diff mbox series

mmc: sdhci-esdhc-imx: optimize the manual tuing logic to get the best timing

Message ID 20230831032647.3128702-1-haibo.chen@nxp.com (mailing list archive)
State New, archived
Headers show
Series mmc: sdhci-esdhc-imx: optimize the manual tuing logic to get the best timing | expand

Commit Message

Bough Chen Aug. 31, 2023, 3:26 a.m. UTC
From: Haibo Chen <haibo.chen@nxp.com>

Current manual tuning logic only get the first pass window, but
this pass window maybe not the best pass window.

Now find all the pass window, and chose the largest pass window,
and use the average value of this largest pass window to get the
best timing.

Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
---
 drivers/mmc/host/sdhci-esdhc-imx.c | 52 +++++++++++++++++++++---------
 1 file changed, 36 insertions(+), 16 deletions(-)

Comments

Adrian Hunter Sept. 12, 2023, 10:02 a.m. UTC | #1
On 31/08/23 06:26, haibo.chen@nxp.com wrote:
> From: Haibo Chen <haibo.chen@nxp.com>
> 
> Current manual tuning logic only get the first pass window, but
> this pass window maybe not the best pass window.
> 
> Now find all the pass window, and chose the largest pass window,
> and use the average value of this largest pass window to get the
> best timing.
> 
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
>  drivers/mmc/host/sdhci-esdhc-imx.c | 52 +++++++++++++++++++++---------
>  1 file changed, 36 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
> index 6170b7121f36..4cbbc0a786a0 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -1154,32 +1154,52 @@ static void esdhc_post_tuning(struct sdhci_host *host)
>  	writel(reg, host->ioaddr + ESDHC_MIX_CTRL);
>  }
>  
> +/*
> + * find the largest pass window, and use the average delay of this
> + * largest window to get the best timing.
> + */
>  static int esdhc_executing_tuning(struct sdhci_host *host, u32 opcode)
>  {
>  	int min, max, avg, ret;
> +	int win_length, target_min, target_max, target_win_length;
>  
> -	/* find the mininum delay first which can pass tuning */
>  	min = ESDHC_TUNE_CTRL_MIN;
> -	while (min < ESDHC_TUNE_CTRL_MAX) {
> -		esdhc_prepare_tuning(host, min);
> -		if (!mmc_send_tuning(host->mmc, opcode, NULL))
> -			break;
> -		min += ESDHC_TUNE_CTRL_STEP;
> -	}
> -
> -	/* find the maxinum delay which can not pass tuning */
> -	max = min + ESDHC_TUNE_CTRL_STEP;
> +	max = ESDHC_TUNE_CTRL_MIN;
> +	target_win_length = 0;
>  	while (max < ESDHC_TUNE_CTRL_MAX) {
> -		esdhc_prepare_tuning(host, max);
> -		if (mmc_send_tuning(host->mmc, opcode, NULL)) {
> -			max -= ESDHC_TUNE_CTRL_STEP;
> -			break;
> +		/* find the mininum delay first which can pass tuning */
> +		while (min < ESDHC_TUNE_CTRL_MAX) {
> +			esdhc_prepare_tuning(host, min);
> +			if (!mmc_send_tuning(host->mmc, opcode, NULL))
> +				break;
> +			min += ESDHC_TUNE_CTRL_STEP;
>  		}
> -		max += ESDHC_TUNE_CTRL_STEP;
> +
> +		/* find the maxinum delay which can not pass tuning */
> +		max = min + ESDHC_TUNE_CTRL_STEP;
> +		while (max < ESDHC_TUNE_CTRL_MAX) {
> +			esdhc_prepare_tuning(host, max);
> +			if (mmc_send_tuning(host->mmc, opcode, NULL)) {
> +				max -= ESDHC_TUNE_CTRL_STEP;
> +				break;
> +			}
> +			max += ESDHC_TUNE_CTRL_STEP;
> +		}
> +
> +		win_length = max - min + 1;
> +		/* get the largest pass window */
> +		if (win_length > target_win_length) {
> +			target_win_length = win_length;
> +			target_min = min;
> +			target_max = max;
> +		}
> +
> +		/* continue to find the next pass window */
> +		min = max + ESDHC_TUNE_CTRL_STEP;
>  	}
>  
>  	/* use average delay to get the best timing */
> -	avg = (min + max) / 2;
> +	avg = (target_min + target_max) / 2;
>  	esdhc_prepare_tuning(host, avg);
>  	ret = mmc_send_tuning(host->mmc, opcode, NULL);
>  	esdhc_post_tuning(host);
Ulf Hansson Sept. 14, 2023, 1:02 p.m. UTC | #2
On Thu, 31 Aug 2023 at 05:22, <haibo.chen@nxp.com> wrote:
>
> From: Haibo Chen <haibo.chen@nxp.com>
>
> Current manual tuning logic only get the first pass window, but
> this pass window maybe not the best pass window.
>
> Now find all the pass window, and chose the largest pass window,
> and use the average value of this largest pass window to get the
> best timing.
>
> Signed-off-by: Haibo Chen <haibo.chen@nxp.com>

Applied for next, thanks!

