + * Without it, packets never be sent on H3 SoC
> + */
> + ddesc->ctl |= SUN8I_EMAC_MAGIC_TX_BIT;
> + if (do_csum)
> + ddesc->ctl |= SUN8I_EMAC_TX_DO_CRC;
> +
> + /* handle fragmented skb, one descriptor per fragment */
> + for (nf = 0; nf < n; nf++) {
> + frag = &skb_shinfo(skb)->frags[nf];
> + rb_inc(&i, priv->nbdesc_tx);
> + priv->txl[i].skb = skb;
> + ddesc = priv->dd_tx + i;
> + fraglen = skb_frag_size(frag);
> + ddesc->ctl = fraglen;
> + tlen += fraglen,
> + ddesc->ctl |= SUN8I_EMAC_MAGIC_TX_BIT;
> + if (do_csum)
> + ddesc->ctl |= SUN8I_EMAC_TX_DO_CRC;
> +
> + ddesc->buf_addr = skb_frag_dma_map(priv->dev, frag, 0,
> + fraglen, DMA_TO_DEVICE);
> + if (dma_mapping_error(priv->dev, ddesc->buf_addr)) {
> + dev_err(priv->dev, "Cannot map buffer for DMA\n");
> + goto xmit_error;
> + }
> + priv->txl[i].map = MAP_PAGE;
> + ddesc->status = SUN8I_COULD_BE_USED_BY_DMA;
> + }
> +
> + /* frame end */
> + ddesc->ctl |= DSC_TX_LAST;
> + /* We want an interrupt after transmission */
> + ddesc->ctl |= SUN8I_EMAC_WANT_INT;
> +
> + rb_inc(&i, priv->nbdesc_tx);
> +
> + /* frame begin */
> + first->ctl |= DSC_TX_FIRST;
> + wmb();/* SUN8I_COULD_BE_USED_BY_DMA must be the last value written */
> + first->status = SUN8I_COULD_BE_USED_BY_DMA;
> + priv->tx_slot = i;
> +
> + /* Trying to optimize this (recording DMA start/stop) seems
> + * to lead to errors. So we always start DMA.
> + */
> + v = readl(priv->base + SUN8I_EMAC_TX_CTL1);
> + v |= TX_DMA_START;
> + v |= TX_DMA_EN;
> + writel(v, priv->base + SUN8I_EMAC_TX_CTL1);
> +
> + if (rb_tx_numfreedesc(ndev) < MAX_SKB_FRAGS + 1) {
> + netif_stop_queue(ndev);
> + priv->estats.tx_stop_queue++;
> + }
> + priv->estats.tx_used_desc = rb_tx_numfreedesc(ndev);
> + priv->ndev->stats.tx_packets++;
> + priv->ndev->stats.tx_bytes += tlen;
> +
> + spin_unlock(&priv->tx_lock);
> +
> + return NETDEV_TX_OK;
> +
> +xmit_error:
> + /* destroy skb and return TX OK Documentation/DMA-API-HOWTO.txt */
> + /* clean descritors from rbd_first to i */
> + ddesc->ctl = 0;
> + wmb(); /* setting to DCLEAN is the last value to be set */
> + ddesc->status = DCLEAN;
> + do {
> + ddesc = priv->dd_tx + rbd_first;
> + ddesc->ctl = 0;
> + wmb(); /* setting to DCLEAN is the last value to be set */
> + ddesc->status = DCLEAN;
> + rb_inc(&rbd_first, priv->nbdesc_tx);
> + } while (rbd_first != i);
> + spin_unlock(&priv->tx_lock);
> + dev_kfree_skb_any(skb);
> + return NETDEV_TX_OK;
> +}
> +
> +static int sun8i_emac_change_mtu(struct net_device *ndev, int new_mtu)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int max_mtu;
> +
> + dev_info(priv->dev, "%s set MTU to %d\n", __func__, new_mtu);
> +
> + if (netif_running(ndev)) {
> + dev_err(priv->dev, "%s: must be stopped to change its MTU\n",
> + ndev->name);
> + return -EBUSY;
> + }
> +
> + max_mtu = SKB_MAX_HEAD(NET_SKB_PAD + NET_IP_ALIGN);
> +
> + if ((new_mtu < 68) || (new_mtu > max_mtu)) {
> + dev_err(priv->dev, "%s: invalid MTU, max MTU is: %d\n",
> + ndev->name, max_mtu);
> + return -EINVAL;
> + }
> +
> + ndev->mtu = new_mtu;
> + netdev_update_features(ndev);
> + return 0;
> +}
> +
> +static netdev_features_t sun8i_emac_fix_features(struct net_device *ndev,
> + netdev_features_t features)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + netif_dbg(priv, drv, ndev, "%s %llx\n", __func__, features);
> + return features;
> +}
Looks useless ...
