net: ti: cpsw: enable 10Mbps link speed support in rgmii mode

According to TRMs the 10Mbps link speed is supported in RGMII only when
CPSW2G MAC SL is configured for External Control ("in band") mode
CPSW_SL_MACCTRL.EXT_EN(18) = 1.

Hence update cpsw_slave_update_link() to follow documentation.

[1] https://patchwork.kernel.org/patch/10285239/
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>

diff --git a/drivers/net/ti/cpsw.c b/drivers/net/ti/cpsw.c
index 20ddb44..f0d008f 100644 (file)
--- a/drivers/net/ti/cpsw.c
+++ b/drivers/net/ti/cpsw.c
@@ -33,6 +33,7 @@ DECLARE_GLOBAL_DATA_PTR;
 #define GIGABITEN              BIT(7)
 #define FULLDUPLEXEN           BIT(0)
 #define MIIEN                  BIT(15)
+#define CTL_EXT_EN             BIT(18)
 /* DMA Registers */
 #define CPDMA_TXCONTROL                0x004
 #define CPDMA_RXCONTROL                0x014
@@ -489,6 +490,8 @@ static int cpsw_slave_update_link(struct cpsw_slave *slave,
                        mac_control |= FULLDUPLEXEN;
                if (phy->speed == 100)
                        mac_control |= MIIEN;
+               if (phy->speed == 10 && phy_interface_is_rgmii(phy))
+                       mac_control |= CTL_EXT_EN;
        }
 
        if (mac_control == slave->mac_control)