From 8a1ee9bf70d1777636b297158882a5f465af66b7 Mon Sep 17 00:00:00 2001 From: Furquan Shaikh Date: Wed, 12 Nov 2014 16:23:00 -0800 Subject: [PATCH] rtc: Add an RTC driver for the TI TPS65913 PMIC. The TPS65913 PMIC has an RTC built into it. This change adds a driver for it which implements the new RTC API. BUG=chrome-os-partner:33764 BRANCH=None TEST=Compiles and boots to kernel prompt on ryu. Timestamps for event log verified across multiple boots. Change-Id: I49ec9b78afc53f1cbd4be09e448cdae6077fb710 Signed-off-by: Patrick Georgi Original-Commit-Id: c16c11e620c830e7a73a2a24fe4823ccea0f3c39 Original-Change-Id: If1d549ea2361d0de6be75fd24b9e9810a6df7457 Original-Signed-off-by: Furquan Shaikh Original-Reviewed-on: https://chromium-review.googlesource.com/229414 Original-Reviewed-by: Aaron Durbin Original-Tested-by: Furquan Shaikh Original-Commit-Queue: Furquan Shaikh Reviewed-on: http://review.coreboot.org/9425 Reviewed-by: Paul Menzel Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer --- src/drivers/ti/Kconfig | 1 + src/drivers/ti/Makefile.inc | 2 + src/drivers/ti/tps65913/Kconfig | 35 ++++++ src/drivers/ti/tps65913/Makefile.inc | 20 ++++ src/drivers/ti/tps65913/tps65913rtc.c | 155 ++++++++++++++++++++++++++ 5 files changed, 213 insertions(+) create mode 100644 src/drivers/ti/tps65913/Kconfig create mode 100644 src/drivers/ti/tps65913/Makefile.inc create mode 100644 src/drivers/ti/tps65913/tps65913rtc.c diff --git a/src/drivers/ti/Kconfig b/src/drivers/ti/Kconfig index b3aded8848..42ead039be 100644 --- a/src/drivers/ti/Kconfig +++ b/src/drivers/ti/Kconfig @@ -18,3 +18,4 @@ ## source src/drivers/ti/tps65090/Kconfig +source src/drivers/ti/tps65913/Kconfig diff --git a/src/drivers/ti/Makefile.inc b/src/drivers/ti/Makefile.inc index c0ed9c0d3e..037da94f58 100644 --- a/src/drivers/ti/Makefile.inc +++ b/src/drivers/ti/Makefile.inc @@ -2,6 +2,7 @@ ## This file is part of the coreboot project. ## ## Copyright (C) 2012 The Chromium OS Authors. +## Copyright 2014 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 @@ -18,3 +19,4 @@ ## subdirs-$(CONFIG_DRIVER_TI_TPS65090) += tps65090/ +subdirs-$(CONFIG_DRIVERS_TI_TPS65913) += tps65913/ diff --git a/src/drivers/ti/tps65913/Kconfig b/src/drivers/ti/tps65913/Kconfig new file mode 100644 index 0000000000..bd24baeeba --- /dev/null +++ b/src/drivers/ti/tps65913/Kconfig @@ -0,0 +1,35 @@ +## +## This file is part of the coreboot project. +## +## Copyright 2014 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. +## +## You should have received a copy of the GNU General Public License +## along with this program; if not, write to the Free Software +## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +## + +config DRIVERS_TI_TPS65913 + bool "TI TPS65913 support" + default n + +config DRIVERS_TI_TPS65913_RTC + bool "TI TPS65913 RTC support" + default n + select DRIVERS_TI_TPS65913 + +config DRIVERS_TI_TPS65913_RTC_BUS + int "TI TPS65913 RTC bus" + depends on DRIVERS_TI_TPS65913_RTC + +config DRIVERS_TI_TPS65913_RTC_ADDR + hex "TI TPS65913 RTC chip address" + depends on DRIVERS_TI_TPS65913_RTC diff --git a/src/drivers/ti/tps65913/Makefile.inc b/src/drivers/ti/tps65913/Makefile.inc new file mode 100644 index 0000000000..272b026383 --- /dev/null +++ b/src/drivers/ti/tps65913/Makefile.inc @@ -0,0 +1,20 @@ +## +## This file is part of the coreboot project. +## +## Copyright 2014 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. +## +## You should have received a copy of the GNU General Public License +## along with this program; if not, write to the Free Software +## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +## + +ramstage-$(CONFIG_DRIVERS_TI_TPS65913_RTC) += tps65913rtc.c diff --git a/src/drivers/ti/tps65913/tps65913rtc.c b/src/drivers/ti/tps65913/tps65913rtc.c new file mode 100644 index 0000000000..46dd4f9dd0 --- /dev/null +++ b/src/drivers/ti/tps65913/tps65913rtc.c @@ -0,0 +1,155 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2014 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include +#include +#include +#include +#include + +enum TPS65913_RTC_REG { + TPS65913_SECONDS_REG = 0x00, + TPS65913_MINUTES_REG = 0x01, + TPS65913_HOURS_REG = 0x02, + TPS65913_DAYS_REG = 0x03, + TPS65913_MONTHS_REG = 0x04, + TPS65913_YEARS_REG = 0x05, + TPS65913_WEEKS_REG = 0x06, + TPS65913_RTC_CTRL_REG = 0x10, + TPS65913_RTC_STATUS_REG = 0x11, + TPS65913_RTC_INTERRUPS_REG = 0x12, +}; + +enum { + TPS65913_RTC_CTRL_STOP = (1 << 0), + TPS65913_RTC_CTRL_GET_TIME = (1 << 6), + + TPS65913_RTC_STATUS_RUN = (1 << 1), + TPS65913_RTC_RUNNING = (1 << 1), + TPS65913_RTC_FROZEN = (0 << 1), +}; + +static inline uint8_t tps65913_read(enum TPS65913_RTC_REG reg) +{ + uint8_t val; + i2c_readb(CONFIG_DRIVERS_TI_TPS65913_RTC_BUS, + CONFIG_DRIVERS_TI_TPS65913_RTC_ADDR, reg, &val); + return val; +} + +static inline void tps65913_write(enum TPS65913_RTC_REG reg, uint8_t val) +{ + i2c_writeb(CONFIG_DRIVERS_TI_TPS65913_RTC_BUS, + CONFIG_DRIVERS_TI_TPS65913_RTC_ADDR, reg, val); +} + +static void tps65913_rtc_ctrl_clear(uint8_t bit) +{ + uint8_t control = tps65913_read(TPS65913_RTC_CTRL_REG); + + control &= ~bit; + tps65913_write(TPS65913_RTC_CTRL_REG, control); +} + +static void tps65913_rtc_ctrl_set(uint8_t bit) +{ + uint8_t control = tps65913_read(TPS65913_RTC_CTRL_REG); + + control |= TPS65913_RTC_CTRL_GET_TIME; + tps65913_write(TPS65913_RTC_CTRL_REG, control); +} + +static int tps65913_is_rtc_running(void) +{ + uint8_t status = tps65913_read(TPS65913_RTC_STATUS_REG); + return ((status & TPS65913_RTC_STATUS_RUN) == TPS65913_RTC_RUNNING); +} + +/* + * This function ensures that current time is copied to shadow registers. Then a + * normal read on TC registers reads from the shadow instead of current TC + * registers. This helps prevent the accidental change in counters while + * reading. In order to ensure that the current TC registers are copied into + * shadow registers, GET_TIME bit needs to be set to 0 and then to 1. + */ +static void tps65913_rtc_shadow(void) +{ + tps65913_rtc_ctrl_clear(TPS65913_RTC_CTRL_GET_TIME); + tps65913_rtc_ctrl_set(TPS65913_RTC_CTRL_GET_TIME); +} + +static int tps65913_rtc_stop(void) +{ + /* Clearing stop bit freezes RTC */ + tps65913_rtc_ctrl_clear(TPS65913_RTC_CTRL_STOP); + + if (tps65913_is_rtc_running()) { + printk(BIOS_ERR, "Could not stop RTC\n"); + return 1; + } + + return 0; +} + +static int tps65913_rtc_start(void) +{ + /* Setting stop bit starts RTC */ + tps65913_rtc_ctrl_set(TPS65913_RTC_CTRL_STOP); + + if (!tps65913_is_rtc_running()) { + printk(BIOS_ERR, "Could not start RTC\n"); + return 1; + } + + return 0; +} + +int rtc_set(const struct rtc_time *time) +{ + /* Before setting the time, ensure that rtc is stopped */ + if (tps65913_rtc_stop()) + return 1; + + tps65913_write(TPS65913_SECONDS_REG, bin2bcd(time->sec)); + tps65913_write(TPS65913_MINUTES_REG, bin2bcd(time->min)); + tps65913_write(TPS65913_HOURS_REG, bin2bcd(time->hour)); + tps65913_write(TPS65913_DAYS_REG, bin2bcd(time->mday)); + tps65913_write(TPS65913_MONTHS_REG, bin2bcd(time->mon)); + tps65913_write(TPS65913_YEARS_REG, bin2bcd(time->year)); + + /* Re-start rtc */ + if (tps65913_rtc_start()) + return 1; + + return 0; +} + +int rtc_get(struct rtc_time *time) +{ + tps65913_rtc_shadow(); + + time->sec = bcd2bin(tps65913_read(TPS65913_SECONDS_REG) & 0x7f); + time->min = bcd2bin(tps65913_read(TPS65913_MINUTES_REG) & 0x7f); + time->hour = bcd2bin(tps65913_read(TPS65913_HOURS_REG) & 0x3f); + time->mday = bcd2bin(tps65913_read(TPS65913_DAYS_REG) & 0x3f); + time->mon = bcd2bin(tps65913_read(TPS65913_MONTHS_REG) & 0x1f); + time->year = bcd2bin(tps65913_read(TPS65913_YEARS_REG) & 0xff); + + return 0; +}