/* * Copyright (c) 2014 The DragonFly Project. All rights reserved. * * This code is derived from software contributed to The DragonFly Project * by Matthew Dillon and was subsequently ported * to FreeBSD by Michael Gmelin * * 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. * 3. Neither the name of The DragonFly Project nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific, prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 * COPYRIGHT HOLDERS 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 __FBSDID("$FreeBSD$"); /* * Intel fourth generation mobile cpus integrated I2C device. * * See ig4_reg.h for datasheet reference and notes. * See ig4_var.h for locking semantics. */ #include "opt_acpi.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef DEV_ACPI #include #include #include #endif #include #include #include #include #define DO_POLL(sc) (cold || kdb_active || SCHEDULER_STOPPED() || sc->poll) /* * tLOW, tHIGH periods of the SCL clock and maximal falling time of both * lines are taken from I2C specifications. */ #define IG4_SPEED_STD_THIGH 4000 /* nsec */ #define IG4_SPEED_STD_TLOW 4700 /* nsec */ #define IG4_SPEED_STD_TF_MAX 300 /* nsec */ #define IG4_SPEED_FAST_THIGH 600 /* nsec */ #define IG4_SPEED_FAST_TLOW 1300 /* nsec */ #define IG4_SPEED_FAST_TF_MAX 300 /* nsec */ /* * Ig4 hardware parameters except Haswell are taken from intel_lpss driver */ static const struct ig4_hw ig4iic_hw[] = { [IG4_HASWELL] = { .ic_clock_rate = 100, /* MHz */ .sda_hold_time = 90, /* nsec */ .txfifo_depth = 32, .rxfifo_depth = 32, }, [IG4_ATOM] = { .ic_clock_rate = 100, .sda_fall_time = 280, .scl_fall_time = 240, .sda_hold_time = 60, .txfifo_depth = 32, .rxfifo_depth = 32, }, [IG4_SKYLAKE] = { .ic_clock_rate = 120, .sda_hold_time = 230, }, [IG4_APL] = { .ic_clock_rate = 133, .sda_fall_time = 171, .scl_fall_time = 208, .sda_hold_time = 207, }, [IG4_CANNONLAKE] = { .ic_clock_rate = 216, .sda_hold_time = 230, }, [IG4_TIGERLAKE] = { .ic_clock_rate = 133, .sda_fall_time = 171, .scl_fall_time = 208, .sda_hold_time = 42, }, [IG4_GEMINILAKE] = { .ic_clock_rate = 133, .sda_fall_time = 171, .scl_fall_time = 290, .sda_hold_time = 313, }, }; static int ig4iic_set_config(ig4iic_softc_t *sc, bool reset); static driver_filter_t ig4iic_intr; static void ig4iic_dump(ig4iic_softc_t *sc); static int ig4_dump; SYSCTL_INT(_debug, OID_AUTO, ig4_dump, CTLFLAG_RW, &ig4_dump, 0, "Dump controller registers"); /* * Clock registers initialization control * 0 - Try read clock registers from ACPI and fallback to p.1. * 1 - Calculate values based on controller type (IC clock rate). * 2 - Use values inherited from DragonflyBSD driver (old behavior). * 3 - Keep clock registers intact. */ static int ig4_timings; SYSCTL_INT(_debug, OID_AUTO, ig4_timings, CTLFLAG_RDTUN, &ig4_timings, 0, "Controller timings 0=ACPI, 1=predefined, 2=legacy, 3=do not change"); /* * Low-level inline support functions */ static __inline void reg_write(ig4iic_softc_t *sc, uint32_t reg, uint32_t value) { bus_write_4(sc->regs_res, reg, value); bus_barrier(sc->regs_res, reg, 4, BUS_SPACE_BARRIER_WRITE); } static __inline uint32_t reg_read(ig4iic_softc_t *sc, uint32_t reg) { uint32_t value; bus_barrier(sc->regs_res, reg, 4, BUS_SPACE_BARRIER_READ); value = bus_read_4(sc->regs_res, reg); return (value); } static void ig4iic_set_intr_mask(ig4iic_softc_t *sc, uint32_t val) { if (sc->intr_mask != val) { reg_write(sc, IG4_REG_INTR_MASK, val); sc->intr_mask = val; } } static int intrstat2iic(ig4iic_softc_t *sc, uint32_t val) { uint32_t src; if (val & IG4_INTR_RX_UNDER) reg_read(sc, IG4_REG_CLR_RX_UNDER); if (val & IG4_INTR_RX_OVER) reg_read(sc, IG4_REG_CLR_RX_OVER); if (val & IG4_INTR_TX_OVER) reg_read(sc, IG4_REG_CLR_TX_OVER); if (val & IG4_INTR_TX_ABRT) { src = reg_read(sc, IG4_REG_TX_ABRT_SOURCE); reg_read(sc, IG4_REG_CLR_TX_ABORT); /* User-requested abort. Not really a error */ if (src & IG4_ABRTSRC_TRANSFER) return (IIC_ESTATUS); /* Master has lost arbitration */ if (src & IG4_ABRTSRC_ARBLOST) return (IIC_EBUSBSY); /* Did not receive an acknowledge from the remote slave */ if (src & (IG4_ABRTSRC_TXNOACK_ADDR7 | IG4_ABRTSRC_TXNOACK_ADDR10_1 | IG4_ABRTSRC_TXNOACK_ADDR10_2 | IG4_ABRTSRC_TXNOACK_DATA | IG4_ABRTSRC_GENCALL_NOACK)) return (IIC_ENOACK); /* Programming errors */ if (src & (IG4_ABRTSRC_GENCALL_READ | IG4_ABRTSRC_NORESTART_START | IG4_ABRTSRC_NORESTART_10)) return (IIC_ENOTSUPP); /* Other errors */ if (src & IG4_ABRTSRC_ACKED_START) return (IIC_EBUSERR); } /* * TX_OVER, RX_OVER and RX_UNDER are caused by wrong RX/TX FIFO depth * detection or driver's read/write pipelining errors. */ if (val & (IG4_INTR_TX_OVER | IG4_INTR_RX_OVER)) return (IIC_EOVERFLOW); if (val & IG4_INTR_RX_UNDER) return (IIC_EUNDERFLOW); return (IIC_NOERR); } /* * Enable or disable the controller and wait for the controller to acknowledge * the state change. */ static int set_controller(ig4iic_softc_t *sc, uint32_t ctl) { int retry; int error; uint32_t v; /* * When the controller is enabled, interrupt on STOP detect * or receive character ready and clear pending interrupts. */ ig4iic_set_intr_mask(sc, 0); if (ctl & IG4_I2C_ENABLE) reg_read(sc, IG4_REG_CLR_INTR); reg_write(sc, IG4_REG_I2C_EN, ctl); error = IIC_ETIMEOUT; for (retry = 100; retry > 0; --retry) { v = reg_read(sc, IG4_REG_ENABLE_STATUS); if (((v ^ ctl) & IG4_I2C_ENABLE) == 0) { error = 0; break; } pause("i2cslv", 1); } return (error); } /* * Wait up to 25ms for the requested interrupt using a 25uS polling loop. */ static int wait_intr(ig4iic_softc_t *sc, uint32_t intr) { uint32_t v; int error; int txlvl = -1; u_int count_us = 0; u_int limit_us = 1000000; /* 1sec */ for (;;) { /* * Check requested status */ v = reg_read(sc, IG4_REG_RAW_INTR_STAT); error = intrstat2iic(sc, v & IG4_INTR_ERR_MASK); if (error || (v & intr)) break; /* * When waiting for the transmit FIFO to become empty, * reset the timeout if we see a change in the transmit * FIFO level as progress is being made. */ if (intr & (IG4_INTR_TX_EMPTY | IG4_INTR_STOP_DET)) { v = reg_read(sc, IG4_REG_TXFLR) & IG4_FIFOLVL_MASK; if (txlvl != v) { txlvl = v; count_us = 0; } } /* * Stop if we've run out of time. */ if (count_us >= limit_us) { error = IIC_ETIMEOUT; break; } /* * When polling is not requested let the interrupt do its work. */ if (!DO_POLL(sc)) { mtx_lock_spin(&sc->io_lock); ig4iic_set_intr_mask(sc, intr | IG4_INTR_ERR_MASK); msleep_spin(sc, &sc->io_lock, "i2cwait", (hz + 99) / 100); /* sleep up to 10ms */ ig4iic_set_intr_mask(sc, 0); mtx_unlock_spin(&sc->io_lock); count_us += 10000; } else { DELAY(25); count_us += 25; } } return (error); } /* * Set the slave address. The controller must be disabled when * changing the address. * * This operation does not issue anything to the I2C bus but sets * the target address for when the controller later issues a START. */ static void set_slave_addr(ig4iic_softc_t *sc, uint8_t slave) { uint32_t tar; uint32_t ctl; bool use_10bit; use_10bit = false; if (sc->slave_valid && sc->last_slave == slave && sc->use_10bit == use_10bit) { return; } sc->use_10bit = use_10bit; /* * Wait for TXFIFO to drain before disabling the controller. */ wait_intr(sc, IG4_INTR_TX_EMPTY); set_controller(sc, 0); ctl = reg_read(sc, IG4_REG_CTL); ctl &= ~IG4_CTL_10BIT; ctl |= IG4_CTL_RESTARTEN; tar = slave; if (sc->use_10bit) { tar |= IG4_TAR_10BIT; ctl |= IG4_CTL_10BIT; } reg_write(sc, IG4_REG_CTL, ctl); reg_write(sc, IG4_REG_TAR_ADD, tar); set_controller(sc, IG4_I2C_ENABLE); sc->slave_valid = true; sc->last_slave = slave; } /* * IICBUS API FUNCTIONS */ static int ig4iic_xfer_start(ig4iic_softc_t *sc, uint16_t slave, bool repeated_start) { set_slave_addr(sc, slave >> 1); if (!repeated_start) { /* * Clear any previous TX/RX FIFOs overflow/underflow bits * and I2C bus STOP condition. */ reg_read(sc, IG4_REG_CLR_INTR); } return (0); } static bool ig4iic_xfer_is_started(ig4iic_softc_t *sc) { /* * It requires that no IG4_REG_CLR_INTR or IG4_REG_CLR_START/STOP_DET * register reads is issued after START condition. */ return ((reg_read(sc, IG4_REG_RAW_INTR_STAT) & (IG4_INTR_START_DET | IG4_INTR_STOP_DET)) == IG4_INTR_START_DET); } static int ig4iic_xfer_abort(ig4iic_softc_t *sc) { int error; /* Request send of STOP condition and flush of TX FIFO */ set_controller(sc, IG4_I2C_ABORT | IG4_I2C_ENABLE); /* * Wait for the TX_ABRT interrupt with ABRTSRC_TRANSFER * bit set in TX_ABRT_SOURCE register. */ error = wait_intr(sc, IG4_INTR_STOP_DET); set_controller(sc, IG4_I2C_ENABLE); return (error == IIC_ESTATUS ? 0 : error); } /* * Amount of unread data before next burst to get better I2C bus utilization. * 2 bytes is enough in FAST mode. 8 bytes is better in FAST+ and HIGH modes. * Intel-recommended value is 16 for DMA transfers with 64-byte depth FIFOs. */ #define IG4_FIFO_LOWAT 2 static int ig4iic_read(ig4iic_softc_t *sc, uint8_t *buf, uint16_t len, bool repeated_start, bool stop) { uint32_t cmd; int requested = 0; int received = 0; int burst, target, lowat = 0; int error; if (len == 0) return (0); while (received < len) { burst = sc->cfg.txfifo_depth - (reg_read(sc, IG4_REG_TXFLR) & IG4_FIFOLVL_MASK); if (burst <= 0) { error = wait_intr(sc, IG4_INTR_TX_EMPTY); if (error) break; burst = sc->cfg.txfifo_depth; } /* Ensure we have enough free space in RXFIFO */ burst = MIN(burst, sc->cfg.rxfifo_depth - lowat); target = MIN(requested + burst, (int)len); while (requested < target) { cmd = IG4_DATA_COMMAND_RD; if (repeated_start && requested == 0) cmd |= IG4_DATA_RESTART; if (stop && requested == len - 1) cmd |= IG4_DATA_STOP; reg_write(sc, IG4_REG_DATA_CMD, cmd); requested++; } /* Leave some data queued to maintain the hardware pipeline */ lowat = 0; if (requested != len && requested - received > IG4_FIFO_LOWAT) lowat = IG4_FIFO_LOWAT; /* After TXFLR fills up, clear it by reading available data */ while (received < requested - lowat) { burst = MIN((int)len - received, reg_read(sc, IG4_REG_RXFLR) & IG4_FIFOLVL_MASK); if (burst > 0) { while (burst--) buf[received++] = 0xFF & reg_read(sc, IG4_REG_DATA_CMD); } else { error = wait_intr(sc, IG4_INTR_RX_FULL); if (error) goto out; } } } out: return (error); } static int ig4iic_write(ig4iic_softc_t *sc, uint8_t *buf, uint16_t len, bool repeated_start, bool stop) { uint32_t cmd; int sent = 0; int burst, target; int error; bool lowat_set = false; if (len == 0) return (0); while (sent < len) { burst = sc->cfg.txfifo_depth - (reg_read(sc, IG4_REG_TXFLR) & IG4_FIFOLVL_MASK); target = MIN(sent + burst, (int)len); /* Leave some data queued to maintain the hardware pipeline */ if (!lowat_set && target != len) { lowat_set = true; reg_write(sc, IG4_REG_TX_TL, IG4_FIFO_LOWAT); } while(sent < target) { cmd = buf[sent]; if (repeated_start && sent == 0) cmd |= IG4_DATA_RESTART; if (stop && sent == len - 1) cmd |= IG4_DATA_STOP; reg_write(sc, IG4_REG_DATA_CMD, cmd); sent++; } if (sent < len) { error = wait_intr(sc, IG4_INTR_TX_EMPTY); if (error) break; } } if (lowat_set) reg_write(sc, IG4_REG_TX_TL, 0); return (error); } int ig4iic_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs) { ig4iic_softc_t *sc = device_get_softc(dev); const char *reason = NULL; uint32_t i; int error; int unit; bool rpstart; bool stop; bool allocated; /* * The hardware interface imposes limits on allowed I2C messages. * It is not possible to explicitly send a start or stop. * They are automatically sent (or not sent, depending on the * configuration) when a data byte is transferred. * For this reason it's impossible to send a message with no data * at all (like an SMBus quick message). * The start condition is automatically generated after the stop * condition, so it's impossible to not have a start after a stop. * The repeated start condition is automatically sent if a change * of the transfer direction happens, so it's impossible to have * a change of direction without a (repeated) start. * The repeated start can be forced even without the change of * direction. * Changing the target slave address requires resetting the hardware * state, so it's impossible to do that without the stop followed * by the start. */ for (i = 0; i < nmsgs; i++) { #if 0 if (i == 0 && (msgs[i].flags & IIC_M_NOSTART) != 0) { reason = "first message without start"; break; } if (i == nmsgs - 1 && (msgs[i].flags & IIC_M_NOSTOP) != 0) { reason = "last message without stop"; break; } #endif if (msgs[i].len == 0) { reason = "message with no data"; break; } if (i > 0) { if ((msgs[i].flags & IIC_M_NOSTART) != 0 && (msgs[i - 1].flags & IIC_M_NOSTOP) == 0) { reason = "stop not followed by start"; break; } if ((msgs[i - 1].flags & IIC_M_NOSTOP) != 0 && msgs[i].slave != msgs[i - 1].slave) { reason = "change of slave without stop"; break; } if ((msgs[i].flags & IIC_M_NOSTART) != 0 && (msgs[i].flags & IIC_M_RD) != (msgs[i - 1].flags & IIC_M_RD)) { reason = "change of direction without repeated" " start"; break; } } } if (reason != NULL) { if (bootverbose) device_printf(dev, "%s\n", reason); return (IIC_ENOTSUPP); } /* Check if device is already allocated with iicbus_request_bus() */ allocated = sx_xlocked(&sc->call_lock) != 0; if (!allocated) sx_xlock(&sc->call_lock); /* Debugging - dump registers. */ if (ig4_dump) { unit = device_get_unit(dev); if (ig4_dump & (1 << unit)) { ig4_dump &= ~(1 << unit); ig4iic_dump(sc); } } /* * Clear any previous abort condition that may have been holding * the txfifo in reset. */ reg_read(sc, IG4_REG_CLR_TX_ABORT); rpstart = false; error = 0; for (i = 0; i < nmsgs; i++) { if ((msgs[i].flags & IIC_M_NOSTART) == 0) { error = ig4iic_xfer_start(sc, msgs[i].slave, rpstart); } else { if (!sc->slave_valid || (msgs[i].slave >> 1) != sc->last_slave) { device_printf(dev, "start condition suppressed" "but slave address is not set up"); error = EINVAL; break; } rpstart = false; } if (error != 0) break; stop = (msgs[i].flags & IIC_M_NOSTOP) == 0; if (msgs[i].flags & IIC_M_RD) error = ig4iic_read(sc, msgs[i].buf, msgs[i].len, rpstart, stop); else error = ig4iic_write(sc, msgs[i].buf, msgs[i].len, rpstart, stop); /* Wait for error or stop condition occurred on the I2C bus */ if (stop && error == 0) { error = wait_intr(sc, IG4_INTR_STOP_DET); if (error == 0) reg_read(sc, IG4_REG_CLR_INTR); } if (error != 0) { /* * Send STOP condition if it's not done yet and flush * both FIFOs. Do a controller soft reset if transfer * abort is failed. */ if (ig4iic_xfer_is_started(sc) && ig4iic_xfer_abort(sc) != 0) { device_printf(sc->dev, "Failed to abort " "transfer. Do the controller reset.