diff options
author | Chris Ching <chingcodes@chromium.org> | 2017-12-06 14:26:15 -0700 |
---|---|---|
committer | Chris Ching <chingcodes@chromium.org> | 2017-12-22 16:39:42 +0000 |
commit | b8dc63bdfe04fc15553f1ea6e42583cbdaad38ac (patch) | |
tree | 6c25cdb3bb62df3cb80b01f111467b98800d18d0 /src/soc/intel/common/block/i2c/lpss_i2c.c | |
parent | 17e85adc91d905919f8c4a512125ebd457ce99db (diff) |
ic2/designware: Move Intel i2c logic to shared driver
BUG=b:70232394
BRANCH=none
TEST=emerge-reef coreboot
emerge-glados
Change-Id: Idb453a4d2411163e6b4a8422310bf272eac5d379
Signed-off-by: Chris Ching <chingcodes@chromium.org>
Reviewed-on: https://review.coreboot.org/22822
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src/soc/intel/common/block/i2c/lpss_i2c.c')
-rw-r--r-- | src/soc/intel/common/block/i2c/lpss_i2c.c | 673 |
1 files changed, 0 insertions, 673 deletions
diff --git a/src/soc/intel/common/block/i2c/lpss_i2c.c b/src/soc/intel/common/block/i2c/lpss_i2c.c deleted file mode 100644 index 9ae7831524..0000000000 --- a/src/soc/intel/common/block/i2c/lpss_i2c.c +++ /dev/null @@ -1,673 +0,0 @@ -/* - * This file is part of the coreboot project. - * - * Copyright 2009 Vipin Kumar, ST Microelectronics - * Copyright 2016 Google Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; version 2 of the License. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ - -#include <arch/acpigen.h> -#include <arch/io.h> -#include <console/console.h> -#include <device/device.h> -#include <device/i2c_simple.h> -#include <device/pci.h> -#include <device/pci_def.h> -#include <device/pci_ids.h> -#include <intelblocks/lpss_i2c.h> -#include <string.h> -#include <timer.h> -#include "lpss_i2c.h" - -/* Use a ~10ms timeout for various operations */ -#define LPSS_I2C_TIMEOUT_US 10000 - -/* High and low times in different speed modes (in ns) */ -enum { - /* SDA Hold Time */ - DEFAULT_SDA_HOLD_TIME = 300, - /* Standard Speed */ - MIN_SS_SCL_HIGHTIME = 4000, - MIN_SS_SCL_LOWTIME = 4700, - /* Fast Speed */ - MIN_FS_SCL_HIGHTIME = 600, - MIN_FS_SCL_LOWTIME = 1300, - /* Fast Plus Speed */ - MIN_FP_SCL_HIGHTIME = 260, - MIN_FP_SCL_LOWTIME = 500, - /* High Speed */ - MIN_HS_SCL_HIGHTIME = 60, - MIN_HS_SCL_LOWTIME = 160, -}; - -/* Frequency represented as ticks per ns. Can also be used to calculate - * the number of ticks to meet a time target or the period. */ -struct freq { - uint32_t ticks; - uint32_t ns; -}; - -/* Control register definitions */ -enum { - CONTROL_MASTER_MODE = (1 << 0), - CONTROL_SPEED_SS = (1 << 1), - CONTROL_SPEED_FS = (1 << 2), - CONTROL_SPEED_HS = (3 << 1), - CONTROL_SPEED_MASK = (3 << 1), - CONTROL_10BIT_SLAVE = (1 << 3), - CONTROL_10BIT_MASTER = (1 << 4), - CONTROL_RESTART_ENABLE = (1 << 5), - CONTROL_SLAVE_DISABLE = (1 << 6), -}; - -/* Command/Data register definitions */ -enum { - CMD_DATA_CMD = (1 << 8), - CMD_DATA_STOP = (1 << 9), -}; - -/* Status register definitions */ -enum { - STATUS_ACTIVITY = (1 << 0), - STATUS_TX_FIFO_NOT_FULL = (1 << 1), - STATUS_TX_FIFO_EMPTY = (1 << 2), - STATUS_RX_FIFO_NOT_EMPTY = (1 << 3), - STATUS_RX_FIFO_FULL = (1 << 4), - STATUS_MASTER_ACTIVITY = (1 << 5), - STATUS_SLAVE_ACTIVITY = (1 << 6), -}; - -/* Enable register definitions */ -enum { - ENABLE_CONTROLLER = (1 << 0), -}; - -/* Interrupt status register definitions */ -enum { - INTR_STAT_RX_UNDER = (1 << 0), - INTR_STAT_RX_OVER = (1 << 1), - INTR_STAT_RX_FULL = (1 << 2), - INTR_STAT_TX_OVER = (1 << 3), - INTR_STAT_TX_EMPTY = (1 << 4), - INTR_STAT_RD_REQ = (1 << 5), - INTR_STAT_TX_ABORT = (1 << 6), - INTR_STAT_RX_DONE = (1 << 7), - INTR_STAT_ACTIVITY = (1 << 8), - INTR_STAT_STOP_DET = (1 << 9), - INTR_STAT_START_DET = (1 << 10), - INTR_STAT_GEN_CALL = (1 << 11), -}; - -static const struct i2c_descriptor { - enum i2c_speed speed; - struct freq freq; - int min_thigh_ns; - int min_tlow_ns; -} speed_descriptors[] = { - { - .speed = I2C_SPEED_STANDARD, - .freq = { - .ticks = 100, - .ns = 1000*1000, - }, - .min_thigh_ns = MIN_SS_SCL_HIGHTIME, - .min_tlow_ns = MIN_SS_SCL_LOWTIME, - }, - { - .speed = I2C_SPEED_FAST, - .freq = { - .ticks = 400, - .ns = 1000*1000, - }, - .min_thigh_ns = MIN_FS_SCL_HIGHTIME, - .min_tlow_ns = MIN_FS_SCL_LOWTIME, - }, - { - .speed = I2C_SPEED_FAST_PLUS, - .freq = { - .ticks = 1, - .ns = 1000, - }, - .min_thigh_ns = MIN_FP_SCL_HIGHTIME, - .min_tlow_ns = MIN_FP_SCL_LOWTIME, - }, - { - /* 100pF max capacitance */ - .speed = I2C_SPEED_HIGH, - .freq = { - .ticks = 3400, - .ns = 1000*1000, - }, - .min_thigh_ns = MIN_HS_SCL_HIGHTIME, - .min_tlow_ns = MIN_HS_SCL_LOWTIME, - }, -}; - -static const struct soc_clock { - int clk_speed_mhz; - struct freq freq; -} soc_clocks[] = { - { - .clk_speed_mhz = 120, - .freq = { - .ticks = 120, - .ns = 1000, - }, - }, - { - .clk_speed_mhz = 133, - .freq = { - .ticks = 400, - .ns = 3000, - }, - }, -}; - -static const struct i2c_descriptor *get_bus_descriptor(enum i2c_speed speed) -{ - size_t i; - - for (i = 0; i < ARRAY_SIZE(speed_descriptors); i++) - if (speed == speed_descriptors[i].speed) - return &speed_descriptors[i]; - - return NULL; -} - -static const struct soc_clock *get_soc_descriptor(int ic_clk) -{ - size_t i; - - for (i = 0; i < ARRAY_SIZE(soc_clocks); i++) - if (ic_clk == soc_clocks[i].clk_speed_mhz) - return &soc_clocks[i]; - - return NULL; -} - -static int counts_from_time(const struct freq *f, int ns) -{ - return DIV_ROUND_UP(f->ticks * ns, f->ns); -} - -static int counts_from_freq(const struct freq *fast, const struct freq *slow) -{ - return DIV_ROUND_UP(fast->ticks * slow->ns, fast->ns * slow->ticks); -} - -/* Enable this I2C controller */ -static void lpss_i2c_enable(struct lpss_i2c_regs *regs) -{ - uint32_t enable = read32(®s->enable); - - if (!