Kind regards
Uffe


> ---
>  drivers/mmc/host/sdhci-esdhc-imx.c | 52 +++++++++++++++++++++---------
>  1 file changed, 36 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
> index 6170b7121f36..4cbbc0a786a0 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -1154,32 +1154,52 @@ static void esdhc_post_tuning(struct sdhci_host *host)
>         writel(reg, host->ioaddr + ESDHC_MIX_CTRL);
>  }
>
> +/*
> + * find the largest pass window, and use the average delay of this
> + * largest window to get the best timing.
> + */
>  static int esdhc_executing_tuning(struct sdhci_host *host, u32 opcode)
>  {
>         int min, max, avg, ret;
> +       int win_length, target_min, target_max, target_win_length;
>
> -       /* find the mininum delay first which can pass tuning */
>         min = ESDHC_TUNE_CTRL_MIN;
> -       while (min < ESDHC_TUNE_CTRL_MAX) {
> -               esdhc_prepare_tuning(host, min);
> -               if (!mmc_send_tuning(host->mmc, opcode, NULL))
> -                       break;
> -               min += ESDHC_TUNE_CTRL_STEP;
> -       }
> -
> -       /* find the maxinum delay which can not pass tuning */
> -       max = min + ESDHC_TUNE_CTRL_STEP;
> +       max = ESDHC_TUNE_CTRL_MIN;
> +       target_win_length = 0;
>         while (max < ESDHC_TUNE_CTRL_MAX) {
> -               esdhc_prepare_tuning(host, max);
> -               if (mmc_send_tuning(host->mmc, opcode, NULL)) {
> -                       max -= ESDHC_TUNE_CTRL_STEP;
> -                       break;
> +               /* find the mininum delay first which can pass tuning */
> +               while (min < ESDHC_TUNE_CTRL_MAX) {
> +                       esdhc_prepare_tuning(host, min);
> +                       if (!mmc_send_tuning(host->mmc, opcode, NULL))
> +                               break;
> +                       min += ESDHC_TUNE_CTRL_STEP;
>                 }
> -               max += ESDHC_TUNE_CTRL_STEP;
> +
> +               /* find the maxinum delay which can not pass tuning */
> +               max = min + ESDHC_TUNE_CTRL_STEP;
> +               while (max < ESDHC_TUNE_CTRL_MAX) {
> +                       esdhc_prepare_tuning(host, max);
> +                       if (mmc_send_tuning(host->mmc, opcode, NULL)) {
> +                               max -= ESDHC_TUNE_CTRL_STEP;
> +                               break;
> +                       }
> +                       max += ESDHC_TUNE_CTRL_STEP;
> +               }
> +
> +               win_length = max - min + 1;
> +               /* get the largest pass window */
> +               if (win_length > target_win_length) {
> +                       target_win_length = win_length;
> +                       target_min = min;
> +                       target_max = max;
> +               }
> +
> +               /* continue to find the next pass window */
> +               min = max + ESDHC_TUNE_CTRL_STEP;
>         }
>
>         /* use average delay to get the best timing */
> -       avg = (min + max) / 2;
> +       avg = (target_min + target_max) / 2;
>         esdhc_prepare_tuning(host, avg);
>         ret = mmc_send_tuning(host->mmc, opcode, NULL);
>         esdhc_post_tuning(host);
> --
> 2.34.1
>
diff mbox series

Patch

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 6170b7121f36..4cbbc0a786a0 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -1154,32 +1154,52 @@  static void esdhc_post_tuning(struct sdhci_host *host)
 	writel(reg, host->ioaddr + ESDHC_MIX_CTRL);
 }
 
+/*
+ * find the largest pass window, and use the average delay of this
+ * largest window to get the best timing.
+ */
 static int esdhc_executing_tuning(struct sdhci_host *host, u32 opcode)
 {
 	int min, max, avg, ret;
+	int win_length, target_min, target_max, target_win_length;
 
-	/* find the mininum delay first which can pass tuning */
 	min = ESDHC_TUNE_CTRL_MIN;
-	while (min < ESDHC_TUNE_CTRL_MAX) {
-		esdhc_prepare_tuning(host, min);
-		if (!mmc_send_tuning(host->mmc, opcode, NULL))
-			break;
-		min += ESDHC_TUNE_CTRL_STEP;
-	}
-
-	/* find the maxinum delay which can not pass tuning */
-	max = min + ESDHC_TUNE_CTRL_STEP;
+	max = ESDHC_TUNE_CTRL_MIN;
+	target_win_length = 0;
 	while (max < ESDHC_TUNE_CTRL_MAX) {
-		esdhc_prepare_tuning(host, max);
-		if (mmc_send_tuning(host->mmc, opcode, NULL)) {
-			max -= ESDHC_TUNE_CTRL_STEP;
-			break;
+		/* find the mininum delay first which can pass tuning */
+		while (min < ESDHC_TUNE_CTRL_MAX) {
+			esdhc_prepare_tuning(host, min);
+			if (!mmc_send_tuning(host->mmc, opcode, NULL))
+				break;
+			min += ESDHC_TUNE_CTRL_STEP;
 		}
-		max += ESDHC_TUNE_CTRL_STEP;
+
+		/* find the maxinum delay which can not pass tuning */
+		max = min + ESDHC_TUNE_CTRL_STEP;
+		while (max < ESDHC_TUNE_CTRL_MAX) {
+			esdhc_prepare_tuning(host, max);
+			if (mmc_send_tuning(host->mmc, opcode, NULL)) {
+				max -= ESDHC_TUNE_CTRL_STEP;
+				break;
+			}
+			max += ESDHC_TUNE_CTRL_STEP;
+		}
+
+		win_length = max - min + 1;
+		/* get the largest pass window */
+		if (win_length > target_win_length) {
+			target_win_length = win_length;
+			target_min = min;
+			target_max = max;
+		}
+
+		/* continue to find the next pass window */
+		min = max + ESDHC_TUNE_CTRL_STEP;
 	}
 
 	/* use average delay to get the best timing */
-	avg = (min + max) / 2;
+	avg = (target_min + target_max) / 2;
 	esdhc_prepare_tuning(host, avg);
 	ret = mmc_send_tuning(host->mmc, opcode, NULL);
 	esdhc_post_tuning(host);