On Mon, May 17, 2021 at 11:37:12AM +0000, Sit, Michael Wei Hong wrote:

quoted

From: Russell King <linux@armlinux.org.uk>

On Mon, May 17, 2021 at 05:43:32PM +0800, Michael Sit Wei Hong
wrote:

quoted

Link xpcs callback functions for MAC to configure the xpcs EEE

feature.

quoted

The clk_eee frequency is used to calculate the

MULT_FACT_100NS. This

quoted

is to adjust the clock tic closer to 100ns.

Signed-off-by: Michael Sit Wei Hong

[off-list ref]

What is the initial state of the EEE configuration before the first
call to stmmac_ethtool_op_set_eee()? Does it reflect the default
EEE settings?

The register values before the first call are the default reset values in
the registers. The reset values assumes the clk_eee_i time period is 10ns,
Hence, the reset value is set to 9.
According to the register description,
This value should be programmed such that the
clk_eee_i_time_period * (MULT_FACT_100NS + 1) should be
within 80 ns to 120 ns.

Since we are using a fixed 19.2MHz clk_eee, which is 52ns,
we are setting the value to 1.

Does that hardware default configuration match what is returned by
ethtool --show-eee ?
 
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