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[2/2] x86 platform driver: intelligent power sharing driver

Message ID 20100514154114.4f70f6c0@virtuousgeek.org (mailing list archive)
State Deferred, archived
Headers show

Commit Message

Jesse Barnes May 14, 2010, 10:41 p.m. UTC
None
diff mbox

Patch

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index e631dbe..c2f972c 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -516,4 +516,14 @@  config ACPI_CMPC
 	  keys as input device, backlight device, tablet and accelerometer
 	  devices.
 
+config INTEL_IPS
+	tristate "Intel Intelligent Power Sharing"
+	depends on ACPI
+	---help---
+	  Intel Calpella platforms support dynamic power sharing between the
+	  CPU and GPU, maximizing performance in a given TDP.  This driver,
+	  along with the CPU frequency and i915 drivers, provides that
+	  functionality.  If in doubt, say Y here; it will only load on
+	  supported platforms.
+
 endif # X86_PLATFORM_DEVICES
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 9cd9fa0..08560ff 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -24,3 +24,4 @@  obj-$(CONFIG_ACPI_ASUS)		+= asus_acpi.o
 obj-$(CONFIG_TOPSTAR_LAPTOP)	+= topstar-laptop.o
 obj-$(CONFIG_ACPI_TOSHIBA)	+= toshiba_acpi.o
 obj-$(CONFIG_TOSHIBA_BT_RFKILL)	+= toshiba_bluetooth.o
+obj-$(CONFIG_INTEL_IPS)		+= intel_ips.o
\ No newline at end of file
diff --git a/drivers/platform/x86/intel_ips.c b/drivers/platform/x86/intel_ips.c
new file mode 100644
index 0000000..c675bf2
--- /dev/null
+++ b/drivers/platform/x86/intel_ips.c
@@ -0,0 +1,1655 @@ 
+/*
+ * Copyright (c) 2009-2010 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.
+ *
+ * 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.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Authors:
+ *	Jesse Barnes <jbarnes@virtuousgeek.org>
+ */
+
+/*
+ * Some Intel Ibex Peak based platforms support so-called "intelligent
+ * power sharing", which allows the CPU and GPU to cooperate to maximize
+ * performance within a given TDP (thermal design point).  This driver
+ * performs the coordination between the CPU and GPU, monitors thermal and
+ * power statistics in the platform, and initializes power monitoring
+ * hardware.  It also provides a few tunables to control behavior.  Its
+ * primary purpose is to safely allow CPU and GPU turbo modes to be enabled
+ * by tracking power and thermal budget; secondarily it can boost turbo
+ * performance by allocating more power or thermal budget to the CPU or GPU
+ * based on available headroom and activity.
+ *
+ * The basic algorithm is driven by a 5s moving average of tempurature.  If
+ * thermal headroom is available, the CPU and/or GPU power clamps may be
+ * adjusted upwards.  If we hit the thermal ceiling or a thermal trigger,
+ * we scale back the clamp.  Aside from trigger events (when we're critically
+ * close or over our TDP) we don't adjust the clamps more than once every
+ * five seconds.
+ *
+ * The thermal device (device 31, function 6) has a set of registers that
+ * are updated by the ME firmware.  The ME should also take the clamp values
+ * written to those registers and write them to the CPU, but we currently
+ * bypass that functionality and write the CPU MSR directly.
+ *
+ * UNSUPPORTED:
+ *   - dual MCP configs
+ *
+ * TODO:
+ *   - handle CPU hotplug
+ *   - provide turbo enable/disable api
+ *   - make sure we can write turbo enable/disable reg based on MISC_EN
+ *
+ * Related documents:
+ *   - CDI 403777, 403778 - Auburndale EDS vol 1 & 2
+ *   - CDI 401376 - Ibex Peak EDS
+ *   - ref 26037, 26641 - IPS BIOS spec
+ *   - ref 26489 - Nehalem BIOS writer's guide
+ *   - ref 26921 - Ibex Peak BIOS Specification
+ */
+
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <linux/tick.h>
+#include <linux/timer.h>
+#include <drm/i915_drm.h>
+#include <asm/msr.h>
+#include <asm/processor.h>
+
+#define PCI_DEVICE_ID_INTEL_THERMAL_SENSOR 0x3b32
+
+/*
+ * Package level MSRs for monitor/control
+ */
+#define PLATFORM_INFO	0xce
+#define   PLATFORM_TDP		(1<<29)
+#define   PLATFORM_RATIO	(1<<28)
+
+#define IA32_MISC_ENABLE	0x1a0
+#define   IA32_MISC_TURBO_EN	(1ULL<<38)
+
+#define TURBO_POWER_CURRENT_LIMIT	0x1ac
+#define   TURBO_TDC_OVR_EN	(1UL<<31)
+#define   TURBO_TDC_MASK	(0x000000007fff0000UL)
+#define   TURBO_TDC_SHIFT	(16)
+#define   TURBO_TDP_OVR_EN	(1UL<<15)
+#define   TURBO_TDP_MASK	(0x0000000000003fffUL)
+
+/*
+ * Core/thread MSRs for monitoring
+ */
+#define IA32_PERF_CTL		0x199
+#define   IA32_PERF_TURBO_DIS	(1ULL<<32)
+
+/*
+ * Thermal PCI device regs
+ */
+#define THM_CFG_TBAR	0x10
+#define THM_CFG_TBAR_HI	0x14
+
+#define THM_TSIU	0x00
+#define THM_TSE		0x01
+#define   TSE_EN	0xb8
+#define THM_TSS		0x02
+#define THM_TSTR	0x03
+#define THM_TSTTP	0x04
+#define THM_TSCO	0x08
+#define THM_TSES	0x0c
+#define THM_TSGPEN	0x0d
+#define   TSGPEN_HOT_LOHI	(1<<1)
+#define   TSGPEN_CRIT_LOHI	(1<<2)
+#define THM_TSPC	0x0e
+#define THM_PPEC	0x10
+#define THM_CTA		0x12
+#define THM_PTA		0x14
+#define   PTA_SLOPE_MASK	(0xff00)
+#define   PTA_SLOPE_SHIFT	8
+#define   PTA_OFFSET_MASK	(0x00ff)
+#define THM_MGTA	0x16
+#define   MGTA_SLOPE_MASK	(0xff00)
+#define   MGTA_SLOPE_SHIFT	8
+#define   MGTA_OFFSET_MASK	(0x00ff)
+#define THM_TRC		0x1a
+#define   TRC_CORE2_EN	(1<<15)
+#define   TRC_THM_EN	(1<<12)
+#define   TRC_C6_WAR	(1<<8)
+#define   TRC_CORE1_EN	(1<<7)
+#define   TRC_CORE_PWR	(1<<6)
+#define   TRC_PCH_EN	(1<<5)
+#define   TRC_MCH_EN	(1<<4)
+#define   TRC_DIMM4	(1<<3)
+#define   TRC_DIMM3	(1<<2)
+#define   TRC_DIMM2	(1<<1)
+#define   TRC_DIMM1	(1<<0)
+#define THM_TES		0x20
+#define THM_TEN		0x21
+#define   TEN_UPDATE_EN	1
+#define THM_PSC		0x24
+#define   PSC_NTG	(1<<0) /* No GFX turbo support */
+#define   PSC_NTPC	(1<<1) /* No CPU turbo support */
