From mboxrd@z Thu Jan 1 00:00:00 1970 From: Max Schwarz Subject: Re: [PATCH 2/2] arc_emac: add clock handling Date: Wed, 23 Apr 2014 23:39:26 +0200 Message-ID: <4205607.5MYc0BULKu@typ> References: <2479609.DglKFY1Bsn@phil> <21852569.EUtq6ntoe2@phil> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "David S. Miller" , Alexey Brodkin , netdev@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala To: Heiko =?ISO-8859-1?Q?St=FCbner?= Return-path: Received: from moutng.kundenserver.de ([212.227.17.13]:55536 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751017AbaDWVjs convert rfc822-to-8bit (ORCPT ); Wed, 23 Apr 2014 17:39:48 -0400 In-Reply-To: <21852569.EUtq6ntoe2@phil> Sender: netdev-owner@vger.kernel.org List-ID: On Wednesday 23 April 2014 at 14:24:55, Heiko St=FCbner wrote: > This adds ability for the arc_emac to really handle its supplying clo= ck. > To get the needed clock-frequency either a real clock or the previous > clock-frequency property must be provided. >=20 > Signed-off-by: Heiko Stuebner > --- > Documentation/devicetree/bindings/net/arc_emac.txt | 12 +++++- > drivers/net/ethernet/arc/emac.h | 2 + > drivers/net/ethernet/arc/emac_main.c | 46 > ++++++++++++++++------ 3 files changed, 47 insertions(+), 13 deletion= s(-) >=20 > diff --git a/Documentation/devicetree/bindings/net/arc_emac.txt > b/Documentation/devicetree/bindings/net/arc_emac.txt index 7fbb027..a= 1d71eb > 100644 > --- a/Documentation/devicetree/bindings/net/arc_emac.txt > +++ b/Documentation/devicetree/bindings/net/arc_emac.txt > @@ -4,11 +4,15 @@ Required properties: > - compatible: Should be "snps,arc-emac" > - reg: Address and length of the register set for the device > - interrupts: Should contain the EMAC interrupts > -- clock-frequency: CPU frequency. It is needed to calculate and set = polling > -period of EMAC. > - max-speed: see ethernet.txt file in the same directory. > - phy: see ethernet.txt file in the same directory. >=20 > +Clock handling: > +The clock frequency is needed to calculate and set polling period of= EMAC. > +It must be provided by one of: > +- clock-frequency: CPU frequency. > +- clocks: reference to the clock supplying the EMAC. > + > Child nodes of the driver are the individual PHY devices connected t= o the > MDIO bus. They must have a "reg" property given the PHY address on t= he MDIO > bus. >=20 > @@ -19,7 +23,11 @@ Examples: > reg =3D <0xc0fc2000 0x3c>; > interrupts =3D <6>; > mac-address =3D [ 00 11 22 33 44 55 ]; > + > clock-frequency =3D <80000000>; > + /* or */ > + clocks =3D <&emac_clock>; > + > max-speed =3D <100>; > phy =3D <&phy0>; >=20 > diff --git a/drivers/net/ethernet/arc/emac.h > b/drivers/net/ethernet/arc/emac.h index 928fac6..53f85bf 100644 > --- a/drivers/net/ethernet/arc/emac.h > +++ b/drivers/net/ethernet/arc/emac.h > @@ -11,6 +11,7 @@ > #include > #include > #include > +#include >=20 > /* STATUS and ENABLE Register bit masks */ > #define TXINT_MASK (1<<0) /* Transmit interrupt */ > @@ -131,6 +132,7 @@ struct arc_emac_priv { > struct mii_bus *bus; >=20 > void __iomem *regs; > + struct clk *clk; >=20 > struct napi_struct napi; > struct net_device_stats stats; > diff --git a/drivers/net/ethernet/arc/emac_main.c > b/drivers/net/ethernet/arc/emac_main.c