/*- * Copyright (c) 2013 Oleksandr Tymoshenko * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "pwmbus_if.h" #include "am335x_pwm.h" /******************************************************************************* * Enhanced resolution PWM driver. Many of the advanced featues of the hardware * are not supported by this driver. What is implemented here is simple * variable-duty-cycle PWM output. ******************************************************************************/ /* In ticks */ #define DEFAULT_PWM_PERIOD 1000 #define PWM_CLOCK 100000000UL #define NS_PER_SEC 1000000000 #define PWM_LOCK(_sc) mtx_lock(&(_sc)->sc_mtx) #define PWM_UNLOCK(_sc) mtx_unlock(&(_sc)->sc_mtx) #define PWM_LOCK_ASSERT(_sc) mtx_assert(&(_sc)->sc_mtx, MA_OWNED) #define PWM_LOCK_INIT(_sc) mtx_init(&(_sc)->sc_mtx, \ device_get_nameunit(_sc->sc_dev), "am335x_ehrpwm softc", MTX_DEF) #define PWM_LOCK_DESTROY(_sc) mtx_destroy(&(_sc)->sc_mtx) #define EPWM_READ2(_sc, reg) bus_read_2((_sc)->sc_mem_res, reg) #define EPWM_WRITE2(_sc, reg, value) \ bus_write_2((_sc)->sc_mem_res, reg, value) #define EPWM_TBCTL 0x00 /* see 15.2.2.11 for the first two, used in debug situations */ #define TBCTL_FREERUN_STOP_NEXT_TBC_INCREMENT (0 << 14) #define TBCTL_FREERUN_STOP_COMPLETE_CYCLE (1 << 14) /* ignore suspend control signal */ #define TBCTL_FREERUN (2 << 14) #define TBCTL_PHDIR_UP (1 << 13) #define TBCTL_PHDIR_DOWN (0 << 13) #define TBCTL_CLKDIV(x) ((x) << 10) #define TBCTL_CLKDIV_MASK (7 << 10) #define TBCTL_HSPCLKDIV(x) ((x) << 7) #define TBCTL_HSPCLKDIV_MASK (7 << 7) #define TBCTL_SYNCOSEL_DISABLED (3 << 4) #define TBCTL_PRDLD_SHADOW (0 << 3) #define TBCTL_PRDLD_IMMEDIATE (1 << 3) #define TBCTL_PHSEN_DISABLED (0 << 2) #define TBCTL_PHSEN_ENABLED (1 << 2) #define TBCTL_CTRMODE_MASK (3) #define TBCTL_CTRMODE_UP (0 << 0) #define TBCTL_CTRMODE_DOWN (1 << 0) #define TBCTL_CTRMODE_UPDOWN (2 << 0) #define TBCTL_CTRMODE_FREEZE (3 << 0) #define EPWM_TBSTS 0x02 #define EPWM_TBPHSHR 0x04 #define EPWM_TBPHS 0x06 #define EPWM_TBCNT 0x08 #define EPWM_TBPRD 0x0a /* Counter-compare */ #define EPWM_CMPCTL 0x0e #define CMPCTL_SHDWBMODE_SHADOW (1 << 6) #define CMPCTL_SHDWBMODE_IMMEDIATE (0 << 6) #define CMPCTL_SHDWAMODE_SHADOW (1 << 4) #define CMPCTL_SHDWAMODE_IMMEDIATE (0 << 4) #define CMPCTL_LOADBMODE_ZERO (0 << 2) #define CMPCTL_LOADBMODE_PRD (1 << 2) #define CMPCTL_LOADBMODE_EITHER (2 << 2) #define CMPCTL_LOADBMODE_FREEZE (3 << 2) #define CMPCTL_LOADAMODE_ZERO (0 << 0) #define CMPCTL_LOADAMODE_PRD (1 << 0) #define CMPCTL_LOADAMODE_EITHER (2 << 0) #define CMPCTL_LOADAMODE_FREEZE (3 << 0) #define EPWM_CMPAHR 0x10 #define EPWM_CMPA 0x12 #define EPWM_CMPB 0x14 /* CMPCTL_LOADAMODE_ZERO */ #define EPWM_AQCTLA 0x16 #define EPWM_AQCTLB 0x18 #define