On Mon, 10 Dec 2018 at 14:23, Faiz Abbas <faiz_abbas@xxxxxx> wrote: > > Hi Uffe, > > On 05/12/18 7:20 PM, Ulf Hansson wrote: > > On Fri, 30 Nov 2018 at 06:53, Faiz Abbas <faiz_abbas@xxxxxx> wrote: > >> > >> Hi Kishon, > >> > >> On 30/11/18 10:10 AM, Kishon Vijay Abraham I wrote: > >>> Hi Faiz, > >>> > >>> On 30/11/18 12:35 AM, Faiz Abbas 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> > >>>> --- > >>>> 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 1b58739d9744..6d3553f06f27 100644 > >>>> --- a/drivers/mmc/host/Kconfig > >>>> +++ b/drivers/mmc/host/Kconfig > >>>> @@ -969,6 +969,8 @@ 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 b3cb39d0db6f..9ccce7ef3a60 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" > >>>> > >>>> @@ -286,14 +287,18 @@ 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; > >>>> 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) > >>>> @@ -303,6 +308,16 @@ 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); > >>>> + } > >>> > >>> Can't we get thermal zone once during probe? > >>> > >> > >> Tuning is also (ideally) supposed to happen only once per enumeration. > >> Also it doesn't make sense to get a thermal zone for lower speed systems > >> that won't do tuning. > > > > Currently sdhci-omap calls pm_runtime_get_sync() during probe, and > > then keeps the host device runtime resumed until ->remove() is called > > on it. I assume you are going to change that, at some point!? > > > > In other words, what will happen to the host device when it becomes > > runtime suspended? Is re-tuning needed when it gets runtime resumed, > > which is the case for many other sdhci variants? > > There are no plans to support runtime_suspend()/resume() any time in the > near future. If its ok with you, I would like to get this patch in > without any changes. We can change it in case a need for > runtime_suspend()/_resume() does arise. Right, I am okay with that. Due to recent changes to sdhci-omap $subject patch doesn't apply, can you please rebase!? Additionally, I realized that we should fold in patch updating the DT doc for sdhci-omap, adding the property for the thermal zone. I regards to that, I am wondering if "cpu_thermal", is really the correct name of the zone. The point is, I am guessing the zone could change along with the SoCs/platforms. Kind regards Uffe