> +
> +static int sun8i_emac_set_features(struct net_device *ndev,
> + netdev_features_t features)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v;
> +
> + v = readl(priv->base + SUN8I_EMAC_BASIC_CTL0);
> + if (features & NETIF_F_LOOPBACK && netif_running(ndev)) {
> + netif_info(priv, hw, ndev, "Set loopback features");
> + v |= BIT(1);
> + } else {
> + netif_info(priv, hw, ndev, "Unset loopback features");
> + v &= ~BIT(1);
> + }
> + writel(v, priv->base + SUN8I_EMAC_BASIC_CTL0);
> +
> + v = readl(priv->base + SUN8I_EMAC_RX_CTL0);
> + if (features & NETIF_F_RXCSUM) {
> + v |= SUN8I_EMAC_RX_DO_CRC;
> + netif_info(priv, hw, ndev, "Doing RX CRC check by hardware");
> + } else {
> + v &= ~SUN8I_EMAC_RX_DO_CRC;
> + netif_info(priv, hw, ndev, "No RX CRC check by hardware");
> + }
> + if (features & NETIF_F_RXFCS) {
> + v &= ~SUN8I_EMAC_RX_STRIP_FCS;
> + netif_info(priv, hw, ndev, "Keep FCS");
> + } else {
> + v |= SUN8I_EMAC_RX_STRIP_FCS;
> + netif_info(priv, hw, ndev, "Strip FCS");
> + }
> + writel(v, priv->base + SUN8I_EMAC_RX_CTL0);
> +
> + netif_dbg(priv, drv, ndev, "%s %llx %x\n", __func__, features, v);
> +
> + return 0;
> +}
> +
> +static void sun8i_emac_set_rx_mode(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v = 0;
> + int i = 0;
> + struct netdev_hw_addr *ha;
> +
> + /* Receive all multicast frames */
> + v |= BIT(16);
> + /* Receive all control frames */
> + v |= BIT(13);
> + if (ndev->flags & IFF_PROMISC)
> + v |= BIT(1);
> + if (netdev_uc_count(ndev) > 7) {
> + v |= BIT(1);
> + } else {
> + netdev_for_each_uc_addr(ha, ndev) {
> + i++;
> + sun8i_emac_set_macaddr(priv, ha->addr, i);
> + }
> + }
> + writel(v, priv->base + SUN8I_EMAC_RX_FRM_FLT);
> +}
> +
> +static void sun8i_emac_tx_timeout(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + netdev_err(ndev, "%s\n", __func__);
> +
> + sun8i_emac_stop_tx(ndev);
> +
> + sun8i_emac_tx_clean(ndev);
> +
> + /* write start of tx ring descriptor */
> + writel(priv->dd_tx_phy, priv->base + SUN8I_EMAC_TX_DESC_LIST);
> +
> + sun8i_emac_start_tx(ndev);
> +
> + netdev_reset_queue(ndev);
> +
> + ndev->stats.tx_errors++;
> + netif_wake_queue(ndev);
> +}
> +
> +static int sun8i_emac_ioctl(struct net_device *ndev, struct ifreq *rq, int cmd)
> +{
> + struct phy_device *phydev = ndev->phydev;
> +
> + if (!netif_running(ndev))
> + return -EINVAL;
> +
> + if (!phydev)
> + return -ENODEV;
> +
> + return phy_mii_ioctl(phydev, rq, cmd);
> +}
> +
> +static int sun8i_emac_check_if_running(struct net_device *ndev)
> +{
> + if (!netif_running(ndev))
> + return -EINVAL;
> + return 0;
> +}
> +static int sun8i_emac_get_sset_count(struct net_device *ndev, int sset)
> +{
> + switch (sset) {
> + case ETH_SS_STATS:
> + return ARRAY_SIZE(estats_str);
> + }
> + return -EOPNOTSUPP;
> +}
> +
> +static int sun8i_emac_ethtool_get_settings(struct net_device *ndev,
> + struct ethtool_cmd *cmd)
> +{
> + struct phy_device *phy = ndev->phydev;
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + if (!phy) {
> + netdev_err(ndev, "%s: %s: PHY is not registered\n",
> + __func__, ndev->name);
