kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

clk: sunxi-ng: fix PLL_CPUX adjusting on H3

Browse source 
When adjusting PLL_CPUX on H3, the PLL is temporarily driven
too high, and the system becomes unstable (oopses or hangs).

Add a notifier to avoid this situation by temporarily switching
to a known stable 24 MHz oscillator.

Signed-off-by: Ondrej Jirman <megous@megous.com>
Tested-by: Lutz Sammer <johns98@gmx.net>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
This commit is contained in:
Ondrej Jirman 2016-11-25 01:28:47 +01:00 committed by Maxime Ripard
parent 7ce7d89f48
commit a43c96427e
1 changed files with 10 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
drivers/clk/sunxi-ng/ccu-sun8i-h3.c
View file

@ -803,6 +803,13 @@ static const struct sunxi_ccu_desc sun8i_h3_ccu_desc = {
.num_resets = ARRAY_SIZE(sun8i_h3_ccu_resets),
};
static struct ccu_mux_nb sun8i_h3_cpu_nb = {
.common = &cpux_clk.common,
.cm = &cpux_clk.mux,
.delay_us = 1, /* > 8 clock cycles at 24 MHz */
.bypass_index = 1, /* index of 24 MHz oscillator */
};
static void __init sun8i_h3_ccu_setup(struct device_node *node)
{
void __iomem *reg;
@ -821,6 +828,9 @@ static void __init sun8i_h3_ccu_setup(struct device_node *node)
writel(val | (3 << 16), reg + SUN8I_H3_PLL_AUDIO_REG);
sunxi_ccu_probe(node, reg, &sun8i_h3_ccu_desc);
ccu_mux_notifier_register(pll_cpux_clk.common.hw.clk,
&sun8i_h3_cpu_nb);
}
CLK_OF_DECLARE(sun8i_h3_ccu, "allwinner,sun8i-h3-ccu",
sun8i_h3_ccu_setup);