+#define   PSC_PP_DEF	(0<<2) /* Perf policy up to driver */
+#define   PSP_PP_PC	(1<<2) /* BIOS prefers CPU perf */
+#define   PSP_PP_BAL	(2<<2) /* BIOS wants balanced perf */
+#define   PSP_PP_GFX	(3<<2) /* BIOS prefers GFX perf */
+#define   PSP_PBRT	(1<<4) /* BIOS run time support */
+#define THM_CTV1	0x30
+#define   CTV_TEMP_ERROR (1<<15)
+#define   CTV_TEMP_MASK	0x3f
+#define   CTV_
+#define THM_CTV2	0x32
+#define THM_CEC		0x34 /* undocumented power accumulator in joules */
+#define THM_AE		0x3f
+#define THM_HTS		0x50 /* 32 bits */
+#define   HTS_PCPL_MASK	(0x7fe00000)
+#define   HTS_PCPL_SHIFT 21
+#define   HTS_GPL_MASK  (0x001ff000)
+#define   HTS_GPL_SHIFT 12
+#define   HTS_PP_MASK	(0x00000c00)
+#define   HTS_PP_SHIFT  10
+#define   HTS_PP_DEF	0
+#define   HTS_PP_PROC	1
+#define   HTS_PP_BAL	2
+#define   HTS_PP_GFX	3
+#define   HTS_PCTD_DIS	(1<<9)
+#define   HTS_GTD_DIS	(1<<8)
+#define   HTS_PTL_MASK  (0x000000fe)
+#define   HTS_PTL_SHIFT 1
+#define   HTS_NVV	(1<<0)
+#define THM_HTSHI	0x54 /* 16 bits */
+#define   HTS2_PPL_MASK		(0x03ff)
+#define   HTS2_PRST_MASK	(0x3c00)
+#define   HTS2_PRST_SHIFT	10
+#define   HTS2_PRST_UNLOADED	0
+#define   HTS2_PRST_RUNNING	1
+#define   HTS2_PRST_TDISOP	2 /* turbo disabled due to power */
+#define   HTS2_PRST_TDISHT	3 /* turbo disabled due to high temp */
+#define   HTS2_PRST_TDISUSR	4 /* user disabled turbo */
+#define   HTS2_PRST_TDISPLAT	5 /* platform disabled turbo */
+#define   HTS2_PRST_TDISPM	6 /* power management disabled turbo */
+#define   HTS2_PRST_TDISERR	7 /* some kind of error disabled turbo */
+#define THM_PTL		0x56
+#define THM_MGTV	0x58
+#define   TV_MASK	0x000000000000ff00
+#define   TV_SHIFT	8
+#define THM_PTV		0x60
+#define   PTV_MASK	0x00ff
+#define THM_MMGPC	0x64
+#define THM_MPPC	0x66
+#define THM_MPCPC	0x68
+#define THM_TSPIEN	0x82
+#define   TSPIEN_AUX_LOHI	(1<<0)
+#define   TSPIEN_HOT_LOHI	(1<<1)
+#define   TSPIEN_CRIT_LOHI	(1<<2)
+#define   TSPIEN_AUX2_LOHI	(1<<3)
+#define THM_TSLOCK	0x83
+#define THM_ATR		0x84
+#define THM_TOF		0x87
+#define THM_STS		0x98
+#define   STS_PCPL_MASK		(0x7fe00000)
+#define   STS_PCPL_SHIFT	21
+#define   STS_GPL_MASK		(0x001ff000)
+#define   STS_GPL_SHIFT		12
+#define   STS_PP_MASK		(0x00000c00)
+#define   STS_PP_SHIFT  	10
+#define   STS_PP_DEF		0
+#define   STS_PP_PROC		1
+#define   STS_PP_BAL		2
+#define   STS_PP_GFX		3
+#define   STS_PCTD_DIS		(1<<9)
+#define   STS_GTD_DIS		(1<<8)
+#define   STS_PTL_MASK  	(0x000000fe)
+#define   STS_PTL_SHIFT 	1
+#define   STS_NVV		(1<<0)
+#define THM_SEC		0x9c
+#define   SEC_ACK	(1<<0)
+#define THM_TC3		0xa4
+#define THM_TC1		0xa8
+#define   STS_PPL_MASK		(0x0003ff00)
+#define   STS_PPL_SHIFT		16
+#define THM_TC2		0xac
+#define THM_DTV		0xb0
+#define THM_ITV		0xd8
+#define   ITV_ME_SEQNO_MASK 0x000f0000 /* ME should update every ~200ms */
+#define   ITV_ME_SEQNO_SHIFT (16)
+#define   ITV_MCH_TEMP_MASK 0x0000ff00
+#define   ITV_MCH_TEMP_SHIFT (8)
+#define   ITV_PCH_TEMP_MASK 0x000000ff
+
+#define thm_readb(off) readb(ips->regmap + (off))
+#define thm_readw(off) readw(ips->regmap + (off))
+#define thm_readl(off) readl(ips->regmap + (off))
+#define thm_readq(off) readq(ips->regmap + (off))
+
+#define thm_writeb(off, val) writeb((val), ips->regmap + (off))
+#define thm_writew(off, val) writew((val), ips->regmap + (off))
+#define thm_writel(off, val) writel((val), ips->regmap + (off))
+
+static const int IPS_ADJUST_PERIOD = 5000; /* ms */
+
+/* For initial average collection */
+static const int IPS_SAMPLE_PERIOD = 200; /* ms */
+static const int IPS_SAMPLE_WINDOW = 5000; /* 5s moving window of samples */
+#define IPS_SAMPLE_COUNT (IPS_SAMPLE_WINDOW / IPS_SAMPLE_PERIOD)
+
+/* Per-SKU limits */
+struct ips_mcp_limits {
+	int cpu_family;
+	int cpu_model; /* includes extended model... */
+	int mcp_power_limit; /* mW units */
+	int core_power_limit;
+	int mch_power_limit;
+	int core_temp_limit; /* degrees C */
+	int mch_temp_limit;
+};
+
+/* Max temps are -10 degrees C to avoid PROCHOT# */
+
+struct ips_mcp_limits ips_sv_limits = {
+	.mcp_power_limit = 35000,
+	.core_power_limit = 29000,
+	.mch_power_limit = 20000,
+	.core_temp_limit = 95,
+	.mch_temp_limit = 90
+};
+
+struct ips_mcp_limits ips_lv_limits = {
+	.mcp_power_limit = 25000,
+	.core_power_limit = 21000,
+	.mch_power_limit = 13000,
+	.core_temp_limit = 95,
+	.mch_temp_limit = 90
+};
+
+struct ips_mcp_limits ips_ulv_limits = {
+	.mcp_power_limit = 18000,
+	.core_power_limit = 14000,
+	.mch_power_limit = 11000,
+	.core_temp_limit = 95,
+	.mch_temp_limit = 90
+};
+
+struct ips_driver {
+	struct pci_dev *dev;
+	void *regmap;
+	struct task_struct *monitor;
+	struct task_struct *adjust;
+	struct dentry *debug_root;
+
+	/* Average CPU core temps (all averages in .01 degrees C for precision) */
+	u16 ctv1_avg_temp;
+	u16 ctv2_avg_temp;
+	/* GMCH average */
+	u16 mch_avg_temp;
+	/* Average for the CPU (both cores?) */
+	u16 mcp_avg_temp;
+	/* Average power consumption (in mW) */
+	u32 cpu_avg_power;
+	u32 mch_avg_power;
+
+	/* Offset values */
+	u16 cta_val;
+	u16 pta_val;
+	u16 mgta_val;
+
+	/* Maximums & prefs, protected by turbo status lock */
+	spinlock_t turbo_status_lock;
+	u16 mcp_temp_limit;
+	u16 mcp_power_limit;
+	u16 core_power_limit;
+	u16 mch_power_limit;
+	bool cpu_turbo_enabled;
+	bool __cpu_turbo_on;
+	bool gpu_turbo_enabled;
+	bool __gpu_turbo_on;
+	bool gpu_preferred;
+	bool poll_turbo_status;
+	bool second_cpu;
+	struct ips_mcp_limits *limits;
+
+	/* Optional MCH interfaces for if i915 is in use */
+	unsigned long (*read_mch_val)(void);
+	bool (*gpu_raise)(void);
+	bool (*gpu_lower)(void);
+	bool (*gpu_busy)(void);
+	bool (*gpu_turbo_disable)(void);
+
+	/* For restoration at unload */
+	u64 orig_turbo_limit;
+	u64 orig_turbo_ratios;
+};
+
+/**
+ * ips_cpu_busy - is CPU busy?
