1 files changed, 201 insertions, 73 deletions

diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index a3df9c039bd4..f0cce3c2dc3a 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -29,6 +29,7 @@
 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/delay.h>
 
 #include <asm/msr.h>
 #include <asm/timex.h>
@@ -55,7 +56,6 @@
 /* Flags */
 #define USE_ACPI_C3		(1 << 1)
 #define USE_NORTHBRIDGE		(1 << 2)
-#define USE_VT8235		(1 << 3)
 
 static int cpu_model;
 static unsigned int numscales=16;
@@ -63,22 +63,20 @@ static unsigned int fsb;
 
 static const struct mV_pos *vrm_mV_table;
 static const unsigned char *mV_vrm_table;
-struct f_msr {
-	u8 vrm;
-	u8 pos;
-};
-static struct f_msr f_msr_table[32];
 
 static unsigned int highest_speed, lowest_speed; /* kHz */
 static unsigned int minmult, maxmult;
 static int can_scale_voltage;
 static struct acpi_processor *pr = NULL;
 static struct acpi_processor_cx *cx = NULL;
+static u32 acpi_regs_addr;
 static u8 longhaul_flags;
-static u8 longhaul_pos;
+static unsigned int longhaul_index;
 
 /* Module parameters */
 static int scale_voltage;
+static int disable_acpi_c3;
+static int revid_errata;
 
 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "longhaul", msg)
 
@@ -144,7 +142,7 @@ static void do_longhaul1(unsigned int clock_ratio_index)
 	rdmsrl(MSR_VIA_BCR2, bcr2.val);
 	/* Enable software clock multiplier */
 	bcr2.bits.ESOFTBF = 1;
-	bcr2.bits.CLOCKMUL = clock_ratio_index;
+	bcr2.bits.CLOCKMUL = clock_ratio_index & 0xff;
 
 	/* Sync to timer tick */
 	safe_halt();
@@ -163,26 +161,27 @@ static void do_longhaul1(unsigned int clock_ratio_index)
 
 /* For processor with Longhaul MSR */
 
-static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
+static void do_powersaver(int cx_address, unsigned int clock_ratio_index,
+			  unsigned int dir)
 {
 	union msr_longhaul longhaul;
-	u8 dest_pos;
 	u32 t;
 
-	dest_pos = f_msr_table[clock_ratio_index].pos;
-
 	rdmsrl(MSR_VIA_LONGHAUL, longhaul.val);
 	/* Setup new frequency */
-	longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+	if (!revid_errata)
+		longhaul.bits.RevisionKey = longhaul.bits.RevisionID;
+	else
+		longhaul.bits.RevisionKey = 0;
 	longhaul.bits.SoftBusRatio = clock_ratio_index & 0xf;
 	longhaul.bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
 	/* Setup new voltage */
 	if (can_scale_voltage)
-		longhaul.bits.SoftVID = f_msr_table[clock_ratio_index].vrm;
+		longhaul.bits.SoftVID = (clock_ratio_index >> 8) & 0x1f;
 	/* Sync to timer tick */
 	safe_halt();
 	/* Raise voltage if necessary */
-	if (can_scale_voltage && longhaul_pos < dest_pos) {
+	if (can_scale_voltage && dir) {
 		longhaul.bits.EnableSoftVID = 1;
 		wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
 		/* Change voltage */
@@ -199,7 +198,6 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
 		}
 		longhaul.bits.EnableSoftVID = 0;
 		wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
-		longhaul_pos = dest_pos;
 	}
 
 	/* Change frequency on next halt or sleep */
@@ -220,7 +218,7 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
 	wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
 
 	/* Reduce voltage if necessary */
-	if (can_scale_voltage && longhaul_pos > dest_pos) {
+	if (can_scale_voltage && !dir) {
 		longhaul.bits.EnableSoftVID = 1;
 		wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
 		/* Change voltage */
@@ -237,7 +235,6 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
 		}
 		longhaul.bits.EnableSoftVID = 0;
 		wrmsrl(MSR_VIA_LONGHAUL, longhaul.val);
-		longhaul_pos = dest_pos;
 	}
 }
 
@@ -248,25 +245,28 @@ static void do_powersaver(int cx_address, unsigned int clock_ratio_index)
  * Sets a new clock ratio.
  */
 