> + return -ENODEV;
> + }
> +
> + if (!netif_running(ndev)) {
> + dev_err(priv->dev, "interface disabled: we cannot track link speed / duplex setting\n");
> + return -EBUSY;
> + }
> +
> + return phy_ethtool_gset(phy, cmd);
> +}
> +
> +static int sun8i_emac_ethtool_set_settings(struct net_device *ndev,
> + struct ethtool_cmd *cmd)
> +{
> + struct phy_device *phy = ndev->phydev;
> +
> + return phy_ethtool_sset(phy, cmd);
> +}
> +
> +static void sun8i_emac_ethtool_getdrvinfo(struct net_device *ndev,
> + struct ethtool_drvinfo *info)
> +{
> + strlcpy(info->driver, "sun8i_emac", sizeof(info->driver));
> + strcpy(info->version, "00");
> + info->fw_version[0] = '\0';
> +}
> +
> +static void sun8i_emac_ethtool_stats(struct net_device *ndev,
> + struct ethtool_stats *dummy, u64 *data)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + memcpy(data, &priv->estats,
> + sun8i_emac_get_sset_count(ndev, ETH_SS_STATS) * sizeof(u64));
> +}
> +
> +static void sun8i_emac_ethtool_strings(struct net_device *dev, u32 stringset,
> + u8 *buffer)
> +{
> + switch (stringset) {
> + case ETH_SS_STATS:
> + memcpy(buffer, &estats_str, sizeof(estats_str));
> + break;
> + }
> +}
> +
> +static u32 sun8i_emac_ethtool_getmsglevel(struct net_device *ndev)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + return priv->msg_enable;
> +}
> +
> +static void sun8i_emac_ethtool_setmsglevel(struct net_device *ndev, u32 level)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + priv->msg_enable = level;
> +}
> +
> +static void sun8i_emac_get_pauseparam(struct net_device *ndev,
> + struct ethtool_pauseparam *pause)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + pause->rx_pause = 0;
> + pause->tx_pause = 0;
> + pause->autoneg = ndev->phydev->autoneg;
> +
> + if (priv->flow_ctrl & FLOW_RX)
> + pause->rx_pause = 1;
> + if (priv->flow_ctrl & FLOW_TX)
> + pause->tx_pause = 1;
> +}
> +
> +static int sun8i_emac_set_pauseparam(struct net_device *ndev,
> + struct ethtool_pauseparam *pause)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + struct phy_device *phy = ndev->phydev;
> + int new_pause = 0;
> + int ret = 0;
> +
> + if (pause->rx_pause)
> + new_pause |= FLOW_RX;
> + if (pause->tx_pause)
> + new_pause |= FLOW_TX;
> +
> + priv->flow_ctrl = new_pause;
> + phy->autoneg = pause->autoneg;
> +
> + if (phy->autoneg) {
> + if (netif_running(ndev))
> + ret = phy_start_aneg(phy);
> + } else {
> + sun8i_emac_flow_ctrl(priv, phy->duplex, priv->flow_ctrl);
> + }
> + return ret;
> +}
> +
> +static void sun8i_emac_ethtool_get_ringparam(struct net_device *ndev,
> + struct ethtool_ringparam *ring)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> +
> + ring->rx_pending = priv->nbdesc_rx;
> + ring->tx_pending = priv->nbdesc_tx;
> +}
> +
> +static int sun8i_emac_ethtool_set_ringparam(struct net_device *ndev,
> + struct ethtool_ringparam *ring)
> +{
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + int err;
> +
> + if (ring->rx_max_pending || ring->rx_mini_max_pending ||
> + ring->rx_jumbo_max_pending || ring->rx_mini_pending ||
> + ring->rx_jumbo_pending || ring->tx_max_pending)