AQCTL_CBU_NONE (0 << 8) #define AQCTL_CBU_CLEAR (1 << 8) #define AQCTL_CBU_SET (2 << 8) #define AQCTL_CBU_TOGGLE (3 << 8) #define AQCTL_CAU_NONE (0 << 4) #define AQCTL_CAU_CLEAR (1 << 4) #define AQCTL_CAU_SET (2 << 4) #define AQCTL_CAU_TOGGLE (3 << 4) #define AQCTL_ZRO_NONE (0 << 0) #define AQCTL_ZRO_CLEAR (1 << 0) #define AQCTL_ZRO_SET (2 << 0) #define AQCTL_ZRO_TOGGLE (3 << 0) #define EPWM_AQSFRC 0x1a #define EPWM_AQCSFRC 0x1c #define AQCSFRC_OFF 0 #define AQCSFRC_LO 1 #define AQCSFRC_HI 2 #define AQCSFRC_MASK 3 #define AQCSFRC(chan, hilo) ((hilo) << (2 * chan)) /* Trip-Zone module */ #define EPWM_TZSEL 0x24 #define EPWM_TZCTL 0x28 #define EPWM_TZFLG 0x2C /* Dead band */ #define EPWM_DBCTL 0x1E #define DBCTL_MASK (3 << 0) #define DBCTL_BYPASS 0 #define DBCTL_RISING_EDGE 1 #define DBCTL_FALLING_EDGE 2 #define DBCTL_BOTH_EDGE 3 /* PWM-chopper */ #define EPWM_PCCTL 0x3C #define PCCTL_CHPEN_MASK (1 << 0) #define PCCTL_CHPEN_DISABLE 0 #define PCCTL_CHPEN_ENABLE 1 /* High-Resolution PWM */ #define EPWM_HRCTL 0x40 #define HRCTL_DELMODE_BOTH 3 #define HRCTL_DELMODE_FALL 2 #define HRCTL_DELMODE_RISE 1 static device_probe_t am335x_ehrpwm_probe; static device_attach_t am335x_ehrpwm_attach; static device_detach_t am335x_ehrpwm_detach; struct ehrpwm_channel { u_int duty; /* on duration, in ns */ bool enabled; /* channel enabled? */ bool inverted; /* signal inverted? */ }; #define NUM_CHANNELS 2 struct am335x_ehrpwm_softc { device_t sc_dev; device_t sc_busdev; struct mtx sc_mtx; struct resource *sc_mem_res; int sc_mem_rid; /* Things used for configuration via pwm(9) api. */ u_int sc_clkfreq; /* frequency in Hz */ u_int sc_clktick; /* duration in ns */ u_int sc_period; /* duration in ns */ struct ehrpwm_channel sc_channels[NUM_CHANNELS]; }; static struct ofw_compat_data compat_data[] = { {"ti,am3352-ehrpwm", true}, {"ti,am33xx-ehrpwm", true}, {NULL, false}, }; SIMPLEBUS_PNP_INFO(compat_data); static void am335x_ehrpwm_cfg_duty(struct am335x_ehrpwm_softc *sc, u_int chan, u_int duty) { u_int tbcmp; if (duty == 0) tbcmp = 0; else tbcmp = max(1, duty / sc->sc_clktick); sc->sc_channels[chan].duty = tbcmp * sc->sc_clktick; PWM_LOCK_ASSERT(sc); EPWM_WRITE2(sc, (chan == 0) ? EPWM_CMPA : EPWM_CMPB, tbcmp); } static void am335x_ehrpwm_cfg_enable(struct am335x_ehrpwm_softc *sc, u_int chan, bool enable) { uint16_t regval; sc->sc_channels[chan].enabled = enable; /* * Turn off any existing software-force of the channel, then force * it in the right direction (high or low) if it's not being enabled. */ PWM_LOCK_ASSERT(sc); regval = EPWM_READ2(sc, EPWM_AQCSFRC); regval &= ~AQCSFRC(chan, AQCSFRC_MASK); if (!sc->sc_channels[chan].enabled) { if (sc->sc_channels[chan].inverted) regval |= AQCSFRC(chan, AQCSFRC_HI); else regval |= AQCSFRC(chan, AQCSFRC_LO); } EPWM_WRITE2(sc, EPWM_AQCSFRC, regval); } static bool am335x_ehrpwm_cfg_period(struct am335x_ehrpwm_softc *sc, u_int period) { uint16_t regval; u_int clkdiv, hspclkdiv, pwmclk, pwmtick, tbprd; /* Can't do a period shorter than 2 clock ticks. */ if (period < 2 * NS_PER_SEC / PWM_CLOCK) { sc->sc_clkfreq = 0; sc->sc_clktick = 0; sc->sc_period = 0; return (false); } /* * Figure out how much we have to divide down the base 100MHz clock so * that we can express the requested period as a 16-bit tick count. */ tbprd = 0; for (clkdiv = 0; clkdiv < 8; ++clkdiv) { const u_int cd = 1 << clkdiv; for (hspclkdiv = 0; hspclkdiv < 8; ++hspclkdiv) { const u_int cdhs = max(1, hspclkdiv * 2); pwmclk = PWM_CLOCK / (cd * cdhs); pwmtick = NS_PER_SEC / pwmclk; if (period / pwmtick < 65536) { tbprd = period / pwmtick; break; } } if (tbprd != 0) break; } /* Handle requested period too long for available clock divisors. */ if (tbprd == 0) return (false); /* * If anything has changed from the current settings, reprogram the * clock divisors and period register. */ if (sc->sc_clkfreq != pwmclk || sc->sc_clktick != pwmtick || sc->sc_period != tbprd * pwmtick) { sc->sc_clkfreq = pwmclk; sc->sc_clktick = pwmtick; sc->sc_period = tbprd * pwmtick; PWM_LOCK_ASSERT(sc); regval = EPWM_READ2(sc, EPWM_TBCTL); regval &= ~(TBCTL_CLKDIV_MASK | TBCTL_HSPCLKDIV_MASK); regval |= TBCTL_CLKDIV(clkdiv) | TBCTL_HSPCLKDIV(hspclkdiv); EPWM_WRITE2(sc, EPWM_TBCTL, regval); EPWM_WRITE2(sc, EPWM_TBPRD, tbprd - 1); #if 0 device_printf(sc->sc_dev, "clkdiv %u hspclkdiv %u tbprd %u " "clkfreq %u Hz clktick %u ns period got %u requested %u\n", clkdiv, hspclkdiv, tbprd - 1, sc->sc_clkfreq, sc->sc_clktick, sc->sc_period, period); #endif /* * If the period changed, that invalidates the current CMP * registers (duty values), just zero them out. */ am335x_ehrpwm_cfg_duty(sc, 0, 0); am335x_ehrpwm_cfg_duty(sc, 1, 0); } return (true); } static int am335x_ehrpwm_channel_count(device_t dev, u_int *nchannel) { *nchannel = NUM_CHANNELS; return (0); } static int am335x_ehrpwm_channel_config(device_t dev, u_int channel, u_int period, u_int duty) { struct am335x_ehrpwm_softc *sc; bool status; if (channel >= NUM_CHANNELS) return (EINVAL); sc = device_get_softc(dev); PWM_LOCK(sc); status = am335x_ehrpwm_cfg_period(sc, period); if (status) am335x_ehrpwm_cfg_duty(sc, channel, duty); PWM_UNLOCK(sc); return (status ? 