Subject: [PATCH V3 12/18] ARM: OMAP2+: Add additional GPMC timing parameters

From: [email-masked] (Rob Herring)
Date: Mon, 18 Mar 2013 09:07:09 -0500

On 03/15/2013 10:21 AM, Jon Hunter wrote:
> Some of the GPMC timings parameters are currently missing from the GPMC
> device-tree binding. Add these parameters to the binding documentation
> as well as code to read them.
> 
> The existing code in gpmc_read_timings_dt() is checking the value of
> of_property_read_u32() and only is successful storing the value read
> in the gpmc_timings structure. Checking the return value in this case
> is not necessary and we can simply read the value, if present, and
> store directly in the gpmc_timings structure. Therefore, simplify the
> code by removing these checks.
> 
> The comment in the gpmc_read_timings_dt() function, "only for OMAP3430"
> is also incorrect as it is applicable to all OMAP3+ devices. So correct
> this too.
> 
> Signed-off-by: Jon Hunter <[email-masked]>
> ---
>  Documentation/devicetree/bindings/bus/ti-gpmc.txt |   25 +++++-
>  arch/arm/mach-omap2/gpmc.c                        |   93 ++++++++++-----------
>  2 files changed, 66 insertions(+), 52 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/bus/ti-gpmc.txt b/Documentation/devicetree/bindings/bus/ti-gpmc.txt
> index 6fde1cf..a63bd93 100644
> --- a/Documentation/devicetree/bindings/bus/ti-gpmc.txt
> +++ b/Documentation/devicetree/bindings/bus/ti-gpmc.txt
> @@ -56,10 +56,27 @@ Timing properties for child nodes. All are optional and default to 0.
>   - gpmc,oe-off:		Deassertion time
>  
>   Access time and cycle time timings corresponding to GPMC_CONFIG5:
> - - gpmc,page-burst-access: Multiple access word delay
> - - gpmc,access:		Start-cycle to first data valid delay
> - - gpmc,rd-cycle:	Total read cycle time
> - - gpmc,wr-cycle:	Total write cycle time
> + - gpmc,page-burst-access: 	Multiple access word delay
> + - gpmc,access:			Start-cycle to first data valid delay
> + - gpmc,rd-cycle:		Total read cycle time
> + - gpmc,wr-cycle:		Total write cycle time
> + - gpmc,bus-turnaround:		Turn-around time between successive accesses
> + - gpmc,cycle2cycle-delay:	Delay between chip-select pulses
> + - gpmc,clk-activation: 	GPMC clock activation time
> + - gpmc,wait-monitoring:	Start of wait monitoring with regard to valid
> +				data

What units are these in? If in nanoseconds, can you append "-ns"

