target/linux/generic/backport-6.6/790-21-v6.9-net-dsa-mt7530-do-not-use-SW_PHY_RST-to-reset-MT7531.patch

   1 From 80f4f866d7dad41b12cf37476c38766a89b8b5c4 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Ar=C4=B1n=C3=A7=20=C3=9CNAL?= <arinc.unal@arinc9.com>
   3 Date: Fri, 1 Mar 2024 12:42:59 +0200
   4 Subject: [PATCH 21/30] net: dsa: mt7530: do not use SW_PHY_RST to reset MT7531
   5  switch
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 According to the document MT7531 Reference Manual for Development Board
  11 v1.0, the SW_PHY_RST bit on the SYS_CTRL register doesn't exist for
  12 MT7531. This is likely why forcing link down on all ports is necessary for
  13 MT7531.
  14
  15 Therefore, do not set SW_PHY_RST on mt7531_setup().
  16
  17 Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
  18 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
  19 ---
  20  drivers/net/dsa/mt7530.c | 6 ++----
  21  1 file changed, 2 insertions(+), 4 deletions(-)
  22
  23 --- a/drivers/net/dsa/mt7530.c
  24 +++ b/drivers/net/dsa/mt7530.c
  25 @@ -2487,14 +2487,12 @@ mt7531_setup(struct dsa_switch *ds)
  26         val = mt7530_read(priv, MT7531_TOP_SIG_SR);
  27         priv->p5_sgmii = !!(val & PAD_DUAL_SGMII_EN);
  28
  29 -       /* all MACs must be forced link-down before sw reset */
  30 +       /* Force link down on all ports before internal reset */
  31         for (i = 0; i < MT7530_NUM_PORTS; i++)
  32                 mt7530_write(priv, MT7530_PMCR_P(i), MT7531_FORCE_LNK);
  33
  34         /* Reset the switch through internal reset */
  35 -       mt7530_write(priv, MT7530_SYS_CTRL,
  36 -                    SYS_CTRL_PHY_RST | SYS_CTRL_SW_RST |
  37 -                    SYS_CTRL_REG_RST);
  38 +       mt7530_write(priv, MT7530_SYS_CTRL, SYS_CTRL_SW_RST | SYS_CTRL_REG_RST);
  39
  40         if (!priv->p5_sgmii) {
  41                 mt7531_pll_setup(priv);