10 files changed, 364 insertions, 49 deletions

diff --git a/arch/i386/kernel/cpu/cpufreq/Kconfig b/arch/i386/kernel/cpu/cpufreq/Kconfig
index f25ffd74235c..0f1eb507233b 100644
--- a/arch/i386/kernel/cpu/cpufreq/Kconfig
+++ b/arch/i386/kernel/cpu/cpufreq/Kconfig
@@ -23,7 +23,7 @@ config X86_ACPI_CPUFREQ
           If in doubt, say N.
 
 config ELAN_CPUFREQ
-        tristate "AMD Elan"
+        tristate "AMD Elan SC400 and SC410"
         select CPU_FREQ_TABLE
         depends on X86_ELAN
         ---help---
@@ -38,6 +38,18 @@ config ELAN_CPUFREQ
 
           If in doubt, say N.
 
+config SC520_CPUFREQ
+        tristate "AMD Elan SC520"
+        select CPU_FREQ_TABLE
+        depends on X86_ELAN
+        ---help---
+          This adds the CPUFreq driver for AMD Elan SC520 processor.
+
+          For details, take a look at <file:Documentation/cpu-freq/>.
+
+          If in doubt, say N.
+
+
 config X86_POWERNOW_K6
         tristate "AMD Mobile K6-2/K6-3 PowerNow!"
         select CPU_FREQ_TABLE
diff --git a/arch/i386/kernel/cpu/cpufreq/Makefile b/arch/i386/kernel/cpu/cpufreq/Makefile
index a922e97aeedd..2e894f1c8910 100644
--- a/arch/i386/kernel/cpu/cpufreq/Makefile
+++ b/arch/i386/kernel/cpu/cpufreq/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_X86_POWERNOW_K7)		+= powernow-k7.o
 obj-$(CONFIG_X86_POWERNOW_K8)           += powernow-k8.o
 obj-$(CONFIG_X86_LONGHAUL)              += longhaul.o
 obj-$(CONFIG_ELAN_CPUFREQ)              += elanfreq.o
+obj-$(CONFIG_SC520_CPUFREQ)             += sc520_freq.o
 obj-$(CONFIG_X86_LONGRUN)               += longrun.o  
 obj-$(CONFIG_X86_GX_SUSPMOD)            += gx-suspmod.o
 obj-$(CONFIG_X86_SPEEDSTEP_ICH)         += speedstep-ich.o
diff --git a/arch/i386/kernel/cpu/cpufreq/longhaul.c b/arch/i386/kernel/cpu/cpufreq/longhaul.c
index ab0f9f5aac11..04e3563da4fe 100644
--- a/arch/i386/kernel/cpu/cpufreq/longhaul.c
+++ b/arch/i386/kernel/cpu/cpufreq/longhaul.c
@@ -29,6 +29,7 @@
 #include <linux/cpufreq.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/pci.h>
 
 #include <asm/msr.h>
 #include <asm/timex.h>
@@ -119,7 +120,13 @@ static int longhaul_get_cpu_mult(void)
 static void do_powersaver(union msr_longhaul *longhaul,
                         unsigned int clock_ratio_index)
 {
+        struct pci_dev *dev;
+        unsigned long flags;
+        unsigned int tmp_mask;
         int version;
+        int i;
+        u16 pci_cmd;
+        u16 cmd_state[64];
 
         switch (cpu_model) {
         case CPU_EZRA_T:
@@ -137,17 +144,58 @@ static void do_powersaver(union msr_longhaul *longhaul,
         longhaul->bits.SoftBusRatio4 = (clock_ratio_index & 0x10) >> 4;
         longhaul->bits.EnableSoftBusRatio = 1;
         longhaul->bits.RevisionKey = 0;
-        local_irq_disable();
-        wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
+
+        preempt_disable();
+        local_irq_save(flags);
+
+        /*
+         * get current pci bus master state for all devices
+         * and clear bus master bit
+         */
+        dev = NULL;
+        i = 0;
+        do {
+                dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
+                if (dev != NULL) {
+                        pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
+                        cmd_state[i++] = pci_cmd;
+                        pci_cmd &= ~PCI_COMMAND_MASTER;
+                        pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
+                }
+        } while (dev != NULL);
+
+        tmp_mask=inb(0x21);     /* works on C3. save mask. */
+        outb(0xFE,0x21);        /* TMR0 only */
+        outb(0xFF,0x80);        /* delay */
+
         local_irq_enable();
+
+        __hlt();
+        wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
         __hlt();
 
+        local_irq_disable();
+
+        outb(tmp_mask,0x21);    /* restore mask */
+
+        /* restore pci bus master state for all devices */
+        dev = NULL;
+        i = 0;
+        do {
+                dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
+                if (dev != NULL) {
+                        pci_cmd = cmd_state[i++];
+                        pci_write_config_byte(dev, PCI_COMMAND, pci_cmd);
+                }
+        } while (dev != NULL);
+        local_irq_restore(flags);
+        preempt_enable();
+
+        /* disable bus ratio bit */
         rdmsrl(MSR_VIA_LONGHAUL, longhaul->val);
         longhaul->bits.EnableSoftBusRatio = 0;
         longhaul->bits.RevisionKey = version;
-        local_irq_disable();
         wrmsrl(MSR_VIA_LONGHAUL, longhaul->val);
-        local_irq_enable();
 }
 
