Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754616Ab3CXTEM (ORCPT ); Sun, 24 Mar 2013 15:04:12 -0400 Received: from mail-wi0-f171.google.com ([209.85.212.171]:49625 "EHLO mail-wi0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754062Ab3CXTEK convert rfc822-to-8bit (ORCPT ); Sun, 24 Mar 2013 15:04:10 -0400 From: Florian Fainelli To: linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 1/5] net: Add EMAC ethernet driver found on Allwinner A10 SoC's Date: Sun, 24 Mar 2013 20:03:52 +0100 User-Agent: KMail/1.13.7 (Linux/3.7-trunk-amd64; KDE/4.8.4; x86_64; ; ) Cc: Maxime Ripard , linux-doc@vger.kernel.org, Alejandro Mery , netdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, Rob Herring , Grant Likely , Rob Landley , sunny@allwinnertech.com, shuge@allwinnertech.com, Stefan Roese , kevin@allwinnertech.com References: <1364077814-2233-1-git-send-email-maxime.ripard@free-electrons.com> <1364077814-2233-2-git-send-email-maxime.ripard@free-electrons.com> In-Reply-To: <1364077814-2233-2-git-send-email-maxime.ripard@free-electrons.com> Organization: OpenWrt MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 8BIT Message-Id: <201303242003.52827.florian@openwrt.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 11956 Lines: 398 Hello, Your phylib implementation looks good now, just some minor comments below: Le samedi 23 mars 2013 23:30:10, Maxime Ripard a ?crit : > From: Stefan Roese > > The Allwinner A10 has an ethernet controller that seem to be developped > internally by them. > > The exact feature set of this controller is unknown, since there is no > public documentation for this IP, and this driver is mostly the one > published by Allwinner that has been heavily cleaned up. > > Signed-off-by: Stefan Roese > Signed-off-by: Maxime Ripard > --- > .../bindings/net/allwinner,sun4i-emac.txt | 19 + > drivers/net/ethernet/Kconfig | 1 + > drivers/net/ethernet/Makefile | 1 + > drivers/net/ethernet/allwinner/Kconfig | 36 + > drivers/net/ethernet/allwinner/Makefile | 5 + > drivers/net/ethernet/allwinner/sun4i-emac.c | 1033 > ++++++++++++++++++++ drivers/net/ethernet/allwinner/sun4i-emac.h | > 114 +++ > 7 files changed, 1209 insertions(+) > create mode 100644 > Documentation/devicetree/bindings/net/allwinner,sun4i-emac.txt create mode > 100644 drivers/net/ethernet/allwinner/Kconfig > create mode 100644 drivers/net/ethernet/allwinner/Makefile > create mode 100644 drivers/net/ethernet/allwinner/sun4i-emac.c > create mode 100644 drivers/net/ethernet/allwinner/sun4i-emac.h > > diff --git a/Documentation/devicetree/bindings/net/allwinner,sun4i-emac.txt > b/Documentation/devicetree/bindings/net/allwinner,sun4i-emac.txt new file > mode 100644 > index 0000000..aaf5013 > --- /dev/null > +++ b/Documentation/devicetree/bindings/net/allwinner,sun4i-emac.txt > @@ -0,0 +1,19 @@ > +* Allwinner EMAC ethernet controller > + > +Required properties: > +- compatible: should be "allwinner,sun4i-emac". > +- reg: address and length of the register set for the device. > +- interrupts: interrupt for the device > + > +Optional properties: > +- phy-supply: phandle to a regulator if the PHY