-static void longhaul_setstate(unsigned int clock_ratio_index)
+static void longhaul_setstate(unsigned int table_index)
 {
+	unsigned int clock_ratio_index;
 	int speed, mult;
 	struct cpufreq_freqs freqs;
-	static unsigned int old_ratio=-1;
 	unsigned long flags;
 	unsigned int pic1_mask, pic2_mask;
+	u16 bm_status = 0;
+	u32 bm_timeout = 1000;
+	unsigned int dir = 0;
 
-	if (old_ratio == clock_ratio_index)
-		return;
-	old_ratio = clock_ratio_index;
-
-	mult = clock_ratio[clock_ratio_index];
+	clock_ratio_index = longhaul_table[table_index].index;
+	/* Safety precautions */
+	mult = clock_ratio[clock_ratio_index & 0x1f];
 	if (mult == -1)
 		return;
-
 	speed = calc_speed(mult);
 	if ((speed > highest_speed) || (speed < lowest_speed))
 		return;
+	/* Voltage transition before frequency transition? */
+	if (can_scale_voltage && longhaul_index < table_index)
+		dir = 1;
 
 	freqs.old = calc_speed(longhaul_get_cpu_mult());
 	freqs.new = speed;
@@ -276,7 +276,7 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
 
 	dprintk ("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n",
 			fsb, mult/10, mult%10, print_speed(speed/1000));
-
+retry_loop:
 	preempt_disable();
 	local_irq_save(flags);
 
@@ -285,11 +285,24 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
 	outb(0xFF,0xA1);	/* Overkill */
 	outb(0xFE,0x21);	/* TMR0 only */
 
+	/* Wait while PCI bus is busy. */
+	if (acpi_regs_addr && (longhaul_flags & USE_NORTHBRIDGE
+	    || ((pr != NULL) && pr->flags.bm_control))) {
+		bm_status = inw(acpi_regs_addr);
+		bm_status &= 1 << 4;
+		while (bm_status && bm_timeout) {
+			outw(1 << 4, acpi_regs_addr);
+			bm_timeout--;
+			bm_status = inw(acpi_regs_addr);
+			bm_status &= 1 << 4;
+		}
+	}
+
 	if (longhaul_flags & USE_NORTHBRIDGE) {
 		/* Disable AGP and PCI arbiters */
 		outb(3, 0x22);
 	} else if ((pr != NULL) && pr->flags.bm_control) {
- 		/* Disable bus master arbitration */
+		/* Disable bus master arbitration */
 		acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
 	}
 	switch (longhaul_version) {
@@ -314,9 +327,9 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
 		if (longhaul_flags & USE_ACPI_C3) {
 			/* Don't allow wakeup */
 			acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0);
-			do_powersaver(cx->address, clock_ratio_index);
+			do_powersaver(cx->address, clock_ratio_index, dir);
 		} else {
-			do_powersaver(0, clock_ratio_index);
+			do_powersaver(0, clock_ratio_index, dir);
 		}
 		break;
 	}
@@ -335,7 +348,51 @@ static void longhaul_setstate(unsigned int clock_ratio_index)
 	preempt_enable();
 
 	freqs.new = calc_speed(longhaul_get_cpu_mult());
+	/* Check if requested frequency is set. */
+	if (unlikely(freqs.new != speed)) {
+		printk(KERN_INFO PFX "Failed to set requested frequency!\n");
+		/* Revision ID = 1 but processor is expecting revision key
+		 * equal to 0. Jumpers at the bottom of processor will change
+		 * multiplier and FSB, but will not change bits in Longhaul
+		 * MSR nor enable voltage scaling. */
+		if (!revid_errata) {
+			printk(KERN_INFO PFX "Enabling \"Ignore Revision ID\" "
+						"option.\n");
+			revid_errata = 1;
+			msleep(200);
+			goto retry_loop;
+		}
+		/* Why ACPI C3 sometimes doesn't work is a mystery for me.
+		 * But it does happen. Processor is entering ACPI C3 state,
+		 * but it doesn't change frequency. I tried poking various
+		 * bits in northbridge registers, but without success. */
+		if (longhaul_flags & USE_ACPI_C3) {
+			printk(KERN_INFO PFX "Disabling ACPI C3 support.\n");
+			longhaul_flags &= ~USE_ACPI_C3;
+			if (revid_errata) {
+				printk(KERN_INFO PFX "Disabling \"Ignore "
+						"Revision ID\" option.\n");
+				revid_errata = 0;
+			}
+			msleep(200);
+			goto retry_loop;
+		}
+		/* This shouldn't happen. Longhaul ver. 2 was reported not
+		 * working on processors without voltage scaling, but with
+		 * RevID = 1. RevID errata will make things right. Just
+		 * to be 100% sure. */
+		if (longhaul_version == TYPE_LONGHAUL_V2) {
+			printk(KERN_INFO PFX "Switching to Longhaul ver. 1\n");
+			longhaul_version = TYPE_LONGHAUL_V1;
+			msleep(200);
+			goto retry_loop;
+		}
+	}
+	/* Report true CPU frequency */
 	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+	if (!bm_timeout)
+		printk(KERN_INFO PFX "Warning: Timeout while waiting for idle PCI bus.\n");
 }
 