> + return -EINVAL;
> +
> + if (ring->tx_pending < MAX_SKB_FRAGS + 1) {
> + netdev_err(ndev, "The number of TX descriptors is too low");
> + return -EINVAL;
> + }
> +
> + sun8i_emac_stop_tx(ndev);
> + sun8i_emac_stop_rx(ndev);
> +
> + sun8i_emac_rx_clean(ndev);
> + sun8i_emac_tx_clean(ndev);
> +
> + kfree(priv->rx_skb);
> + kfree(priv->txl);
> +
> + dma_free_coherent(priv->dev, priv->nbdesc_rx * sizeof(struct dma_desc),
> + priv->dd_rx, priv->dd_rx_phy);
> + dma_free_coherent(priv->dev, priv->nbdesc_tx * sizeof(struct dma_desc),
> + priv->dd_tx, priv->dd_tx_phy);
> +
> + priv->nbdesc_rx = ring->rx_pending;
> + priv->nbdesc_tx = ring->tx_pending;
> + err = sun8i_emac_alloc_rings(ndev);
> + if (err) {
> + /* Fatal error, we cannot re start */
> + netdev_err(ndev, "Fail to allocate rings\n");
> + return -EFAULT;
> + }
> +
> + sun8i_emac_start_rx(ndev);
> + sun8i_emac_start_tx(ndev);
> +
> + netif_start_queue(ndev);
> +
> + netdev_info(ndev, "Ring Param settings: rx: %d, tx %d\n",
> + ring->rx_pending, ring->tx_pending);
> + return 0;
> +}
> +
> +static const struct ethtool_ops sun8i_emac_ethtool_ops = {
> + .begin = sun8i_emac_check_if_running,
> + .get_settings = sun8i_emac_ethtool_get_settings,
> + .set_settings = sun8i_emac_ethtool_set_settings,
> + .get_link = ethtool_op_get_link,
> + .get_pauseparam = sun8i_emac_get_pauseparam,
> + .set_pauseparam = sun8i_emac_set_pauseparam,
> + .get_ethtool_stats = sun8i_emac_ethtool_stats,
> + .get_strings = sun8i_emac_ethtool_strings,
> + .get_sset_count = sun8i_emac_get_sset_count,
> + .get_drvinfo = sun8i_emac_ethtool_getdrvinfo,
> + .get_msglevel = sun8i_emac_ethtool_getmsglevel,
> + .set_msglevel = sun8i_emac_ethtool_setmsglevel,
> + .get_ringparam = sun8i_emac_ethtool_get_ringparam,
> + .set_ringparam = sun8i_emac_ethtool_set_ringparam,
> +};
> +
> +static const struct net_device_ops sun8i_emac_netdev_ops = {
> + .ndo_init = sun8i_emac_init,
> + .ndo_uninit = sun8i_emac_uninit,
> + .ndo_open = sun8i_emac_open,
> + .ndo_start_xmit = sun8i_emac_xmit,
> + .ndo_stop = sun8i_emac_stop,
> + .ndo_change_mtu = sun8i_emac_change_mtu,
> + .ndo_fix_features = sun8i_emac_fix_features,
> + .ndo_set_features = sun8i_emac_set_features,
> + .ndo_set_rx_mode = sun8i_emac_set_rx_mode,
> + .ndo_tx_timeout = sun8i_emac_tx_timeout,
> + .ndo_do_ioctl = sun8i_emac_ioctl,
> + .ndo_set_mac_address = eth_mac_addr,
> +};
> +
> +static irqreturn_t sun8i_emac_dma_interrupt(int irq, void *dev_id)
> +{
> + struct net_device *ndev = dev_id;
> + struct sun8i_emac_priv *priv = netdev_priv(ndev);
> + u32 v, u;
> +
> + v = readl(priv->base + SUN8I_EMAC_INT_STA);
> +
> + /* When this bit is asserted, a frame transmission is completed. */
> + if (v & BIT(0)) {
> + priv->estats.tx_int++;
> + writel(0, priv->base + SUN8I_EMAC_INT_EN);
> + napi_schedule(&priv->napi);
> + }
> +
> + /* When this bit is asserted, the TX DMA FSM is stopped. */
> + if (v & BIT(1))
> + priv->estats.tx_dma_stop++;
> +
> + /* When this asserted, the TX DMA can not acquire next TX descriptor
> + * and TX DMA FSM is suspended.
