Re: [PATCH net v2 1/4] ice: Fix improper extts handling

[Maciej Fijalkowski <maciej.fijalkowski@intel.com>]

On Tue, Jul 02, 2024 at 10:14:54AM -0700, Tony Nguyen wrote:
> From: Milena Olech <milena.olech@intel.com>
> 
> Extts events are disabled and enabled by the application ts2phc.
> However, in case where the driver is removed when the application is
> running, a specific extts event remains enabled and can cause a kernel
> crash.
> As a side effect, when the driver is reloaded and application is started
> again, remaining extts event for the channel from a previous run will
> keep firing and the message "extts on unexpected channel" might be
> printed to the user.
> 
> To avoid that, extts events shall be disabled when PTP is released.
> 
> Fixes: 172db5f91d5f ("ice: add support for auxiliary input/output pins")
> Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
> Co-developed-by: Jacob Keller <jacob.e.keller@intel.com>
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> Signed-off-by: Milena Olech <milena.olech@intel.com>
> Signed-off-by: Karol Kolacinski <karol.kolacinski@intel.com>
> Reviewed-by: Simon Horman <horms@kernel.org>
> Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
> ---
>  drivers/net/ethernet/intel/ice/ice_ptp.c | 105 ++++++++++++++++++-----
>  drivers/net/ethernet/intel/ice/ice_ptp.h |   8 ++
>  2 files changed, 91 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/net/ethernet/intel/ice/ice_ptp.c b/drivers/net/ethernet/intel/ice/ice_ptp.c
> index 0f17fc1181d2..4d6555fadd83 100644
> --- a/drivers/net/ethernet/intel/ice/ice_ptp.c
> +++ b/drivers/net/ethernet/intel/ice/ice_ptp.c
> @@ -1584,27 +1584,24 @@ void ice_ptp_extts_event(struct ice_pf *pf)
>  /**
>   * ice_ptp_cfg_extts - Configure EXTTS pin and channel
>   * @pf: Board private structure
> - * @ena: true to enable; false to disable
>   * @chan: GPIO channel (0-3)
> - * @gpio_pin: GPIO pin
> - * @extts_flags: request flags from the ptp_extts_request.flags
> + * @config: desired EXTTS configuration.
> + * @store: If set to true, the values will be stored
> + *
> + * Configure an external timestamp event on the requested channel.
>   */
> -static int
> -ice_ptp_cfg_extts(struct ice_pf *pf, bool ena, unsigned int chan, u32 gpio_pin,
> -		  unsigned int extts_flags)
> +static void ice_ptp_cfg_extts(struct ice_pf *pf, unsigned int chan,
> +			      struct ice_extts_channel *config, bool store)
>  {
>  	u32 func, aux_reg, gpio_reg, irq_reg;
>  	struct ice_hw *hw = &pf->hw;
>  	u8 tmr_idx;
>  
> -	if (chan > (unsigned int)pf->ptp.info.n_ext_ts)
> -		return -EINVAL;
> -
>  	tmr_idx = hw->func_caps.ts_func_info.tmr_index_owned;
>  
>  	irq_reg = rd32(hw, PFINT_OICR_ENA);
>  
> -	if (ena) {
> +	if (config->ena) {
>  		/* Enable the interrupt */
>  		irq_reg |= PFINT_OICR_TSYN_EVNT_M;
>  		aux_reg = GLTSYN_AUX_IN_0_INT_ENA_M;
> @@ -1613,9 +1610,9 @@ ice_ptp_cfg_extts(struct ice_pf *pf, bool ena, unsigned int chan, u32 gpio_pin,
>  #define GLTSYN_AUX_IN_0_EVNTLVL_FALLING_EDGE	BIT(1)
>  
>  		/* set event level to requested edge */
> -		if (extts_flags & PTP_FALLING_EDGE)
> +		if (config->flags & PTP_FALLING_EDGE)
>  			aux_reg |= GLTSYN_AUX_IN_0_EVNTLVL_FALLING_EDGE;
> -		if (extts_flags & PTP_RISING_EDGE)
> +		if (config->flags & PTP_RISING_EDGE)
>  			aux_reg |= GLTSYN_AUX_IN_0_EVNTLVL_RISING_EDGE;
>  
>  		/* Write GPIO CTL reg.
> @@ -1636,9 +1633,47 @@ ice_ptp_cfg_extts(struct ice_pf *pf, bool ena, unsigned int chan, u32 gpio_pin,
>  
>  	wr32(hw, PFINT_OICR_ENA, irq_reg);
>  	wr32(hw, GLTSYN_AUX_IN(chan, tmr_idx), aux_reg);
> -	wr32(hw, GLGEN_GPIO_CTL(gpio_pin), gpio_reg);
> +	wr32(hw, GLGEN_GPIO_CTL(config->gpio_pin), gpio_reg);
>  
> -	return 0;
> +	if (store)
> +		memcpy(&pf->ptp.extts_channels[chan], config, sizeof(*config));
> +}
> +
> +/**
> + * ice_ptp_disable_all_extts - Disable all EXTTS channels
> + * @pf: Board private structure
> + */
> +static void ice_ptp_disable_all_extts(struct ice_pf *pf)
> +{
> +	struct ice_extts_channel extts_cfg = {};
> +	int i;
> +
> +	for (i = 0; i < pf->ptp.info.n_ext_ts; i++) {
> +		if (pf->ptp.extts_channels[i].ena) {
> +			extts_cfg.gpio_pin = pf->ptp.extts_channels[i].gpio_pin;
> +			extts_cfg.ena = false;
> +			ice_ptp_cfg_extts(pf, i, &extts_cfg, false);
> +		}
> +	}
> +
> +	synchronize_irq(pf->oicr_irq.virq);
> +}
> +
> +/**
> + * ice_ptp_enable_all_extts - Enable all EXTTS channels
> + * @pf: Board private structure
> + *
> + * Called during reset to restore user configuration.
> + */
> +static void ice_ptp_enable_all_extts(struct ice_pf *pf)
> +{
> +	int i;
> +
> +	for (i = 0; i < pf->ptp.info.n_ext_ts; i++) {
> +		if (pf->ptp.extts_channels[i].ena)
> +			ice_ptp_cfg_extts(pf, i, &pf->ptp.extts_channels[i],
> +					  false);
> +	}

Still one redundant pair of braces. Just do:

	for (i = 0; i < pf->ptp.info.n_ext_ts; i++)
		if (pf->ptp.extts_channels[i].ena)
			ice_ptp_cfg_extts(pf, i, &pf->ptp.extts_channels[i],
					  false);

>  }
>