(enable & ENABLE_CONTROLLER)) - write32(®s->enable, enable | ENABLE_CONTROLLER); -} - -/* Disable this I2C controller */ -static int lpss_i2c_disable(struct lpss_i2c_regs *regs) -{ - uint32_t enable = read32(®s->enable); - - if (enable & ENABLE_CONTROLLER) { - struct stopwatch sw; - - write32(®s->enable, enable & ~ENABLE_CONTROLLER); - - /* Wait for enable bit to clear */ - stopwatch_init_usecs_expire(&sw, LPSS_I2C_TIMEOUT_US); - while (read32(®s->enable_status) & ENABLE_CONTROLLER) - if (stopwatch_expired(&sw)) - return -1; - } - - return 0; -} - -/* Wait for this I2C controller to go idle for transmit */ -static int lpss_i2c_wait_for_bus_idle(struct lpss_i2c_regs *regs) -{ - struct stopwatch sw; - - /* Start timeout for up to 16 bytes in FIFO */ - stopwatch_init_usecs_expire(&sw, 16 * LPSS_I2C_TIMEOUT_US); - - while (!stopwatch_expired(&sw)) { - uint32_t status = read32(®s->status); - - /* Check for master activity and keep waiting */ - if (status & STATUS_MASTER_ACTIVITY) - continue; - - /* Check for TX FIFO empty to indicate TX idle */ - if (status & STATUS_TX_FIFO_EMPTY) - return 0; - } - - /* Timed out while waiting for bus to go idle */ - return -1; -} - -/* Transfer one byte of one segment, sending stop bit if requested */ -static int lpss_i2c_transfer_byte(struct lpss_i2c_regs *regs, - const struct i2c_msg *segment, - size_t byte, int send_stop) -{ - struct stopwatch sw; - uint32_t cmd = CMD_DATA_CMD; /* Read op */ - - stopwatch_init_usecs_expire(&sw, LPSS_I2C_TIMEOUT_US); - - if (!(segment->flags & I2C_M_RD)) { - /* Write op only: Wait for FIFO not full */ - while (!(read32(®s->status) & STATUS_TX_FIFO_NOT_FULL)) { - if (stopwatch_expired(&sw)) { - printk(BIOS_ERR, "I2C transmit timeout\n"); - return -1; - } - } - cmd = segment->buf[byte]; - } - - /* Send stop on last byte, if desired */ - if (send_stop && byte == segment->len - 1) - cmd |= CMD_DATA_STOP; - - write32(®s->cmd_data, cmd); - - if (segment->flags & I2C_M_RD) { - /* Read op only: Wait for FIFO data and store it */ - while (!(read32(®s->status) & STATUS_RX_FIFO_NOT_EMPTY)) { - if (stopwatch_expired(&sw)) { - printk(BIOS_ERR, "I2C receive timeout\n"); - return -1; - } - } - segment->buf[byte] = read32(®s->cmd_data); - } - - return 0; -} - -int lpss_i2c_transfer(unsigned int bus, - const struct i2c_msg *segments, size_t count) -{ - struct stopwatch sw; - struct lpss_i2c_regs *regs; - size_t byte; - int ret = -1; - - if (count == 0 || !segments) - return -1; - - regs = (struct lpss_i2c_regs *)lpss_i2c_base_address(bus); - if (!regs) { - printk(BIOS_ERR, "I2C bus %u base address not found\n", bus); - return -1; - } - - lpss_i2c_enable(regs); - - if (lpss_i2c_wait_for_bus_idle(regs)) { - printk(BIOS_ERR, "I2C timeout waiting for bus %u idle\n", bus); - goto out; - } - - /* Process each segment */ - while (count--) { - if (CONFIG_SOC_INTEL_COMMON_BLOCK_I2C_DEBUG) - printk(BIOS_DEBUG, "i2c %u:%02x %s %d bytes : ", - bus, segments->slave, - (segments->flags & I2C_M_RD) ? "R" : "W", - segments->len); - - /* Set target slave address */ - write32(®s->target_addr, segments->slave); - - /* Read or write each byte in segment */ - for (byte = 0; byte < segments->len; byte++) { - /* - * Set stop condition on final segment only. - * Repeated start will be automatically generated - * by the controller on R->W or W->R switch. - */ - if (lpss_i2c_transfer_byte(regs, segments, byte, - count == 0) < 0) { - printk(BIOS_ERR, "I2C %s failed: bus %u " - "addr 0x%02x\n", - (segments->flags & I2C_M_RD) ? - "read" : "write", bus, segments->slave); - goto out; - } - } - - if (CONFIG_SOC_INTEL_COMMON_BLOCK_I2C_DEBUG) { - int j; - for (j = 0; j < segments->len; j++) - printk(BIOS_DEBUG, "%02x ", segments->buf[j]); - printk(BIOS_DEBUG, "\n"); - } - - segments++; - } - - /* Wait for interrupt status to indicate transfer is complete */ - stopwatch_init_usecs_expire(&sw, LPSS_I2C_TIMEOUT_US); - while (!