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Commit 93e5eadd authored by Li, Aubrey's avatar Li, Aubrey Committed by H. Peter Anvin
Browse files

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: default avatarAubrey Li <aubrey.li@linux.intel.com>
Link: http://lkml.kernel.org/r/53B0FEEA.3010805@linux.intel.com


Signed-off-by: default avatarLejun Zhu <lejun.zhu@linux.intel.com>
Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 832fcc89

arch/x86/Kconfig

+4 −0
Original line number Diff line number Diff line
@@ -2403,6 +2403,10 @@ config IOSF_MBI 
	default m

	depends on PCI



config PMC_ATOM

	def_bool y

        depends on PCI



source "net/Kconfig"



source "drivers/Kconfig"

arch/x86/include/asm/pmc_atom.h

0 → 100644
+31 −0
Original line number Diff line number Diff line 
/*

 * Intel Atom SOC Power Management Controller Header File

 * 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.

 *

 */



#ifndef PMC_ATOM_H

#define PMC_ATOM_H



/* ValleyView Power Control Unit PCI Device ID */

#define	PCI_DEVICE_ID_VLV_PMC	0x0F1C



/* PMC I/O Registers */

#define	ACPI_BASE_ADDR_OFFSET	0x40

#define	ACPI_BASE_ADDR_MASK	0xFFFFFE00

#define	ACPI_MMIO_REG_LEN	0x100



#define	PM1_CNT			0x4

#define	SLEEP_TYPE_MASK		0xFFFFECFF

#define	SLEEP_TYPE_S5		0x1C00

#define	SLEEP_ENABLE		0x2000

#endif /* PMC_ATOM_H */

arch/x86/kernel/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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

arch/x86/kernel/pmc_atom.c

0 → 100644
+104 −0
Original line number Diff line number Diff line 
/*

 * 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");