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+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
+ * Copyright (c) 2014 Steven Lawrance <stl@koffein.net>
+ * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * Analog PLL and power regulator driver for Freescale i.MX6 family of SoCs.
+ * Also, temperature montoring and cpu frequency control. It was Freescale who
+ * kitchen-sinked this device, not us. :)
+ *
+ * We don't really do anything with analog PLLs, but the registers for
+ * controlling them belong to the same block as the power regulator registers.
+ * Since the newbus hierarchy makes it hard for anyone other than us to get at
+ * them, we just export a couple public functions to allow the imx6 CCM clock
+ * driver to read and write those registers.
+ *
+ * We also don't do anything about power regulation yet, but when the need
+ * arises, this would be the place for that code to live.
+ *
+ * I have no idea where the "anatop" name comes from. It's in the standard DTS
+ * source describing i.MX6 SoCs, and in the linux and u-boot code which comes
+ * from Freescale, but it's not in the SoC manual.
+ *
+ * Note that temperature values throughout this code are handled in two types of
+ * units. Items with '_cnt' in the name use the hardware temperature count
+ * units (higher counts are lower temperatures). Items with '_val' in the name
+ * are deci-Celcius, which are converted to/from deci-Kelvins in the sysctl
+ * handlers (dK is the standard unit for temperature in sysctl).
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/callout.h>
+#include <sys/kernel.h>
+#include <sys/limits.h>
+#include <sys/sysctl.h>
+#include <sys/module.h>
+#include <sys/bus.h>
+#include <sys/rman.h>
+
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+
+#include <machine/bus.h>
+
+#include <arm/arm/mpcore_timervar.h>
+#include <arm/freescale/fsl_ocotpreg.h>
+#include <arm/freescale/fsl_ocotpvar.h>
+#include <arm/freescale/imx/imx_ccmvar.h>
+#include <arm/freescale/imx/imx_machdep.h>
+#include <arm/freescale/imx/imx6_anatopreg.h>
+#include <arm/freescale/imx/imx6_anatopvar.h>
+
+static struct resource_spec imx6_anatop_spec[] = {
+ { SYS_RES_MEMORY, 0, RF_ACTIVE },
+ { -1, 0 }
+};
+#define MEMRES 0
+#define IRQRES 1
+
+struct imx6_anatop_softc {
+ device_t dev;
+ struct resource *res[2];
+ struct intr_config_hook
+ intr_setup_hook;
+ uint32_t cpu_curmhz;
+ uint32_t cpu_curmv;
+ uint32_t cpu_minmhz;
+ uint32_t cpu_minmv;
+ uint32_t cpu_maxmhz;
+ uint32_t cpu_maxmv;
+ uint32_t cpu_maxmhz_hw;
+ boolean_t cpu_overclock_enable;
+ boolean_t cpu_init_done;
+ uint32_t refosc_mhz;
+ void *temp_intrhand;
+ uint32_t temp_high_val;
+ uint32_t temp_high_cnt;
+ uint32_t temp_last_cnt;
+ uint32_t temp_room_cnt;
+ struct callout temp_throttle_callout;
+ sbintime_t temp_throttle_delay;
+ uint32_t temp_throttle_reset_cnt;
+ uint32_t temp_throttle_trigger_cnt;
+ uint32_t temp_throttle_val;
+};
+
+static struct imx6_anatop_softc *imx6_anatop_sc;
+
+/*
+ * Table of "operating points".
+ * These are combinations of frequency and voltage blessed by Freescale.
+ * While the datasheet says the ARM voltage can be as low as 925mV at
+ * 396MHz, it also says that the ARM and SOC voltages can't differ by
+ * more than 200mV, and the minimum SOC voltage is 1150mV, so that
+ * dictates the 950mV entry in this table.
