Re: [PATCH] net: stmmac: Add OXNAS Glue Driver
From: Giuseppe CAVALLARO
Date: Fri Oct 21 2016 - 07:53:58 EST
Hello
some my minor cents below
On 10/21/2016 12:20 PM, Joachim Eastwood wrote:
Hi Neil,
On 21 October 2016 at 10:44, Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
Add Synopsys Designware MAC Glue layer for the Oxford Semiconductor OX820.
Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
---
.../devicetree/bindings/net/oxnas-dwmac.txt | 44 +++++
drivers/net/ethernet/stmicro/stmmac/Kconfig | 11 ++
drivers/net/ethernet/stmicro/stmmac/Makefile | 1 +
drivers/net/ethernet/stmicro/stmmac/dwmac-oxnas.c | 219 +++++++++++++++++++++
4 files changed, 275 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/oxnas-dwmac.txt
create mode 100644 drivers/net/ethernet/stmicro/stmmac/dwmac-oxnas.c
Changes since RFC at https://patchwork.kernel.org/patch/9387257 :
- Drop init/exit callbacks
- Implement proper remove and PM callback
- Call init from probe
- Disable/Unprepare clock if stmmac probe fails
<snip>
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-oxnas.c
@@ -0,0 +1,219 @@
+/*
+ * Oxford Semiconductor OXNAS DWMAC glue layer
+ *
+ * Copyright (C) 2016 Neil Armstrong <narmstrong@xxxxxxxxxxxx>
+ * Copyright (C) 2014 Daniel Golle <daniel@xxxxxxxxxxxxxx>
+ * Copyright (C) 2013 Ma Haijun <mahaijuns@xxxxxxxxx>
+ * Copyright (C) 2012 John Crispin <blogic@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/stmmac.h>
+
+#include "stmmac_platform.h"
+
+/* System Control regmap offsets */
+#define OXNAS_DWMAC_CTRL_REGOFFSET 0x78
+#define OXNAS_DWMAC_DELAY_REGOFFSET 0x100
+
+/* Control Register */
+#define DWMAC_CKEN_RX_IN 14
+#define DWMAC_CKEN_RXN_OUT 13
+#define DWMAC_CKEN_RX_OUT 12
+#define DWMAC_CKEN_TX_IN 10
+#define DWMAC_CKEN_TXN_OUT 9
+#define DWMAC_CKEN_TX_OUT 8
+#define DWMAC_RX_SOURCE 7
+#define DWMAC_TX_SOURCE 6
+#define DWMAC_LOW_TX_SOURCE 4
+#define DWMAC_AUTO_TX_SOURCE 3
+#define DWMAC_RGMII 2
+#define DWMAC_SIMPLE_MUX 1
+#define DWMAC_CKEN_GTX 0
+
+/* Delay register */
+#define DWMAC_TX_VARDELAY_SHIFT 0
+#define DWMAC_TXN_VARDELAY_SHIFT 8
+#define DWMAC_RX_VARDELAY_SHIFT 16
+#define DWMAC_RXN_VARDELAY_SHIFT 24
+#define DWMAC_TX_VARDELAY(d) ((d) << DWMAC_TX_VARDELAY_SHIFT)
+#define DWMAC_TXN_VARDELAY(d) ((d) << DWMAC_TXN_VARDELAY_SHIFT)
+#define DWMAC_RX_VARDELAY(d) ((d) << DWMAC_RX_VARDELAY_SHIFT)
+#define DWMAC_RXN_VARDELAY(d) ((d) << DWMAC_RXN_VARDELAY_SHIFT)
+
+struct oxnas_dwmac {
+ struct device *dev;
+ struct clk *clk;
+ struct regmap *regmap;
+};
+
+static int oxnas_dwmac_init(struct oxnas_dwmac *dwmac)
+{
+ unsigned int value;
+ int ret;
+
+ /* Reset HW here before changing the glue configuration */
+ ret = device_reset(dwmac->dev);
+ if (ret)
+ return ret;
+
+ clk_prepare_enable(dwmac->clk);
You might want to check the return value from clk_prepare_enable() as well.