 /*
@@ -369,7 +426,8 @@ static int guess_fsb(int mult)
 
 static int __init longhaul_get_ranges(void)
 {
-	unsigned int j, k = 0;
+	unsigned int i, j, k = 0;
+	unsigned int ratio;
 	int mult;
 
 	/* Get current frequency */
@@ -423,8 +481,7 @@ static int __init longhaul_get_ranges(void)
 	if(!longhaul_table)
 		return -ENOMEM;
 
-	for (j=0; j < numscales; j++) {
-		unsigned int ratio;
+	for (j = 0; j < numscales; j++) {
 		ratio = clock_ratio[j];
 		if (ratio == -1)
 			continue;
@@ -434,13 +491,41 @@ static int __init longhaul_get_ranges(void)
 		longhaul_table[k].index	= j;
 		k++;
 	}
+	if (k <= 1) {
+		kfree(longhaul_table);
+		return -ENODEV;
+	}
+	/* Sort */
+	for (j = 0; j < k - 1; j++) {
+		unsigned int min_f, min_i;
+		min_f = longhaul_table[j].frequency;
+		min_i = j;
+		for (i = j + 1; i < k; i++) {
+			if (longhaul_table[i].frequency < min_f) {
+				min_f = longhaul_table[i].frequency;
+				min_i = i;
+			}
+		}
+		if (min_i != j) {
+			unsigned int temp;
+			temp = longhaul_table[j].frequency;
+			longhaul_table[j].frequency = longhaul_table[min_i].frequency;
+			longhaul_table[min_i].frequency = temp;
+			temp = longhaul_table[j].index;
+			longhaul_table[j].index = longhaul_table[min_i].index;
+			longhaul_table[min_i].index = temp;
+		}
+	}
 
 	longhaul_table[k].frequency = CPUFREQ_TABLE_END;
-	if (!k) {
-		kfree (longhaul_table);
-		return -EINVAL;
-	}
 
+	/* Find index we are running on */
+	for (j = 0; j < k; j++) {
+		if (clock_ratio[longhaul_table[j].index & 0x1f] == mult) {
+			longhaul_index = j;
+			break;
+		}
+	}
 	return 0;
 }
 
@@ -448,7 +533,7 @@ static int __init longhaul_get_ranges(void)
 static void __init longhaul_setup_voltagescaling(void)
 {
 	union msr_longhaul longhaul;
-	struct mV_pos minvid, maxvid;
+	struct mV_pos minvid, maxvid, vid;
 	unsigned int j, speed, pos, kHz_step, numvscales;
 	int min_vid_speed;
 
@@ -459,11 +544,11 @@ static void __init longhaul_setup_voltagescaling(void)
 	}
 
 	if (!longhaul.bits.VRMRev) {
-		printk (KERN_INFO PFX "VRM 8.5\n");
+		printk(KERN_INFO PFX "VRM 8.5\n");
 		vrm_mV_table = &vrm85_mV[0];
 		mV_vrm_table = &mV_vrm85[0];
 	} else {
-		printk (KERN_INFO PFX "Mobile VRM\n");
+		printk(KERN_INFO PFX "Mobile VRM\n");
 		if (cpu_model < CPU_NEHEMIAH)
 			return;
 		vrm_mV_table = &mobilevrm_mV[0];
@@ -523,7 +608,6 @@ static void __init longhaul_setup_voltagescaling(void)
 	/* Calculate kHz for one voltage step */
 	kHz_step = (highest_speed - min_vid_speed) / numvscales;
 