+ */
+static struct oppt {
+ uint32_t mhz;
+ uint32_t mv;
+} imx6_oppt_table[] = {
+ { 396, 950},
+ { 792, 1150},
+ { 852, 1225},
+ { 996, 1225},
+ {1200, 1275},
+};
+
+/*
+ * Table of CPU max frequencies. This is used to translate the max frequency
+ * value (0-3) from the ocotp CFG3 register into a mhz value that can be looked
+ * up in the operating points table.
+ */
+static uint32_t imx6_ocotp_mhz_tab[] = {792, 852, 996, 1200};
+
+#define TZ_ZEROC 2731 /* deci-Kelvin <-> deci-Celcius offset. */
+
+uint32_t
+imx6_anatop_read_4(bus_size_t offset)
+{
+
+ KASSERT(imx6_anatop_sc != NULL, ("imx6_anatop_read_4 sc NULL"));
+
+ return (bus_read_4(imx6_anatop_sc->res[MEMRES], offset));
+}
+
+void
+imx6_anatop_write_4(bus_size_t offset, uint32_t value)
+{
+
+ KASSERT(imx6_anatop_sc != NULL, ("imx6_anatop_write_4 sc NULL"));
+
+ bus_write_4(imx6_anatop_sc->res[MEMRES], offset, value);
+}
+
+static void
+vdd_set(struct imx6_anatop_softc *sc, int mv)
+{
+ int newtarg, newtargSoc, oldtarg;
+ uint32_t delay, pmureg;
+ static boolean_t init_done = false;
+
+ /*
+ * The datasheet says VDD_PU and VDD_SOC must be equal, and VDD_ARM
+ * can't be more than 50mV above or 200mV below them. We keep them the
+ * same except in the case of the lowest operating point, which is
+ * handled as a special case below.
+ */
+
+ pmureg = imx6_anatop_read_4(IMX6_ANALOG_PMU_REG_CORE);
+ oldtarg = pmureg & IMX6_ANALOG_PMU_REG0_TARG_MASK;
+
+ /* Convert mV to target value. Clamp target to valid range. */
+ if (mv < 725)
+ newtarg = 0x00;
+ else if (mv > 1450)
+ newtarg = 0x1F;
+ else
+ newtarg = (mv - 700) / 25;
+
+ /*
+ * The SOC voltage can't go below 1150mV, and thus because of the 200mV
+ * rule, the ARM voltage can't go below 950mV. The 950 is encoded in
+ * our oppt table, here we handle the SOC 1150 rule as a special case.
+ * (1150-700/25=18).
+ */
+ newtargSoc = (newtarg < 18) ? 18 : newtarg;
+
+ /*
+ * The first time through the 3 voltages might not be equal so use a
+ * long conservative delay. After that we need to delay 3uS for every
+ * 25mV step upward; we actually delay 6uS because empirically, it works
+ * and the 3uS per step recommended by the docs doesn't (3uS fails when
+ * going from 400->1200, but works for smaller changes).
+ */
+ if (init_done) {
+ if (newtarg == oldtarg)
+ return;
+ else if (newtarg > oldtarg)
+ delay = (newtarg - oldtarg) * 6;
+ else
+ delay = 0;
+ } else {
+ delay = (700 / 25) * 6;
+ init_done = true;
+ }
+
+ /*
+ * Make the change and wait for it to take effect.
