From: Heiko Stübner Date: Fri, 25 Apr 2014 08:06:13 +0000 (+0200) Subject: arc_emac: add clock handling X-Git-Tag: v4.9.8~6428^2~34 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=88154c96ee2dab84ae78ad41562b4a3a23d83788;p=platform%2Fkernel%2Flinux-rpi3.git arc_emac: add clock handling This adds ability for the arc_emac to really handle its supplying clock. To get the needed clock-frequency either a real clock or the previous clock-frequency property must be provided. Signed-off-by: Heiko Stuebner Tested-by: Max Schwarz Signed-off-by: David S. Miller --- diff --git a/Documentation/devicetree/bindings/net/arc_emac.txt b/Documentation/devicetree/bindings/net/arc_emac.txt index 7fbb027..a1d71eb 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. +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 to the MDIO bus. They must have a "reg" property given the PHY address on the MDIO bus. @@ -19,7 +23,11 @@ Examples: reg = <0xc0fc2000 0x3c>; interrupts = <6>; mac-address = [ 00 11 22 33 44 55 ]; + clock-frequency = <80000000>; + /* or */ + clocks = <&emac_clock>; + max-speed = <100>; phy = <&phy0>; 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 /* 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; void __iomem *regs; + struct clk *clk; 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 9747dda..d647a7d 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; } - /* 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 device tree\n"); - return -EINVAL; - } - /* Get IRQ from device tree */ irq = irq_of_parse_and_map(pdev->dev.of_node, 0); if (!irq) { @@ -687,13 +680,32 @@ static int arc_emac_probe(struct platform_device *pdev) } dev_dbg(&pdev->dev, "Registers base address is 0x%p\n", priv->regs); + priv->clk = 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 device tree\n"); + err = -EINVAL; + goto out_netdev; + } + } else { + err = clk_prepare_enable(priv->clk); + if (err) { + dev_err(&pdev->dev, "failed to enable clock\n"); + goto out_clkget; + } + + clock_frequency = clk_get_rate(priv->clk); + } + id = arc_reg_get(priv, R_ID); /* Check for EMAC revision 5 or 7, magic number */ if (!(id == 0x0005fd02 || id == 0x0007fd02)) { dev_err(&pdev->dev, "ARC EMAC not detected, id=0x%x\n", id); err = -ENODEV; - goto out_netdev; + goto out_clken; } dev_info(&pdev->dev, "ARC EMAC detected with id: 0x%x\n", id); @@ -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; } /* 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 = -ENOMEM; - goto out_netdev; + goto out_clken; } priv->txbd = priv->rxbd + RX_BD_NUM; @@ -741,7 +753,7 @@ static int arc_emac_probe(struct platform_device *pdev) err = arc_mdio_probe(pdev, priv); if (err) { dev_err(&pdev->dev, "failed to probe MII bus\n"); - goto out_netdev; + goto out_clken; } priv->phy_dev = of_phy_connect(ndev, phy_node, arc_emac_adjust_link, 0, @@ -771,6 +783,12 @@ out_netif_api: priv->phy_dev = NULL; out_mdio: arc_mdio_remove(priv); +out_clken: + if (!IS_ERR(priv->clk)) + clk_disable_unprepare(priv->clk); +out_clkget: + if (!IS_ERR(priv->clk)) + clk_put(priv->clk); out_netdev: free_netdev(ndev); return err; @@ -786,6 +804,12 @@ static int arc_emac_remove(struct platform_device *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); return 0;