> + */
> + if (v & BIT(2))
> + priv->estats.tx_dma_ua++;
> +
> + if (v & BIT(3))
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt TX TIMEOUT\n");
Why do you enable that interrupt if you can't handle it?
And printing in the interrupt handler is a very bad idea.
> + if (v & BIT(4)) {
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt TX underflow\n");
> + priv->estats.tx_underflow_int++;
> + }
> +
> + /* When this bit asserted , the frame is transmitted to FIFO totally. */
> + if (v & BIT(5)) {
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt TX_EARLY_INT\n");
> + priv->estats.tx_early_int++;
> + }
> +
> + /* When this bit is asserted, a frame reception is completed */
> + if (v & BIT(8)) {
> + priv->estats.rx_int++;
> + writel(0, priv->base + SUN8I_EMAC_INT_EN);
> + napi_schedule(&priv->napi);
> + }
> +
> + /* When this asserted, the RX DMA can not acquire next TX descriptor
> + * and RX DMA FSM is suspended.
> + */
> + if (v & BIT(9)) {
> + u = readl(priv->base + SUN8I_EMAC_RX_CTL1);
> + netif_info(priv, intr, ndev, "Re-run RX DMA %x\n", u);
Seriously?
> + writel(u | RX_DMA_START, priv->base + SUN8I_EMAC_RX_CTL1);
> + priv->estats.rx_dma_ua++;
> + }
> +
> + if (v & BIT(10)) {
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt RX_DMA_STOPPED_INT\n");
> + priv->estats.rx_dma_stop++;
> + }
> + if (v & BIT(11))
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt RX_TIMEOUT\n");
> + if (v & BIT(12))
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt RX OVERFLOW\n");
> + if (v & BIT(13)) {
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt RX EARLY\n");
> + priv->estats.rx_early_int++;
> + }
> + if (v & BIT(16))
> + netif_dbg(priv, intr, ndev, "Unhandled interrupt RGMII\n");
> +
> + /* the datasheet state those register as read-only
> + * but nothing work(freeze) without writing to it
> + */
> + writel(v & 0x3FFF, priv->base + SUN8I_EMAC_INT_STA);
Why don't you just write what you read?
> +
> + return IRQ_HANDLED;
The lack of spinlocks in there is quite worrying.
> +}
> +
> +static int sun8i_emac_probe(struct platform_device *pdev)
> +{
> + struct device_node *node = pdev->dev.of_node;
> + struct sun8i_emac_priv *priv;
> + struct net_device *ndev;
> + struct resource *res;
> + int ret;
> +
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + if (ret) {
> + dev_err(&pdev->dev, "No suitable DMA available\n");
> + return ret;
> + }
Isn't that the default?
> + ndev = alloc_etherdev(sizeof(*priv));
> + if (!ndev)
> + return -ENOMEM;
> +
> + SET_NETDEV_DEV(ndev, &pdev->dev);
> + priv = netdev_priv(ndev);
> + platform_set_drvdata(pdev, ndev);
> +
> + priv->variant = (enum emac_variant)of_device_get_match_data(&pdev->dev);
> + if (!priv->variant) {
> + dev_err(&pdev->dev, "Missing sun8i-emac variant\n");
> + return -EINVAL;
> + }
> +
> + priv->phy_node = of_parse_phandle(node, "phy", 0);
> + if (!priv->phy_node) {
> + netdev_err(ndev, "No associated PHY\n");
> + return -ENODEV;
> + }
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + priv->base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(priv->base)) {
> + ret = PTR_ERR(priv->base);
> + dev_err(&pdev->dev, "Cannot request MMIO: %d\n", ret);
> + return ret;
> + }
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscon");
> + priv->syscon = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(priv->syscon)) {
> + ret = PTR_ERR(priv->syscon);
> + dev_err(&pdev->dev,
> + "Cannot map system control registers: %d\n", ret);
> + return ret;
> + }
> +
> + priv->ahb_clk = devm_clk_get(&pdev->dev, "ahb");