+ */
+ pmureg &= ~(IMX6_ANALOG_PMU_REG0_TARG_MASK |
+ IMX6_ANALOG_PMU_REG1_TARG_MASK |
+ IMX6_ANALOG_PMU_REG2_TARG_MASK);
+
+ pmureg |= newtarg << IMX6_ANALOG_PMU_REG0_TARG_SHIFT;
+ pmureg |= newtarg << IMX6_ANALOG_PMU_REG1_TARG_SHIFT;
+ pmureg |= newtargSoc << IMX6_ANALOG_PMU_REG2_TARG_SHIFT;
+
+ imx6_anatop_write_4(IMX6_ANALOG_PMU_REG_CORE, pmureg);
+ DELAY(delay);
+ sc->cpu_curmv = newtarg * 25 + 700;
+}
+
+static inline uint32_t
+cpufreq_mhz_from_div(struct imx6_anatop_softc *sc, uint32_t corediv,
+ uint32_t plldiv)
+{
+
+ return ((sc->refosc_mhz * (plldiv / 2)) / (corediv + 1));
+}
+
+static inline void
+cpufreq_mhz_to_div(struct imx6_anatop_softc *sc, uint32_t cpu_mhz,
+ uint32_t *corediv, uint32_t *plldiv)
+{
+
+ *corediv = (cpu_mhz < 650) ? 1 : 0;
+ *plldiv = ((*corediv + 1) * cpu_mhz) / (sc->refosc_mhz / 2);
+}
+
+static inline uint32_t
+cpufreq_actual_mhz(struct imx6_anatop_softc *sc, uint32_t cpu_mhz)
+{
+ uint32_t corediv, plldiv;
+
+ cpufreq_mhz_to_div(sc, cpu_mhz, &corediv, &plldiv);
+ return (cpufreq_mhz_from_div(sc, corediv, plldiv));
+}
+
+static struct oppt *
+cpufreq_nearest_oppt(struct imx6_anatop_softc *sc, uint32_t cpu_newmhz)
+{
+ int d, diff, i, nearest;
+
+ if (cpu_newmhz > sc->cpu_maxmhz_hw && !sc->cpu_overclock_enable)
+ cpu_newmhz = sc->cpu_maxmhz_hw;
+
+ diff = INT_MAX;
+ nearest = 0;
+ for (i = 0; i < nitems(imx6_oppt_table); ++i) {
+ d = abs((int)cpu_newmhz - (int)imx6_oppt_table[i].mhz);
+ if (diff > d) {
+ diff = d;
+ nearest = i;
+ }
+ }
+ return (&imx6_oppt_table[nearest]);
+}
+
+static void
+cpufreq_set_clock(struct imx6_anatop_softc * sc, struct oppt *op)
+{
+ uint32_t corediv, plldiv, timeout, wrk32;
+
+ /* If increasing the frequency, we must first increase the voltage. */
+ if (op->mhz > sc->cpu_curmhz) {
+ vdd_set(sc, op->mv);
+ }
+
+ /*
+ * I can't find a documented procedure for changing the ARM PLL divisor,
+ * but some trial and error came up with this:
+ * - Set the bypass clock source to REF_CLK_24M (source #0).
+ * - Set the PLL into bypass mode; cpu should now be running at 24mhz.
+ * - Change the divisor.
+ * - Wait for the LOCK bit to come on; it takes ~50 loop iterations.
+ * - Turn off bypass mode; cpu should now be running at the new speed.
+ */
+ cpufreq_mhz_to_div(sc, op->mhz, &corediv, &plldiv);
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_ARM_CLR,
+ IMX6_ANALOG_CCM_PLL_ARM_CLK_SRC_MASK);
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_ARM_SET,
+ IMX6_ANALOG_CCM_PLL_ARM_BYPASS);
+
+ wrk32 = imx6_anatop_read_4(IMX6_ANALOG_CCM_PLL_ARM);
+ wrk32 &= ~IMX6_ANALOG_CCM_PLL_ARM_DIV_MASK;
+ wrk32 |= plldiv;
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_ARM, wrk32);
+
+ timeout = 10000;
+ while ((imx6_anatop_read_4(IMX6_ANALOG_CCM_PLL_ARM) &
+ IMX6_ANALOG_CCM_PLL_ARM_LOCK) == 0)
+ if (--timeout == 0)
+ panic("imx6_set_cpu_clock(): PLL never locked");
+
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_ARM_CLR,
+ IMX6_ANALOG_CCM_PLL_ARM_BYPASS);
+ imx_ccm_set_cacrr(corediv);
+
+ /* If lowering the frequency, it is now safe to lower the voltage. */
+ if (op->mhz < sc->cpu_curmhz)
+ vdd_set(sc, op->mv);
+ sc->cpu_curmhz = op->mhz;
+
+ /* Tell the mpcore timer that its frequency has changed. */
+ arm_tmr_change_frequency(
+ cpufreq_actual_mhz(sc, sc->cpu_curmhz) * 1000000 / 2);
+}
+
+static int
+cpufreq_sysctl_minmhz(SYSCTL_HANDLER_ARGS)
+{
+ struct imx6_anatop_softc *sc;
+ struct oppt * op;
+ uint32_t temp;
+ int err;
+
+ sc = arg1;
+
+ temp = sc->cpu_minmhz;
+ err = sysctl_handle_int(oidp, &temp, 0, req);
+ if (err != 0 || req->newptr == NULL)
+ return (err);
+
+ op = cpufreq_nearest_oppt(sc, temp);
+ if (op->mhz > sc->cpu_maxmhz)
+ return (ERANGE);
+ else if (op->mhz == sc->cpu_minmhz)
+ return (0);
+
+ /*
+ * Value changed, update softc. If the new min is higher than the
+ * current speed, raise the current speed to match.