0 : EINVAL); } static int am335x_ehrpwm_channel_get_config(device_t dev, u_int channel, u_int *period, u_int *duty) { struct am335x_ehrpwm_softc *sc; if (channel >= NUM_CHANNELS) return (EINVAL); sc = device_get_softc(dev); *period = sc->sc_period; *duty = sc->sc_channels[channel].duty; return (0); } static int am335x_ehrpwm_channel_set_flags(device_t dev, u_int channel, uint32_t flags) { struct am335x_ehrpwm_softc *sc; if (channel >= NUM_CHANNELS) return (EINVAL); sc = device_get_softc(dev); PWM_LOCK(sc); if (flags & PWM_POLARITY_INVERTED) { sc->sc_channels[channel].inverted = true; /* Action-Qualifier 15.2.2.5 */ if (channel == 0) EPWM_WRITE2(sc, EPWM_AQCTLA, (AQCTL_ZRO_CLEAR | AQCTL_CAU_SET)); else EPWM_WRITE2(sc, EPWM_AQCTLB, (AQCTL_ZRO_CLEAR | AQCTL_CBU_SET)); } else { sc->sc_channels[channel].inverted = false; if (channel == 0) EPWM_WRITE2(sc, EPWM_AQCTLA, (AQCTL_ZRO_SET | AQCTL_CAU_CLEAR)); else EPWM_WRITE2(sc, EPWM_AQCTLB, (AQCTL_ZRO_SET | AQCTL_CBU_CLEAR)); } PWM_UNLOCK(sc); return (0); } static int am335x_ehrpwm_channel_get_flags(device_t dev, u_int channel, uint32_t *flags) { struct am335x_ehrpwm_softc *sc; if (channel >= NUM_CHANNELS) return (EINVAL); sc = device_get_softc(dev); if (sc->sc_channels[channel].inverted == true) *flags = PWM_POLARITY_INVERTED; else *flags = 0; return (0); } static int am335x_ehrpwm_channel_enable(device_t dev, u_int channel, bool enable) { struct am335x_ehrpwm_softc *sc; if (channel >= NUM_CHANNELS) return (EINVAL); sc = device_get_softc(dev); PWM_LOCK(sc); am335x_ehrpwm_cfg_enable(sc, channel, enable); PWM_UNLOCK(sc); return (0); } static int am335x_ehrpwm_channel_is_enabled(device_t dev, u_int channel, bool *enabled) { struct am335x_ehrpwm_softc *sc; if (channel >= NUM_CHANNELS) return (EINVAL); sc = device_get_softc(dev); *enabled = sc->sc_channels[channel].enabled; return (0); } static int am335x_ehrpwm_probe(device_t dev) { if (!ofw_bus_status_okay(dev)) return (ENXIO); if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data) return (ENXIO); device_set_desc(dev, "AM335x EHRPWM"); return (BUS_PROBE_DEFAULT); } static int am335x_ehrpwm_attach(device_t dev) { struct am335x_ehrpwm_softc *sc; uint16_t reg; sc = device_get_softc(dev); sc->sc_dev = dev; PWM_LOCK_INIT(sc); sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &sc->sc_mem_rid, RF_ACTIVE); if (sc->sc_mem_res == NULL) { device_printf(dev, "cannot allocate memory resources\n"); goto fail; } /* CONFIGURE EPWM */ reg = EPWM_READ2(sc, EPWM_TBCTL); reg &= ~(TBCTL_CLKDIV_MASK | TBCTL_HSPCLKDIV_MASK); EPWM_WRITE2(sc, EPWM_TBCTL, reg); EPWM_WRITE2(sc, EPWM_TBPRD, DEFAULT_PWM_PERIOD - 1); EPWM_WRITE2(sc, EPWM_CMPA, 0); EPWM_WRITE2(sc, EPWM_CMPB, 0); /* Action-Qualifier 15.2.2.5 */ EPWM_WRITE2(sc, EPWM_AQCTLA, (AQCTL_ZRO_SET | AQCTL_CAU_CLEAR)); EPWM_WRITE2(sc, EPWM_AQCTLB, (AQCTL_ZRO_SET | AQCTL_CBU_CLEAR)); /* Dead band 15.2.2.6 */ reg = EPWM_READ2(sc, EPWM_DBCTL); reg &= ~DBCTL_MASK; reg |= DBCTL_BYPASS; EPWM_WRITE2(sc, EPWM_DBCTL, reg); /* PWM-chopper described in 15.2.2.7 */ /* Acc. TRM used in pulse transformerbased gate drivers * to