Messages in this thread Patch in this message | | | From | <> | Subject | Re: [PATCH net v3] net: macb: Correct usage of MACB_CAPS_CLK_HW_CHG flag | Date | Mon, 4 Jan 2021 14:04:06 +0000 |
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Hi Charles,
On 04.01.2021 12:38, Charles Keepax wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > A new flag MACB_CAPS_CLK_HW_CHG was added and all callers of > macb_set_tx_clk were gated on the presence of this flag. > > - if (!clk) > + if (!bp->tx_clk || !(bp->caps & MACB_CAPS_CLK_HW_CHG)) > > However the flag was not added to anything other than the new > sama7g5_gem, turning that function call into a no op for all other > systems. This breaks the networking on Zynq. > > The commit message adding this states: a new capability so that > macb_set_tx_clock() to not be called for IPs having this > capability > > This strongly implies that present of the flag was intended to skip > the function not absence of the flag. Update the if statement to > this effect, which repairs the existing users.
Yes, the presence of the flag should involve skipping the calling of clk_set_rate() since the IP logic would take care of proper clock division depending on the link speed. I wrongly cherry pick this one from internal branches. Sorry for this breakage.
> > Fixes: daafa1d33cc9 ("net: macb: add capability to not set the clock rate") > Suggested-by: Andrew Lunn <andrew@lunn.ch> > Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
> --- > > Changes since v1: > - Updated flag semantics to skip function, as appears to have been > intended by the initial commit. > > Changes since v2: > - Adding "net" to the subject line > > Thanks, > Charles > > drivers/net/ethernet/cadence/macb_main.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c > index d5d910916c2e8..814a5b10141d1 100644 > --- a/drivers/net/ethernet/cadence/macb_main.c > +++ b/drivers/net/ethernet/cadence/macb_main.c > @@ -467,7 +467,7 @@ static void macb_set_tx_clk(struct macb *bp, int speed) > { > long ferr, rate, rate_rounded; > > - if (!bp->tx_clk || !(bp->caps & MACB_CAPS_CLK_HW_CHG)) > + if (!bp->tx_clk || (bp->caps & MACB_CAPS_CLK_HW_CHG)) > return; > > switch (speed) { > -- > 2.11.0 > | |