+ */
+ sc->cpu_minmhz = op->mhz;
+ if (sc->cpu_minmhz > sc->cpu_curmhz) {
+ cpufreq_set_clock(sc, op);
+ }
+ return (err);
+}
+
+static int
+cpufreq_sysctl_maxmhz(SYSCTL_HANDLER_ARGS)
+{
+ struct imx6_anatop_softc *sc;
+ struct oppt * op;
+ uint32_t temp;
+ int err;
+
+ sc = arg1;
+
+ temp = sc->cpu_maxmhz;
+ err = sysctl_handle_int(oidp, &temp, 0, req);
+ if (err != 0 || req->newptr == NULL)
+ return (err);
+
+ op = cpufreq_nearest_oppt(sc, temp);
+ if (op->mhz < sc->cpu_minmhz)
+ return (ERANGE);
+ else if (op->mhz == sc->cpu_maxmhz)
+ return (0);
+
+ /*
+ * Value changed, update softc and hardware. The hardware update is
+ * unconditional. We always try to run at max speed, so any change of
+ * the max means we need to change the current speed too, regardless of
+ * whether it is higher or lower than the old max.
+ */
+ sc->cpu_maxmhz = op->mhz;
+ cpufreq_set_clock(sc, op);
+
+ return (err);
+}
+
+static void
+cpufreq_initialize(struct imx6_anatop_softc *sc)
+{
+ uint32_t cfg3speed;
+ struct oppt * op;
+
+ SYSCTL_ADD_INT(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "cpu_mhz", CTLFLAG_RD, &sc->cpu_curmhz, 0,
+ "CPU frequency");
+
+ SYSCTL_ADD_PROC(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "cpu_minmhz",
+ CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_NEEDGIANT,
+ sc, 0, cpufreq_sysctl_minmhz, "IU", "Minimum CPU frequency");
+
+ SYSCTL_ADD_PROC(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "cpu_maxmhz",
+ CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NOFETCH | CTLFLAG_NEEDGIANT,
+ sc, 0, cpufreq_sysctl_maxmhz, "IU", "Maximum CPU frequency");
+
+ SYSCTL_ADD_INT(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "cpu_maxmhz_hw", CTLFLAG_RD, &sc->cpu_maxmhz_hw, 0,
+ "Maximum CPU frequency allowed by hardware");
+
+ SYSCTL_ADD_INT(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "cpu_overclock_enable", CTLFLAG_RWTUN,
+ &sc->cpu_overclock_enable, 0,
+ "Allow setting CPU frequency higher than cpu_maxmhz_hw");
+
+ /*
+ * XXX 24mhz shouldn't be hard-coded, should get this from imx6_ccm
+ * (even though in the real world it will always be 24mhz). Oh wait a
+ * sec, I never wrote imx6_ccm.