index 0cba97a..68f8ad5 100644 > --- a/drivers/net/ethernet/arc/emac_main.c > +++ b/drivers/net/ethernet/arc/emac_main.c > @@ -649,13 +649,6 @@ static int arc_emac_probe(struct platform_device= *pdev) > return -ENODEV; > } >=20 > - /* Get CPU clock frequency from device tree */ > - if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", > - &clock_frequency)) { > - dev_err(&pdev->dev, "failed to retrieve from dev= ice > tree\n"); - return -EINVAL; > - } > - > /* Get IRQ from device tree */ > irq =3D irq_of_parse_and_map(pdev->dev.of_node, 0); > if (!irq) { > @@ -687,13 +680,32 @@ static int arc_emac_probe(struct platform_devic= e > *pdev) } > dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs)= ; >=20 > + priv->clk =3D of_clk_get(pdev->dev.of_node, 0); > + if (IS_ERR(priv->clk)) { > + /* Get CPU clock frequency from device tree */ > + if (of_property_read_u32(pdev->dev.of_node, "clock-frequency", > + &clock_frequency)) { > + dev_err(&pdev->dev, "failed to retrieve from de= vice > tree\n"); + err =3D -EINVAL; > + goto out_netdev; > + } > + } else { > + err =3D clk_prepare_enable(priv->clk); > + if (err) { > + dev_err(&pdev->dev, "failed to enable clock\n"); > + goto out_clkget; > + } > + > + clock_frequency =3D clk_get_rate(priv->clk); > + } > + > id =3D arc_reg_get(priv, R_ID); >=20 > /* Check for EMAC revision 5 or 7, magic number */ > if (!(id =3D=3D 0x0005fd02 || id =3D=3D 0x0007fd02)) { > dev_err(&pdev->dev, "ARC EMAC not detected, id=3D0x%x\n", id); > err =3D -ENODEV; > - goto out_netdev; > + goto out_clken; > } > dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id); >=20 > @@ -708,7 +720,7 @@ static int arc_emac_probe(struct platform_device = *pdev) > ndev->name, ndev); > if (err) { > dev_err(&pdev->dev, "could not allocate IRQ\n"); > - goto out_netdev; > + goto out_clken; > } >=20 > /* Get MAC address from device tree */ > @@ -729,7 +741,7 @@ static int arc_emac_probe(struct platform_device = *pdev) > if (!priv->rxbd) { > dev_err(&pdev->dev, "failed to allocate data buffers\n"); > err =3D -ENOMEM; > - goto out_netdev; > + goto out_clken; > } >=20 > priv->txbd =3D priv->rxbd + RX_BD_NUM; > @@ -741,7 +753,7 @@ static int arc_emac_probe(struct platform_device = *pdev) > err =3D arc_mdio_probe(pdev, priv); > if (err) { > dev_err(&pdev->dev, "failed to probe MII bus\n"); > - goto out_netdev; > + goto out_clken; > } >=20 > priv->phy_dev =3D of_phy_connect(ndev, phy_node, arc_emac_adjust_li= nk, 0, > @@ -772,6 +784,12 @@ out_netif_api: > priv->phy_dev =3D NULL; > out_mdio: > arc_mdio_remove(priv); > +out_clken: > + if (IS_ERR(priv->clk)) > + clk_disable_unprepare(priv->clk); Should be if (!IS_ERR(priv->clk)). > +out_clkget: > + if (IS_ERR(priv->clk)) > + clk_put(priv->clk); The same. > out_netdev: > free_netdev(ndev); > return err; > @@ -787,6 +805,12 @@ static int arc_emac_remove(struct platform_devic= e > *pdev) arc_mdio_remove(priv); > unregister_netdev(ndev); > netif_napi_del(&priv->napi); > + > + if (!IS_ERR(priv->clk)) { > + clk_disable_unprepare(priv->clk); > + clk_put(priv->clk); > + } > + > free_netdev(ndev); >=20 > return 0; Apart from that, the clock stuff has been Tested-by: Max Schwarz (on the same hardware, radxa rock) Cheers, Max