net: stmmac: dwmac-renesas-gbeth: Add support for RZ/T2H SoC

Extend the Renesas GBETH stmmac glue driver to support the RZ/T2H SoC,
where the GMAC is connected through a MIIC PCS. Introduce a new
`has_pcs` flag in `struct renesas_gbeth_of_data` to indicate when PCS
handling is required.

When enabled, the driver parses the `pcs-handle` phandle, creates a PCS
instance with `miic_create()`, and wires it into phylink. Proper cleanup
is done with `miic_destroy()`. New init/exit/select hooks are added to
`plat_stmmacenet_data` for PCS integration.

Update Kconfig to select `PCS_RZN1_MIIC` when building the Renesas GBETH
driver so the PCS support is always available.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://patch.msgid.link/20250908105901.3198975-4-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/stmicro/stmmac/Kconfig b/drivers/net/ethernet/stmicro/stmmac/Kconfig
index 67fa879b1e521ef6d7bd2a8db30d812301eb4cf7..91d9a14362bf68a1b4a883d6346fa7ee6d5cefca 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/Kconfig
+++ b/drivers/net/ethernet/stmicro/stmmac/Kconfig
@@ -133,15 +133,17 @@ config DWMAC_QCOM_ETHQOS
          stmmac device driver.
 
 config DWMAC_RENESAS_GBETH
-       tristate "Renesas RZ/V2H(P) GBETH support"
+       tristate "Renesas RZ/V2H(P) GBETH and RZ/T2H, RZ/N2H GMAC support"
        default ARCH_RENESAS
        depends on OF && (ARCH_RENESAS || COMPILE_TEST)
+       select PCS_RZN1_MIIC
        help
-         Support for Gigabit Ethernet Interface (GBETH) on Renesas
-         RZ/V2H(P) SoCs.
+         Support for Gigabit Ethernet Interface (GBETH)/ Ethernet MAC (GMAC)
+         on Renesas SoCs.
 
-         This selects the Renesas RZ/V2H(P) Soc specific glue layer support
-         for the stmmac device driver.
+         This selects Renesas SoC glue layer support for the stmmac device
+         driver. This driver is used for the RZ/V2H(P) family, RZ/T2H and
+         RZ/N2H SoCs.
 
 config DWMAC_ROCKCHIP
        tristate "Rockchip dwmac support"

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c
index 50be944ee37bf24109cebb03b259ef2163d28773..bc7bb975803ca08f71f97c2f4bea5d367a89a83b 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-renesas-gbeth.c
@@ -17,6 +17,7 @@
 #include <linux/device.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/pcs-rzn1-miic.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>
 #include <linux/types.h>
@@ -33,6 +34,7 @@
  *                handled by the glue driver or core driver.
  * @set_clk_tx_rate: Flag to indicate if Tx clock is fixed or
  *                   set_clk_tx_rate is needed.
+ * @has_pcs: Flag to indicate if the MAC has a PCS
  */
 struct renesas_gbeth_of_data {
        const char * const *clks;
@@ -40,6 +42,7 @@ struct renesas_gbeth_of_data {
        u32 stmmac_flags;
        bool handle_reset;
        bool set_clk_tx_rate;
+       bool has_pcs;
 };
 
 struct renesas_gbeth {
@@ -53,6 +56,41 @@ static const char *const renesas_gbeth_clks[] = {
        "tx", "tx-180", "rx", "rx-180",
 };
 
+static const char *const renesas_gmac_clks[] = {
+       "tx",
+};
+
+static int renesas_gmac_pcs_init(struct stmmac_priv *priv)
+{
+       struct device_node *np = priv->device->of_node;
+       struct device_node *pcs_node;
+       struct phylink_pcs *pcs;
+
+       pcs_node = of_parse_phandle(np, "pcs-handle", 0);
+       if (pcs_node) {
+               pcs = miic_create(priv->device, pcs_node);
+               of_node_put(pcs_node);
+               if (IS_ERR(pcs))
+                       return PTR_ERR(pcs);
+
+               priv->hw->phylink_pcs = pcs;
+       }
+
+       return 0;
+}
+
+static void renesas_gmac_pcs_exit(struct stmmac_priv *priv)
+{
+       if (priv->hw->phylink_pcs)
+               miic_destroy(priv->hw->phylink_pcs);
+}
+
+static struct phylink_pcs *renesas_gmac_select_pcs(struct stmmac_priv *priv,
+                                                  phy_interface_t interface)
+{
+       return priv->hw->phylink_pcs;
+}
+
 static int renesas_gbeth_init(struct platform_device *pdev, void *priv)
 {
        struct plat_stmmacenet_data *plat_dat;
@@ -150,6 +188,11 @@ static int renesas_gbeth_probe(struct platform_device *pdev)
        plat_dat->exit = renesas_gbeth_exit;
        plat_dat->flags |= STMMAC_FLAG_EN_TX_LPI_CLK_PHY_CAP |
                           gbeth->of_data->stmmac_flags;
+       if (of_data->has_pcs) {
+               plat_dat->pcs_init = renesas_gmac_pcs_init;
+               plat_dat->pcs_exit = renesas_gmac_pcs_exit;
+               plat_dat->select_pcs = renesas_gmac_select_pcs;
+       }
 
        return devm_stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
 }
@@ -163,7 +206,15 @@ static const struct renesas_gbeth_of_data renesas_gbeth_of_data = {
                        STMMAC_FLAG_SPH_DISABLE,
 };
 
+static const struct renesas_gbeth_of_data renesas_gmac_of_data = {
+       .clks = renesas_gmac_clks,
+       .num_clks = ARRAY_SIZE(renesas_gmac_clks),
+       .stmmac_flags = STMMAC_FLAG_HWTSTAMP_CORRECT_LATENCY,
+       .has_pcs = true,
+};
+
 static const struct of_device_id renesas_gbeth_match[] = {
+       { .compatible = "renesas,r9a09g077-gbeth", .data = &renesas_gmac_of_data },
        { .compatible = "renesas,rzv2h-gbeth", .data = &renesas_gbeth_of_data },
        { /* Sentinel */ }
 };