+ */
+ sc->refosc_mhz = 24;
+
+ /*
+ * Get the maximum speed this cpu can be set to. The values in the
+ * OCOTP CFG3 register are not documented in the reference manual.
+ * The following info was in an archived email found via web search:
+ * - 2b'11: 1200000000Hz;
+ * - 2b'10: 996000000Hz;
+ * - 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz.
+ * - 2b'00: 792000000Hz;
+ * The default hardware max speed can be overridden by a tunable.
+ */
+ cfg3speed = (fsl_ocotp_read_4(FSL_OCOTP_CFG3) &
+ FSL_OCOTP_CFG3_SPEED_MASK) >> FSL_OCOTP_CFG3_SPEED_SHIFT;
+ sc->cpu_maxmhz_hw = imx6_ocotp_mhz_tab[cfg3speed];
+ sc->cpu_maxmhz = sc->cpu_maxmhz_hw;
+
+ TUNABLE_INT_FETCH("hw.imx6.cpu_minmhz", &sc->cpu_minmhz);
+ op = cpufreq_nearest_oppt(sc, sc->cpu_minmhz);
+ sc->cpu_minmhz = op->mhz;
+ sc->cpu_minmv = op->mv;
+
+ TUNABLE_INT_FETCH("hw.imx6.cpu_maxmhz", &sc->cpu_maxmhz);
+ op = cpufreq_nearest_oppt(sc, sc->cpu_maxmhz);
+ sc->cpu_maxmhz = op->mhz;
+ sc->cpu_maxmv = op->mv;
+
+ /*
+ * Set the CPU to maximum speed.
+ *
+ * We won't have thermal throttling until interrupts are enabled, but we
+ * want to run at full speed through all the device init stuff. This
+ * basically assumes that a single core can't overheat before interrupts
+ * are enabled; empirical testing shows that to be a safe assumption.
+ */
+ cpufreq_set_clock(sc, op);
+}
+
+static inline uint32_t
+temp_from_count(struct imx6_anatop_softc *sc, uint32_t count)
+{
+
+ return (((sc->temp_high_val - (count - sc->temp_high_cnt) *
+ (sc->temp_high_val - 250) /
+ (sc->temp_room_cnt - sc->temp_high_cnt))));
+}
+
+static inline uint32_t
+temp_to_count(struct imx6_anatop_softc *sc, uint32_t temp)
+{
+
+ return ((sc->temp_room_cnt - sc->temp_high_cnt) *
+ (sc->temp_high_val - temp) / (sc->temp_high_val - 250) +
+ sc->temp_high_cnt);
+}
+
+static void
+temp_update_count(struct imx6_anatop_softc *sc)
+{
+ uint32_t val;
+
+ val = imx6_anatop_read_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0);
+ if (!(val & IMX6_ANALOG_TEMPMON_TEMPSENSE0_VALID))
+ return;
+ sc->temp_last_cnt =
+ (val & IMX6_ANALOG_TEMPMON_TEMPSENSE0_TEMP_CNT_MASK) >>
+ IMX6_ANALOG_TEMPMON_TEMPSENSE0_TEMP_CNT_SHIFT;
+}
+
+static int
+temp_sysctl_handler(SYSCTL_HANDLER_ARGS)
+{
+ struct imx6_anatop_softc *sc = arg1;
+ uint32_t t;
+
+ temp_update_count(sc);
+
+ t = temp_from_count(sc, sc->temp_last_cnt) + TZ_ZEROC;
+
+ return (sysctl_handle_int(oidp, &t, 0, req));
+}
+
+static int
+temp_throttle_sysctl_handler(SYSCTL_HANDLER_ARGS)
+{
+ struct imx6_anatop_softc *sc = arg1;
+ int err;
+ uint32_t temp;
+
+ temp = sc->temp_throttle_val + TZ_ZEROC;
+ err = sysctl_handle_int(oidp, &temp, 0, req);
+ if (temp < TZ_ZEROC)
+ return (ERANGE);
