[PATCH can-next v2 10/20] can: rockchip_canfd: rkcanfd_register_done(): add warning for erratum 5

[Marc Kleine-Budde]

Tests on the rk3568v2 and rk3568v3 show that a reduced "baudclk" (e.g.
80MHz, compared to the standard 300MHz) significantly increases the
possibility of incorrect FIFO counters, i.e. erratum 5.

Print an info message if the clock is below the known good value of
300MHz.

Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
---
 drivers/net/can/rockchip/rockchip_canfd-core.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/can/rockchip/rockchip_canfd-core.c b/drivers/net/can/rockchip/rockchip_canfd-core.c
index 7b4abf9984af..232bc49b1a48 100644
--- a/drivers/net/can/rockchip/rockchip_canfd-core.c
+++ b/drivers/net/can/rockchip/rockchip_canfd-core.c
@@ -738,6 +738,13 @@ static void rkcanfd_register_done(const struct rkcanfd_priv *priv)
 		    FIELD_GET(RKCANFD_REG_RTL_VERSION_MAJOR, dev_id),
 		    FIELD_GET(RKCANFD_REG_RTL_VERSION_MINOR, dev_id),
 		    priv->devtype_data.quirks);
+
+	if (priv->devtype_data.quirks & RKCANFD_QUIRK_RK3568_ERRATUM_5 &&
+	    priv->can.clock.freq < RKCANFD_ERRATUM_5_SYSCLOCK_HZ_MIN)
+		netdev_info(priv->ndev,
+			    "Erratum 5: CAN clock frequency (%luMHz) lower than known good (%luMHz), expect degraded performance\n",
+			    priv->can.clock.freq / MEGA,
+			    RKCANFD_ERRATUM_5_SYSCLOCK_HZ_MIN / MEGA);
 }
 
 static int rkcanfd_register(struct rkcanfd_priv *priv)

-- 
2.43.0