MIPS: Malta: add suspend state entry code (b6911bba) · Commits · 戴 / test

arch/mips/Kconfig

+6 −0

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		@@ -1671,6 +1671,12 @@ config SYS_HAS_CPU_XLR
		config SYS_HAS_CPU_XLP
		bool

		config MIPS_MALTA_PM
		depends on MIPS_MALTA
		depends on PCI
		bool
		default y

		#
		# CPU may reorder R->R, R->W, W->R, W->W
		# Reordering beyond LL and SC is handled in WEAK_REORDERING_BEYOND_LLSC

arch/mips/include/asm/mach-malta/malta-pm.h

0 → 100644

+37 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2014 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.
		*/

		#ifndef __ASM_MIPS_MACH_MALTA_PM_H__
		#define __ASM_MIPS_MACH_MALTA_PM_H__

		#include <asm/mips-boards/piix4.h>

		#ifdef CONFIG_MIPS_MALTA_PM

		/**
		* mips_pm_suspend - enter a suspend state
		* @state: the state to enter, one of PIIX4_FUNC3IO_PMCNTRL_SUS_TYP_*
		*
		* Enters a suspend state via the Malta's PIIX4. If the state to be entered
		* is one which loses context (eg. SOFF) then this function will never
		* return.
		*/
		extern int mips_pm_suspend(unsigned state);

		#else /* !CONFIG_MIPS_MALTA_PM */

		static inline int mips_pm_suspend(unsigned state)
		{
		return -EINVAL;
		}

		#endif /* !CONFIG_MIPS_MALTA_PM */

		#endif /* __ASM_MIPS_MACH_MALTA_PM_H__ */

arch/mips/mti-malta/Makefile

+2 −0

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		@@ -8,3 +8,5 @@
		obj-y := malta-amon.o malta-display.o malta-init.o \
		malta-int.o malta-memory.o malta-platform.o \
		malta-reset.o malta-setup.o malta-time.o

		obj-$(CONFIG_MIPS_MALTA_PM) += malta-pm.o

arch/mips/mti-malta/malta-pm.c

0 → 100644

+96 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2014 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/init.h>
		#include <linux/io.h>
		#include <linux/pci.h>

		#include <asm/mach-malta/malta-pm.h>

		static struct pci_bus *pm_pci_bus;
		static resource_size_t pm_io_offset;

		int mips_pm_suspend(unsigned state)
		{
		int spec_devid;
		u16 sts;

		if (!pm_pci_bus \|\| !pm_io_offset)
		return -ENODEV;

		/* Ensure the power button status is clear */
		while (1) {
		sts = inw(pm_io_offset + PIIX4_FUNC3IO_PMSTS);
		if (!(sts & PIIX4_FUNC3IO_PMSTS_PWRBTN_STS))
		break;
		outw(sts, pm_io_offset + PIIX4_FUNC3IO_PMSTS);
		}

		/* Enable entry to suspend */
		outw(state \| PIIX4_FUNC3IO_PMCNTRL_SUS_EN,
		pm_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_pci_bus, spec_devid, 0,
		PIIX4_SUSPEND_MAGIC);

		/* Give the system some time to power down */
		mdelay(1000);

		return 0;
		}

		static int __init malta_pm_setup(void)
		{
		struct pci_dev *dev;
		int res, io_region = PCI_BRIDGE_RESOURCES;

		/* Find a reference to the PCI bus */
		pm_pci_bus = pci_find_next_bus(NULL);
		if (!pm_pci_bus) {
		pr_warn("malta-pm: failed to find reference to PCI bus\n");
		return -ENODEV;
		}

		/* Find the PIIX4 PM device */
		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
		PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
		PCI_ANY_ID, NULL);
		if (!dev) {
		pr_warn("malta-pm: failed to find PIIX4 PM\n");
		return -ENODEV;
		}

		/* Request access to the PIIX4 PM IO registers */
		res = pci_request_region(dev, io_region, "PIIX4 PM IO registers");
		if (res) {
		pr_warn("malta-pm: failed to request PM IO registers (%d)\n",
		res);
		pci_dev_put(dev);
		return -ENODEV;
		}

		/* Find the offset to the PIIX4 PM IO registers */
		pm_io_offset = pci_resource_start(dev, io_region);

		pci_dev_put(dev);
		return 0;
		}

		late_initcall(malta_pm_setup);

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