+ temp -= TZ_ZEROC;
+ if (err != 0 || req->newptr == NULL || temp == sc->temp_throttle_val)
+ return (err);
+
+ /* Value changed, update counts in softc and hardware. */
+ sc->temp_throttle_val = temp;
+ sc->temp_throttle_trigger_cnt = temp_to_count(sc, sc->temp_throttle_val);
+ sc->temp_throttle_reset_cnt = temp_to_count(sc, sc->temp_throttle_val - 100);
+ imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0_CLR,
+ IMX6_ANALOG_TEMPMON_TEMPSENSE0_ALARM_MASK);
+ imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0_SET,
+ (sc->temp_throttle_trigger_cnt <<
+ IMX6_ANALOG_TEMPMON_TEMPSENSE0_ALARM_SHIFT));
+ return (err);
+}
+
+static void
+tempmon_gofast(struct imx6_anatop_softc *sc)
+{
+
+ if (sc->cpu_curmhz < sc->cpu_maxmhz) {
+ cpufreq_set_clock(sc, cpufreq_nearest_oppt(sc, sc->cpu_maxmhz));
+ }
+}
+
+static void
+tempmon_goslow(struct imx6_anatop_softc *sc)
+{
+
+ if (sc->cpu_curmhz > sc->cpu_minmhz) {
+ cpufreq_set_clock(sc, cpufreq_nearest_oppt(sc, sc->cpu_minmhz));
+ }
+}
+
+static int
+tempmon_intr(void *arg)
+{
+ struct imx6_anatop_softc *sc = arg;
+
+ /*
+ * XXX Note that this code doesn't currently run (for some mysterious
+ * reason we just never get an interrupt), so the real monitoring is
+ * done by tempmon_throttle_check().
+ */
+ tempmon_goslow(sc);
+ /* XXX Schedule callout to speed back up eventually. */
+ return (FILTER_HANDLED);
+}
+
+static void
+tempmon_throttle_check(void *arg)
+{
+ struct imx6_anatop_softc *sc = arg;
+
+ /* Lower counts are higher temperatures. */
+ if (sc->temp_last_cnt < sc->temp_throttle_trigger_cnt)
+ tempmon_goslow(sc);
+ else if (sc->temp_last_cnt > (sc->temp_throttle_reset_cnt))
+ tempmon_gofast(sc);
+
+ callout_reset_sbt(&sc->temp_throttle_callout, sc->temp_throttle_delay,
+ 0, tempmon_throttle_check, sc, 0);
+
+}
+
+static void
+initialize_tempmon(struct imx6_anatop_softc *sc)
+{
+ uint32_t cal;
+
+ /*
+ * Fetch calibration data: a sensor count at room temperature (25C),
+ * a sensor count at a high temperature, and that temperature
+ */
+ cal = fsl_ocotp_read_4(FSL_OCOTP_ANA1);
+ sc->temp_room_cnt = (cal & 0xFFF00000) >> 20;
+ sc->temp_high_cnt = (cal & 0x000FFF00) >> 8;
+ sc->temp_high_val = (cal & 0x000000FF) * 10;
+
+ /*
+ * Throttle to a lower cpu freq at 10C below the "hot" temperature, and
+ * reset back to max cpu freq at 5C below the trigger.
+ */
+ sc->temp_throttle_val = sc->temp_high_val - 100;
+ sc->temp_throttle_trigger_cnt =
+ temp_to_count(sc, sc->temp_throttle_val);
+ sc->temp_throttle_reset_cnt =
+ temp_to_count(sc, sc->temp_throttle_val - 50);
+
+ /*
+ * Set the sensor to sample automatically at 16Hz (32.768KHz/0x800), set
+ * the throttle count, and begin making measurements.