+ * @ips: IPS driver struct
+ *
+ * Check CPU for load to see whether we should increase its thermal budget.
+ *
+ * RETURNS:
+ * True if the CPU could use more power, false otherwise.
+ */
+static bool ips_cpu_busy(struct ips_driver *ips)
+{
+	if ((avenrun[0] >> FSHIFT) > 1)
+		return true;
+
+	return false;
+}
+
+/**
+ * ips_cpu_raise - raise CPU power clamp
+ * @ips: IPS driver struct
+ *
+ * Raise the CPU power clamp by %IPS_CPU_STEP, in accordance with TDP for
+ * this platform.
+ *
+ * We do this by adjusting the TURBO_POWER_CURRENT_LIMIT MSR upwards (as
+ * long as we haven't hit the TDP limit for the SKU).
+ */
+static void ips_cpu_raise(struct ips_driver *ips)
+{
+	u64 turbo_override;
+	u16 cur_tdp_limit, new_tdp_limit;
+
+	if (!ips->cpu_turbo_enabled)
+		return;
+
+	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+
+	cur_tdp_limit = turbo_override & TURBO_TDP_MASK;
+	new_tdp_limit = cur_tdp_limit + 8; /* 1W increase */
+
+	/* Clamp to SKU TDP limit */
+	if (((new_tdp_limit * 10) / 8) > ips->core_power_limit)
+		new_tdp_limit = cur_tdp_limit;
+
+	thm_writew(THM_MPCPC, (new_tdp_limit * 10) / 8);
+
+	turbo_override |= TURBO_TDC_OVR_EN | TURBO_TDC_OVR_EN;
+	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+
+	turbo_override &= ~TURBO_TDP_MASK;
+	turbo_override |= new_tdp_limit;
+
+	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+}
+
+/**
+ * ips_cpu_lower - lower CPU power clamp
+ * @ips: IPS driver struct
+ *
+ * Lower CPU power clamp b %IPS_CPU_STEP if possible.
+ *
+ * We do this by adjusting the TURBO_POWER_CURRENT_LIMIT MSR down, going
+ * as low as the platform limits will allow (though we could go lower there
+ * wouldn't be much point).
+ */
+static void ips_cpu_lower(struct ips_driver *ips)
+{
+	u64 turbo_override;
+	u16 cur_limit, new_limit;
+
+	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+
+	cur_limit = turbo_override & TURBO_TDP_MASK;
+	new_limit = cur_limit - 8; /* 1W decrease */
+
+	/* Clamp to SKU TDP limit */
+	if (((new_limit * 10) / 8) < (ips->orig_turbo_limit & TURBO_TDP_MASK))
+		new_limit = ips->orig_turbo_limit & TURBO_TDP_MASK;
+
+	thm_writew(THM_MPCPC, (new_limit * 10) / 8);
+
+	turbo_override |= TURBO_TDC_OVR_EN | TURBO_TDC_OVR_EN;
+	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+
+	turbo_override &= ~TURBO_TDP_MASK;
+	turbo_override |= new_limit;
+
+	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+}
+
+/**
+ * do_enable_cpu_turbo - internal turbo enable function
+ * @data: unused
+ *
+ * Internal function for actually updating MSRs.  When we enable/disable
+ * turbo, we need to do it on each CPU; this function is the one called
+ * by on_each_cpu() when needed.
+ */
+static void do_enable_cpu_turbo(void *data)
+{
+	u64 perf_ctl;
+
+	rdmsrl(IA32_PERF_CTL, perf_ctl);
+	if (perf_ctl & IA32_PERF_TURBO_DIS) {
+		perf_ctl &= ~IA32_PERF_TURBO_DIS;
+		wrmsrl(IA32_PERF_CTL, perf_ctl);
+	}
+}
+
+/**
+ * ips_enable_cpu_turbo - enable turbo mode on all CPUs
+ * @ips: IPS driver struct
+ *
+ * Enable turbo mode by clearing the disable bit in IA32_PERF_CTL on
+ * all logical threads.
+ */
+static void ips_enable_cpu_turbo(struct ips_driver *ips)
+{
+	/* Already on, no need to mess with MSRs */
+	if (ips->__cpu_turbo_on)
+		return;
+
+	on_each_cpu(do_enable_cpu_turbo, ips, 1);
+
+	ips->__cpu_turbo_on = true;
+}
+
+/**
+ * do_disable_cpu_turbo - internal turbo disable function
+ * @data: unused
+ *
+ * Internal function for actually updating MSRs.  When we enable/disable
+ * turbo, we need to do it on each CPU; this function is the one called
+ * by on_each_cpu() when needed.
+ */
+static void do_disable_cpu_turbo(void *data)
+{
+	u64 perf_ctl;
+
+	rdmsrl(IA32_PERF_CTL, perf_ctl);
+	if (!(perf_ctl & IA32_PERF_TURBO_DIS)) {
+		perf_ctl |= IA32_PERF_TURBO_DIS;
+		wrmsrl(IA32_PERF_CTL, perf_ctl);
+	}
+}
+
+/**
+ * ips_disable_cpu_turbo - disable turbo mode on all CPUs
+ * @ips: IPS driver struct
+ *
+ * Disable turbo mode by setting the disable bit in IA32_PERF_CTL on
+ * all logical threads.
+ */
+static void ips_disable_cpu_turbo(struct ips_driver *ips)
+{
+	/* Already off, leave it */
+	if (!ips->__cpu_turbo_on)
+		return;
+
+	on_each_cpu(do_disable_cpu_turbo, ips, 1);
+
+	ips->__cpu_turbo_on = false;
+}
+
+/**
+ * ips_gpu_busy - is GPU busy?
+ * @ips: IPS driver struct
+ *
+ * Check GPU for load to see whether we should increase its thermal budget.
+ * We need to call into the i915 driver in this case.
+ *
+ * RETURNS:
+ * True if the GPU could use more power, false otherwise.
+ */
+static bool ips_gpu_busy(struct ips_driver *ips)
+{
+	return false;
+}
+
+/**
+ * ips_gpu_raise - raise GPU power clamp
+ * @ips: IPS driver struct
+ *
+ * Raise the GPU frequency/power if possible.  We need to call into the
+ * i915 driver in this case.
+ */
+static void ips_gpu_raise(struct ips_driver *ips)
+{
+	if (!ips->gpu_turbo_enabled)
+		return;
+
+	if (!ips->gpu_raise())
+		ips->gpu_turbo_enabled = false;
+
+	return;
+}
+
+/**
+ * ips_gpu_lower - lower GPU power clamp
+ * @ips: IPS driver struct
+ *
+ * Lower GPU frequency/power if possible.  Need to call i915.
+ */
+static void ips_gpu_lower(struct ips_driver *ips)
+{
+	if (!ips->gpu_turbo_enabled)
+		return;
+
+	if (!ips->gpu_lower())
+		ips->gpu_turbo_enabled = false;
+
+	return;
+}
+
+/**
+ * ips_enable_gpu_turbo - notify the gfx driver turbo is available
+ * @ips: IPS driver struct
+ *
+ * Call into the graphics driver indicating that it can safely use
+ * turbo mode.
+ */
+static void ips_enable_gpu_turbo(struct ips_driver *ips)
+{
+	if (ips->__gpu_turbo_on)
+		return;
+	ips->__gpu_turbo_on = true;
+}
+
+/**
+ * ips_disable_gpu_turbo - notify the gfx driver to disable turbo mode
+ * @ips: IPS driver struct
+ *
+ * Request that the graphics driver disable turbo mode.
