Re: [PATCH 2/2] ptp_qoriq: support FIPER3

[Vladimir Oltean <olteanv@xxxxxxxxx>]

Hi Yangbo,

On Sat, Sep 12, 2020 at 11:30:06AM +0800, Yangbo Lu wrote:
> The FIPER3 (fixed interval period pulse generator) is supported on
> DPAA2 and ENETC network controller hardware. This patch is to support
> it in ptp_qoriq driver.
> 
> Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxx>
> ---
>  drivers/ptp/ptp_qoriq.c       | 23 ++++++++++++++++++++++-
>  include/linux/fsl/ptp_qoriq.h |  3 +++
>  2 files changed, 25 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/ptp/ptp_qoriq.c b/drivers/ptp/ptp_qoriq.c
> index c09c16be..68beb1b 100644
> --- a/drivers/ptp/ptp_qoriq.c
> +++ b/drivers/ptp/ptp_qoriq.c
> @@ -72,6 +72,10 @@ static void set_fipers(struct ptp_qoriq *ptp_qoriq)
>  	set_alarm(ptp_qoriq);
>  	ptp_qoriq->write(&regs->fiper_regs->tmr_fiper1, ptp_qoriq->tmr_fiper1);
>  	ptp_qoriq->write(&regs->fiper_regs->tmr_fiper2, ptp_qoriq->tmr_fiper2);
> +
> +	if (ptp_qoriq->fiper3_support)
> +		ptp_qoriq->write(&regs->fiper_regs->tmr_fiper3,
> +				 ptp_qoriq->tmr_fiper3);
>  }
>  
>  int extts_clean_up(struct ptp_qoriq *ptp_qoriq, int index, bool update_event)
> @@ -366,6 +370,7 @@ static u32 ptp_qoriq_nominal_freq(u32 clk_src)
>   *   "fsl,tmr-add"
>   *   "fsl,tmr-fiper1"
>   *   "fsl,tmr-fiper2"
> + *   "fsl,tmr-fiper3" (required only for DPAA2 and ENETC hardware)
>   *   "fsl,max-adj"
>   *
>   * Return 0 if success
> @@ -412,6 +417,7 @@ static int ptp_qoriq_auto_config(struct ptp_qoriq *ptp_qoriq,
>  	ptp_qoriq->tmr_add = freq_comp;
>  	ptp_qoriq->tmr_fiper1 = DEFAULT_FIPER1_PERIOD - ptp_qoriq->tclk_period;
>  	ptp_qoriq->tmr_fiper2 = DEFAULT_FIPER2_PERIOD - ptp_qoriq->tclk_period;
> +	ptp_qoriq->tmr_fiper3 = DEFAULT_FIPER3_PERIOD - ptp_qoriq->tclk_period;
>  
>  	/* max_adj = 1000000000 * (freq_ratio - 1.0) - 1
>  	 * freq_ratio = reference_clock_freq / nominal_freq
> @@ -446,6 +452,13 @@ int ptp_qoriq_init(struct ptp_qoriq *ptp_qoriq, void __iomem *base,
>  	else
>  		ptp_qoriq->extts_fifo_support = false;
>  
> +	if (of_device_is_compatible(node, "fsl,dpaa2-ptp") ||
> +	    of_device_is_compatible(node, "fsl,enetc-ptp")) {
> +		ptp_qoriq->fiper3_support = true;
> +	} else {
> +		ptp_qoriq->fiper3_support = false;
> +	}

Since struct ptp_qoriq is kzalloc()-ed, maybe you can skip the "else"
branch?

> +
>  	if (of_property_read_u32(node,
>  				 "fsl,tclk-period", &ptp_qoriq->tclk_period) ||
>  	    of_property_read_u32(node,
> @@ -457,7 +470,10 @@ int ptp_qoriq_init(struct ptp_qoriq *ptp_qoriq, void __iomem *base,
>  	    of_property_read_u32(node,
>  				 "fsl,tmr-fiper2", &ptp_qoriq->tmr_fiper2) ||
>  	    of_property_read_u32(node,
> -				 "fsl,max-adj", &ptp_qoriq->caps.max_adj)) {
> +				 "fsl,max-adj", &ptp_qoriq->caps.max_adj) ||
> +	    (of_property_read_u32(node,
> +				 "fsl,tmr-fiper3", &ptp_qoriq->tmr_fiper3) &&
> +	     ptp_qoriq->fiper3_support)) {

Could you check for the "ptp_qoriq->fiper3_support" boolean first, so
that a useless device tree property lookup is not performed?

>  		pr_warn("device tree node missing required elements, try automatic configuration\n");
>  
>  		if (ptp_qoriq_auto_config(ptp_qoriq, node))
> @@ -502,6 +518,11 @@ int ptp_qoriq_init(struct ptp_qoriq *ptp_qoriq, void __iomem *base,
>  	ptp_qoriq->write(&regs->ctrl_regs->tmr_prsc, ptp_qoriq->tmr_prsc);
>  	ptp_qoriq->write(&regs->fiper_regs->tmr_fiper1, ptp_qoriq->tmr_fiper1);
>  	ptp_qoriq->write(&regs->fiper_regs->tmr_fiper2, ptp_qoriq->tmr_fiper2);
> +
> +	if (ptp_qoriq->fiper3_support)
> +		ptp_qoriq->write(&regs->fiper_regs->tmr_fiper3,
> +				 ptp_qoriq->tmr_fiper3);
> +
>  	set_alarm(ptp_qoriq);
>  	ptp_qoriq->write(&regs->ctrl_regs->tmr_ctrl,
>  			 tmr_ctrl|FIPERST|RTPE|TE|FRD);
> diff --git a/include/linux/fsl/ptp_qoriq.h b/include/linux/fsl/ptp_qoriq.h
> index 884b8f8..01acebe 100644
> --- a/include/linux/fsl/ptp_qoriq.h
> +++ b/include/linux/fsl/ptp_qoriq.h
> @@ -136,6 +136,7 @@ struct ptp_qoriq_registers {
>  #define DEFAULT_TMR_PRSC	2
>  #define DEFAULT_FIPER1_PERIOD	1000000000
>  #define DEFAULT_FIPER2_PERIOD	1000000000
> +#define DEFAULT_FIPER3_PERIOD	1000000000
>  
>  struct ptp_qoriq {
>  	void __iomem *base;
> @@ -147,6 +148,7 @@ struct ptp_qoriq {
>  	struct dentry *debugfs_root;
>  	struct device *dev;
>  	bool extts_fifo_support;
> +	bool fiper3_support;
>  	int irq;
>  	int phc_index;
>  	u32 tclk_period;  /* nanoseconds */
> @@ -155,6 +157,7 @@ struct ptp_qoriq {
>  	u32 cksel;
>  	u32 tmr_fiper1;
>  	u32 tmr_fiper2;
> +	u32 tmr_fiper3;
>  	u32 (*read)(unsigned __iomem *addr);
>  	void (*write)(unsigned __iomem *addr, u32 val);
>  };
> -- 
> 2.7.4
> 

With that,

Acked-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>

Thanks for doing this!
-Vladimir