From 78abc3b8815b2ab6ebe9d309310e7e010ae54376 Mon Sep 17 00:00:00 2001 From: ian Date: Mon, 22 Apr 2019 05:00:29 +0000 Subject: [PATCH] MFC r336094, r336096 r336094: Catch up with improvements in RTC handling... It's no longer necessary to ignore the timestamp passed in to settime() due to inaccuracy, the core routines now pass in a nanosecond-accurate time freshly-obtained before calling each driver's settime() method. Also, add calls to the new debugging output helpers. r336096: Make the imx6_snvs driver usable as a module, add pnp info. Add a manpage. --- share/man/man4/man4.arm/Makefile | 1 + share/man/man4/man4.arm/imx6_snvs.4 | 78 +++++++++++++++++++++++++++++ sys/arm/freescale/imx/imx6_snvs.c | 35 ++++++++----- sys/modules/imx/Makefile | 1 + sys/modules/imx/imx6_snvs/Makefile | 15 ++++++ 5 files changed, 118 insertions(+), 12 deletions(-) create mode 100644 share/man/man4/man4.arm/imx6_snvs.4 create mode 100644 sys/modules/imx/imx6_snvs/Makefile diff --git a/share/man/man4/man4.arm/Makefile b/share/man/man4/man4.arm/Makefile index eeb7c8a781b..a6c8aadf516 100644 --- a/share/man/man4/man4.arm/Makefile +++ b/share/man/man4/man4.arm/Makefile @@ -5,6 +5,7 @@ PACKAGE=runtime-manuals MAN= cgem.4 \ devcfg.4 \ imx6_ahci.4 \ + imx6_snvs.4 \ imx_wdog.4 \ mge.4 \ npe.4 \ diff --git a/share/man/man4/man4.arm/imx6_snvs.4 b/share/man/man4/man4.arm/imx6_snvs.4 new file mode 100644 index 00000000000..d372d067cb1 --- /dev/null +++ b/share/man/man4/man4.arm/imx6_snvs.4 @@ -0,0 +1,78 @@ +.\" +.\" Copyright (c) 2018 Ian Lepore +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, +.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT +.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF +.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd July 8, 2018 +.Dt IMX6_SNVS 4 +.Os +.Sh NAME +.Nm imx6_snvs +.Nd device driver for the NXP i.MX6 on-chip Realtime Clock +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following line in your +kernel configuration file: +.Bd -ragged -offset indent +.Cd "device imx6_snvs" +.Ed +.Pp +Alternatively, to load the driver as a +module at boot time, place the following line in +.Xr loader.conf 5 : +.Bd -literal -offset indent +imx6_snvs_load="YES" +.Ed +.Sh DESCRIPTION +The +.Nm +driver provides +support for the i.MX6 on-chip realtime clock. +It provides the time of day with a resolution of approximately +30 microseconds. +.Pp +.Sq SNVS +stands for Secure Non-Volatile Storage, and refers to the subsystem +within the chip that (optionally) remains powered by a battery when +the rest of the system is powered down. +The on-chip realtime clock is part of that subsystem. +Other features of the SNVS subsystem are related to security, tamper +monitoring, and power control; the +.Nm +driver does not currently support those features. +.Pp +Many i.MX6 systems do not use a battery to provide power to the SNVS +due to its relatively high power draw. In such systems, this driver +is able to provide a very accurate time following a reboot, but cannot +provide time at all if the power is cycled. If the system provides an +i2c or other type of alternate realtime clock with lower resolution, +there is value in configuring both clock drivers. +Doing so allows SNVS to provide accurate time after a reboot, while the +external clock provides approximate time after power cycling. +.Sh HISTORY +The +.Nm +driver first appeared in +.Fx 12.0 . diff --git a/sys/arm/freescale/imx/imx6_snvs.c b/sys/arm/freescale/imx/imx6_snvs.c index 82dee8b8ddc..457cc7671a9 100644 --- a/sys/arm/freescale/imx/imx6_snvs.c +++ b/sys/arm/freescale/imx/imx6_snvs.c @@ -137,36 +137,34 @@ snvs_gettime(device_t dev, struct timespec *ts) *ts = sbttots(counter1); + clock_dbgprint_ts(sc->dev, CLOCK_DBG_READ, ts); + return (0); } static int -snvs_settime(device_t dev, struct timespec *unused) +snvs_settime(device_t dev, struct timespec *ts) { struct snvs_softc *sc; - struct bintime bt; sbintime_t sbt; sc = device_get_softc(dev); /* - * Ignore the inaccurate time passed in from the common clock code and - * obtain a time worthy of our 30us accuracy. - */ - bintime(&bt); - bt.sec -= utc_offset(); - sbt = bttosbt(bt); - - /* - * It takes two clock cycles for the counter to start after setting the - * enable bit, so add two SBT_LSBs to what we're about to set. + * The hardware format is the same as sbt (with fewer fractional bits), + * so first convert the time to sbt. It takes two clock cycles for the + * counter to start after setting the enable bit, so add two SBT_LSBs to + * what we're about to set. */ + sbt = tstosbt(*ts); sbt += 2 << SBT_LSB; snvs_rtc_enable(sc, false); WR4(sc, SNVS_LPSRTCMR, (uint32_t)(sbt >> (SBT_LSB + 32))); WR4(sc, SNVS_LPSRTCLR, (uint32_t)(sbt >> (SBT_LSB))); snvs_rtc_enable(sc, true); + clock_dbgprint_ts(sc->dev, CLOCK_DBG_WRITE, ts); + return (0); } @@ -206,9 +204,21 @@ snvs_attach(device_t dev) return (0); } +static int +snvs_detach(device_t dev) +{ + struct snvs_softc *sc; + + sc = device_get_softc(dev); + clock_unregister(sc->dev); + bus_release_resource(sc->dev, SYS_RES_MEMORY, 0, sc->memres); + return (0); +} + static device_method_t snvs_methods[] = { DEVMETHOD(device_probe, snvs_probe), DEVMETHOD(device_attach, snvs_attach), + DEVMETHOD(device_detach, snvs_detach), /* clock_if methods */ DEVMETHOD(clock_gettime, snvs_gettime), @@ -226,3 +236,4 @@ static driver_t snvs_driver = { static devclass_t snvs_devclass; DRIVER_MODULE(snvs, simplebus, snvs_driver, snvs_devclass, 0, 0); +SIMPLEBUS_PNP_INFO(compat_data); diff --git a/sys/modules/imx/Makefile b/sys/modules/imx/Makefile index c37d7214669..096c9c3528b 100644 --- a/sys/modules/imx/Makefile +++ b/sys/modules/imx/Makefile @@ -4,6 +4,7 @@ SUBDIR = \ ../ffec \ imx6_ahci \ + imx6_snvs \ imx_i2c \ imx_spi \ imx_wdog \ diff --git a/sys/modules/imx/imx6_snvs/Makefile b/sys/modules/imx/imx6_snvs/Makefile new file mode 100644 index 00000000000..eca421ffe4c --- /dev/null +++ b/sys/modules/imx/imx6_snvs/Makefile @@ -0,0 +1,15 @@ +# $FreeBSD$ + +.PATH: ${SRCTOP}/sys/arm/freescale/imx + +KMOD= imx6_snvs +SRCS= imx6_snvs.c + +# Generated files... +SRCS+= \ + bus_if.h \ + clock_if.h \ + device_if.h \ + ofw_bus_if.h \ + +.include -- 2.45.0