diff options
| author | Haibo Chen <haibo.chen@nxp.com> | 2025-04-09 15:55:48 +0800 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2025-05-14 16:59:17 +0200 |
| commit | 8cdba34313712e0dbc4c5650c8f2dcf315c13e6f (patch) | |
| tree | 3f710354e842e36e77e6c985a7302cdcdf63ed3b /drivers/mmc | |
| parent | mmc: sdhci-esdhc-imx: widen auto-tuning window for standard tuning (diff) | |
| download | linux-8cdba34313712e0dbc4c5650c8f2dcf315c13e6f.tar.gz linux-8cdba34313712e0dbc4c5650c8f2dcf315c13e6f.zip | |
mmc: sdhci-esdhc-imx: widen auto-tuning window for manual tuning
Expand the auto-tuning window width from 0 to 3 for manual tuning to
account for sampling point shifts caused by temperature change. This change
is based on hardware recommendation, providing enough margin for the
auto-tuning logic to locate valid sampling points.
When config the manual tuning final sample delay, need deduct the auto
tuning window width according to the IP logic.
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: Luke Wang <ziniu.wang_1@nxp.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20250409075550.3413032-5-ziniu.wang_1@nxp.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/sdhci-esdhc-imx.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index 5c8a00864c1d..f94b5f08b432 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -85,7 +85,8 @@ #define ESDHC_TUNE_CTRL_MAX ((1 << 7) - 1) #define ESDHC_TUNE_CTRL_STATUS_TAP_SEL_PRE_MASK GENMASK(30, 24) #define ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_PRE_MASK GENMASK(14, 8) - +#define ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_OUT_MASK GENMASK(7, 4) +#define ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_POST_MASK GENMASK(3, 0) /* strobe dll register */ #define ESDHC_STROBE_DLL_CTRL 0x70 #define ESDHC_STROBE_DLL_CTRL_ENABLE (1 << 0) @@ -243,6 +244,7 @@ struct esdhc_platform_data { unsigned int tuning_start_tap; /* The start delay cell point in tuning procedure */ unsigned int strobe_dll_delay_target; /* The delay cell for strobe pad (read clock) */ unsigned int saved_tuning_delay_cell; /* save the value of tuning delay cell */ + unsigned int saved_auto_tuning_window; /* save the auto tuning window width */ }; struct esdhc_soc_data { @@ -1211,6 +1213,7 @@ 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; + u32 clk_tune_ctrl_status; min = ESDHC_TUNE_CTRL_MIN; max = ESDHC_TUNE_CTRL_MIN; @@ -1250,6 +1253,23 @@ static int esdhc_executing_tuning(struct sdhci_host *host, u32 opcode) /* use average delay to get the best timing */ avg = (target_min + target_max) / 2; esdhc_prepare_tuning(host, avg); + + /* + * adjust the delay according to tuning window, make preparation + * for the auto-tuning logic. According to hardware suggest, need + * to config the auto tuning window width to 3, to make the auto + * tuning logic have enough space to handle the sample point shift + * caused by temperature change. + */ + clk_tune_ctrl_status = FIELD_PREP(ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_PRE_MASK, + avg - ESDHC_AUTO_TUNING_WINDOW) | + FIELD_PREP(ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_OUT_MASK, + ESDHC_AUTO_TUNING_WINDOW) | + FIELD_PREP(ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_POST_MASK, + ESDHC_AUTO_TUNING_WINDOW); + + writel(clk_tune_ctrl_status, host->ioaddr + ESDHC_TUNE_CTRL_STATUS); + ret = mmc_send_tuning(host->mmc, opcode, NULL); esdhc_post_tuning(host); @@ -1652,7 +1672,11 @@ static void sdhc_esdhc_tuning_restore(struct sdhci_host *host) writel(reg, host->ioaddr + ESDHC_MIX_CTRL); writel(FIELD_PREP(ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_PRE_MASK, - imx_data->boarddata.saved_tuning_delay_cell), + imx_data->boarddata.saved_tuning_delay_cell) | + FIELD_PREP(ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_OUT_MASK, + ESDHC_AUTO_TUNING_WINDOW) | + FIELD_PREP(ESDHC_TUNE_CTRL_STATUS_DLY_CELL_SET_POST_MASK, + ESDHC_AUTO_TUNING_WINDOW), host->ioaddr + ESDHC_TUNE_CTRL_STATUS); } } |