diff options
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/mmc/host/sdhci-omap.c | 90 |
2 files changed, 91 insertions, 1 deletions
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig index ada79f8face6..e26b8145efb3 100644 --- a/drivers/mmc/host/Kconfig +++ b/drivers/mmc/host/Kconfig @@ -977,6 +977,8 @@ config MMC_SDHCI_XENON config MMC_SDHCI_OMAP tristate "TI SDHCI Controller Support" depends on MMC_SDHCI_PLTFM && OF + select THERMAL + select TI_SOC_THERMAL help This selects the Secure Digital Host Controller Interface (SDHCI) support present in TI's DRA7 SOCs. The controller supports diff --git a/drivers/mmc/host/sdhci-omap.c b/drivers/mmc/host/sdhci-omap.c index ecf905066c56..c11c18a9aacb 100644 --- a/drivers/mmc/host/sdhci-omap.c +++ b/drivers/mmc/host/sdhci-omap.c @@ -27,6 +27,7 @@ #include <linux/regulator/consumer.h> #include <linux/pinctrl/consumer.h> #include <linux/sys_soc.h> +#include <linux/thermal.h> #include "sdhci-pltfm.h" @@ -290,15 +291,19 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode) struct sdhci_host *host = mmc_priv(mmc); struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); struct sdhci_omap_host *omap_host = sdhci_pltfm_priv(pltfm_host); + struct thermal_zone_device *thermal_dev; struct device *dev = omap_host->dev; struct mmc_ios *ios = &mmc->ios; u32 start_window = 0, max_window = 0; + bool single_point_failure = false; bool dcrc_was_enabled = false; u8 cur_match, prev_match = 0; u32 length = 0, max_len = 0; u32 phase_delay = 0; + int temperature; int ret = 0; u32 reg; + int i; /* clock tuning is not needed for upto 52MHz */ if (ios->clock <= 52000000) @@ -308,6 +313,16 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode) if (ios->timing == MMC_TIMING_UHS_SDR50 && !(reg & CAPA2_TSDR50)) return 0; + thermal_dev = thermal_zone_get_zone_by_name("cpu_thermal"); + if (IS_ERR(thermal_dev)) { + dev_err(dev, "Unable to get thermal zone for tuning\n"); + return PTR_ERR(thermal_dev); + } + + ret = thermal_zone_get_temp(thermal_dev, &temperature); + if (ret) + return ret; + reg = sdhci_omap_readl(omap_host, SDHCI_OMAP_DLL); reg |= DLL_SWT; sdhci_omap_writel(omap_host, SDHCI_OMAP_DLL, reg); @@ -325,6 +340,11 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode) omap_host->is_tuning = true; + /* + * Stage 1: Search for a maximum pass window ignoring any + * any single point failures. If the tuning value ends up + * near it, move away from it in stage 2 below + */ while (phase_delay <= MAX_PHASE_DELAY) { sdhci_omap_set_dll(omap_host, phase_delay); @@ -332,10 +352,15 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode) if (cur_match) { if (prev_match) { length++; + } else if (single_point_failure) { + /* ignore single point failure */ + length++; } else { start_window = phase_delay; length = 1; } + } else { + single_point_failure = prev_match; } if (length > max_len) { @@ -353,13 +378,76 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode) goto tuning_error; } + /* + * Assign tuning value as a ratio of maximum pass window based + * on temperature + */ + if (temperature < -20000) + phase_delay = min(max_window + 4 * max_len - 24, + max_window + + DIV_ROUND_UP(13 * max_len, 16) * 4); + else if (temperature < 20000) + phase_delay = max_window + DIV_ROUND_UP(9 * max_len, 16) * 4; + else if (temperature < 40000) + phase_delay = max_window + DIV_ROUND_UP(8 * max_len, 16) * 4; + else if (temperature < 70000) + phase_delay = max_window + DIV_ROUND_UP(7 * max_len, 16) * 4; + else if (temperature < 90000) + phase_delay = max_window + DIV_ROUND_UP(5 * max_len, 16) * 4; + else if (temperature < 120000) + phase_delay = max_window + DIV_ROUND_UP(4 * max_len, 16) * 4; + else + phase_delay = max_window + DIV_ROUND_UP(3 * max_len, 16) * 4; + + /* + * Stage 2: Search for a single point failure near the chosen tuning + * value in two steps. First in the +3 to +10 range and then in the + * +2 to -10 range. If found, move away from it in the appropriate + * direction by the appropriate amount depending on the temperature. + */ + for (i = 3; i <= 10; i++) { + sdhci_omap_set_dll(omap_host, phase_delay + i); + + if (mmc_send_tuning(mmc, opcode, NULL)) { + if (temperature < 10000) + phase_delay += i + 6; + else if (temperature < 20000) + phase_delay += i - 12; + else if (temperature < 70000) + phase_delay += i - 8; + else + phase_delay += i - 6; + + goto single_failure_found; + } + } + + for (i = 2; i >= -10; i--) { + sdhci_omap_set_dll(omap_host, phase_delay + i); + + if (mmc_send_tuning(mmc, opcode, NULL)) { + if (temperature < 10000) + phase_delay += i + 12; + else if (temperature < 20000) + phase_delay += i + 8; + else if (temperature < 70000) + phase_delay += i + 8; + else if (temperature < 90000) + phase_delay += i + 10; + else + phase_delay += i + 12; + + goto single_failure_found; + } + } + +single_failure_found: reg = sdhci_omap_readl(omap_host, SDHCI_OMAP_AC12); if (!(reg & AC12_SCLK_SEL)) { ret = -EIO; goto tuning_error; } - phase_delay = max_window + 4 * (max_len >> 1); sdhci_omap_set_dll(omap_host, phase_delay); omap_host->is_tuning = false; |