[PATCH v3 4/8] net: stmmac: dwmac-meson8b: Move the documentation for the TX delay
From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date: 2020-05-12 21:11:54
Also in:
linux-amlogic, linux-arm-kernel, linux-devicetree, lkml
Subsystem:
networking drivers, stmmac ethernet driver, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Maxime Chevallier, Linus Torvalds
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 <andrew@lunn.ch> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> --- drivers/net/ethernet/stmicro/stmmac/dwmac-meson8b.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
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 */
--
2.26.2