> +
> +Boolean timing parameters. If property is present parameter enabled and
> +disabled if omitted:
> + - gpmc,adv-extra-delay:	ADV signal is delayed by half GPMC clock
> + - gpmc,cs-extra-delay:		CS signal is delayed by half GPMC clock
> + - gpmc,cycle2cycle-diffcsen:	Add "cycle2cycle-delay" between successive
> +				accesses to a different CS
> + - gpmc,cycle2cycle-samecsen:	Add "cycle2cycle-delay" between successive
> +				accesses to the same CS
> + - gpmc,oe-extra-delay:		OE signal is delayed by half GPMC clock
> + - gpmc,we-extra-delay:		WE signal is delayed by half GPMC clock
> + - gpmc,time-para-granularity:	Multiply all access times by 2
>  
>  The following are only applicable to OMAP3+ and AM335x:
>   - gpmc,wr-access
> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> index 85b1a35..c928a8c 100644
> --- a/arch/arm/mach-omap2/gpmc.c
> +++ b/arch/arm/mach-omap2/gpmc.c
> @@ -1274,67 +1274,64 @@ void gpmc_read_settings_dt(struct device_node *np, struct gpmc_settings *p)
>  static void __maybe_unused gpmc_read_timings_dt(struct device_node *np,
>  						struct gpmc_timings *gpmc_t)
>  {
> -	u32 val;
> -
>  	memset(gpmc_t, 0, sizeof(*gpmc_t));
>  
>  	/* minimum clock period for syncronous mode */
> -	if (!of_property_read_u32(np, "gpmc,sync-clk", &val))
> -		gpmc_t->sync_clk = val;
> +	of_property_read_u32(np, "gpmc,sync-clk", &gpmc_t->sync_clk);
>  
>  	/* chip select timtings */
> -	if (!of_property_read_u32(np, "gpmc,cs-on", &val))
> -		gpmc_t->cs_on = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,cs-rd-off", &val))
> -		gpmc_t->cs_rd_off = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,cs-wr-off", &val))
> -		gpmc_t->cs_wr_off = val;
> +	of_property_read_u32(np, "gpmc,cs-on", &gpmc_t->cs_on);
> +	of_property_read_u32(np, "gpmc,cs-rd-off", &gpmc_t->cs_rd_off);
> +	of_property_read_u32(np, "gpmc,cs-wr-off", &gpmc_t->cs_wr_off);
>  
>  	/* ADV signal timings */
> -	if (!of_property_read_u32(np, "gpmc,adv-on", &val))
> -		gpmc_t->adv_on = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,adv-rd-off", &val))
> -		gpmc_t->adv_rd_off = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,adv-wr-off", &val))
> -		gpmc_t->adv_wr_off = val;
> +	of_property_read_u32(np, "gpmc,adv-on", &gpmc_t->adv_on);
> +	of_property_read_u32(np, "gpmc,adv-rd-off", &gpmc_t->adv_rd_off);
> +	of_property_read_u32(np, "gpmc,adv-wr-off", &gpmc_t->adv_wr_off);
>  
>  	/* WE signal timings */
> -	if (!of_property_read_u32(np, "gpmc,we-on", &val))
> -		gpmc_t->we_on = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,we-off", &val))
> -		gpmc_t->we_off = val;
> +	of_property_read_u32(np, "gpmc,we-on", &gpmc_t->we_on);
> +	of_property_read_u32(np, "gpmc,we-off", &gpmc_t->we_off);
>  
>  	/* OE signal timings */
> -	if (!of_property_read_u32(np, "gpmc,oe-on", &val))
> -		gpmc_t->oe_on = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,oe-off", &val))
> -		gpmc_t->oe_off = val;
> +	of_property_read_u32(np, "gpmc,oe-on", &gpmc_t->oe_on);
> +	of_property_read_u32(np, "gpmc,oe-off", &gpmc_t->oe_off);
>  
>  	/* access and cycle timings */
> -	if (!of_property_read_u32(np, "gpmc,page-burst-access", &val))
> -		gpmc_t->page_burst_access = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,access", &val))
> -		gpmc_t->access = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,rd-cycle", &val))
> -		gpmc_t->rd_cycle = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,wr-cycle", &val))
> -		gpmc_t->wr_cycle = val;
> -
> -	/* only for OMAP3430 */
> -	if (!of_property_read_u32(np, "gpmc,wr-access", &val))
> -		gpmc_t->wr_access = val;
> -
> -	if (!of_property_read_u32(np, "gpmc,wr-data-mux-bus", &val))
> -		gpmc_t->wr_data_mux_bus = val;
> +	of_property_read_u32(np, "gpmc,page-burst-access",
> +			     &gpmc_t->page_burst_access);
> +	of_property_read_u32(np, "gpmc,access", &gpmc_t->access);
> +	of_property_read_u32(np, "gpmc,rd-cycle", &gpmc_t->rd_cycle);
> +	of_property_read_u32(np, "gpmc,wr-cycle", &gpmc_t->wr_cycle);
> +	of_property_read_u32(np, "gpmc,bus-turnaround",
> +			     &gpmc_t->bus_turnaround);
> +	of_property_read_u32(np, "gpmc,cycle2cycle-delay",
> +			     &gpmc_t->cycle2cycle_delay);
> +	of_property_read_u32(np, "gpmc,wait-monitoring",
> +			     &gpmc_t->wait_monitoring);
> +	of_property_read_u32(np, "gpmc,clk-activation",
> +			     &gpmc_t->clk_activation);
> +
> +	/* only applicable to OMAP3+ */
> +	of_property_read_u32(np, "gpmc,wr-access", &gpmc_t->wr_access);
> +	of_property_read_u32(np, "gpmc,wr-data-mux-bus",
> +			     &gpmc_t->wr_data_mux_bus);
> +
> +	/* bool timing parameters */
> +	if (of_find_property(np, "gpmc,cycle2cycle-diffcsen", NULL))
> +		gpmc_t->bool_timings.cycle2cyclediffcsen = true;
> +	if (of_find_property(np, "gpmc,cycle2cycle-samecsen", NULL))
> +		gpmc_t->bool_timings.cycle2cyclesamecsen = true;
> +	if (of_find_property(np, "gpmc,we-extra-delay", NULL))
> +		gpmc_t->bool_timings.we_extra_delay = true;
> +	if (of_find_property(np, "gpmc,oe-extra-delay", NULL))
> +		gpmc_t->bool_timings.oe_extra_delay = true;
> +	if (of_find_property(np, "gpmc,adv-extra-delay", NULL))
> +		gpmc_t->bool_timings.adv_extra_delay = true;
> +	if (of_find_property(np, "gpmc,cs-extra-delay", NULL))
> +		gpmc_t->bool_timings.cs_extra_delay = true;
> +	if (of_find_property(np, "gpmc,time-para-granularity", NULL))
> +		gpmc_t->bool_timings.time_para_granularity = true;

of_property_read_bool doesn't work for these?

Rob