diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/power/reset/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/power/reset/Makefile | 1 | ||||
| -rw-r--r-- | drivers/power/reset/piix4-poweroff.c | 113 |
3 files changed, 124 insertions, 0 deletions
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index c74c3f67b8da..abeb77217a21 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -104,6 +104,16 @@ config POWER_RESET_MSM help Power off and restart support for Qualcomm boards. +config POWER_RESET_PIIX4_POWEROFF + tristate "Intel PIIX4 power-off driver" + depends on PCI + depends on MIPS || COMPILE_TEST + help + This driver supports powering off a system using the Intel PIIX4 + southbridge, for example the MIPS Malta development board. The + southbridge SOff state is entered in response to a request to + power off the system. + config POWER_RESET_LTC2952 bool "LTC2952 PowerPath power-off driver" depends on OF_GPIO diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 1be307c7fc25..11dae3b56ff9 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -10,6 +10,7 @@ obj-$(CONFIG_POWER_RESET_GPIO_RESTART) += gpio-restart.o obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o obj-$(CONFIG_POWER_RESET_IMX) += imx-snvs-poweroff.o obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o +obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o diff --git a/drivers/power/reset/piix4-poweroff.c b/drivers/power/reset/piix4-poweroff.c new file mode 100644 index 000000000000..bacfc95783f0 --- /dev/null +++ b/drivers/power/reset/piix4-poweroff.c @@ -0,0 +1,113 @@ +/* + * Copyright (C) 2016 Imagination Technologies + * Author: Paul Burton <paul.burton@imgtec.com> + * + * 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; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/pm.h> + +static struct pci_dev *pm_dev; +static resource_size_t io_offset; + +enum piix4_pm_io_reg { + PIIX4_FUNC3IO_PMSTS = 0x00, +#define PIIX4_FUNC3IO_PMSTS_PWRBTN_STS BIT(8) + PIIX4_FUNC3IO_PMCNTRL = 0x04, +#define PIIX4_FUNC3IO_PMCNTRL_SUS_EN BIT(13) +#define PIIX4_FUNC3IO_PMCNTRL_SUS_TYP_SOFF (0x0 << 10) +}; + +#define PIIX4_SUSPEND_MAGIC 0x00120002 + +static const int piix4_pm_io_region = PCI_BRIDGE_RESOURCES; + +static void piix4_poweroff(void) +{ + int spec_devid; + u16 sts; + + /* Ensure the power button status is clear */ + while (1) { + sts = inw(io_offset + PIIX4_FUNC3IO_PMSTS); + if (!(sts & PIIX4_FUNC3IO_PMSTS_PWRBTN_STS)) + break; + outw(sts, io_offset + PIIX4_FUNC3IO_PMSTS); + } + + /* Enable entry to suspend */ + outw(PIIX4_FUNC3IO_PMCNTRL_SUS_TYP_SOFF | PIIX4_FUNC3IO_PMCNTRL_SUS_EN, + io_offset + PIIX4_FUNC3IO_PMCNTRL); + + /* If the special cycle occurs too soon this doesn't work... */ + mdelay(10); + + /* + * The PIIX4 will enter the suspend state only after seeing a special + * cycle with the correct magic data on the PCI bus. Generate that + * cycle now. + */ + spec_devid = PCI_DEVID(0, PCI_DEVFN(0x1f, 0x7)); + pci_bus_write_config_dword(pm_dev->bus, spec_devid, 0, + PIIX4_SUSPEND_MAGIC); + + /* Give the system some time to power down, then error */ + mdelay(1000); + pr_emerg("Unable to poweroff system\n"); +} + +static int piix4_poweroff_probe(struct pci_dev *dev, + const struct pci_device_id *id) +{ + int res; + + if (pm_dev) + return -EINVAL; + + /* Request access to the PIIX4 PM IO registers */ + res = pci_request_region(dev, piix4_pm_io_region, + "PIIX4 PM IO registers"); + if (res) { + dev_err(&dev->dev, "failed to request PM IO registers: %d\n", + res); + return res; + } + + pm_dev = dev; + io_offset = pci_resource_start(dev, piix4_pm_io_region); + pm_power_off = piix4_poweroff; + + return 0; +} + +static void piix4_poweroff_remove(struct pci_dev *dev) +{ + if (pm_power_off == piix4_poweroff) + pm_power_off = NULL; + + pci_release_region(dev, piix4_pm_io_region); + pm_dev = NULL; +} + +static const struct pci_device_id piix4_poweroff_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) }, + { 0 }, +}; + +static struct pci_driver piix4_poweroff_driver = { + .name = "piix4-poweroff", + .id_table = piix4_poweroff_ids, + .probe = piix4_poweroff_probe, + .remove = piix4_poweroff_remove, +}; + +module_pci_driver(piix4_poweroff_driver); +MODULE_AUTHOR("Paul Burton <paul.burton@imgtec.com>"); +MODULE_LICENSE("GPL"); |