+ */
+static void ips_disable_gpu_turbo(struct ips_driver *ips)
+{
+	/* Avoid calling i915 if turbo is already disabled */
+	if (!ips->__gpu_turbo_on)
+		return;
+
+	if (!ips->gpu_turbo_disable())
+		dev_err(&ips->dev->dev, "failed to disable graphis turbo\n");
+	else
+		ips->__gpu_turbo_on = false;
+}
+
+/**
+ * mcp_exceeded - check whether we're outside our thermal & power limits
+ * @ips: IPS driver struct
+ *
+ * Check whether the MCP is over its thermal or power budget.
+ */
+static bool mcp_exceeded(struct ips_driver *ips)
+{
+	unsigned long flags;
+	bool ret = false;
+
+	spin_lock_irqsave(&ips->turbo_status_lock, flags);
+	if (ips->mcp_avg_temp > (ips->mcp_temp_limit * 100))
+		ret = true;
+	if (ips->cpu_avg_power + ips->mch_avg_power > ips->mcp_power_limit)
+		ret = true;
+	spin_unlock_irqrestore(&ips->turbo_status_lock, flags);
+
+	if (ret)
+		dev_warn(&ips->dev->dev,
+			 "MCP power or thermal limit exceeded\n");
+
+	return ret;
+}
+
+/**
+ * cpu_exceeded - check whether a CPU core is outside its limits
+ * @ips: IPS driver struct
+ * @cpu: CPU number to check
+ *
+ * Check a given CPU's average temp or power is over its limit.
+ */
+static bool cpu_exceeded(struct ips_driver *ips, int cpu)
+{
+	unsigned long flags;
+	int avg;
+	bool ret = false;
+
+	spin_lock_irqsave(&ips->turbo_status_lock, flags);
+	avg = cpu ? ips->ctv2_avg_temp : ips->ctv1_avg_temp;
+	if (avg > (ips->limits->core_temp_limit * 100))
+		ret = true;
+	if (ips->cpu_avg_power > ips->core_power_limit)
+		ret = true;
+	spin_unlock_irqrestore(&ips->turbo_status_lock, flags);
+
+	if (ret)
+		dev_warn(&ips->dev->dev,
+			 "CPU power or thermal limit exceeded\n");
+
+	return ret;
+}
+
+/**
+ * mch_exceeded - check whether the GPU is over budget
+ * @ips: IPS driver struct
+ *
+ * Check the MCH temp & power against their maximums.
+ */
+static bool mch_exceeded(struct ips_driver *ips)
+{
+	unsigned long flags;
+	bool ret = false;
+
+	spin_lock_irqsave(&ips->turbo_status_lock, flags);
+	if (ips->mch_avg_temp > (ips->limits->mch_temp_limit * 100))
+		ret = true;
+	spin_unlock_irqrestore(&ips->turbo_status_lock, flags);
+
+	return ret;
+}
+
+/**
+ * update_turbo_limits - get various limits & settings from regs
+ * @ips: IPS driver struct
+ *
+ * Update the IPS power & temp limits, along with turbo enable flags,
+ * based on latest register contents.
+ *
+ * Used at init time and for runtime BIOS support, which requires polling
+ * the regs for updates (as a result of AC->DC transition for example).
+ *
+ * LOCKING:
+ * Caller must hold turbo_status_lock (outside of init)
+ */
+static void update_turbo_limits(struct ips_driver *ips)
+{
+	u32 hts = thm_readl(THM_HTS);
+
+	ips->cpu_turbo_enabled = !(hts & HTS_PCTD_DIS);
+	ips->gpu_turbo_enabled = !(hts & HTS_GTD_DIS);
+	ips->core_power_limit = thm_readw(THM_MPCPC);
+	ips->mch_power_limit = thm_readw(THM_MMGPC);
+	ips->mcp_temp_limit = thm_readw(THM_PTL);
+	ips->mcp_power_limit = thm_readw(THM_MPPC);
+
+	/* Ignore BIOS CPU vs GPU pref */
+}
+
+/**
+ * ips_adjust - adjust power clamp based on thermal state
+ * @data: ips driver structure
+ *
+ * Wake up every 5s or so and check whether we should adjust the power clamp.
+ * Check CPU and GPU load to determine which needs adjustment.  There are
+ * several things to consider here:
+ *   - do we need to adjust up or down?
+ *   - is CPU busy?
+ *   - is GPU busy?
+ *   - is CPU in turbo?
+ *   - is GPU in turbo?
+ *   - is CPU or GPU preferred? (CPU is default)
+ *
+ * So, given the above, we do the following:
+ *   - up (TDP available)
+ *     - CPU not busy, GPU not busy - nothing
+ *     - CPU busy, GPU not busy - adjust CPU up
+ *     - CPU not busy, GPU busy - adjust GPU up
+ *     - CPU busy, GPU busy - adjust preferred unit up, taking headroom from
+ *       non-preferred unit if necessary
+ *   - down (at TDP limit)
+ *     - adjust both CPU and GPU down if possible
+ *
+		cpu+ gpu+	cpu+gpu-	cpu-gpu+	cpu-gpu-
+cpu < gpu <	cpu+gpu+	cpu+		gpu+		nothing
+cpu < gpu >=	cpu+gpu-(mcp<)	cpu+gpu-(mcp<)	gpu-		gpu-
+cpu >= gpu <	cpu-gpu+(mcp<)	cpu-		cpu-gpu+(mcp<)	cpu-
+cpu >= gpu >=	cpu-gpu-	cpu-gpu-	cpu-gpu-	cpu-gpu-
+ *
+ */
+static int ips_adjust(void *data)
+{
+	struct ips_driver *ips = data;
+	unsigned long flags;
+
+	dev_dbg(&ips->dev->dev, "starting ips-adjust thread\n");
+
+	/*
+	 * Adjust CPU and GPU clamps every 5s if needed.  Doing it more
+	 * often isn't recommended due to ME interaction.
+	 */
+	do {
+		bool cpu_busy = ips_cpu_busy(ips);
+		bool gpu_busy = ips_gpu_busy(ips);
+
+		spin_lock_irqsave(&ips->turbo_status_lock, flags);
+		if (ips->poll_turbo_status)
+			update_turbo_limits(ips);
+		spin_unlock_irqrestore(&ips->turbo_status_lock, flags);
+
+		/* Update turbo status if necessary */
+		if (ips->cpu_turbo_enabled)
+			ips_enable_cpu_turbo(ips);
+		else
+			ips_disable_cpu_turbo(ips);
+
+		if (ips->gpu_turbo_enabled)
+			ips_enable_gpu_turbo(ips);
+		else
+			ips_disable_gpu_turbo(ips);
+
+		/* We're outside our comfort zone, crank them down */
+		if (!mcp_exceeded(ips)) {
+			ips_cpu_lower(ips);
+			ips_gpu_lower(ips);
+			goto sleep;
+		}
+
+		if (!cpu_exceeded(ips, 0) && cpu_busy)
+			ips_cpu_raise(ips);
+		else
+			ips_cpu_lower(ips);
+
+		if (!mch_exceeded(ips) && gpu_busy)
+			ips_gpu_raise(ips);
+		else
+			ips_gpu_lower(ips);
+
+sleep:
+		schedule_timeout_interruptible(msecs_to_jiffies(IPS_ADJUST_PERIOD));
+	} while (!kthread_should_stop());
+
+	dev_dbg(&ips->dev->dev, "ips-adjust thread stopped\n");
+
+	return 0;
+}
+
+/*
+ * Helpers for reading out temp/power values and calculating their
+ * averages for the decision making and monitoring functions.
