Hi Niklas,
On Mon, Nov 28, 2016 at 12:46 PM, Niklas Söderlund
<niklas.soderlund+renesas@xxxxxxxxxxxx> wrote:
> The EthernetAVB should not depend on the bootloader to setup correct
> drive-strength values. Values for drive-strength where found by examine
examining
> the registers after the bootloader have configured the registers and
has
> successfully used the EthernetAVB.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> ---
> arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts | 28 ++++++++++++++++++++--
> 1 file changed, 26 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts b/arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts
> index b1eab68..7f49d19 100644
> --- a/arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts
> +++ b/arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts
> @@ -225,8 +225,32 @@
> };
>
> avb_pins: avb {
> - groups = "avb_mdc";
> - function = "avb";
> + mux {
> + groups = "avb_mdc", "avb_mii";
> + function = "avb";
> + };
> +
> + pins_mdc {
> + groups = "avb_mdc";
> + drive-strength = <24>;
> + };
> +
> + pins_mii_tx {
> + pins = "PIN_AVB_TX_CTL", "PIN_AVB_TXC", "PIN_AVB_TD0",
> + "PIN_AVB_TD1", "PIN_AVB_TD2", "PIN_AVB_TD3";
> + drive-strength = <12>;
> + };
> +
> + pins_mii_rx {
> + pins = "PIN_AVB_RX_CTL", "PIN_AVB_RXC", "PIN_AVB_RD0",
> + "PIN_AVB_RD1", "PIN_AVB_RD2", "PIN_AVB_RD3";
> + drive-strength = <24>;
> + };
> +
> + pins_mii_clk {
> + pins = "PIN_AVB_TXCREFCLK";
> + drive-strength = <24>;
> + };
> };
>
> du_pins: du {
What about AVB_PHY_INT and AVB_LINK?
Or don't you need to specify their drive strengths, as they are input signals?
Then what about pins_mii_rx, they're also input signals?
BTW, the latest public U-Boot seems to configure just AVB_TX_CTL, AVB_TXC,
and AVB_TXD[0-3] for 12 mA, cfr.
https://github.com/renesas-rcar/u-boot/blob/v2015.04/rcar-3.4.0/board/renesas/salvator-x/salvator-x.c#L158
According to the datasheet, the reset values of all signals are 15 mA on H3 ES1,
and 24 mA on M3-W and H3 ES2.0.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