needs one > +- (local-)mac-address: mac address to be used by this driver > + > +Example: > + > +emac: ethernet@01c0b000 { > + compatible = "allwinner,sun4i-emac"; > + reg = <0x01c0b000 0x1000>; > + phy-supply = <®_emac_3v3>; > + interrupts = <55>; Also include a standard PHY device tree binding and use the device tree helpers to find and connect to your PHY device. [snip] > +if NET_VENDOR_ALLWINNER > + > +config SUN4I_EMAC > + tristate "Allwinner A10 EMAC support" > + depends on ARCH_SUNXI > + depends on OF > + select CRC32 > + select NET_CORE > + select MII You should select PHYLIB now that you implement it. [snip] > +static int emac_mdio_read(struct mii_bus *bus, int mii_id, int regnum) > +{ > + struct emac_board_info *db = bus->priv; > + int value; > + > + /* issue the phy address and reg */ > + writel((mii_id << 8) | regnum, db->membase + EMAC_MAC_MADR_REG); > + /* pull up the phy io line */ > + writel(0x1, db->membase + EMAC_MAC_MCMD_REG); > + > + /* Wait read complete */ > + while (readl(db->membase + EMAC_MAC_MIND_REG) & 0x1) > + cpu_relax(); This needs proper timeout handling. > + > + /* push down the phy io line */ > + writel(0x0, db->membase + EMAC_MAC_MCMD_REG); > + /* and read data */ > + value = readl(db->membase + EMAC_MAC_MRDD_REG); > + > + return value; > +} > + > +static int emac_mdio_write(struct mii_bus *bus, int mii_id, int regnum, > + u16 value) > +{ > + struct emac_board_info *db = bus->priv; > + > + /* issue the phy address and reg */ > + writel((mii_id << 8) | regnum, db->membase + EMAC_MAC_MADR_REG); > + /* pull up the phy io line */ > + writel(0x1, db->membase + EMAC_MAC_MCMD_REG); > + > + /* Wait read complete */ > + while (readl(db->membase + EMAC_MAC_MIND_REG) & 0x1) > + cpu_relax(); Same here. [snip] > +static void emac_init_emac(struct net_device *dev); > +static void emac_handle_link_change(struct net_device *dev) > +{ > + struct emac_board_info *db = netdev_priv(dev); > + struct phy_device *phydev = db->phy_dev; > + unsigned long flags; > + int status_change = 0; > + > + spin_lock_irqsave(&db->lock, flags); a phylib adjust_link callback is already called with a mutex hold, so your spinlock could be moved down to emac_init_emac() where the RMW sequence is performed. > + > + if (phydev->link) { > + if ((db->speed != phydev->speed) || > + (db->duplex != phydev->duplex)) { > + /* Re-init EMAC with new settings */ > + emac_init_emac(dev); emac_init_emac() (the name could be change BTW) is not just changing the duplex setting of the MAC but also touches the transmitter/receiver enable bits, is that what you want as well? [snip] > +static int emac_mii_probe(struct net_device *dev) > +{ > + struct emac_board_info *db = netdev_priv(dev); > + struct phy_device *phydev; > + int ret; > + > + phydev = phy_find_first(db->mii_bus); > + if (!phydev) { > + netdev_err(dev, "no PHY found\n"); > + return -1; > + } > + > + /* to-do: PHY interrupts are currently not supported */ > + > + /* attach the mac to the phy */ > + ret = phy_connect_direct(dev, phydev, &emac_handle_link_change, > + db->phy_interface); > + if (ret) { > + netdev_err(dev, "Could not attach