+ */
+ imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE1, 0x0800);
+ imx6_anatop_write_4(IMX6_ANALOG_TEMPMON_TEMPSENSE0,
+ (sc->temp_throttle_trigger_cnt <<
+ IMX6_ANALOG_TEMPMON_TEMPSENSE0_ALARM_SHIFT) |
+ IMX6_ANALOG_TEMPMON_TEMPSENSE0_MEASURE);
+
+ /*
+ * XXX Note that the alarm-interrupt feature isn't working yet, so
+ * we'll use a callout handler to check at 10Hz. Make sure we have an
+ * initial temperature reading before starting up the callouts so we
+ * don't get a bogus reading of zero.
+ */
+ while (sc->temp_last_cnt == 0)
+ temp_update_count(sc);
+ sc->temp_throttle_delay = 100 * SBT_1MS;
+ callout_init(&sc->temp_throttle_callout, 0);
+ callout_reset_sbt(&sc->temp_throttle_callout, sc->temp_throttle_delay,
+ 0, tempmon_throttle_check, sc, 0);
+
+ SYSCTL_ADD_PROC(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "temperature",
+ CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_NEEDGIANT, sc, 0,
+ temp_sysctl_handler, "IK", "Current die temperature");
+ SYSCTL_ADD_PROC(NULL, SYSCTL_STATIC_CHILDREN(_hw_imx),
+ OID_AUTO, "throttle_temperature",
+ CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc,
+ 0, temp_throttle_sysctl_handler, "IK",
+ "Throttle CPU when exceeding this temperature");
+}
+
+static void
+intr_setup(void *arg)
+{
+ int rid;
+ struct imx6_anatop_softc *sc;
+
+ sc = arg;
+ rid = 0;
+ sc->res[IRQRES] = bus_alloc_resource_any(sc->dev, SYS_RES_IRQ, &rid,
+ RF_ACTIVE);
+ if (sc->res[IRQRES] != NULL) {
+ bus_setup_intr(sc->dev, sc->res[IRQRES],
+ INTR_TYPE_MISC | INTR_MPSAFE, tempmon_intr, NULL, sc,
+ &sc->temp_intrhand);
+ } else {
+ device_printf(sc->dev, "Cannot allocate IRQ resource\n");
+ }
+ config_intrhook_disestablish(&sc->intr_setup_hook);
+}
+
+static void
+imx6_anatop_new_pass(device_t dev)
+{
+ struct imx6_anatop_softc *sc;
+ const int cpu_init_pass = BUS_PASS_CPU + BUS_PASS_ORDER_MIDDLE;
+
+ /*
+ * We attach during BUS_PASS_BUS (because some day we will be a
+ * simplebus that has regulator devices as children), but some of our
+ * init work cannot be done until BUS_PASS_CPU (we rely on other devices
+ * that attach on the CPU pass).
+ */
+ sc = device_get_softc(dev);
+ if (!sc->cpu_init_done && bus_current_pass >= cpu_init_pass) {
+ sc->cpu_init_done = true;
+ cpufreq_initialize(sc);
+ initialize_tempmon(sc);
+ if (bootverbose) {
+ device_printf(sc->dev, "CPU %uMHz @ %umV\n",
+ sc->cpu_curmhz, sc->cpu_curmv);
+ }
+ }
+ bus_generic_new_pass(dev);
+}
+
+static int
+imx6_anatop_detach(device_t dev)
+{
+
+ /* This device can never detach. */
+ return (EBUSY);
+}
+
+static int
+imx6_anatop_attach(device_t dev)
+{
+ struct imx6_anatop_softc *sc;
+ int err;
+
+ sc = device_get_softc(dev);
+ sc->dev = dev;
+
+ /* Allocate bus_space resources. */
+ if (bus_alloc_resources(dev, imx6_anatop_spec, sc->res)) {
+ device_printf(dev, "Cannot allocate resources\n");
+ err = ENXIO;
+ goto out;
+ }
+
+ sc->intr_setup_hook.ich_func = intr_setup;
+ sc->intr_setup_hook.ich_arg = sc;
+ config_intrhook_establish(&sc->intr_setup_hook);
+
+ SYSCTL_ADD_UINT(device_get_sysctl_ctx(sc->dev),
+ SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)),
+ OID_AUTO, "cpu_voltage", CTLFLAG_RD,
+ &sc->cpu_curmv, 0, "Current CPU voltage in millivolts");
+
+ imx6_anatop_sc = sc;
+
+ /*
+ * Other code seen on the net sets this SELFBIASOFF flag around the same
+ * time the temperature sensor is set up, although it's unclear how the
+ * two are related (if at all).