+ */
+
+static u16 calc_avg_temp(struct ips_driver *ips, u16 *array)
+{
+	u64 total = 0;
+	int i;
+	u16 avg;
+
+	for (i = 0; i < IPS_SAMPLE_COUNT; i++)
+		total += (u64)(array[i] * 100);
+
+	do_div(total, IPS_SAMPLE_COUNT);
+
+	avg = (u16)total;
+
+	return avg;
+}
+
+static u16 read_mgtv(struct ips_driver *ips)
+{
+	u16 ret;
+	u64 slope, offset;
+	u64 val;
+
+	val = thm_readq(THM_MGTV);
+	val = (val & TV_MASK) >> TV_SHIFT;
+
+	slope = offset = thm_readw(THM_MGTA);
+	slope = (slope & MGTA_SLOPE_MASK) >> MGTA_SLOPE_SHIFT;
+	offset = offset & MGTA_OFFSET_MASK;
+
+	ret = ((val * slope + 0x40) >> 7) + offset;
+
+
+	return ret;
+}
+
+static u16 read_ptv(struct ips_driver *ips)
+{
+	u16 val, slope, offset;
+
+	slope = (ips->pta_val & PTA_SLOPE_MASK) >> PTA_SLOPE_SHIFT;
+	offset = ips->pta_val & PTA_OFFSET_MASK;
+
+	val = thm_readw(THM_PTV) & PTV_MASK;
+
+	return val;
+}
+
+static u16 read_ctv(struct ips_driver *ips, int cpu)
+{
+	int reg = cpu ? THM_CTV2 : THM_CTV1;
+	u16 val;
+
+	val = thm_readw(reg);
+	if (!(val & CTV_TEMP_ERROR))
+		val = (val) >> 6; /* discard fractional component */
+	else
+		val = 0;
+
+	return val;
+}
+
+static u32 get_cpu_power(struct ips_driver *ips, u32 *last, int period)
+{
+	u32 val;
+	u32 ret;
+
+	/*
+	 * CEC is in joules/65535.  Take difference over time to
+	 * get watts.
+	 */
+	val = thm_readl(THM_CEC);
+
+	/* period is in ms and we want mW */
+	ret = (((val - *last) * 1000) / period);
+	ret = (ret * 1000) / 65535;
+	*last = val;
+
+	return ret;
+}
+
+static const u16 temp_decay_factor = 2;
+static u16 update_average_temp(u16 avg, u16 val)
+{
+	u16 ret;
+
+	/* Multiply by 100 for extra precision */
+	ret = (val * 100 / temp_decay_factor) +
+		(((temp_decay_factor - 1) * avg) / temp_decay_factor);
+	return ret;
+}
+
+static const u16 power_decay_factor = 2;
+static u16 update_average_power(u32 avg, u32 val)
+{
+	u32 ret;
+
+	ret = (val / power_decay_factor) +
+		(((power_decay_factor - 1) * avg) / power_decay_factor);
+
+	return ret;
+}
+
+static u32 calc_avg_power(struct ips_driver *ips, u32 *array)
+{
+	u64 total = 0;
+	u32 avg;
+	int i;
+
+	for (i = 0; i < IPS_SAMPLE_COUNT; i++)
+		total += array[i];
+
+	do_div(total, IPS_SAMPLE_COUNT);
+	avg = (u32)total;
+
+	return avg;
+}
+
+static void monitor_timeout(unsigned long arg)
+{
+	wake_up_process((struct task_struct *)arg);
+}
+
+/**
+ * ips_monitor - temp/power monitoring thread
+ * @data: ips driver structure
+ *
+ * This is the main function for the IPS driver.  It monitors power and
+ * tempurature in the MCP and adjusts CPU and GPU power clams accordingly.
+ *
+ * We keep a 5s moving average of power consumption and tempurature.  Using
+ * that data, along with CPU vs GPU preference, we adjust the power clamps
+ * up or down.
+ */
+static int ips_monitor(void *data)
+{
+	struct ips_driver *ips = data;
+	struct timer_list timer;
+	unsigned long seqno_timestamp, expire, last_msecs, last_sample_period;
+	int i;
+	u32 *cpu_samples = NULL, *mchp_samples = NULL, old_cpu_power;
+	u16 *mcp_samples = NULL, *ctv1_samples = NULL, *ctv2_samples = NULL,
+		*mch_samples = NULL;
+	u8 cur_seqno, last_seqno;
+
+	mcp_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
+	ctv1_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
+	ctv2_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
+	mch_samples = kzalloc(sizeof(u16) * IPS_SAMPLE_COUNT, GFP_KERNEL);
+	cpu_samples = kzalloc(sizeof(u32) * IPS_SAMPLE_COUNT, GFP_KERNEL);
+	mchp_samples = kzalloc(sizeof(u32) * IPS_SAMPLE_COUNT, GFP_KERNEL);
+	if (!mcp_samples || !ctv1_samples || !ctv2_samples || !mch_samples) {
+		dev_err(&ips->dev->dev,
+			"failed to allocate sample array, ips disabled\n");
+		kfree(mcp_samples);
+		kfree(ctv1_samples);
+		kfree(ctv2_samples);
+		kfree(mch_samples);
+		kfree(cpu_samples);
+		kthread_stop(ips->adjust);
+		return -ENOMEM;
+	}
+
+	last_seqno = (thm_readl(THM_ITV) & ITV_ME_SEQNO_MASK) >>
+		ITV_ME_SEQNO_SHIFT;
+	seqno_timestamp = get_jiffies_64();
+
+	old_cpu_power = thm_readl(THM_CEC) / 65535;
+	schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));
+
+	/* Collect an initial average */
+	for (i = 0; i < IPS_SAMPLE_COUNT; i++) {
+		u32 mchp, cpu_power;
+		u16 val;
+
+		mcp_samples[i] = read_ptv(ips);
+
+		val = read_ctv(ips, 0);
+		ctv1_samples[i] = val;
+
+		val = read_ctv(ips, 1);
+		ctv2_samples[i] = val;
+
+		val = read_mgtv(ips);
+		mch_samples[i] = val;
+
+		cpu_power = get_cpu_power(ips, &old_cpu_power,
+					  IPS_SAMPLE_PERIOD);
+		cpu_samples[i] = cpu_power;
+
+		if (ips->read_mch_val) {
+			mchp = ips->read_mch_val();
+			mchp_samples[i] = mchp;
+		}
+
+		schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));
+		if (kthread_should_stop())
+			break;
+	}
+
+	ips->mcp_avg_temp = calc_avg_temp(ips, mcp_samples);
+	ips->ctv1_avg_temp = calc_avg_temp(ips, ctv1_samples);
+	ips->ctv2_avg_temp = calc_avg_temp(ips, ctv2_samples);
+	ips->mch_avg_temp = calc_avg_temp(ips, mch_samples);
+	ips->cpu_avg_power = calc_avg_power(ips, cpu_samples);
+	ips->mch_avg_power = calc_avg_power(ips, mchp_samples);
+	kfree(mcp_samples);
+	kfree(ctv1_samples);
+	kfree(ctv2_samples);
+	kfree(mch_samples);
+	kfree(cpu_samples);
+	kfree(mchp_samples);
+
+	/* Start the adjustment thread now that we have data */
+	wake_up_process(ips->adjust);
+
+	/*
+	 * Ok, now we have an initial avg.  From here on out, we track the
+	 * running avg using a decaying average calculation.  This allows
+	 * us to reduce the sample frequency if the CPU and GPU are idle.