to PHY\n"); > + return ret; > + } You could use of_phy_connect() here to eliminate some boilerplate code. [snip] > +unsigned int emac_powerup(struct net_device *ndev) > +{ > + struct emac_board_info *db = netdev_priv(ndev); > + unsigned int reg_val; > + > + /* initial EMAC */ > + /* flush RX FIFO */ > + reg_val = readl(db->membase + EMAC_RX_CTL_REG); > + reg_val |= 0x8; > + writel(reg_val, db->membase + EMAC_RX_CTL_REG); > + udelay(1); > + > + /* initial MAC */ > + /* soft reset MAC */ > + reg_val = readl(db->membase + EMAC_MAC_CTL0_REG); > + reg_val &= ~EMAC_MAC_CTL0_SOFT_RESET; > + writel(reg_val, db->membase + EMAC_MAC_CTL0_REG); > + > + /* set MII clock */ > + reg_val = readl(db->membase + EMAC_MAC_MCFG_REG); > + reg_val &= (~(0xf << 2)); > + reg_val |= (0xD << 2); > + writel(reg_val, db->membase + EMAC_MAC_MCFG_REG); > + > + /* clear RX counter */ > + writel(0x0, db->membase + EMAC_RX_FBC_REG); > + > + /* disable all interrupt and clear interrupt status */ > + writel(0, db->membase + EMAC_INT_CTL_REG); > + reg_val = readl(db->membase + EMAC_INT_STA_REG); > + writel(reg_val, db->membase + EMAC_INT_STA_REG); > + > + udelay(1); > + > + /* set up EMAC */ > + emac_setup(ndev); > + > + /* set mac_address to chip */ > + writel(ndev->dev_addr[0] << 16 | ndev->dev_addr[1] << 8 | ndev-> > + dev_addr[2], db->membase + EMAC_MAC_A1_REG); > + writel(ndev->dev_addr[3] << 16 | ndev->dev_addr[4] << 8 | ndev-> > + dev_addr[5], db->membase + EMAC_MAC_A0_REG); > + > + mdelay(1); > + > + return 1; Either return 0 to be consistent, or do not return anything [snip] > +static int emac_start_xmit(struct sk_buff *skb, struct net_device *dev) > +{ > + struct emac_board_info *db = netdev_priv(dev); > + unsigned long channel; > + unsigned long flags; > + > + channel = db->tx_fifo_stat & 3; > + if (channel == 3) > + return NETDEV_TX_BUSY; NETDEV_TX_BUSY really is a hard condition, your initial submission had something like netif_stop_queue(dev) and return 1 and this was actually better. [snip] > + > +/* Received a packet and pass to upper layer > + */ > +static void emac_rx(struct net_device *dev) > +{ > + struct emac_board_info *db = netdev_priv(dev); > + struct sk_buff *skb; > + u8 *rdptr; > + bool good_packet; > + static int rxlen_last; > + unsigned int reg_val; > + u32 rxhdr, rxstatus, rxcount, rxlen; > + > + /* Check packet ready or not */ > + while (1) { > + /* race warning: the first packet might arrive with > + * the interrupts disabled, but the second will fix > + * it > + */ > + rxcount = readl(db->membase + EMAC_RX_FBC_REG); > + > + if (netif_msg_rx_status(db)) > + dev_dbg(db->dev, "RXCount: %x\n", rxcount); > + > + if ((db->skb_last != NULL) && (rxlen_last > 0)) { > + dev->stats.rx_bytes += rxlen_last; > + > + /* Pass to upper layer */ > + db->skb_last->protocol = eth_type_trans(db->skb_last, > + dev); > + netif_rx(db->skb_last); > + dev->stats.rx_packets++; > + db->skb_last = NULL; > + rxlen_last = 0; > + > + reg_val = readl(db->membase + EMAC_RX_CTL_REG); > + reg_val &= ~EMAC_RX_CTL_DMA_EN; > + writel(reg_val, db->membase + EMAC_RX_CTL_REG); > + } > + > + if (!rxcount) { > + db->emacrx_completed_flag = 1; > + reg_val = readl(db->membase + EMAC_INT_CTL_REG); > + reg_val |= (0xf << 0) | (0x01 << 8); > + writel(reg_val, db->membase + EMAC_INT_CTL_REG); > + > + /* had one stuck? */ > + rxcount = readl(db->membase + EMAC_RX_FBC_REG); > + if (!rxcount) > + return; > + } > + > + reg_val = readl(db->membase + EMAC_RX_IO_DATA_REG); > + if (netif_msg_rx_status(db)) > + dev_dbg(db->dev, "receive header: %x\n", reg_val); > + if (reg_val != EMAC_UNDOCUMENTED_MAGIC) { > + /* disable RX */ > + reg_val = readl(db->membase + EMAC_CTL_REG); > + writel(reg_val & ~EMAC_CTL_RX_EN, > + db->membase + EMAC_CTL_REG); > + > + /* Flush RX FIFO */ > + reg_val = readl(db->membase + EMAC_RX_CTL_REG); > + writel(reg_val | (1 << 3), > + db->membase + EMAC_RX_CTL_REG); > + > + do { > + reg_val = readl(db->membase + EMAC_RX_CTL_REG); > + } while (reg_val & (1 << 3)); > + > + /* enable RX */ > + reg_val = readl(db->membase + EMAC_CTL_REG); > + writel(reg_val | EMAC_CTL_RX_EN, > + db->membase + EMAC_CTL_REG); > + reg_val = readl(db->membase + EMAC_INT_CTL_REG); > + reg_val |= (0xf << 0) | (0x01 << 8); > + writel(reg_val, db->membase + EMAC_INT_CTL_REG); > + > + db->emacrx_completed_flag = 1; > + > + return; > + } > + > + /* A packet ready now & Get status/length */ > + good_packet = true; > + > + emac_inblk_32bit(db->membase + EMAC_RX_IO_DATA_REG, > + &rxhdr, sizeof(rxhdr)); > + > + if (netif_msg_rx_status(db)) > + dev_dbg(db->dev, "rxhdr: %x\n", *((int *)(&rxhdr))); > + > + rxlen = EMAC_RX_IO_DATA_LEN(rxhdr); > + rxstatus = EMAC_RX_IO_DATA_STATUS(rxhdr); > + > + if (netif_msg_rx_status(db)) > + dev_dbg(db->dev, "RX: status %02x, length %04x\n", > + rxstatus, rxlen); > + > + /* Packet Status check */ > + if (rxlen < 0x40) { > + good_packet = false; > + if (netif_msg_rx_err(db)) > + dev_dbg(db->dev, "RX: Bad Packet (runt)\n"); > + } > + > + if (unlikely(!(rxstatus & EMAC_RX_IO_DATA_STATUS_OK))) { > + good_packet = false; > + > + if (rxstatus & EMAC_RX_IO_DATA_STATUS_CRC_ERR) { > + if (netif_msg_rx_err(db)) > + dev_dbg(db->dev, "crc error\n"); > + dev->stats.rx_crc_errors++; > + } > + > + if (rxstatus & EMAC_RX_IO_DATA_STATUS_LEN_ERR) { > + if (netif_msg_rx_err(db)) > + dev_dbg(db->dev, "length error\n"); > + dev->stats.rx_length_errors++; > + } > + } > + > + /* Move data from EMAC */ > + skb = dev_alloc_skb(rxlen + 4); > + if (good_packet && skb) { > + skb_reserve(skb, 2); > + rdptr = (u8 *) skb_put(skb, rxlen - 4); > + > + /* Read received packet from RX SRAM */ > + if (netif_msg_rx_status(db)) > + dev_dbg(db->dev, "RxLen %x\n", rxlen); > + > + emac_inblk_32bit(db->membase + EMAC_RX_IO_DATA_REG, > + rdptr, rxlen); > + dev->stats.rx_bytes += rxlen; > + > + /* Pass to upper layer */ > + skb->protocol = eth_type_trans(skb, dev); > + netif_rx(skb); > + dev->stats.rx_packets++; > + } > + } > +} > + > +static irqreturn_t emac_interrupt(int irq, void *dev_id) > +{ You should implement NAPI, you do not have much to change to actually be able to do it. > + netif_stop_queue(ndev); > + netif_carrier_off(ndev); phy_stop() is missing here. -- Florian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/