> + if (IS_ERR(priv->ahb_clk)) {
> + ret = PTR_ERR(priv->ahb_clk);
> + dev_err(&pdev->dev, "Cannot get AHB clock err=%d\n", ret);
> + goto probe_err;
> + }
> +
> + priv->rst = devm_reset_control_get_optional(&pdev->dev, "ahb");
> + if (IS_ERR(priv->rst)) {
> + ret = PTR_ERR(priv->rst);
> + if (ret == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> + dev_info(&pdev->dev, "No MAC reset control found %d\n", ret);
> + priv->rst = NULL;
> + }
> +
> + if (priv->variant == H3_EMAC)
> + priv->use_internal_phy = of_property_read_bool(node,
> + "allwinner,use-internal-phy");
> +
> + if (priv->use_internal_phy) {
> + priv->ephy_clk = devm_clk_get(&pdev->dev, "ephy");
> + if (IS_ERR(priv->ephy_clk)) {
> + ret = PTR_ERR(priv->ephy_clk);
> + dev_err(&pdev->dev, "Cannot get EPHY clock err=%d\n",
> + ret);
> + goto probe_err;
> + }
> +
> + priv->rst_ephy = devm_reset_control_get_optional(&pdev->dev,
> + "ephy");
> + if (IS_ERR(priv->rst_ephy)) {
> + ret = PTR_ERR(priv->rst_ephy);
> + if (ret == -EPROBE_DEFER)
> + goto probe_err;
> + dev_info(&pdev->dev,
> + "No EPHY reset control found %d\n", ret);
> + priv->rst_ephy = NULL;
> + }
> + }
> +
> + priv->irq = platform_get_irq(pdev, 0);
> + if (priv->irq < 0) {
> + ret = priv->irq;
> + dev_err(&pdev->dev, "Cannot claim IRQ: %d\n", ret);
> + goto probe_err;
> + }
> +
> + spin_lock_init(&priv->tx_lock);
> +
> + ndev->netdev_ops = &sun8i_emac_netdev_ops;
> + ndev->ethtool_ops = &sun8i_emac_ethtool_ops;
> +
> + priv->ndev = ndev;
> + priv->dev = &pdev->dev;
> +
> + ndev->hw_features = NETIF_F_SG | NETIF_F_HIGHDMA;
> + ndev->hw_features |= NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
> + NETIF_F_RXCSUM;
> + ndev->features |= ndev->hw_features;
> + ndev->hw_features |= NETIF_F_RXFCS;
> + ndev->hw_features |= NETIF_F_RXALL;
> + ndev->hw_features |= NETIF_F_LOOPBACK;
> + ndev->priv_flags |= IFF_UNICAST_FLT;
> +
> + ndev->watchdog_timeo = msecs_to_jiffies(5000);
> + netif_carrier_off(ndev);
> +
> + /* Benched on OPIPC with 100M, setting more than 256 does not give any
> + * perf boost
> + */
> + priv->nbdesc_rx = 128;
> + priv->nbdesc_tx = 256;
> +
> + ret = register_netdev(ndev);
> + if (ret) {
> + dev_err(&pdev->dev, "ERROR: Register %s failed\n", ndev->name);
> + goto probe_err;
> + }
> +
> + return 0;
> +
> +probe_err:
> + free_netdev(ndev);
> + return ret;
> +}
> +
> +static int sun8i_emac_remove(struct platform_device *pdev)
> +{
> + struct net_device *ndev = platform_get_drvdata(pdev);
> +
> + unregister_netdev(ndev);
> + platform_set_drvdata(pdev, NULL);
> + free_netdev(ndev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id sun8i_emac_of_match_table[] = {
> + { .compatible = "allwinner,sun8i-a83t-emac",
> + .data = (void *)A83T_EMAC },
> + { .compatible = "allwinner,sun8i-h3-emac",
> + .data = (void *)H3_EMAC },
> + { .compatible = "allwinner,sun50i-a64-emac",
> + .data = (void *)A64_EMAC },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, sun8i_emac_of_match_table);
> +
> +static struct platform_driver sun8i_emac_driver = {
> + .probe = sun8i_emac_probe,
> + .remove = sun8i_emac_remove,
> + .driver = {
> + .name = "sun8i-emac",
> + .of_match_table = sun8i_emac_of_match_table,
> + },
> +};
> +
> +module_platform_driver(sun8i_emac_driver);
> +
> +MODULE_DESCRIPTION("sun8i Ethernet driver");
> +MODULE_LICENSE("GPL");
> +MODULE_AUTHOR("LABBE Corentin <clabbe.montjoie@xxxxxxxxx");
Having runtime_pm working would be great.
Thanks!
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
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