(read32(®s->raw_intr_stat) & INTR_STAT_STOP_DET)) { - if (stopwatch_expired(&sw)) { - printk(BIOS_ERR, "I2C stop bit not received\n"); - goto out; - } - } - - /* Read to clear INTR_STAT_STOP_DET */ - read32(®s->clear_stop_det_intr); - - /* Wait for the bus to go idle */ - if (lpss_i2c_wait_for_bus_idle(regs)) { - printk(BIOS_ERR, "I2C timeout waiting for bus %u idle\n", bus); - goto out; - } - - /* Flush the RX FIFO in case it is not empty */ - stopwatch_init_usecs_expire(&sw, 16 * LPSS_I2C_TIMEOUT_US); - while (read32(®s->status) & STATUS_RX_FIFO_NOT_EMPTY) { - if (stopwatch_expired(&sw)) { - printk(BIOS_ERR, "I2C timeout flushing RX FIFO\n"); - goto out; - } - read32(®s->cmd_data); - } - - ret = 0; - -out: - read32(®s->clear_intr); - lpss_i2c_disable(regs); - return ret; -} - -/* Global I2C bus handler, defined in include/device/i2c_simple.h */ -int platform_i2c_transfer(unsigned int bus, struct i2c_msg *msg, int count) -{ - return lpss_i2c_transfer(bus, msg, count < 0 ? 0 : count); -} - -static int lpss_i2c_set_speed_config(unsigned int bus, - const struct lpss_i2c_speed_config *config) -{ - struct lpss_i2c_regs *regs; - void *hcnt_reg, *lcnt_reg; - - regs = (struct lpss_i2c_regs *)lpss_i2c_base_address(bus); - if (!regs || !config) - return -1; - - /* Nothing to do if no values are set */ - if (!config->scl_lcnt && !config->scl_hcnt && !config->sda_hold) - return 0; - - if (config->speed >= I2C_SPEED_HIGH) { - /* High and Fast Ultra speed */ - hcnt_reg = ®s->hs_scl_hcnt; - lcnt_reg = ®s->hs_scl_lcnt; - } else if (config->speed >= I2C_SPEED_FAST) { - /* Fast and Fast-Plus speed */ - hcnt_reg = ®s->fs_scl_hcnt; - lcnt_reg = ®s->fs_scl_lcnt; - } else { - /* Standard speed */ - hcnt_reg = ®s->ss_scl_hcnt; - lcnt_reg = ®s->ss_scl_lcnt; - } - - /* SCL count must be set after the speed is selected */ - if (config->scl_hcnt) - write32(hcnt_reg, config->scl_hcnt); - if (config->scl_lcnt) - write32(lcnt_reg, config->scl_lcnt); - - /* Set SDA Hold Time register */ - if (config->sda_hold) - write32(®s->sda_hold, config->sda_hold); - - return 0; -} - -static int lpss_i2c_gen_config_rise_fall_time(struct lpss_i2c_regs *regs, - enum i2c_speed speed, - const struct lpss_i2c_bus_config *bcfg, - int ic_clk, - struct lpss_i2c_speed_config *config) -{ - const struct i2c_descriptor *bus; - const struct soc_clock *soc; - int fall_cnt, rise_cnt, min_tlow_cnt, min_thigh_cnt, spk_cnt; - int hcnt, lcnt, period_cnt, diff, tot; - int data_hold_time_ns; - - bus = get_bus_descriptor(speed); - soc = get_soc_descriptor(ic_clk); - - if (bus == NULL) { - printk(BIOS_ERR, "lpss_i2c: invalid bus speed %d\n", speed); - return -1; - } - - if (soc == NULL) { - printk(BIOS_ERR, "lpss_i2c: invalid SoC clock speed %d MHz\n", - ic_clk); - return -1; - } - - /* Get the proper spike suppression count based on target speed. */ - if (speed >= I2C_SPEED_HIGH) - spk_cnt = read32(®s->hs_spklen); - else - spk_cnt = read32(®s->fs_spklen); - - /* Find the period, rise, fall, min tlow, and min thigh in terms of - * counts of SoC clock. */ - period_cnt = counts_from_freq(&soc->freq, &bus->freq); - rise_cnt = counts_from_time(&soc->freq, bcfg->rise_time_ns); - fall_cnt = counts_from_time(&soc->freq, bcfg->fall_time_ns); - min_tlow_cnt = counts_from_time(&soc->freq, bus->min_tlow_ns); - min_thigh_cnt = counts_from_time(&soc->freq, bus->min_thigh_ns); - - printk(LPSS_DEBUG, "lpss_i2c: SoC %d/%d ns Bus: %d/%d ns\n", - soc->freq.ticks, soc->freq.ns, bus->freq.ticks, bus->freq.ns); - printk(LPSS_DEBUG, "lpss_i2c: period %d rise %d fall %d tlow %d thigh %d spk %d\n", - period_cnt, rise_cnt, fall_cnt, min_tlow_cnt, min_thigh_cnt, - spk_cnt); - - /* - * Back solve for hcnt and lcnt according to the following equations. - * SCL_High_time = [(HCNT + IC_*_SPKLEN + 7) * ic_clk] + SCL_Fall_time - * SCL_Low_time = [(LCNT + 1) * ic_clk] - SCL_Fall_time + SCL_Rise_time - */ - hcnt = min_thigh_cnt - fall_cnt - 7 - spk_cnt; - lcnt = min_tlow_cnt - rise_cnt + fall_cnt - 1; - - if (hcnt < 0 || lcnt < 0) { - printk(BIOS_ERR, "lpss_i2c: bad counts. hcnt = %d lcnt = %d\n", - hcnt, lcnt); - return -1; - } - - /* Now add things back up to ensure the period is hit. If off, - * split the difference and bias to lcnt for remainder. */ - tot = hcnt + lcnt + 7 + spk_cnt + rise_cnt + 1; - - if (tot < period_cnt) { - diff = (period_cnt - tot) / 2; - hcnt += diff; - lcnt += diff; - tot = hcnt + lcnt + 7 + spk_cnt + rise_cnt + 1; - lcnt += period_cnt - tot; - } - - config->speed = speed; - config->scl_lcnt = lcnt; - config->scl_hcnt = hcnt; - - /* Use internal default unless other value is specified. */ - data_hold_time_ns = DEFAULT_SDA_HOLD_TIME; - if (bcfg->data_hold_time_ns) - data_hold_time_ns = bcfg->data_hold_time_ns; - - config->sda_hold = counts_from_time(&soc->freq, data_hold_time_ns); - - printk(LPSS_DEBUG, "lpss_i2c: hcnt = %d lcnt = %d sda hold = %d\n", - hcnt, lcnt, config->sda_hold); - - return 0; -} - -int lpss_i2c_gen_speed_config(struct lpss_i2c_regs *regs, - enum i2c_speed speed, - const struct lpss_i2c_bus_config *bcfg, - struct lpss_i2c_speed_config *config) -{ - const int ic_clk = CONFIG_SOC_INTEL_COMMON_LPSS_CLOCK_MHZ; - uint16_t hcnt_min, lcnt_min; - int i; - - _Static_assert(CONFIG_SOC_INTEL_COMMON_LPSS_CLOCK_MHZ != 0, - "SOC_INTEL_COMMON_LPSS_CLOCK_MHZ can't be zero!"); - - /* Apply board specific override for this speed if found */ - for (i = 0; i < LPSS_I2C_SPEED_CONFIG_COUNT; i++) { - if (bcfg->speed_config[i].speed != speed) - continue; - memcpy(config, &bcfg->speed_config[i], sizeof(*config)); - return 0; - } - - /* If rise time is set use the time calculation. */ - if (bcfg->rise_time_ns) - return lpss_i2c_gen_config_rise_fall_time(regs, speed, bcfg, - ic_clk, config); - - if (speed >= I2C_SPEED_HIGH) { - /* High speed */ - hcnt_min = MIN_HS_SCL_HIGHTIME; - lcnt_min = MIN_HS_SCL_LOWTIME; - } else if (speed >= I2C_SPEED_FAST_PLUS) { - /* Fast-Plus speed */ - hcnt_min = MIN_FP_SCL_HIGHTIME; - lcnt_min = MIN_FP_SCL_LOWTIME; - } else if (speed >= I2C_SPEED_FAST) { - /* Fast speed */ - hcnt_min = MIN_FS_SCL_HIGHTIME; - lcnt_min = MIN_FS_SCL_LOWTIME; - } else { - /* Standard speed */ - hcnt_min = MIN_SS_SCL_HIGHTIME; - lcnt_min = MIN_SS_SCL_LOWTIME; - } - - config->speed = speed; - config->scl_hcnt = ic_clk * hcnt_min / KHz; - config->scl_lcnt = ic_clk * lcnt_min / KHz; - config->sda_hold = ic_clk * DEFAULT_SDA_HOLD_TIME / KHz; - - return 0; -} - -static int lpss_i2c_set_speed(unsigned int bus, enum i2c_speed speed, - const struct lpss_i2c_bus_config *bcfg) -{ - struct lpss_i2c_regs *regs; - struct lpss_i2c_speed_config config; - uint32_t control; - - /* Clock must be provided by Kconfig */ - regs = (struct lpss_i2c_regs *)lpss_i2c_base_address(bus); - if (!regs || !speed) - return -1; - - control = read32(®s->control); - control &= ~CONTROL_SPEED_MASK; - - if (speed >= I2C_SPEED_HIGH) { - /* High and Fast-Ultra speed share config registers */ - control |= CONTROL_SPEED_HS; - } else if (speed >= I2C_SPEED_FAST) { - /* Fast speed and Fast-Plus */ - control |= CONTROL_SPEED_FS; - } else { - /* Standard speed */ - control |= CONTROL_SPEED_SS; - } - - /* Generate speed config based on clock */ - if (lpss_i2c_gen_speed_config(regs, speed, bcfg, &config) < 0) - return -1; - - /* Select this speed in the control register */ - write32(®s->control, control); - - /* Write the speed config that was generated earlier */ - lpss_i2c_set_speed_config(bus, &config); - - return 0; -} - - -/* - * Initialize this bus controller and set the speed. - * - * The bus speed can be passed in Hz or using values from device/i2c.h and - * will default to I2C_SPEED_FAST if it is not provided. - */ -int lpss_i2c_init(unsigned int bus, const struct lpss_i2c_bus_config *bcfg) -{ - struct lpss_i2c_regs *regs; - enum i2c_speed speed; - - if (!bcfg) - return -1; - - speed = bcfg->speed ? : I2C_SPEED_FAST; - - regs = (struct lpss_i2c_regs *)lpss_i2c_base_address(bus); - if (!regs) { - printk(BIOS_ERR, "I2C bus %u base address not found\n", bus); - return -1; - } - - if (lpss_i2c_disable(regs) < 0) { - printk(BIOS_ERR, "I2C timeout disabling bus %u\n", bus); - return -1; - } - - /* Put controller in master mode with restart enabled */ - write32(®s->control, CONTROL_MASTER_MODE | CONTROL_SLAVE_DISABLE | - CONTROL_RESTART_ENABLE); - - /* Set bus speed to FAST by default */ - if (lpss_i2c_set_speed(bus, speed, bcfg) < 0) { - printk(BIOS_ERR, "I2C failed to set speed for bus %u\n", bus); - return -1; - } - - /* Set RX/TX thresholds to smallest values */ - write32(®s->rx_thresh, 0); - write32(®s->tx_thresh, 0); - - /* Enable stop detection interrupt */ - write32(®s->intr_mask, INTR_STAT_STOP_DET); - - printk(BIOS_INFO, "LPSS I2C bus %u at 0x%p (%u KHz)\n", - bus, regs, speed / KHz); - - return 0; -} |