[PATCH] ARM: rockchip: keep reset control around
Heiko Stuebner
heiko at sntech.de
Thu May 21 14:13:46 PDT 2026
Am Donnerstag, 21. Mai 2026, 23:09:15 Mitteleuropäische Sommerzeit schrieb Heiko Stuebner:
> Do not put the reset control, retain exclusive control over it.
> After turning on a CPU, the corresponding reset line must stay
> deasserted.
>
> This also avoids calling reset_control_put() before workqueues
> are operational.
>
> Fixes: 78ebbff6d1a0 ("reset: handle removing supplier before consumers")
> Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
> Tested-by: Steven Price <steven.price at arm.com>
> Signed-off-by: Heiko Stuebner <heiko at sntech.de>
Forgot to add Bartosz to the Cc list, sorry
Heiko
> ---
> arch/arm/mach-rockchip/platsmp.c | 16 ++++++++++------
> 1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
> index f432d22bfed8..f659d894bfae 100644
> --- a/arch/arm/mach-rockchip/platsmp.c
> +++ b/arch/arm/mach-rockchip/platsmp.c
> @@ -34,6 +34,7 @@ static int ncores;
>
> static struct regmap *pmu;
> static int has_pmu = true;
> +static struct reset_control *cpu_rstc[4];
>
> static int pmu_power_domain_is_on(int pd)
> {
> @@ -64,9 +65,11 @@ static struct reset_control *rockchip_get_core_reset(int cpu)
> static int pmu_set_power_domain(int pd, bool on)
> {
> u32 val = (on) ? 0 : BIT(pd);
> - struct reset_control *rstc = rockchip_get_core_reset(pd);
> + struct reset_control *rstc;
> int ret;
>
> + rstc = pd < ARRAY_SIZE(cpu_rstc) ? cpu_rstc[pd] : ERR_PTR(-EINVAL);
> +
> if (IS_ERR(rstc) && read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
> pr_err("%s: could not get reset control for core %d\n",
> __func__, pd);
> @@ -100,11 +103,8 @@ static int pmu_set_power_domain(int pd, bool on)
> }
> }
>
> - if (!IS_ERR(rstc)) {
> - if (on)
> - reset_control_deassert(rstc);
> - reset_control_put(rstc);
> - }
> + if (!IS_ERR(rstc) && on)
> + reset_control_deassert(rstc);
>
> return 0;
> }
> @@ -312,6 +312,10 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus)
> ncores = ((l2ctlr >> 24) & 0x3) + 1;
> }
>
> + /* Collect cpu core reset control for each core */
> + for (i = 0; i < ncores; i++)
> + cpu_rstc[i] = rockchip_get_core_reset(i);
> +
> /* Make sure that all cores except the first are really off */
> for (i = 1; i < ncores; i++)
> pmu_set_power_domain(0 + i, false);
>
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