+	 */
+	old_cpu_power = thm_readl(THM_CEC);
+	schedule_timeout_interruptible(msecs_to_jiffies(IPS_SAMPLE_PERIOD));
+	last_sample_period = IPS_SAMPLE_PERIOD;
+
+	setup_deferrable_timer_on_stack(&timer, monitor_timeout,
+					(unsigned long)current);
+	do {
+		u32 cpu_val, mch_val;
+		u16 val;
+
+		/* MCP itself */
+		val = read_ptv(ips);
+		ips->mcp_avg_temp = update_average_temp(ips->mcp_avg_temp, val);
+
+		/* Processor 0 */
+		val = read_ctv(ips, 0);
+		ips->ctv1_avg_temp =
+			update_average_temp(ips->ctv1_avg_temp, val);
+		/* Power */
+		cpu_val = get_cpu_power(ips, &old_cpu_power,
+					last_sample_period);
+		ips->cpu_avg_power =
+			update_average_power(ips->cpu_avg_power, cpu_val);
+
+		if (ips->second_cpu) {
+			/* Processor 1 */
+			val = read_ctv(ips, 1);
+			ips->ctv2_avg_temp =
+				update_average_temp(ips->ctv2_avg_temp, val);
+		}
+
+		/* MCH */
+		val = read_mgtv(ips);
+		ips->mch_avg_temp = update_average_temp(ips->mch_avg_temp, val);
+		/* Power */
+		if (ips->read_mch_val) {
+			mch_val = ips->read_mch_val();
+			ips->mch_avg_power =
+				update_average_power(ips->mch_avg_power,
+						     mch_val);
+		}
+
+		/*
+		 * Make sure ME is updating thermal regs.
+		 * Note:
+		 * If it's been more than a second since the last update,
+		 * the ME is probably hung.
+		 */
+		cur_seqno = (thm_readl(THM_ITV) & ITV_ME_SEQNO_MASK) >>
+			ITV_ME_SEQNO_SHIFT;
+		if (cur_seqno == last_seqno &&
+		    time_after(jiffies, seqno_timestamp + HZ)) {
+			dev_warn(&ips->dev->dev, "ME failed to update for more than 1s, likely hung\n");
+		} else {
+			seqno_timestamp = get_jiffies_64();
+			last_seqno = cur_seqno;
+		}
+
+		last_msecs = jiffies_to_msecs(jiffies);
+		expire = jiffies + msecs_to_jiffies(IPS_SAMPLE_PERIOD);
+
+		__set_current_state(TASK_UNINTERRUPTIBLE);
+		mod_timer(&timer, expire);
+		schedule();
+
+		/* Calculate actual sample period for power averaging */
+		last_sample_period = jiffies_to_msecs(jiffies) - last_msecs;
+		if (!last_sample_period)
+			last_sample_period = 1;
+	} while (!kthread_should_stop());
+
+	del_timer_sync(&timer);
+	destroy_timer_on_stack(&timer);
+
+	dev_dbg(&ips->dev->dev, "ips-monitor thread stopped\n");
+
+	return 0;
+}
+
+#if 0
+#define THM_DUMPW(reg) \
+	{ \
+	u16 val = thm_readw(reg); \
+	dev_dbg(&ips->dev->dev, #reg ": 0x%04x\n", val); \
+	}
+#define THM_DUMPL(reg) \
+	{ \
+	u32 val = thm_readl(reg); \
+	dev_dbg(&ips->dev->dev, #reg ": 0x%08x\n", val); \
+	}
+#define THM_DUMPQ(reg) \
+	{ \
+	u64 val = thm_readq(reg); \
+	dev_dbg(&ips->dev->dev, #reg ": 0x%016x\n", val); \
+	}
+
+static void dump_thermal_info(struct ips_driver *ips)
+{
+	u16 ptl;
+
+	ptl = thm_readw(THM_PTL);
+	dev_dbg(&ips->dev->dev, "Processor temp limit: %d\n", ptl);
+
+	THM_DUMPW(THM_CTA);
+	THM_DUMPW(THM_TRC);
+	THM_DUMPW(THM_CTV1);
+	THM_DUMPL(THM_STS);
+	THM_DUMPW(THM_PTV);
+	THM_DUMPQ(THM_MGTV);
+}
+#endif
+
+/**
+ * ips_irq_handler - handle temperature triggers and other IPS events
+ * @irq: irq number
+ * @arg: unused
+ *
+ * Handle temperature limit trigger events, generally by lowering the clamps.
+ * If we're at a critical limit, we clamp back to the lowest possible value
+ * to prevent emergency shutdown.
+ */
+static irqreturn_t ips_irq_handler(int irq, void *arg)
+{
+	struct ips_driver *ips = arg;
+	u8 tses = thm_readb(THM_TSES);
+	u8 tes = thm_readb(THM_TES);
+
+	if (!tses && !tes)
+		return IRQ_NONE;
+
+	dev_info(&ips->dev->dev, "TSES: 0x%02x\n", tses);
+	dev_info(&ips->dev->dev, "TES: 0x%02x\n", tes);
+
+	/* STS update from EC? */
+	if (tes & 1) {
+		u32 sts, tc1;
+
+		sts = thm_readl(THM_STS);
+		tc1 = thm_readl(THM_TC1);
+
+		if (sts & STS_NVV) {
+			spin_lock(&ips->turbo_status_lock);
+			ips->core_power_limit = (sts & STS_PCPL_MASK) >>
+				STS_PCPL_SHIFT;
+			ips->mch_power_limit = (sts & STS_GPL_MASK) >>
+				STS_GPL_SHIFT;
+			/* ignore EC CPU vs GPU pref */
+			ips->cpu_turbo_enabled = !(sts & STS_PCTD_DIS);
+			ips->gpu_turbo_enabled = !(sts & STS_GTD_DIS);
+			ips->mcp_temp_limit = (sts & STS_PTL_MASK) >>
+				STS_PTL_SHIFT;
+			ips->mcp_power_limit = (tc1 & STS_PPL_MASK) >>
+				STS_PPL_SHIFT;
+			spin_unlock(&ips->turbo_status_lock);
+
+			thm_writeb(THM_SEC, SEC_ACK);
+		}
+		thm_writeb(THM_TES, tes);
+	}
+
+	/* Thermal trip */
+	if (tses) {
+		dev_warn(&ips->dev->dev,
+			 "thermal trip occurred, tses: 0x%04x\n", tses);
+		thm_writeb(THM_TSES, tses);
+	}
+
+	return IRQ_HANDLED;
+}
+
+#ifndef CONFIG_DEBUG_FS
+static void ips_debugfs_init(struct ips_driver *ips) { return; }
+static void ips_debugfs_cleanup(struct ips_driver *ips) { return; }
+#else
+
+/* Expose current state and limits in debugfs if possible */
+
+struct ips_debugfs_node {
+	struct ips_driver *ips;
+	char *name;
+	int (*show)(struct seq_file *m, void *data);
+};
+
+static int show_cpu_temp(struct seq_file *m, void *data)
+{
+	struct ips_driver *ips = m->private;
+
+	seq_printf(m, "%d.%02d\n", ips->ctv1_avg_temp / 100,
+		   ips->ctv1_avg_temp % 100);
+
+	return 0;
+}
+
+static int show_cpu_power(struct seq_file *m, void *data)
+{
+	struct ips_driver *ips = m->private;
+
+	seq_printf(m, "%dmW\n", ips->cpu_avg_power);
+
+	return 0;
+}
+
+static int show_cpu_clamp(struct seq_file *m, void *data)
+{
+	u64 turbo_override;
+	int tdp, tdc;
+
+	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+
+	tdp = (int)(turbo_override & TURBO_TDP_MASK);
+	tdc = (int)((turbo_override & TURBO_TDC_MASK) >> TURBO_TDC_SHIFT);
+
+	/* Convert to .1W/A units */
+	tdp = tdp * 10 / 8;
+	tdc = tdc * 10 / 8;
+
+	/* Watts Amperes */
+	seq_printf(m, "%d.%dW %d.%dA\n", tdp / 10, tdp % 10,
+		   tdc / 10, tdc % 10);
+
+	return 0;
+}
+
+static int show_mch_temp(struct seq_file *m, void *data)
+{
+	struct ips_driver *ips = m->private;
+
+	seq_printf(m, "%d.%02d\n", ips->mch_avg_temp / 100,
+		   ips->mch_avg_temp % 100);
+
+	return 0;
+}
+
+static int show_mch_power(struct seq_file *m, void *data)
+{
+	struct ips_driver *ips = m->private;
+
+	seq_printf(m, "%dmW\n", ips->mch_avg_power);
+
+	return 0;
+}
+
+static struct ips_debugfs_node ips_debug_files[] = {
+	{ NULL, "cpu_temp", show_cpu_temp },
+	{ NULL, "cpu_power", show_cpu_power },
+	{ NULL, "cpu_clamp", show_cpu_clamp },
+	{ NULL, "mch_temp", show_mch_temp },
+	{ NULL, "mch_power", show_mch_power },
+};
+
+static int ips_debugfs_open(struct inode *inode, struct file *file)
+{
+	struct ips_debugfs_node *node = inode->i_private;
+
+	return single_open(file, node->show, node->ips);
+}
+
+static const struct file_operations ips_debugfs_ops = {
+	.owner = THIS_MODULE,
+	.open = ips_debugfs_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static void ips_debugfs_cleanup(struct ips_driver *ips)
+{
+	if (ips->debug_root)
+		debugfs_remove_recursive(ips->debug_root);
+	return;
+}
+
+static void ips_debugfs_init(struct ips_driver *ips)
+{
+	int i;
+
+	ips->debug_root = debugfs_create_dir("ips", NULL);
+	if (!ips->debug_root) {
+		dev_err(&ips->dev->dev,
+			"failed to create debugfs entries: %ld\n",
+			PTR_ERR(ips->debug_root));
+		return;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(ips_debug_files); i++) {
+		struct dentry *ent;
+		struct ips_debugfs_node *node = &ips_debug_files[i];
+
+		node->ips = ips;
+		ent = debugfs_create_file(node->name, S_IFREG | S_IRUGO,
+					  ips->debug_root, node,
+					  &ips_debugfs_ops);
+		if (!ent) {
+			dev_err(&ips->dev->dev,
+				"failed to create debug file: %ld\n",
+				PTR_ERR(ent));
+			goto err_cleanup;
+		}
+	}
+
+	return;
+
+err_cleanup:
+	ips_debugfs_cleanup(ips);
+	return;
+}
+#endif /* CONFIG_DEBUG_FS */
+
+/**
+ * ips_detect_cpu - detect whether CPU supports IPS
+ *
+ * Walk our list and see if we're on a supported CPU.  If we find one,
+ * return the limits for it.