\n"); ig4iic_set_config(sc, true); } else { while (reg_read(sc, IG4_REG_I2C_STA) & IG4_STATUS_RX_NOTEMPTY) reg_read(sc, IG4_REG_DATA_CMD); reg_read(sc, IG4_REG_TX_ABRT_SOURCE); reg_read(sc, IG4_REG_CLR_INTR); } break; } rpstart = !stop; } if (!allocated) sx_unlock(&sc->call_lock); return (error); } int ig4iic_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr) { ig4iic_softc_t *sc = device_get_softc(dev); bool allocated; allocated = sx_xlocked(&sc->call_lock) != 0; if (!allocated) sx_xlock(&sc->call_lock); /* TODO handle speed configuration? */ if (oldaddr != NULL) *oldaddr = sc->last_slave << 1; set_slave_addr(sc, addr >> 1); if (addr == IIC_UNKNOWN) sc->slave_valid = false; if (!allocated) sx_unlock(&sc->call_lock); return (0); } int ig4iic_callback(device_t dev, int index, caddr_t data) { ig4iic_softc_t *sc = device_get_softc(dev); int error = 0; int how; switch (index) { case IIC_REQUEST_BUS: /* force polling if ig4iic is requested with IIC_DONTWAIT */ how = *(int *)data; if ((how & IIC_WAIT) == 0) { if (sx_try_xlock(&sc->call_lock) == 0) error = IIC_EBUSBSY; else sc->poll = true; } else sx_xlock(&sc->call_lock); break; case IIC_RELEASE_BUS: sc->poll = false; sx_unlock(&sc->call_lock); break; default: error = errno2iic(EINVAL); } return (error); } /* * Clock register values can be calculated with following rough equations: * SCL_HCNT = ceil(IC clock rate * tHIGH) * SCL_LCNT = ceil(IC clock rate * tLOW) * SDA_HOLD = ceil(IC clock rate * SDA hold time) * Precise equations take signal's falling, rising and spike suppression * times in to account. They can be found in Synopsys or Intel documentation. * * Here we snarf formulas and defaults from Linux driver to be able to use * timing values provided by Intel LPSS driver "as is". */ static int ig4iic_clk_params(const struct ig4_hw *hw, int speed, uint16_t *scl_hcnt, uint16_t *scl_lcnt, uint16_t *sda_hold) { uint32_t thigh, tlow, tf_max; /* nsec */ uint32_t sda_fall_time; /* nsec */ uint32_t scl_fall_time; /* nsec */ switch (speed) { case IG4_CTL_SPEED_STD: thigh = IG4_SPEED_STD_THIGH; tlow = IG4_SPEED_STD_TLOW; tf_max = IG4_SPEED_STD_TF_MAX; break; case IG4_CTL_SPEED_FAST: thigh = IG4_SPEED_FAST_THIGH; tlow = IG4_SPEED_FAST_TLOW; tf_max = IG4_SPEED_FAST_TF_MAX; break; default: return (EINVAL); } /* Use slowest falling time defaults to be on the safe side */ sda_fall_time = hw->sda_fall_time == 0 ? tf_max : hw->sda_fall_time; *scl_hcnt = (uint16_t) ((hw->ic_clock_rate * (thigh + sda_fall_time) + 500) / 1000 - 3); scl_fall_time = hw->scl_fall_time == 0 ? tf_max : hw->scl_fall_time; *scl_lcnt = (uint16_t) ((hw->ic_clock_rate * (tlow + scl_fall_time) + 500) / 1000 - 1); /* * There is no "known good" default value for tHD;DAT so keep SDA_HOLD * intact if sda_hold_time value is not provided. */ if (hw->sda_hold_time != 0) *sda_hold = (uint16_t) ((hw->ic_clock_rate * hw->sda_hold_time + 500) / 1000); return (0); } #ifdef DEV_ACPI static ACPI_STATUS ig4iic_acpi_params(ACPI_HANDLE handle, char *method, uint16_t *scl_hcnt, uint16_t *scl_lcnt, uint16_t *sda_hold) { ACPI_BUFFER buf; ACPI_OBJECT *obj, *elems; ACPI_STATUS status; buf.Pointer = NULL; buf.Length = ACPI_ALLOCATE_BUFFER; status = AcpiEvaluateObject(handle, method, NULL, &buf); if (ACPI_FAILURE(status)) return (status); status = AE_TYPE; obj = (ACPI_OBJECT *)buf.Pointer; if (obj->Type == ACPI_TYPE_PACKAGE && obj->Package.Count == 3) { elems = obj->Package.Elements; *scl_hcnt = elems[0].Integer.Value & IG4_SCL_CLOCK_MASK; *scl_lcnt = elems[1].Integer.Value & IG4_SCL_CLOCK_MASK; *sda_hold = elems[2].Integer.Value & IG4_SDA_TX_HOLD_MASK; status = AE_OK; } AcpiOsFree(obj); return (status); } #endif /* DEV_ACPI */ static void ig4iic_get_config(ig4iic_softc_t *sc) { const struct ig4_hw *hw; uint32_t v; #ifdef