Re: [PATCH 2/3] pata/at91: use new introduce smc accessor

[Ryan Mallon <rmallon@gmail.com>]

On 09/12/11 02:23, Jean-Christophe PLAGNIOL-VILLARD wrote:

> this will allow to use the pata_at91 on a single zImage
> 
> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
> Cc: linux-ide@vger.kernel.org


Some comments below,

~Ryan

> ---
> Hi,
> 
> 	it's depends on other patch for AT91 can we apply via at91
> 
> Best Regards,
> J.
>  drivers/ata/pata_at91.c |   43 +++++++++++++++++++++----------------------
>  1 files changed, 21 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
> index 5249e6d..c8d1154 100644
> --- a/drivers/ata/pata_at91.c
> +++ b/drivers/ata/pata_at91.c
> @@ -207,11 +207,11 @@ static void set_smc_timing(struct device *dev, struct ata_device *adev,
>  {
>  	int ret = 0;
>  	int use_iordy;
> +	struct sam9_smc_config smc;
>  	unsigned int t6z;         /* data tristate time in ns */
>  	unsigned int cycle;       /* SMC Cycle width in MCK ticks */
>  	unsigned int setup;       /* SMC Setup width in MCK ticks */
>  	unsigned int pulse;       /* CFIOR and CFIOW pulse width in MCK ticks */
> -	unsigned int cs_setup = 0;/* CS4 or CS5 setup width in MCK ticks */
>  	unsigned int cs_pulse;    /* CS4 or CS5 pulse width in MCK ticks*/
>  	unsigned int tdf_cycles;  /* SMC TDF MCK ticks */
>  	unsigned long mck_hz;     /* MCK frequency in Hz */
> @@ -244,26 +244,25 @@ static void set_smc_timing(struct device *dev, struct ata_device *adev,
>  	}
>  
>  	dev_dbg(dev, "Use IORDY=%u, TDF Cycles=%u\n", use_iordy, tdf_cycles);
> -	info->mode |= AT91_SMC_TDF_(tdf_cycles);
>  
>  	/* write SMC Setup Register */
> -	at91_sys_write(AT91_SMC_SETUP(info->cs),
> -			AT91_SMC_NWESETUP_(setup) |
> -			AT91_SMC_NRDSETUP_(setup) |
> -			AT91_SMC_NCS_WRSETUP_(cs_setup) |
> -			AT91_SMC_NCS_RDSETUP_(cs_setup));
> +	smc.nrd_setup = setup;
> +	smc.nwe_setup = smc.nrd_setup;
> +	smc.ncs_read_setup = 0;
> +	smc.ncs_write_setup = smc.ncs_read_setup;
>  	/* write SMC Pulse Register */
> -	at91_sys_write(AT91_SMC_PULSE(info->cs),
> -			AT91_SMC_NWEPULSE_(pulse) |
> -			AT91_SMC_NRDPULSE_(pulse) |
> -			AT91_SMC_NCS_WRPULSE_(cs_pulse) |
> -			AT91_SMC_NCS_RDPULSE_(cs_pulse));
> +	smc.nrd_pulse = pulse;
> +	smc.nwe_pulse = smc.nrd_pulse;
> +	smc.ncs_read_pulse =cs_pulse;


Nitpick: Whitespace around the = operator.

> +	smc.ncs_write_pulse = smc.ncs_read_pulse;
>  	/* write SMC Cycle Register */
> -	at91_sys_write(AT91_SMC_CYCLE(info->cs),
> -			AT91_SMC_NWECYCLE_(cycle) |
> -			AT91_SMC_NRDCYCLE_(cycle));
> +	smc.read_cycle = cycle;
> +	smc.write_cycle = smc.read_cycle;
>  	/* write SMC Mode Register*/
> -	at91_sys_write(AT91_SMC_MODE(info->cs), info->mode);
> +	smc.tdf_cycles = tdf_cycles;


The "write SMC Mode Register" comment should be removed.

> +	smc.mode = info->mode;
> +
> +	sam9_smc_configure(0, info->cs, &smc);


This new function returns an int, should we be checking the return value
here?

>  }
>  
>  static void pata_at91_set_piomode(struct ata_port *ap, struct ata_device *adev)
> @@ -288,20 +287,20 @@ static unsigned int pata_at91_data_xfer_noirq(struct ata_device *dev,
>  	struct at91_ide_info *info = dev->link->ap->host->private_data;
>  	unsigned int consumed;
>  	unsigned long flags;
> -	unsigned int mode;
> +	struct sam9_smc_config smc;
>  
>  	local_irq_save(flags);
> -	mode = at91_sys_read(AT91_SMC_MODE(info->cs));
> +	sam9_smc_read_mode(0, info->cs, &smc);
>  
>  	/* set 16bit mode before writing data */
> -	at91_sys_write(AT91_SMC_MODE(info->cs),
> -			(mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_16);
> +	smc.mode = (smc.mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_16;
> +	sam9_smc_write_mode(0, info->cs, &smc);


Do sam9_smc_read/write_mode really need to pass the whole smc structure?
The only fields used are mode and tdf_cycles. It might be clearer to
pass those directly.

Also the original code here doesn't write tdf_cycles as part of the
mode. Perhaps it would be better to have sam9_smc_write_mode to be:

  int sam9_smc_write_mode(int id, int cs, unsigned mode);

and in set_smc_timing above explicitly or in the tdf_cycles bits?

>  
>  	consumed = ata_sff_data_xfer(dev, buf, buflen, rw);
>  
>  	/* restore 8bit mode after data is written */
> -	at91_sys_write(AT91_SMC_MODE(info->cs),
> -			(mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_8);
> +	smc.mode = (smc.mode & ~AT91_SMC_DBW) | AT91_SMC_DBW_8;
> +	sam9_smc_write_mode(0, info->cs, &smc);
>  
>  	local_irq_restore(flags);
>  	return consumed;