net: stmmac: Add platform level debug register dump feature

dwmac-qcom-ethqos currently exposes a mechanism to dump rgmii registers
after the 'stmmac_dvr_probe()' returns. However with commit
5ec55823438e ("net: stmmac: add clocks management for gmac driver"),
we now let 'pm_runtime_put()' disable the clocks before returning from
'stmmac_dvr_probe()'.

This causes a crash when 'rgmii_dump()' register dumps are enabled,
as the clocks are already off.

Since other dwmac drivers (possible future users as well) might
require a similar register dump feature, introduce a platform level
callback to allow the same.

This fixes the crash noticed while enabling rgmii_dump() dumps in
dwmac-qcom-ethqos driver as well. It also allows future changes
to keep a invoking the register dump callback from the correct
place inside 'stmmac_dvr_probe()'.

Fixes: 5ec55823438e ("net: stmmac: add clocks management for gmac driver")
Cc: Joakim Zhang <qiangqing.zhang@nxp.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index 8fea48e..2ffa0a1 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -113,8 +113,10 @@ static void rgmii_updatel(struct qcom_ethqos *ethqos,
        rgmii_writel(ethqos, temp, offset);
 }
 
-static void rgmii_dump(struct qcom_ethqos *ethqos)
+static void rgmii_dump(void *priv)
 {
+       struct qcom_ethqos *ethqos = priv;
+
        dev_dbg(&ethqos->pdev->dev, "Rgmii register dump\n");
        dev_dbg(&ethqos->pdev->dev, "RGMII_IO_MACRO_CONFIG: %x\n",
                rgmii_readl(ethqos, RGMII_IO_MACRO_CONFIG));
@@ -519,6 +521,7 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
 
        plat_dat->bsp_priv = ethqos;
        plat_dat->fix_mac_speed = ethqos_fix_mac_speed;
+       plat_dat->dump_debug_regs = rgmii_dump;
        plat_dat->has_gmac4 = 1;
        plat_dat->pmt = 1;
        plat_dat->tso_en = of_property_read_bool(np, "snps,tso");
@@ -527,8 +530,6 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
        if (ret)
                goto err_clk;
 
-       rgmii_dump(ethqos);
-
        return ret;
 
 err_clk:

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 89a6c35..cc1075c 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -7211,6 +7211,9 @@ int stmmac_dvr_probe(struct device *device,
        stmmac_init_fs(ndev);
 #endif
 
+       if (priv->plat->dump_debug_regs)
+               priv->plat->dump_debug_regs(priv->plat->bsp_priv);
+
        /* Let pm_runtime_put() disable the clocks.
         * If CONFIG_PM is not enabled, the clocks will stay powered.
         */

diff --git a/include/linux/stmmac.h b/include/linux/stmmac.h
index 89b8e20..24eea1b 100644 (file)
--- a/include/linux/stmmac.h
+++ b/include/linux/stmmac.h
@@ -233,6 +233,7 @@ struct plat_stmmacenet_data {
        int (*clks_config)(void *priv, bool enabled);
        int (*crosststamp)(ktime_t *device, struct system_counterval_t *system,
                           void *ctx);
+       void (*dump_debug_regs)(void *priv);
        void *bsp_priv;
        struct clk *stmmac_clk;
        struct clk *pclk;