clk: sunxi-ng: v3s: fix incorrect postdivider on pll-audio

Commit 46060be6d8 ("clk: sunxi-ng: v3s: use sigma-delta modulation for audio-pll")
changed the audio pll on the Allwinner V3s and V3 SoCs to use
sigma-delta modulation. In the process the declaration of fixed postdivider
providing "pll-audio" was adjusted to provide the desired clock rates from
the now sigma-delta modulated pll.
However, while the divider used for calculations by the clock framework
was adjusted the actual divider programmed into the hardware in
sun8i_v3_v3s_ccu_init was left at "divide by four". This broke the
"pll-audio" clock, now only providing quater the expected clock rate.
It would in general be desirable to program the postdivider for
"pll-audio" to four, such that a broader range of frequencies were
available on the pll outputs. But the clock for the integrated codec
"ac-dig" does not feature a mux that allows to select from all pll outputs
as it is just a simple clock gate connected to "pll-audio". Thus we need
to set the postdivider to one to be able to provide the 22.5792MHz and
24.576MHz rates required by the internal sun4i codec.

This patches fixes the incorrect clock rate by forcing the postdivider to
one in sun8i_v3_v3s_ccu_init.

Fixes: 46060be6d8 ("clk: sunxi-ng: v3s: use sigma-delta modulation for audio-pll")
Signed-off-by: Tobias Schramm <t.schramm@manjaro.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20210513131315.2059451-1-t.schramm@manjaro.org
This commit is contained in:
Tobias Schramm 2021-05-13 15:13:15 +02:00 committed by Maxime Ripard
parent 6efb943b86
commit 47e4dc4e63
No known key found for this signature in database
GPG key ID: E3EF0D6F671851C5

View file

@ -817,10 +817,10 @@ static void __init sun8i_v3_v3s_ccu_init(struct device_node *node,
return;
}
/* Force the PLL-Audio-1x divider to 4 */
/* Force the PLL-Audio-1x divider to 1 */
val = readl(reg + SUN8I_V3S_PLL_AUDIO_REG);
val &= ~GENMASK(19, 16);
writel(val | (3 << 16), reg + SUN8I_V3S_PLL_AUDIO_REG);
writel(val, reg + SUN8I_V3S_PLL_AUDIO_REG);
sunxi_ccu_probe(node, reg, ccu_desc);
}