On Wed, Jan 02, 2019 at 10:29:31AM -0800, Olof Johansson wrote: > Hi, > > > On Wed, Dec 12, 2018 at 1:20 AM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > > > > + Thermal maintainers > > > > On Tue, 11 Dec 2018 at 15:20, Faiz Abbas <faiz_abbas@xxxxxx> wrote: > > > > > > Errata i929 in certain OMAP5/DRA7XX/AM57XX silicon revisions > > > (SPRZ426D - November 2014 - Revised February 2018 [1]) mentions > > > unexpected tuning pattern errors. A small failure band may be present > > > in the tuning range which may be missed by the current algorithm. > > > Furthermore, the failure bands vary with temperature leading to > > > different optimum tuning values for different temperatures. > > > > > > As suggested in the related Application Report (SPRACA9B - October 2017 > > > - Revised July 2018 [2]), tuning should be done in two stages. > > > In stage 1, assign the optimum ratio in the maximum pass window for the > > > current temperature. In stage 2, if the chosen value is close to the > > > small failure band, move away from it in the appropriate direction. > > > > > > References: > > > [1] http://www.ti.com/lit/pdf/sprz426 > > > [2] http://www.ti.com/lit/pdf/SPRACA9 > > > > > > Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx> > > > Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> > > > --- > > > drivers/mmc/host/Kconfig | 2 + > > > drivers/mmc/host/sdhci-omap.c | 90 ++++++++++++++++++++++++++++++++++- > > > 2 files changed, 91 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig > > > index 5fa580cec831..d8f984483ab0 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 f588ab679cb0..b75c55011fcb 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" > > > > > > @@ -286,15 +287,19 @@ 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) > > > @@ -304,6 +309,16 @@ 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"); > > > > I couldn't find a corresponding call to a put function, like > > "thermal_zone_put()" or whatever, which made me realize that the > > thermal zone API is incomplete. Or depending on how you put it, it > > lacks object reference counting, unless I am missing something. > > > > For example, what happens if the thermal zone becomes unregistered > > between this point and when you call thermal_zone_get_temp() a couple > > of line below. I assume it's a known problem, but just wanted to point > > it out. > > Yes, there is no ref counting. Specially because the get zones usages were too specific, and mostly used in application cases that module would not really be removed. Though not a good excuse, still, not very problematic. Now, if the API is getting other usages, then refcounting may be necessary. > > > + 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; > > > + > > > > [...] > > > > Anyway, I have applied this for next, thanks! > > This is throwing errors on builds of keystone_defconfig in next and mainline: > > http://arm-soc.lixom.net/buildlogs/next/next-20190102/buildall.arm.keystone_defconfig.log.passed > > WARNING: unmet direct dependencies detected for TI_SOC_THERMAL > Depends on [n]: THERMAL [=y] && (ARCH_HAS_BANDGAP [=n] || > COMPILE_TEST [=n]) && HAS_IOMEM [=y] > Selected by [y]: > - MMC_SDHCI_OMAP [=y] && MMC [=y] && MMC_SDHCI_PLTFM [=y] && OF [=y] > > So, thermal depends on ARCH_HAS_BANDGAP, which keystone doesn't provide. > > Selecting a major framework such as THERMAL from a driver config is > likely not the right solution anyway, especially since THERMAL does > provide stubbed out versions of the functions if it's not enabled. Yeah, that seams a bit up-side-down. Can you guys give a bit more of context? Why do you need the cpu thermal zone ? From patch description, looks like you want to have your own zone then apply different tuning values based on temperature (range?). Why do you need to mess up with cpu_thermal zone? Don't you have a bandgap in the mem controller for this application? > > > -Olof
