[U-Boot] [PATCH] arm: imx6: Switch DDR3 calibration to wait_for_bit()

[Stefano Babic]

On 02/03/2016 14:49, Marek Vasut wrote:
> Switch the DDR3 calibration from ad-hoc implementation of wait_for_bit()
> to generic implementation of wait_for_bit().
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Stefano Babic <sbabic at denx.de>
> ---
>  arch/arm/cpu/armv7/mx6/ddr.c | 44 ++++++++++++--------------------------------
>  1 file changed, 12 insertions(+), 32 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/mx6/ddr.c b/arch/arm/cpu/armv7/mx6/ddr.c
> index e457feb..1e7ae28 100644
> --- a/arch/arm/cpu/armv7/mx6/ddr.c
> +++ b/arch/arm/cpu/armv7/mx6/ddr.c
> @@ -12,40 +12,20 @@
>  #include <asm/arch/sys_proto.h>
>  #include <asm/io.h>
>  #include <asm/types.h>
> +#include <wait_bit.h>
>  
>  #if defined(CONFIG_MX6QDL) || defined(CONFIG_MX6Q) || defined(CONFIG_MX6D)
>  
> -static int wait_for_bit(void *reg, const uint32_t mask, bool set)
> -{
> -	unsigned int timeout = 1000;
> -	u32 val;
> -
> -	while (--timeout) {
> -		val = readl(reg);
> -		if (!set)
> -			val = ~val;
> -
> -		if ((val & mask) == mask)
> -			return 0;
> -
> -		udelay(1);
> -	}
> -
> -	printf("%s: Timeout (reg=%p mask=%08x wait_set=%i)\n",
> -	      __func__, reg, mask, set);
> -	hang();	/* DRAM couldn't be calibrated, game over :-( */
> -}
> -
>  static void reset_read_data_fifos(void)
>  {
>  	struct mmdc_p_regs *mmdc0 = (struct mmdc_p_regs *)MMDC_P0_BASE_ADDR;
>  
>  	/* Reset data FIFOs twice. */
>  	setbits_le32(&mmdc0->mpdgctrl0, 1 << 31);
> -	wait_for_bit(&mmdc0->mpdgctrl0, 1 << 31, 0);
> +	wait_for_bit("MMDC", &mmdc0->mpdgctrl0, 1 << 31, 0, 100, 0);
>  
>  	setbits_le32(&mmdc0->mpdgctrl0, 1 << 31);
> -	wait_for_bit(&mmdc0->mpdgctrl0, 1 << 31, 0);
> +	wait_for_bit("MMDC", &mmdc0->mpdgctrl0, 1 << 31, 0, 100, 0);
>  }
>  
>  static void precharge_all(const bool cs0_enable, const bool cs1_enable)
> @@ -60,12 +40,12 @@ static void precharge_all(const bool cs0_enable, const bool cs1_enable)
>  	 */
>  	if (cs0_enable) { /* CS0 */
>  		writel(0x04008050, &mmdc0->mdscr);
> -		wait_for_bit(&mmdc0->mdscr, 1 << 14, 1);
> +		wait_for_bit("MMDC", &mmdc0->mdscr, 1 << 14, 1, 100, 0);
>  	}
>  
>  	if (cs1_enable) { /* CS1 */
>  		writel(0x04008058, &mmdc0->mdscr);
> -		wait_for_bit(&mmdc0->mdscr, 1 << 14, 1);
> +		wait_for_bit("MMDC", &mmdc0->mdscr, 1 << 14, 1, 100, 0);
>  	}
>  }
>  
> @@ -164,7 +144,7 @@ int mmdc_do_write_level_calibration(void)
>  	 * 7. Upon completion of this process the MMDC de-asserts
>  	 * the MPWLGCR[HW_WL_EN]
>  	 */
> -	wait_for_bit(&mmdc0->mpwlgcr, 1 << 0, 0);
> +	wait_for_bit("MMDC", &mmdc0->mpwlgcr, 1 << 0, 0, 100, 0);
>  
>  	/*
>  	 * 8. check for any errors: check both PHYs for x64 configuration,
> @@ -289,7 +269,7 @@ int mmdc_do_dqs_calibration(void)
>  		writel(0x00008028, &mmdc0->mdscr);
>  
>  	/* poll to make sure the con_ack bit was asserted */
> -	wait_for_bit(&mmdc0->mdscr, 1 << 14, 1);
> +	wait_for_bit("MMDC", &mmdc0->mdscr, 1 << 14, 1, 100, 0);
>  
>  	/*
>  	 * Check MDMISC register CALIB_PER_CS to see which CS calibration
> @@ -327,7 +307,7 @@ int mmdc_do_dqs_calibration(void)
>  	 * this bit until it clears to indicate completion of the write access.
>  	 */
>  	setbits_le32(&mmdc0->mpswdar0, 1);
> -	wait_for_bit(&mmdc0->mpswdar0, 1 << 0, 0);
> +	wait_for_bit("MMDC", &mmdc0->mpswdar0, 1 << 0, 0, 100, 0);
>  
>  	/* Set the RD_DL_ABS# bits to their default values
>  	 * (will be calibrated later in the read delay-line calibration).
> @@ -372,7 +352,7 @@ int mmdc_do_dqs_calibration(void)
>  	setbits_le32(&mmdc0->mpdgctrl0, 5 << 28);
>  
>  	/* Poll for completion.  MPDGCTRL0[HW_DG_EN] should be 0 */
> -	wait_for_bit(&mmdc0->mpdgctrl0, 1 << 28, 0);
> +	wait_for_bit("MMDC", &mmdc0->mpdgctrl0, 1 << 28, 0, 100, 0);
>  
>  	/*
>  	 * Check to see if any errors were encountered during calibration
> @@ -431,7 +411,7 @@ int mmdc_do_dqs_calibration(void)
>  	 * setting MPRDDLHWCTL[HW_RD_DL_EN] = 0.   Also, ensure that
>  	 * no error bits were set.
>  	 */
> -	wait_for_bit(&mmdc0->mprddlhwctl, 1 << 4, 0);
> +	wait_for_bit("MMDC", &mmdc0->mprddlhwctl, 1 << 4, 0, 100, 0);
>  
>  	/* check both PHYs for x64 configuration, if x32, check only PHY0 */
>  	if (readl(&mmdc0->mprddlhwctl) & 0x0000000f)
> @@ -484,7 +464,7 @@ int mmdc_do_dqs_calibration(void)
>  	 * by setting MPWRDLHWCTL[HW_WR_DL_EN] = 0.
>  	 * Also, ensure that no error bits were set.
>  	 */
> -	wait_for_bit(&mmdc0->mpwrdlhwctl, 1 << 4, 0);
> +	wait_for_bit("MMDC", &mmdc0->mpwrdlhwctl, 1 << 4, 0, 100, 0);
>  
>  	/* Check both PHYs for x64 configuration, if x32, check only PHY0 */
>  	if (readl(&mmdc0->mpwrdlhwctl) & 0x0000000f)
> @@ -532,7 +512,7 @@ int mmdc_do_dqs_calibration(void)
>  	writel(0x0, &mmdc0->mdscr);	/* CS0 */
>  
>  	/* Poll to make sure the con_ack bit is clear */
> -	wait_for_bit(&mmdc0->mdscr, 1 << 14, 0);
> +	wait_for_bit("MMDC", &mmdc0->mdscr, 1 << 14, 0, 100, 0);
>  
>  	/*
>  	 * Print out the registers that were updated as a result
> 

Reviewed-by: Stefano Babic <sbabic at denx.de>

Best regards,
Stefano Babic

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