+ */
+ imx6_anatop_write_4(IMX6_ANALOG_PMU_MISC0_SET,
+ IMX6_ANALOG_PMU_MISC0_SELFBIASOFF);
+
+ /*
+ * Some day, when we're ready to deal with the actual anatop regulators
+ * that are described in fdt data as children of this "bus", this would
+ * be the place to invoke a simplebus helper routine to instantiate the
+ * children from the fdt data.
+ */
+
+ err = 0;
+
+out:
+
+ if (err != 0) {
+ bus_release_resources(dev, imx6_anatop_spec, sc->res);
+ }
+
+ return (err);
+}
+
+uint32_t
+pll4_configure_output(uint32_t mfi, uint32_t mfn, uint32_t mfd)
+{
+ int reg;
+
+ /*
+ * Audio PLL (PLL4).
+ * PLL output frequency = Fref * (DIV_SELECT + NUM/DENOM)
+ */
+
+ reg = (IMX6_ANALOG_CCM_PLL_AUDIO_ENABLE);
+ reg &= ~(IMX6_ANALOG_CCM_PLL_AUDIO_DIV_SELECT_MASK << \
+ IMX6_ANALOG_CCM_PLL_AUDIO_DIV_SELECT_SHIFT);
+ reg |= (mfi << IMX6_ANALOG_CCM_PLL_AUDIO_DIV_SELECT_SHIFT);
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_AUDIO, reg);
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_AUDIO_NUM, mfn);
+ imx6_anatop_write_4(IMX6_ANALOG_CCM_PLL_AUDIO_DENOM, mfd);
+
+ return (0);
+}
+
+static int
+imx6_anatop_probe(device_t dev)
+{
+
+ if (!ofw_bus_status_okay(dev))
+ return (ENXIO);
+
+ if (ofw_bus_is_compatible(dev, "fsl,imx6q-anatop") == 0)
+ return (ENXIO);
+
+ device_set_desc(dev, "Freescale i.MX6 Analog PLLs and Power");
+
+ return (BUS_PROBE_DEFAULT);
+}
+
+uint32_t
+imx6_get_cpu_clock(void)
+{
+ uint32_t corediv, plldiv;
+
+ corediv = imx_ccm_get_cacrr();
+ plldiv = imx6_anatop_read_4(IMX6_ANALOG_CCM_PLL_ARM) &
+ IMX6_ANALOG_CCM_PLL_ARM_DIV_MASK;
+ return (cpufreq_mhz_from_div(imx6_anatop_sc, corediv, plldiv));
+}
+
+static device_method_t imx6_anatop_methods[] = {
+ /* Device interface */
+ DEVMETHOD(device_probe, imx6_anatop_probe),
+ DEVMETHOD(device_attach, imx6_anatop_attach),
+ DEVMETHOD(device_detach, imx6_anatop_detach),
+
+ /* Bus interface */
+ DEVMETHOD(bus_new_pass, imx6_anatop_new_pass),
+
+ DEVMETHOD_END
+};
+
+static driver_t imx6_anatop_driver = {
+ "imx6_anatop",
+ imx6_anatop_methods,
+ sizeof(struct imx6_anatop_softc)
+};
+
+static devclass_t imx6_anatop_devclass;
+
+EARLY_DRIVER_MODULE(imx6_anatop, simplebus, imx6_anatop_driver,
+ imx6_anatop_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
+EARLY_DRIVER_MODULE(imx6_anatop, ofwbus, imx6_anatop_driver,
+ imx6_anatop_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);