-
 	j = 0;
 	while (longhaul_table[j].frequency != CPUFREQ_TABLE_END) {
 		speed = longhaul_table[j].frequency;
@@ -531,15 +615,14 @@ static void __init longhaul_setup_voltagescaling(void)
 			pos = (speed - min_vid_speed) / kHz_step + minvid.pos;
 		else
 			pos = minvid.pos;
-		f_msr_table[longhaul_table[j].index].vrm = mV_vrm_table[pos];
-		f_msr_table[longhaul_table[j].index].pos = pos;
+		longhaul_table[j].index |= mV_vrm_table[pos] << 8;
+		vid = vrm_mV_table[mV_vrm_table[pos]];
+		printk(KERN_INFO PFX "f: %d kHz, index: %d, vid: %d mV\n", speed, j, vid.mV);
 		j++;
 	}
 
-	longhaul_pos = maxvid.pos;
 	can_scale_voltage = 1;
-	printk(KERN_INFO PFX "Voltage scaling enabled. "
-		"Use of \"conservative\" governor is highly recommended.\n");
+	printk(KERN_INFO PFX "Voltage scaling enabled.\n");
 }
 
 
@@ -553,15 +636,44 @@ static int longhaul_target(struct cpufreq_policy *policy,
 			    unsigned int target_freq, unsigned int relation)
 {
 	unsigned int table_index = 0;
-	unsigned int new_clock_ratio = 0;
+	unsigned int i;
+	unsigned int dir = 0;
+	u8 vid, current_vid;
 
 	if (cpufreq_frequency_table_target(policy, longhaul_table, target_freq, relation, &table_index))
 		return -EINVAL;
 
-	new_clock_ratio = longhaul_table[table_index].index & 0xFF;
-
-	longhaul_setstate(new_clock_ratio);
+	/* Don't set same frequency again */
+	if (longhaul_index == table_index)
+		return 0;
 
+	if (!can_scale_voltage)
+		longhaul_setstate(table_index);
+	else {
+		/* On test system voltage transitions exceeding single
+		 * step up or down were turning motherboard off. Both
+		 * "ondemand" and "userspace" are unsafe. C7 is doing
+		 * this in hardware, C3 is old and we need to do this
+		 * in software. */
+		i = longhaul_index;
+		current_vid = (longhaul_table[longhaul_index].index >> 8) & 0x1f;
+		if (table_index > longhaul_index)
+			dir = 1;
+		while (i != table_index) {
+			vid = (longhaul_table[i].index >> 8) & 0x1f;
+			if (vid != current_vid) {
+				longhaul_setstate(i);
+				current_vid = vid;
+				msleep(200);
+			}
+			if (dir)
+				i++;
+			else
+				i--;
+		}
+		longhaul_setstate(table_index);
+	}
+	longhaul_index = table_index;
 	return 0;
 }
 
@@ -590,11 +702,10 @@ static acpi_status longhaul_walk_callback(acpi_handle obj_handle,
 static int enable_arbiter_disable(void)
 {
 	struct pci_dev *dev;
-	int status;
+	int status = 1;
 	int reg;
 	u8 pci_cmd;
 
-	status = 1;
 	/* Find PLE133 host bridge */
 	reg = 0x78;
 	dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8601_0,
@@ -627,13 +738,17 @@ static int enable_arbiter_disable(void)
 	return 0;
 }
 
-static int longhaul_setup_vt8235(void)
+static int longhaul_setup_southbridge(void)
 {
 	struct pci_dev *dev;
 	u8 pci_cmd;
 