+ */
+static struct ips_mcp_limits *ips_detect_cpu(struct ips_driver *ips)
+{
+	u64 turbo_power, misc_en;
+	struct ips_mcp_limits *limits = NULL;
+	u16 tdp;
+
+	if (!(boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 37)) {
+		dev_info(&ips->dev->dev, "Non-IPS CPU detected.\n");
+		goto out;
+	}
+
+	rdmsrl(IA32_MISC_ENABLE, misc_en);
+	/*
+	 * If the turbo enable bit isn't set, we shouldn't try to enable/disable
+	 * turbo manually or we'll get an illegal MSR access, even though
+	 * turbo will still be available.
+	 */
+	if (!(misc_en & IA32_MISC_TURBO_EN))
+		; /* add turbo MSR write allowed flag if necessary */
+
+	if (strstr(boot_cpu_data.x86_model_id, "CPU       M"))
+		limits = &ips_sv_limits;
+	else if (strstr(boot_cpu_data.x86_model_id, "CPU       L"))
+		limits = &ips_lv_limits;
+	else if (strstr(boot_cpu_data.x86_model_id, "CPU       U"))
+		limits = &ips_ulv_limits;
+	else
+		dev_info(&ips->dev->dev, "No CPUID match found.\n");
+
+	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_power);
+	tdp = turbo_power & TURBO_TDP_MASK;
+
+	/* Sanity check TDP against CPU */
+	if (limits->mcp_power_limit != (tdp / 8) * 1000) {
+		dev_warn(&ips->dev->dev, "Warning: CPU TDP doesn't match expected value (found %d, expected %d)\n",
+			 tdp / 8, limits->mcp_power_limit / 1000);
+	}
+
+out:
+	return limits;
+}
+
+/**
+ * ips_get_i915_syms - try to get GPU control methods from i915 driver
+ * @ips: IPS driver
+ *
+ * The i915 driver exports several interfaces to allow the IPS driver to
+ * monitor and control graphics turbo mode.  If we can find them, we can
+ * enable graphics turbo, otherwise we must disable it to avoid exceeding
+ * thermal and power limits in the MCP.
+ */
+static bool ips_get_i915_syms(struct ips_driver *ips)
+{
+	ips->read_mch_val = symbol_get(i915_read_mch_val);
+	if (!ips->read_mch_val)
+		goto out_err;
+	ips->gpu_raise = symbol_get(i915_gpu_raise);
+	if (!ips->gpu_raise)
+		goto out_put_mch;
+	ips->gpu_lower = symbol_get(i915_gpu_lower);
+	if (!ips->gpu_lower)
+		goto out_put_raise;
+	ips->gpu_busy = symbol_get(i915_gpu_busy);
+	if (!ips->gpu_busy)
+		goto out_put_lower;
+	ips->gpu_turbo_disable = symbol_get(i915_gpu_turbo_disable);
+	if (!ips->gpu_turbo_disable)
+		goto out_put_busy;
+
+	return true;
+
+out_put_busy:
+	symbol_put(i915_gpu_turbo_disable);
+out_put_lower:
+	symbol_put(i915_gpu_lower);
+out_put_raise:
+	symbol_put(i915_gpu_raise);
+out_put_mch:
+	symbol_put(i915_read_mch_val);
+out_err:
+	return false;
+}
+
+static DEFINE_PCI_DEVICE_TABLE(ips_id_table) = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL,
+		     PCI_DEVICE_ID_INTEL_THERMAL_SENSOR), },
+	{ 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, ips_id_table);
+
+static int ips_probe(struct pci_dev *dev, const struct pci_device_id *id)
+{
+	u64 platform_info;
+	struct ips_driver *ips;
+	u32 hts;
+	int ret = 0;
+	u16 htshi, trc, trc_required_mask;
+	u8 tse;
+
+	ips = kzalloc(sizeof(struct ips_driver), GFP_KERNEL);
+	if (!ips)
+		return -ENOMEM;
+
+	pci_set_drvdata(dev, ips);
+	ips->dev = dev;
+
+	ips->limits = ips_detect_cpu(ips);
+	if (!ips->limits) {
+		dev_info(&dev->dev, "IPS not supported on this CPU\n");
+		ret = -ENXIO;
+		goto error_free;
+	}
+
+	spin_lock_init(&ips->turbo_status_lock);
+
+	if (!pci_resource_start(dev, 0)) {
+		dev_err(&dev->dev, "TBAR not assigned, aborting\n");
+		ret = -ENXIO;
+		goto error_free;
+	}
+
+	ret = pci_request_regions(dev, "ips thermal sensor");
+	if (ret) {
+		dev_err(&dev->dev, "thermal resource busy, aborting\n");
+		goto error_free;
+	}
+
+	ret = pci_enable_device(dev);
+	if (ret) {
+		dev_err(&dev->dev, "can't enable PCI device, aborting\n");
+		goto error_free;
+	}
+
+	ips->regmap = ioremap(pci_resource_start(dev, 0),
+			      pci_resource_len(dev, 0));
+	if (!ips->regmap) {
+		dev_err(&dev->dev, "failed to map thermal regs, aborting\n");
+		ret = -EBUSY;
+		goto error_release;
+	}
+
+	tse = thm_readb(THM_TSE);
+	if (tse != TSE_EN) {
+		dev_err(&dev->dev, "thermal device not enabled (0x%02x), aborting\n", tse);
+		ret = -ENXIO;
+		goto error_unmap;
+	}
+
+	trc = thm_readw(THM_TRC);
+	trc_required_mask = TRC_CORE1_EN | TRC_CORE_PWR | TRC_MCH_EN;
+	if ((trc & trc_required_mask) != trc_required_mask) {
+		dev_err(&dev->dev, "thermal reporting for required devices not enabled, aborting\n");
+		ret = -ENXIO;
+		goto error_unmap;
+	}
+
+	if (trc & TRC_CORE2_EN)
+		ips->second_cpu = true;
+
+	if (!ips_get_i915_syms(ips)) {
+		dev_err(&dev->dev, "failed to get i915 symbols, graphics turbo disabled\n");
+		ips->gpu_turbo_enabled = false;
+	} else {
+		dev_dbg(&dev->dev, "graphics turbo enabled\n");
+		ips->gpu_turbo_enabled = true;
+	}
+
+	update_turbo_limits(ips);
+	dev_dbg(&dev->dev, "max cpu power clamp: %dW\n",
+		ips->mcp_power_limit / 10);
+	dev_dbg(&dev->dev, "max core power clamp: %dW\n",
+		ips->core_power_limit / 10);
+	/* BIOS may update limits at runtime */
+	if (thm_readl(THM_PSC) & PSP_PBRT)
+		ips->poll_turbo_status = true;
+
+	/*
+	 * Check PLATFORM_INFO MSR to make sure this chip is
+	 * turbo capable.
