On 05/30/2017 03:08 PM, Leonard Crestez wrote:

On Tue, 2017-05-30 at 11:05 -0700, Florian Fainelli wrote:

quoted

On 05/30/2017 10:34 AM, Leonard Crestez wrote:

quoted

These bits seem to be lost after a suspend/resume cycle so just set them
again.

This patch fixes ethernet suspend/resume on imx6ul-14x14-evk boards.

Signed-off-by: Leonard Crestez <redacted>
---
 drivers/net/phy/micrel.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 6a5fd18..c53ee17 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c

@@ -700,6 +700,9 @@ static int kszphy_suspend(struct phy_device *phydev)
 
 static int kszphy_resume(struct phy_device *phydev)
 {
+	struct kszphy_priv *priv = phydev->priv;
+	int ret;
+
 	genphy_resume(phydev);
 
 	/* Enable PHY Interrupts */

@@ -709,6 +712,18 @@ static int kszphy_resume(struct phy_device *phydev)
 			phydev->drv->config_intr(phydev);
 	}
 
+	if (priv->rmii_ref_clk_sel) {
+		ret = kszphy_rmii_clk_sel(phydev, priv->rmii_ref_clk_sel_val);
+		if (ret) {
+			phydev_err(phydev,
+				   "failed to set rmii reference clock\n");
+			return ret;
+		}
+	}
+
+	if (priv->led_mode >= 0)
+		kszphy_setup_led(phydev, priv->type->led_mode_reg, priv->led_mode);

Should not we actually call kszphy_config_init() in order to restore
broadcast and nand disable bits as well?

I don't know. In my case the B_CAST_OFF bit doesn't seem to be lost and
NAND_TREE_ON is already off by the time it gets to linux.

The bit that get lost seem to disappear just as the phy is resumed. I
added some prints and they look like this:

PM: early resume of devices complete after 6.534 msecs
begin resume
0x1F=0x8190 0x16=0x202
after genphy_resume 0x1F=0x8100 0x16=0x202
end
resume 0x1F=0x8190 0x16=0x202

OK, so it actually would not hurt to call config_init() again here, right?

quoted

If not, I would be more comfortable if we did create a specific function
that takes care of setting the reference clock and LED mode.

Ok, I can add a function called kszphy_config_reset() with a comment
explaining it's for bits lost on reset/resume.

Or perhaps a better option would be to just save/restore the entire
0x1F register?

Register 0 through 15 are standardized, but those after that are not,
and PHYs with a gazillion of registers already need to have a specific
set of suspend/resume sequence due to their proprietary indirect
register scheme, so we cannot quite come up with a generic function that
would cache all 16 or 32 registers and flat out restore those.

Similarly, having phy_resume() systematically calling into config_init()
is a bit of a stretch and can be pretty inefficient.
-- 
Florian