net: cadence: macb: enable EEE for Raspberry Pi RP1

Set MACB_CAPS_EEE for the Raspberry Pi 5 RP1 southbridge
(Cadence GEM_GXL rev 0x00070109 paired with BCM54213PE PHY).

EEE has been verified on RP1 hardware: the LPI counter registers
at 0x270-0x27c return valid data, the TXLPIEN bit in NCR (bit 19)
controls LPI transmission correctly, and ethtool --show-eee reports
the negotiated state after link-up.

Other GEM variants that share the same LPI register layout (SAMA5D2,
SAME70, PIC32CZ) can be enabled by adding MACB_CAPS_EEE to their
respective config entries once tested.

Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Reviewed-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Nicolai Buchwitz <nb@tipi-net.de>
Link: https://patch.msgid.link/20260304105432.631186-5-nb@tipi-net.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index f01366394cff79ec1b7d3e069df2ff4d0c10aaa9..5933a5042bc81e456d057db0b515d95f32c04428 100644 (file)
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5537,7 +5537,8 @@ static const struct macb_config eyeq5_config = {
 static const struct macb_config raspberrypi_rp1_config = {
        .caps = MACB_CAPS_GIGABIT_MODE_AVAILABLE | MACB_CAPS_CLK_HW_CHG |
                MACB_CAPS_JUMBO |
-               MACB_CAPS_GEM_HAS_PTP,
+               MACB_CAPS_GEM_HAS_PTP |
+               MACB_CAPS_EEE,
        .dma_burst_length = 16,
        .clk_init = macb_clk_init,
        .init = macb_init,