From 728c2af6ad8c809f66639b70e4fd8c67c57c66e7 Mon Sep 17 00:00:00 2001 From: Alexander Couzens Date: Sat, 17 Sep 2022 02:07:34 +0200 Subject: [PATCH] net: mt7531: ensure all MACs are powered down before reset The datasheet [1] explicit describes it as requirement for a reset. [1] MT7531 Reference Manual for Development Board rev 1.0, page 735 Signed-off-by: Alexander Couzens Signed-off-by: Jakub Kicinski --- drivers/net/dsa/mt7530.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/dsa/mt7530.c b/drivers/net/dsa/mt7530.c index 95a57aeb466e9..409d5c3d76ea6 100644 --- a/drivers/net/dsa/mt7530.c +++ b/drivers/net/dsa/mt7530.c @@ -2329,6 +2329,10 @@ mt7531_setup(struct dsa_switch *ds) return -ENODEV; } + /* all MACs must be forced link-down before sw reset */ + for (i = 0; i < MT7530_NUM_PORTS; i++) + mt7530_write(priv, MT7530_PMCR_P(i), MT7531_FORCE_LNK); + /* Reset the switch through internal reset */ mt7530_write(priv, MT7530_SYS_CTRL, SYS_CTRL_PHY_RST | SYS_CTRL_SW_RST | -- 2.30.2