From 889df20305ffeae0a6bbd435761810ba658e223d Mon Sep 17 00:00:00 2001 From: Martin Blumenstingl Date: Tue, 12 May 2020 23:10:59 +0200 Subject: net: stmmac: dwmac-meson8b: Move the documentation for the TX delay Move the documentation for the TX delay above the PRG_ETH0_TXDLY_MASK definition. Future commits will add more registers also with documentation above their register bit definitions. Move the existing comment so it will be consistent with the upcoming changes. Reviewed-by: Andrew Lunn Signed-off-by: Martin Blumenstingl Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c') diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c index c9ec0cb68082..1d7526ee09dd 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c @@ -33,6 +33,10 @@ #define PRG_ETH0_CLK_M250_SEL_SHIFT 4 #define PRG_ETH0_CLK_M250_SEL_MASK GENMASK(4, 4) +/* TX clock delay in ns = "8ns / 4 * tx_dly_val" (where 8ns are exactly one + * cycle of the 125MHz RGMII TX clock): + * 0ns = 0x0, 2ns = 0x1, 4ns = 0x2, 6ns = 0x3 + */ #define PRG_ETH0_TXDLY_MASK GENMASK(6, 5) /* divider for the result of m250_sel */ @@ -248,10 +252,6 @@ static int meson8b_init_prg_eth(struct meson8b_dwmac *dwmac) switch (dwmac->phy_mode) { case PHY_INTERFACE_MODE_RGMII: case PHY_INTERFACE_MODE_RGMII_RXID: - /* TX clock delay in ns = "8ns / 4 * tx_dly_val" (where - * 8ns are exactly one cycle of the 125MHz RGMII TX clock): - * 0ns = 0x0, 2ns = 0x1, 4ns = 0x2, 6ns = 0x3 - */ tx_dly_val = dwmac->tx_delay_ns >> 1; /* fall through */ -- cgit v1.2.3