 	/* Find VT8235 southbridge */
 	dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235, NULL);
+	if (dev == NULL)
+	/* Find VT8237 southbridge */
+		dev = pci_get_device(PCI_VENDOR_ID_VIA,
+				     PCI_DEVICE_ID_VIA_8237, NULL);
 	if (dev != NULL) {
 		/* Set transition time to max */
 		pci_read_config_byte(dev, 0xec, &pci_cmd);
@@ -645,6 +760,14 @@ static int longhaul_setup_vt8235(void)
 		pci_read_config_byte(dev, 0xe5, &pci_cmd);
 		pci_cmd |= 1 << 7;
 		pci_write_config_byte(dev, 0xe5, pci_cmd);
+		/* Get address of ACPI registers block*/
+		pci_read_config_byte(dev, 0x81, &pci_cmd);
+		if (pci_cmd & 1 << 7) {
+			pci_read_config_dword(dev, 0x88, &acpi_regs_addr);
+			acpi_regs_addr &= 0xff00;
+			printk(KERN_INFO PFX "ACPI I/O at 0x%x\n", acpi_regs_addr);
+		}
+
 		pci_dev_put(dev);
 		return 1;
 	}
@@ -657,7 +780,6 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
 	char *cpuname=NULL;
 	int ret;
 	u32 lo, hi;
-	int vt8235_present;
 
 	/* Check what we have on this motherboard */
 	switch (c->x86_model) {
@@ -755,7 +877,7 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
 	};
 
 	/* Doesn't hurt */
-	vt8235_present = longhaul_setup_vt8235();
+	longhaul_setup_southbridge();
 
 	/* Find ACPI data for processor */
 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
@@ -765,35 +887,29 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
 	/* Check ACPI support for C3 state */
 	if (pr != NULL && longhaul_version == TYPE_POWERSAVER) {
 		cx = &pr->power.states[ACPI_STATE_C3];
-		if (cx->address > 0 && cx->latency <= 1000) {
+		if (cx->address > 0 && cx->latency <= 1000)
 			longhaul_flags |= USE_ACPI_C3;
-			goto print_support_type;
-		}
 	}
+	/* Disable if it isn't working */
+	if (disable_acpi_c3)
+		longhaul_flags &= ~USE_ACPI_C3;
 	/* Check if northbridge is friendly */
-	if (enable_arbiter_disable()) {
+	if (enable_arbiter_disable())
 		longhaul_flags |= USE_NORTHBRIDGE;
-		goto print_support_type;
-	}
-	/* Use VT8235 southbridge if present */
-	if (longhaul_version == TYPE_POWERSAVER && vt8235_present) {
-		longhaul_flags |= USE_VT8235;
-		goto print_support_type;
-	}
+
 	/* Check ACPI support for bus master arbiter disable */
-	if ((pr == NULL) || !(pr->flags.bm_control)) {
+	if (!(longhaul_flags & USE_ACPI_C3
+	     || longhaul_flags & USE_NORTHBRIDGE)
+	    && ((pr == NULL) || !(pr->flags.bm_control))) {
 		printk(KERN_ERR PFX
 			"No ACPI support. Unsupported northbridge.\n");
 		return -ENODEV;
 	}
 
-print_support_type:
 	if (longhaul_flags & USE_NORTHBRIDGE)
-		printk (KERN_INFO PFX "Using northbridge support.\n");
-	else if (longhaul_flags & USE_VT8235)
-		printk (KERN_INFO PFX "Using VT8235 support.\n");
-	else
-		printk (KERN_INFO PFX "Using ACPI support.\n");
+		printk(KERN_INFO PFX "Using northbridge support.\n");
+	if (longhaul_flags & USE_ACPI_C3)
+		printk(KERN_INFO PFX "Using ACPI support.\n");
 
 	ret = longhaul_get_ranges();
 	if (ret != 0)
@@ -885,8 +1001,20 @@ static void __exit longhaul_exit(void)
 	kfree(longhaul_table);
 }
 
+/* Even if BIOS is exporting ACPI C3 state, and it is used
+ * with success when CPU is idle, this state doesn't
+ * trigger frequency transition in some cases. */
+module_param (disable_acpi_c3, int, 0644);
+MODULE_PARM_DESC(disable_acpi_c3, "Don't use ACPI C3 support");
+/* Change CPU voltage with frequency. Very usefull to save
+ * power, but most VIA C3 processors aren't supporting it. */
 module_param (scale_voltage, int, 0644);
 MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor");
+/* Force revision key to 0 for processors which doesn't
+ * support voltage scaling, but are introducing itself as
+ * such. */
+module_param(revid_errata, int, 0644);
+MODULE_PARM_DESC(revid_errata, "Ignore CPU Revision ID");
 
 MODULE_AUTHOR ("Dave Jones <davej@codemonkey.org.uk>");
 MODULE_DESCRIPTION ("Longhaul driver for VIA Cyrix processors.");