diff options
author | Li, Aubrey <aubrey.li@linux.intel.com> | 2014-06-30 14:08:42 +0800 |
---|---|---|
committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-07-25 14:11:29 -0700 |
commit | 93e5eadd1f6e7f45c31aa327c42ac52e4df5ff6f (patch) | |
tree | d72d68d835dc4bf65dea67893cc701c78c31b0d2 /arch/x86/kernel | |
parent | 832fcc899a90cce54eb5e47c7fd099eacc0130da (diff) | |
download | linux-93e5eadd1f6e7f45c31aa327c42ac52e4df5ff6f.tar.bz2 |
x86/platform: New Intel Atom SOC power management controller driver
The Power Management Controller (PMC) controls many of the power
management features present in the Atom SoC. This driver provides
a native power off function via PMC PCI IO port.
On some ACPI hardware-reduced platforms(e.g. ASUS-T100), ACPI sleep
registers are not valid so that (*pm_power_off)() is not hooked by
acpi_power_off(). The power off function in this driver is installed
only when pm_power_off is NULL.
Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Link: http://lkml.kernel.org/r/53B0FEEA.3010805@linux.intel.com
Signed-off-by: Lejun Zhu <lejun.zhu@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
-rw-r--r-- | arch/x86/kernel/pmc_atom.c | 104 |
2 files changed, 105 insertions, 0 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 047f9ff2e36c..bde3993624f1 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -106,6 +106,7 @@ obj-$(CONFIG_EFI) += sysfb_efi.o obj-$(CONFIG_PERF_EVENTS) += perf_regs.o obj-$(CONFIG_TRACING) += tracepoint.o obj-$(CONFIG_IOSF_MBI) += iosf_mbi.o +obj-$(CONFIG_PMC_ATOM) += pmc_atom.o ### # 64 bit specific files diff --git a/arch/x86/kernel/pmc_atom.c b/arch/x86/kernel/pmc_atom.c new file mode 100644 index 000000000000..9eb79f6fc512 --- /dev/null +++ b/arch/x86/kernel/pmc_atom.c @@ -0,0 +1,104 @@ +/* + * Intel Atom SOC Power Management Controller Driver + * Copyright (c) 2014, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/device.h> +#include <linux/io.h> + +#include <asm/pmc_atom.h> + +static u32 acpi_base_addr; + +static void pmc_power_off(void) +{ + u16 pm1_cnt_port; + u32 pm1_cnt_value; + + pr_info("Preparing to enter system sleep state S5\n"); + + pm1_cnt_port = acpi_base_addr + PM1_CNT; + + pm1_cnt_value = inl(pm1_cnt_port); + pm1_cnt_value &= SLEEP_TYPE_MASK; + pm1_cnt_value |= SLEEP_TYPE_S5; + pm1_cnt_value |= SLEEP_ENABLE; + + outl(pm1_cnt_value, pm1_cnt_port); +} + +static int pmc_setup_dev(struct pci_dev *pdev) +{ + /* Obtain ACPI base address */ + pci_read_config_dword(pdev, ACPI_BASE_ADDR_OFFSET, &acpi_base_addr); + acpi_base_addr &= ACPI_BASE_ADDR_MASK; + + /* Install power off function */ + if (acpi_base_addr != 0 && pm_power_off == NULL) + pm_power_off = pmc_power_off; + + return 0; +} + +/* + * Data for PCI driver interface + * + * This data only exists for exporting the supported + * PCI ids via MODULE_DEVICE_TABLE. We do not actually + * register a pci_driver, because lpc_ich will register + * a driver on the same PCI id. + */ +static const struct pci_device_id pmc_pci_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_VLV_PMC) }, + { 0, }, +}; + +MODULE_DEVICE_TABLE(pci, pmc_pci_ids); + +static int __init pmc_atom_init(void) +{ + int err = -ENODEV; + struct pci_dev *pdev = NULL; + const struct pci_device_id *ent; + + /* We look for our device - PCU PMC + * we assume that there is max. one device. + * + * We can't use plain pci_driver mechanism, + * as the device is really a multiple function device, + * main driver that binds to the pci_device is lpc_ich + * and have to find & bind to the device this way. + */ + for_each_pci_dev(pdev) { + ent = pci_match_id(pmc_pci_ids, pdev); + if (ent) { + err = pmc_setup_dev(pdev); + goto out; + } + } + /* Device not found. */ +out: + return err; +} + +module_init(pmc_atom_init); +/* no module_exit, this driver shouldn't be unloaded */ + +MODULE_AUTHOR("Aubrey Li <aubrey.li@linux.intel.com>"); +MODULE_DESCRIPTION("Intel Atom SOC Power Management Controller Interface"); +MODULE_LICENSE("GPL v2"); |