+
+ ret = regmap_read(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, &value);
+ if (ret < 0)
+ return ret;
+
+ /* Enable GMII_GTXCLK to follow GMII_REFCLK, required for gigabit PHY */
+ value |= BIT(DWMAC_CKEN_GTX);
+ /* Use simple mux for 25/125 Mhz clock switching */
+ value |= BIT(DWMAC_SIMPLE_MUX);
+ /* set auto switch tx clock source */
+ value |= BIT(DWMAC_AUTO_TX_SOURCE);
+ /* enable tx & rx vardelay */
+ value |= BIT(DWMAC_CKEN_TX_OUT);
+ value |= BIT(DWMAC_CKEN_TXN_OUT);
+ value |= BIT(DWMAC_CKEN_TX_IN);
+ value |= BIT(DWMAC_CKEN_RX_OUT);
+ value |= BIT(DWMAC_CKEN_RXN_OUT);
+ value |= BIT(DWMAC_CKEN_RX_IN);
+ regmap_write(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, value);
+
+ /* set tx & rx vardelay */
+ value = DWMAC_TX_VARDELAY(4);
+ value |= DWMAC_TXN_VARDELAY(2);
+ value |= DWMAC_RX_VARDELAY(10);
+ value |= DWMAC_RXN_VARDELAY(8);
+ regmap_write(dwmac->regmap, OXNAS_DWMAC_DELAY_REGOFFSET, value);
there is no if condition so, I can suggest you, to hardwire
value with macros instead of computing at runtime:
e.g.
var = DWMAC_VARDELAY where
#define DWMAC_VARDELAY (DWMAC_TX_VARDELAY(4) | ...)
... same for OXNAS_DWMAC_CTRL_REGOFFSET where
BIT(DWMAC_CKEN_ ... ) should be re-organized as macros,
I mean:
#define DWMAC_CKEN_.. BIT(xxx)
+
+ return 0;
+}
+
+static int oxnas_dwmac_probe(struct platform_device *pdev)
+{
+ struct plat_stmmacenet_data *plat_dat;
+ struct stmmac_resources stmmac_res;
+ struct device_node *sysctrl;
+ struct oxnas_dwmac *dwmac;
+ int ret;
+
+ sysctrl = of_parse_phandle(pdev->dev.of_node, "oxsemi,sys-ctrl", 0);
+ if (!sysctrl) {
+ dev_err(&pdev->dev, "failed to get sys-ctrl node\n");
+ return -EINVAL;
+ }
+
+ ret = stmmac_get_platform_resources(pdev, &stmmac_res);
+ if (ret)
+ return ret;
+
+ plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
+ if (IS_ERR(plat_dat))
+ return PTR_ERR(plat_dat);
+
+ dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
+ if (!dwmac)
+ return -ENOMEM;
+
+ dwmac->dev = &pdev->dev;
+ plat_dat->bsp_priv = dwmac;
+
+ dwmac->regmap = syscon_node_to_regmap(sysctrl);
+ if (IS_ERR(dwmac->regmap)) {
+ dev_err(&pdev->dev, "failed to have sysctrl regmap\n");
+ return PTR_ERR(dwmac->regmap);
+ }
+
+ dwmac->clk = devm_clk_get(&pdev->dev, "gmac");
+ if (IS_ERR(dwmac->clk))
+ return PTR_ERR(dwmac->clk);
+
+ ret = oxnas_dwmac_init(dwmac);
+ if (ret)
+ return ret;
+
+ ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
+ if (ret)
+ clk_disable_unprepare(dwmac->clk);
+
+ return ret;
+}
+
+static int oxnas_dwmac_remove(struct platform_device *pdev)
+{
+ struct net_device *ndev = platform_get_drvdata(pdev);
+ struct stmmac_priv *priv = netdev_priv(ndev);
+ struct oxnas_dwmac *dwmac = priv->plat->bsp_priv;
Instead of this long dance of variables use the get_stmmac_bsp_priv()-helper.
You can take a look at dwmac-meson8b.c for reference.
+ int ret = stmmac_dvr_remove(&pdev->dev);
+
+ clk_disable_unprepare(dwmac->clk);
+
+ return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int oxnas_dwmac_suspend(struct device *dev)
+{
+ struct net_device *ndev = dev_get_drvdata(dev);
+ struct stmmac_priv *priv = netdev_priv(ndev);
+ struct oxnas_dwmac *dwmac = priv->plat->bsp_priv;
get_stmmac_bsp_priv()
+ int ret;
+
+ ret = stmmac_suspend(dev);
+ clk_disable_unprepare(dwmac->clk);
+
+ return ret;
+}
+
+static int oxnas_dwmac_resume(struct device *dev)
+{
+ struct net_device *ndev = dev_get_drvdata(dev);
+ struct stmmac_priv *priv = netdev_priv(ndev);
+ struct oxnas_dwmac *dwmac = priv->plat->bsp_priv;
get_stmmac_bsp_priv()
+ int ret;
+
+ ret = oxnas_dwmac_init(dwmac);
+ if (ret)
+ return ret;
+
+ ret = stmmac_resume(dev);
+
+ return ret;
+}
+#endif /* CONFIG_PM_SLEEP */
With these changes:
Acked-by: Joachim Eastwood <manabian@xxxxxxxxx>
best regards,
Joachim Eastwood