+	 */
+	rdmsrl(PLATFORM_INFO, platform_info);
+	if (!(platform_info & PLATFORM_TDP)) {
+		dev_err(&dev->dev, "platform indicates TDP override unavailable, aborting\n");
+		ret = -ENODEV;
+		goto error_unmap;
+	}
+
+	/*
+	 * IRQ handler for ME interaction
+	 * Note: don't use MSI here as the PCH has bugs.
+	 */
+	pci_disable_msi(dev);
+	ret = request_irq(dev->irq, ips_irq_handler, IRQF_SHARED, "ips",
+			  ips);
+	if (ret) {
+		dev_err(&dev->dev, "request irq failed, aborting\n");
+		goto error_unmap;
+	}
+
+	/* Enable aux, hot & critical interrupts */
+	thm_writeb(THM_TSPIEN, TSPIEN_AUX2_LOHI | TSPIEN_CRIT_LOHI |
+		   TSPIEN_HOT_LOHI | TSPIEN_AUX_LOHI);
+	thm_writeb(THM_TEN, TEN_UPDATE_EN);
+
+	/* Collect adjustment values */
+	ips->cta_val = thm_readw(THM_CTA);
+	ips->pta_val = thm_readw(THM_PTA);
+	ips->mgta_val = thm_readw(THM_MGTA);
+
+	/* Save turbo limits & ratios */
+	rdmsrl(TURBO_POWER_CURRENT_LIMIT, ips->orig_turbo_limit);
+
+	ips_enable_cpu_turbo(ips);
+	ips->cpu_turbo_enabled = true;
+
+	/* Set up the work queue and monitor/adjust threads */
+	ips->monitor = kthread_run(ips_monitor, ips, "ips-monitor");
+	if (IS_ERR(ips->monitor)) {
+		dev_err(&dev->dev,
+			"failed to create thermal monitor thread, aborting\n");
+		ret = -ENOMEM;
+		goto error_free_irq;
+	}
+
+	ips->adjust = kthread_create(ips_adjust, ips, "ips-adjust");
+	if (IS_ERR(ips->adjust)) {
+		dev_err(&dev->dev,
+			"failed to create thermal adjust thread, aborting\n");
+		ret = -ENOMEM;
+		goto error_thread_cleanup;
+	}
+
+	hts = (ips->core_power_limit << HTS_PCPL_SHIFT) |
+		(ips->mcp_temp_limit << HTS_PTL_SHIFT) | HTS_NVV;
+	htshi = HTS2_PRST_RUNNING << HTS2_PRST_SHIFT;
+
+	thm_writew(THM_HTSHI, htshi);
+	thm_writel(THM_HTS, hts);
+
+	ips_debugfs_init(ips);
+
+	dev_info(&dev->dev, "IPS driver initialized, MCP temp limit %d\n",
+		 ips->mcp_temp_limit);
+	return ret;
+
+error_thread_cleanup:
+	kthread_stop(ips->monitor);
+error_free_irq:
+	free_irq(ips->dev->irq, ips);
+error_unmap:
+	iounmap(ips->regmap);
+error_release:
+	pci_release_regions(dev);
+error_free:
+	kfree(ips);
+	return ret;
+}
+
+static void ips_remove(struct pci_dev *dev)
+{
+	struct ips_driver *ips = pci_get_drvdata(dev);
+	u64 turbo_override;
+
+	if (!ips)
+		return;
+
+	ips_debugfs_cleanup(ips);
+
+	/* Release i915 driver */
+	if (ips->read_mch_val)
+		symbol_put(i915_read_mch_val);
+	if (ips->gpu_raise)
+		symbol_put(i915_gpu_raise);
+	if (ips->gpu_lower)
+		symbol_put(i915_gpu_lower);
+	if (ips->gpu_busy)
+		symbol_put(i915_gpu_busy);
+	if (ips->gpu_turbo_disable)
+		symbol_put(i915_gpu_turbo_disable);
+
+	rdmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+	turbo_override &= ~(TURBO_TDC_OVR_EN | TURBO_TDP_OVR_EN);
+	wrmsrl(TURBO_POWER_CURRENT_LIMIT, turbo_override);
+	wrmsrl(TURBO_POWER_CURRENT_LIMIT, ips->orig_turbo_limit);
+
+	free_irq(ips->dev->irq, ips);
+	if (ips->adjust)
+		kthread_stop(ips->adjust);
+	if (ips->monitor)
+		kthread_stop(ips->monitor);
+	iounmap(ips->regmap);
+	pci_release_regions(dev);
+	kfree(ips);
+	dev_dbg(&dev->dev, "IPS driver removed\n");
+}
+
+#ifdef CONFIG_PM
+static int ips_suspend(struct pci_dev *dev, pm_message_t state)
+{
+	return 0;
+}
+
+static int ips_resume(struct pci_dev *dev)
+{
+	return 0;
+}
+#else
+#define ips_suspend NULL
+#define ips_resume NULL
+#endif /* CONFIG_PM */
+
+static void ips_shutdown(struct pci_dev *dev)
+{
+}
+
+static struct pci_driver ips_pci_driver = {
+	.name = "intel ips",
+	.id_table = ips_id_table,
+	.probe = ips_probe,
+	.remove = ips_remove,
+	.suspend = ips_suspend,
+	.resume = ips_resume,
+	.shutdown = ips_shutdown,
+};
+
+static int __init ips_init(void)
+{
+	return pci_register_driver(&ips_pci_driver);
+}
+module_init(ips_init);
+
+static void ips_exit(void)
+{
+	pci_unregister_driver(&ips_pci_driver);
+	return;
+}
+module_exit(ips_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jesse Barnes <jbarnes@virtuousgeek.org>");
+MODULE_DESCRIPTION("Intelligent Power Sharing Driver");
diff --git a/include/drm/i915_drm.h b/include/drm/i915_drm.h
index b64a8d7..6cf72a8 100644
--- a/include/drm/i915_drm.h
+++ b/include/drm/i915_drm.h
@@ -33,6 +33,15 @@ 
  * subject to backwards-compatibility constraints.
  */
 
+#ifdef __KERNEL__
+/* For use by IPS driver */
+extern unsigned long i915_read_mch_val(void);
+extern bool i915_gpu_raise(void);
+extern bool i915_gpu_lower(void);
+extern bool i915_gpu_busy(void);
+extern bool i915_gpu_turbo_disable(void);
+#endif
+
 /* Each region is a minimum of 16k, and there are at most 255 of them.
  */
 #define I915_NR_TEX_REGIONS 255	/* table size 2k - maximum due to use