DEV_ACPI ACPI_HANDLE handle; #endif /* Fetch default hardware config from controller */ sc->cfg.version = reg_read(sc, IG4_REG_COMP_VER); sc->cfg.bus_speed = reg_read(sc, IG4_REG_CTL) & IG4_CTL_SPEED_MASK; sc->cfg.ss_scl_hcnt = reg_read(sc, IG4_REG_SS_SCL_HCNT) & IG4_SCL_CLOCK_MASK; sc->cfg.ss_scl_lcnt = reg_read(sc, IG4_REG_SS_SCL_LCNT) & IG4_SCL_CLOCK_MASK; sc->cfg.fs_scl_hcnt = reg_read(sc, IG4_REG_FS_SCL_HCNT) & IG4_SCL_CLOCK_MASK; sc->cfg.fs_scl_lcnt = reg_read(sc, IG4_REG_FS_SCL_LCNT) & IG4_SCL_CLOCK_MASK; sc->cfg.ss_sda_hold = sc->cfg.fs_sda_hold = reg_read(sc, IG4_REG_SDA_HOLD) & IG4_SDA_TX_HOLD_MASK; if (sc->cfg.bus_speed != IG4_CTL_SPEED_STD) sc->cfg.bus_speed = IG4_CTL_SPEED_FAST; /* REG_COMP_PARAM1 is not documented in latest Intel specs */ if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) { v = reg_read(sc, IG4_REG_COMP_PARAM1); if (IG4_PARAM1_TXFIFO_DEPTH(v) != 0) sc->cfg.txfifo_depth = IG4_PARAM1_TXFIFO_DEPTH(v); if (IG4_PARAM1_RXFIFO_DEPTH(v) != 0) sc->cfg.rxfifo_depth = IG4_PARAM1_RXFIFO_DEPTH(v); } else { /* * Hardware does not allow FIFO Threshold Levels value to be * set larger than the depth of the buffer. If an attempt is * made to do that, the actual value set will be the maximum * depth of the buffer. */ v = reg_read(sc, IG4_REG_TX_TL); reg_write(sc, IG4_REG_TX_TL, v | IG4_FIFO_MASK); sc->cfg.txfifo_depth = (reg_read(sc, IG4_REG_TX_TL) & IG4_FIFO_MASK) + 1; reg_write(sc, IG4_REG_TX_TL, v); v = reg_read(sc, IG4_REG_RX_TL); reg_write(sc, IG4_REG_RX_TL, v | IG4_FIFO_MASK); sc->cfg.rxfifo_depth = (reg_read(sc, IG4_REG_RX_TL) & IG4_FIFO_MASK) + 1; reg_write(sc, IG4_REG_RX_TL, v); } /* Override hardware config with IC_clock-based counter values */ if (ig4_timings < 2 && sc->version < nitems(ig4iic_hw)) { hw = &ig4iic_hw[sc->version]; sc->cfg.bus_speed = IG4_CTL_SPEED_FAST; ig4iic_clk_params(hw, IG4_CTL_SPEED_STD, &sc->cfg.ss_scl_hcnt, &sc->cfg.ss_scl_lcnt, &sc->cfg.ss_sda_hold); ig4iic_clk_params(hw, IG4_CTL_SPEED_FAST, &sc->cfg.fs_scl_hcnt, &sc->cfg.fs_scl_lcnt, &sc->cfg.fs_sda_hold); if (hw->txfifo_depth != 0) sc->cfg.txfifo_depth = hw->txfifo_depth; if (hw->rxfifo_depth != 0) sc->cfg.rxfifo_depth = hw->rxfifo_depth; } else if (ig4_timings == 2) { /* * Timings of original ig4 driver: * Program based on a 25000 Hz clock. This is a bit of a * hack (obviously). The defaults are 400 and 470 for standard * and 60 and 130 for fast. The defaults for standard fail * utterly (presumably cause an abort) because the clock time * is ~18.8ms by default. This brings it down to ~4ms. */ sc->cfg.bus_speed = IG4_CTL_SPEED_STD; sc->cfg.ss_scl_hcnt = sc->cfg.fs_scl_hcnt = 100; sc->cfg.ss_scl_lcnt = sc->cfg.fs_scl_lcnt = 125; if (sc->version == IG4_SKYLAKE) sc->cfg.ss_sda_hold = sc->cfg.fs_sda_hold = 28; } #ifdef DEV_ACPI /* Evaluate SSCN and FMCN ACPI methods to fetch timings */ if (ig4_timings == 0 && (handle = acpi_get_handle(sc->dev)) != NULL) { ig4iic_acpi_params(handle, "SSCN", &sc->cfg.ss_scl_hcnt, &sc->cfg.ss_scl_lcnt, &sc->cfg.ss_sda_hold); ig4iic_acpi_params(handle, "FMCN", &sc->cfg.fs_scl_hcnt, &sc->cfg.fs_scl_lcnt, &sc->cfg.fs_sda_hold); } #endif if (bootverbose) { device_printf(sc->dev, "Controller parameters:\n"); printf(" Speed: %s\n", sc->cfg.bus_speed == IG4_CTL_SPEED_STD ? "Std" : "Fast"); printf(" Regs: HCNT :LCNT :SDAHLD\n"); printf(" Std: 0x%04hx:0x%04hx:0x%04hx\n", sc->cfg.ss_scl_hcnt, sc->cfg.ss_scl_lcnt, sc->cfg.ss_sda_hold); printf(" Fast: 0x%04hx:0x%04hx:0x%04hx\n", sc->cfg.fs_scl_hcnt, sc->cfg.fs_scl_lcnt, sc->cfg.fs_sda_hold); printf(" FIFO: RX:0x%04x: TX:0x%04x\n", sc->cfg.rxfifo_depth, sc->cfg.txfifo_depth); } } static int ig4iic_set_config(ig4iic_softc_t *sc, bool reset) { uint32_t v; v = reg_read(sc, IG4_REG_DEVIDLE_CTRL); if (IG4_HAS_ADDREGS(sc->version) && (v & IG4_RESTORE_REQUIRED)) { reg_write(sc, IG4_REG_DEVIDLE_CTRL, IG4_DEVICE_IDLE | IG4_RESTORE_REQUIRED); reg_write(sc, IG4_REG_DEVIDLE_CTRL, 0); pause("i2crst", 1); reset = true; } if ((sc->version == IG4_HASWELL || sc->version == IG4_ATOM) && reset) { reg_write(sc, IG4_REG_RESETS_HSW, IG4_RESETS_ASSERT_HSW); reg_write(sc, IG4_REG_RESETS_HSW, IG4_RESETS_DEASSERT_HSW); } else if (IG4_HAS_ADDREGS(sc->version) && reset) { reg_write(sc, IG4_REG_RESETS_SKL, IG4_RESETS_ASSERT_SKL); reg_write(sc, IG4_REG_RESETS_SKL, IG4_RESETS_DEASSERT_SKL); } if (sc->version == IG4_ATOM) v = reg_read(sc, IG4_REG_COMP_TYPE); if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) { v = reg_read(sc, IG4_REG_COMP_PARAM1); v = reg_read(sc, IG4_REG_GENERAL); /* * The content of IG4_REG_GENERAL is different for each * controller version. */ if (sc->version == IG4_HASWELL && (v & IG4_GENERAL_SWMODE) == 0) { v |= IG4_GENERAL_SWMODE; reg_write(sc, IG4_REG_GENERAL, v); v = reg_read(sc, IG4_REG_GENERAL); } } if (sc->version == IG4_HASWELL) { v = reg_read(sc, IG4_REG_SW_LTR_VALUE); v = reg_read(sc, IG4_REG_AUTO_LTR_VALUE); } else if (IG4_HAS_ADDREGS(sc->version)) { v = reg_read(sc, IG4_REG_ACTIVE_LTR_VALUE); v = reg_read(sc, IG4_REG_IDLE_LTR_VALUE); } if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) { v = reg_read(sc, IG4_REG_COMP_VER); if (v < IG4_COMP_MIN_VER) return(ENXIO); } if (set_controller(sc, 0)) { device_printf(sc->dev, "controller error during attach-1\n"); return (ENXIO); } reg_read(sc, IG4_REG_CLR_INTR); reg_write(sc, IG4_REG_INTR_MASK, 0); sc->intr_mask = 0; reg_write(sc, IG4_REG_SS_SCL_HCNT, sc->cfg.ss_scl_hcnt); reg_write(sc, IG4_REG_SS_SCL_LCNT, sc->cfg.ss_scl_lcnt); reg_write(sc, IG4_REG_FS_SCL_HCNT, sc->cfg.fs_scl_hcnt); reg_write(sc, IG4_REG_FS_SCL_LCNT, sc->cfg.fs_scl_lcnt); reg_write(sc, IG4_REG_SDA_HOLD, (sc->cfg.bus_speed & IG4_CTL_SPEED_MASK) == IG4_CTL_SPEED_STD ? sc->cfg.ss_sda_hold : sc->cfg.fs_sda_hold); /* * Use a threshold of 1 so we get interrupted on each character, * allowing us to use mtx_sleep() in our poll code. Not perfect * but this is better than using DELAY() for receiving data. * * See ig4_var.h for details on interrupt handler synchronization. */ reg_write(sc, IG4_REG_RX_TL, 0); reg_write(sc, IG4_REG_TX_TL, 0); reg_write(sc, IG4_REG_CTL, IG4_CTL_MASTER | IG4_CTL_SLAVE_DISABLE | IG4_CTL_RESTARTEN | (sc->cfg.bus_speed & IG4_CTL_SPEED_MASK)); /* Force setting of the target address on the next transfer */ sc->slave_valid = false; return (0); } /* * Called from ig4iic_pci_attach/detach() */ int ig4iic_attach(ig4iic_softc_t *sc) { int error; mtx_init(&sc->io_lock, "IG4 I/O lock", NULL, MTX_SPIN); sx_init(&sc->call_lock, "IG4 call lock"); ig4iic_get_config(sc); error = ig4iic_set_config(sc, IG4_HAS_ADDREGS(sc->version)); if (error) goto done; sc->iicbus = device_add_child(sc->dev, "iicbus", -1); if (sc->iicbus == NULL) { device_printf(sc->dev, "iicbus driver not found\n"); error = ENXIO; goto done; } if (set_controller(sc, IG4_I2C_ENABLE)) { device_printf(sc->dev, "controller error during attach-2\n"); error = ENXIO; goto done; } if (set_controller(sc, 0)) { device_printf(sc->dev, "controller error during attach-3\n"); error = ENXIO; goto done; } error = bus_setup_intr(sc->dev, sc->intr_res, INTR_TYPE_MISC | INTR_MPSAFE, ig4iic_intr, NULL, sc, &sc->intr_handle); if (error) { device_printf(sc->dev, "Unable to setup irq: error %d\n", error); } error = bus_generic_attach(sc->dev); if (error) { device_printf(sc->dev, "failed to attach child: error %d\n", error); } done: return (error); } int ig4iic_detach(ig4iic_softc_t *sc) { int error; if (device_is_attached(sc->dev)) { error = bus_generic_detach(sc->dev); if (error) return (error); } if (sc->iicbus) device_delete_child(sc->dev, sc->iicbus); if (sc->intr_handle) bus_teardown_intr(sc->dev, sc->intr_res, sc->intr_handle); sx_xlock(&sc->call_lock); sc->iicbus = NULL; sc->intr_handle = NULL; reg_write(sc, IG4_REG_INTR_MASK, 0); set_controller(sc, 0); sx_xunlock(&sc->call_lock); mtx_destroy(&sc->io_lock); sx_destroy(&sc->call_lock); return (0); } int ig4iic_suspend(ig4iic_softc_t *sc) { int error; /* suspend all children */ error = bus_generic_suspend(sc->dev); sx_xlock(&sc->call_lock); set_controller(sc, 0); if (IG4_HAS_ADDREGS(sc->version)) { /* * Place the device in the idle state, just to be safe */ reg_write(sc, IG4_REG_DEVIDLE_CTRL, IG4_DEVICE_IDLE); /* * Controller can become dysfunctional if I2C lines are pulled * down when suspend procedure turns off power to I2C device. * Place device in the reset state to avoid this. */ reg_write(sc, IG4_REG_RESETS_SKL, IG4_RESETS_ASSERT_SKL); } sx_xunlock(&sc->call_lock); return (error); } int ig4iic_resume(ig4iic_softc_t *sc) { int error; sx_xlock(&sc->call_lock); if (ig4iic_set_config(sc, IG4_HAS_ADDREGS(sc->version))) device_printf(sc->dev, "controller error during resume\n"); sx_xunlock(&sc->call_lock); error = bus_generic_resume(sc->dev); return (error); } /* * Interrupt Operation, see ig4_var.h for locking semantics. */ static int ig4iic_intr(void *cookie) { ig4iic_softc_t *sc = cookie; int retval = FILTER_STRAY; mtx_lock_spin(&sc->io_lock); /* Ignore stray interrupts */ if (sc->intr_mask != 0 && reg_read(sc, IG4_REG_INTR_STAT) != 0) { /* Interrupt bits are cleared in wait_intr() loop */ ig4iic_set_intr_mask(sc, 0); wakeup(sc); retval = FILTER_HANDLED; } mtx_unlock_spin(&sc->io_lock); return (retval); } #define REGDUMP(sc, reg) \ device_printf(sc->dev, " %-23s %08x\n", #reg, reg_read(sc, reg)) static void ig4iic_dump(ig4iic_softc_t *sc) { device_printf(sc->dev, "ig4iic register dump:\n"); REGDUMP(sc, IG4_REG_CTL); REGDUMP(sc, IG4_REG_TAR_ADD); REGDUMP(sc, IG4_REG_SS_SCL_HCNT); REGDUMP(sc, IG4_REG_SS_SCL_LCNT); REGDUMP(sc, IG4_REG_FS_SCL_HCNT); REGDUMP(sc, IG4_REG_FS_SCL_LCNT); REGDUMP(sc, IG4_REG_INTR_STAT); REGDUMP(sc, IG4_REG_INTR_MASK); REGDUMP(sc, IG4_REG_RAW_INTR_STAT); REGDUMP(sc, IG4_REG_RX_TL); REGDUMP(sc, IG4_REG_TX_TL); REGDUMP(sc, IG4_REG_I2C_EN); REGDUMP(sc, IG4_REG_I2C_STA); REGDUMP(sc, IG4_REG_TXFLR); REGDUMP(sc, IG4_REG_RXFLR); REGDUMP(sc, IG4_REG_SDA_HOLD); REGDUMP(sc, IG4_REG_TX_ABRT_SOURCE); REGDUMP(sc, IG4_REG_SLV_DATA_NACK); REGDUMP(sc, IG4_REG_DMA_CTRL); REGDUMP(sc, IG4_REG_DMA_TDLR); REGDUMP(sc, IG4_REG_DMA_RDLR); REGDUMP(sc, IG4_REG_SDA_SETUP); REGDUMP(sc, IG4_REG_ENABLE_STATUS); REGDUMP(sc, IG4_REG_COMP_PARAM1); REGDUMP(sc, IG4_REG_COMP_VER); if (sc->version == IG4_ATOM) { REGDUMP(sc, IG4_REG_COMP_TYPE); REGDUMP(sc, IG4_REG_CLK_PARMS); } if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) { REGDUMP(sc, IG4_REG_RESETS_HSW); REGDUMP(sc, IG4_REG_GENERAL); } else if (sc->version == IG4_SKYLAKE) { REGDUMP(sc, IG4_REG_RESETS_SKL); } if (sc->version == IG4_HASWELL) { REGDUMP(sc, IG4_REG_SW_LTR_VALUE); REGDUMP(sc, IG4_REG_AUTO_LTR_VALUE); } else if (IG4_HAS_ADDREGS(sc->version)) { REGDUMP(sc, IG4_REG_ACTIVE_LTR_VALUE); REGDUMP(sc, IG4_REG_IDLE_LTR_VALUE); } } #undef REGDUMP DRIVER_MODULE(iicbus, ig4iic, iicbus_driver, NULL, NULL); #ifdef DEV_ACPI DRIVER_MODULE(acpi_iicbus, ig4iic, acpi_iicbus_driver, NULL, NULL); #endif MODULE_DEPEND(ig4iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); MODULE_VERSION(ig4iic, 1);