[PATCH v7 02/13] arm: mach-k3: common: Add CANUART wakeup check helpers

[Kumar, Udit]

On 12/10/2025 7:38 PM, Markus Schneider-Pargmann (TI.com) wrote:
> Add dedicated helper functions to check CANUART wake registers and magic
> word. This helps determining if we are in a wakeup or if CAN IO
> isolation has to be removed.
>
> Also add a helper to detect a low power mode exit/resume.
>
> Tested-by: Anshul Dalal <anshuld at ti.com>
> Signed-off-by: Markus Schneider-Pargmann (TI.com) <msp at baylibre.com>
> ---
>   arch/arm/mach-k3/common.c                | 19 +++++++++++++++++++
>   arch/arm/mach-k3/common.h                |  1 +
>   arch/arm/mach-k3/include/mach/hardware.h |  6 ++++++
>   3 files changed, 26 insertions(+)
>
> diff --git a/arch/arm/mach-k3/common.c b/arch/arm/mach-k3/common.c
> index 760aaad03411441e3cc169f2501134cf69dcbee6..a80cf87ce65a44c386539ade17c0f435e09de841 100644
> --- a/arch/arm/mach-k3/common.c
> +++ b/arch/arm/mach-k3/common.c
> @@ -115,6 +115,25 @@ void mmr_unlock(uintptr_t base, u32 partition)
>   	writel(CTRLMMR_LOCK_KICK1_UNLOCK_VAL, part_base + CTRLMMR_LOCK_KICK1);
>   }
>   
> +static bool wkup_ctrl_canuart_wakeup_active(void)
> +{
> +	return !!(readl(WKUP_CTRL_MMR0_BASE + WKUP_CTRL_MMR_CANUART_WAKE_STAT1) &
> +		WKUP_CTRL_MMR_CANUART_WAKE_STAT1_CANUART_IO_MODE);
> +}
> +
> +static bool wkup_ctrl_canuart_magic_word_set(void)
> +{
> +	return readl(WKUP_CTRL_MMR0_BASE + WKUP_CTRL_MMR_CANUART_WAKE_OFF_MODE_STAT) ==
> +		WKUP_CTRL_MMR_CANUART_WAKE_OFF_MODE_STAT_MW;
> +}
> +
> +bool wkup_ctrl_is_lpm_exit(void)
> +{
> +	return IS_ENABLED(CONFIG_K3_IODDR) &&
> +		wkup_ctrl_canuart_wakeup_active() &&
> +		wkup_ctrl_canuart_magic_word_set();
> +}

May not be valid for all SOC,  either move into some am62xx_base.c or 
make it  __weak, so that other SOCs can over-ride this if needed.


> +
>   bool is_rom_loaded_sysfw(struct rom_extended_boot_data *data)
>   {
> [..]