control the power switching-elements */ reg = EPWM_READ2(sc, EPWM_PCCTL); reg &= ~PCCTL_CHPEN_MASK; reg |= PCCTL_CHPEN_DISABLE; EPWM_WRITE2(sc, EPWM_PCCTL, PCCTL_CHPEN_DISABLE); /* Trip zone are described in 15.2.2.8. * Essential its used to detect faults and can be configured * to react on such faults.. */ /* disable TZn as one-shot / CVC trip source 15.2.4.18 */ EPWM_WRITE2(sc, EPWM_TZSEL, 0x0); /* reg described in 15.2.4.19 */ EPWM_WRITE2(sc, EPWM_TZCTL, 0xf); reg = EPWM_READ2(sc, EPWM_TZFLG); /* START EPWM */ reg &= ~TBCTL_CTRMODE_MASK; reg |= TBCTL_CTRMODE_UP | TBCTL_FREERUN; EPWM_WRITE2(sc, EPWM_TBCTL, reg); if ((sc->sc_busdev = device_add_child(dev, "pwmbus", -1)) == NULL) { device_printf(dev, "Cannot add child pwmbus\n"); // This driver can still do things even without the bus child. } bus_generic_probe(dev); return (bus_generic_attach(dev)); fail: PWM_LOCK_DESTROY(sc); if (sc->sc_mem_res) bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_mem_rid, sc->sc_mem_res); return(ENXIO); } static int am335x_ehrpwm_detach(device_t dev) { struct am335x_ehrpwm_softc *sc; int error; sc = device_get_softc(dev); if ((error = bus_generic_detach(sc->sc_dev)) != 0) return (error); PWM_LOCK(sc); if (sc->sc_busdev != NULL) device_delete_child(dev, sc->sc_busdev); if (sc->sc_mem_res) bus_release_resource(dev, SYS_RES_MEMORY, sc->sc_mem_rid, sc->sc_mem_res); PWM_UNLOCK(sc); PWM_LOCK_DESTROY(sc); return (0); } static phandle_t am335x_ehrpwm_get_node(device_t bus, device_t dev) { /* * Share our controller node with our pwmbus child; it instantiates * devices by walking the children contained within our node. */ return ofw_bus_get_node(bus); } static device_method_t am335x_ehrpwm_methods[] = { DEVMETHOD(device_probe, am335x_ehrpwm_probe), DEVMETHOD(device_attach, am335x_ehrpwm_attach), DEVMETHOD(device_detach, am335x_ehrpwm_detach), /* ofw_bus_if */ DEVMETHOD(ofw_bus_get_node, am335x_ehrpwm_get_node), /* pwm interface */ DEVMETHOD(pwmbus_channel_count, am335x_ehrpwm_channel_count), DEVMETHOD(pwmbus_channel_config, am335x_ehrpwm_channel_config), DEVMETHOD(pwmbus_channel_get_config, am335x_ehrpwm_channel_get_config), DEVMETHOD(pwmbus_channel_set_flags, am335x_ehrpwm_channel_set_flags), DEVMETHOD(pwmbus_channel_get_flags, am335x_ehrpwm_channel_get_flags), DEVMETHOD(pwmbus_channel_enable, am335x_ehrpwm_channel_enable), DEVMETHOD(pwmbus_channel_is_enabled, am335x_ehrpwm_channel_is_enabled), DEVMETHOD_END }; static driver_t am335x_ehrpwm_driver = { "pwm", am335x_ehrpwm_methods, sizeof(struct am335x_ehrpwm_softc), }; DRIVER_MODULE(am335x_ehrpwm, am335x_pwmss, am335x_ehrpwm_driver, 0, 0); MODULE_VERSION(am335x_ehrpwm, 1); MODULE_DEPEND(am335x_ehrpwm, am335x_pwmss, 1, 1, 1); MODULE_DEPEND(am335x_ehrpwm, pwmbus, 1, 1, 1);