 /**
@@ -578,7 +626,7 @@ static int __init longhaul_cpu_init(struct cpufreq_policy *policy)
                 longhaul_setup_voltagescaling();
 
         policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
-        policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
+        policy->cpuinfo.transition_latency = 200000;    /* nsec */
         policy->cur = calc_speed(longhaul_get_cpu_mult());
 
         ret = cpufreq_frequency_table_cpuinfo(policy, longhaul_table);
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k7.c b/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
index 913f652623d9..5c530064eb74 100644
--- a/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
+++ b/arch/i386/kernel/cpu/cpufreq/powernow-k7.c
@@ -23,6 +23,7 @@
 #include <linux/dmi.h>
 
 #include <asm/msr.h>
+#include <asm/timer.h>
 #include <asm/timex.h>
 #include <asm/io.h>
 #include <asm/system.h>
@@ -586,13 +587,17 @@ static int __init powernow_cpu_init (struct cpufreq_policy *policy)
 
         rdmsrl (MSR_K7_FID_VID_STATUS, fidvidstatus.val);
 
-        /* A K7 with powernow technology is set to max frequency by BIOS */
-        fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.MFID];
+        /* recalibrate cpu_khz */
+        result = recalibrate_cpu_khz();
+        if (result)
+                return result;
+
+        fsb = (10 * cpu_khz) / fid_codes[fidvidstatus.bits.CFID];
         if (!fsb) {
                 printk(KERN_WARNING PFX "can not determine bus frequency\n");
                 return -EINVAL;
         }
-        dprintk("FSB: %3d.%03d MHz\n", fsb/1000, fsb%1000);
+        dprintk("FSB: %3dMHz\n", fsb/1000);
 
         if (dmi_check_system(powernow_dmi_table) || acpi_force) {
                 printk (KERN_INFO PFX "PSB/PST known to be broken.  Trying ACPI instead\n");
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
index a65ff7e32e5d..10cc096c0ade 100644
--- a/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/i386/kernel/cpu/cpufreq/powernow-k8.c
@@ -4,7 +4,7 @@
  *  GNU general public license version 2. See "COPYING" or
  *  http://www.gnu.org/licenses/gpl.html
  *
- *  Support : paul.devriendt@amd.com
+ *  Support : mark.langsdorf@amd.com
  *
  *  Based on the powernow-k7.c module written by Dave Jones.
  *  (C) 2003 Dave Jones <davej@codemonkey.org.uk> on behalf of SuSE Labs
@@ -15,12 +15,13 @@
  *
  *  Valuable input gratefully received from Dave Jones, Pavel Machek,
  *  Dominik Brodowski, and others.
+ *  Originally developed by Paul Devriendt.
  *  Processor information obtained from Chapter 9 (Power and Thermal Management)
  *  of the "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD
  *  Opteron Processors" available for download from www.amd.com
  *
  *  Tables for specific CPUs can be infrerred from
- *      http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/30430.pdf
+ *     http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/30430.pdf
  */
 
 #include <linux/kernel.h>
@@ -30,6 +31,7 @@
 #include <linux/cpufreq.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/cpumask.h>
 
 #include <asm/msr.h>
 #include <asm/io.h>
@@ -42,7 +44,7 @@
 
 #define PFX "powernow-k8: "
 #define BFX PFX "BIOS error: "
-#define VERSION "version 1.00.09e"
+#define VERSION "version 1.40.2"
 #include "powernow-k8.h"
 
 /* serialize freq changes  */
@@ -50,6 +52,10 @@ static DECLARE_MUTEX(fidvid_sem);
 
 static struct powernow_k8_data *powernow_data[NR_CPUS];
 
+#ifndef CONFIG_SMP
+static cpumask_t cpu_core_map[1];
+#endif
+
 /* Return a frequency in MHz, given an input fid */
 static u32 find_freq_from_fid(u32 fid)
 {
@@ -274,11 +280,18 @@ static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid
 {
         u32 rvosteps = data->rvo;
         u32 savefid = data->currfid;
+        u32 maxvid, lo;
 
         dprintk("ph1 (cpu%d): start, currfid 0x%x, currvid 0x%x, reqvid 0x%x, rvo 0x%x\n",
                 smp_processor_id(),
                 data->currfid, data->currvid, reqvid, data->rvo);
 
+        rdmsr(MSR_FIDVID_STATUS, lo, maxvid);
+        maxvid = 0x1f & (maxvid >> 16);
+        dprintk("ph1 maxvid=0x%x\n", maxvid);
+        if (reqvid < maxvid) /* lower numbers are higher voltages */
+                reqvid = maxvid;
+
         while (data->currvid > reqvid) {
                 dprintk("ph1: curr 0x%x, req vid 0x%x\n",
                         data->currvid, reqvid);
@@ -286,8 +299,8 @@ static int core_voltage_pre_transition(struct powernow_k8_data *data, u32 reqvid
                         return 1;
         }
 
-        while ((rvosteps > 0)  && ((data->rvo + data->currvid) > reqvid)) {
-                if (data->currvid == 0) {
+        while ((rvosteps > 0) && ((data->rvo + data->currvid) > reqvid)) {
+                if (data->currvid == maxvid) {
                         rvosteps = 0;
                 } else {
                         dprintk("ph1: changing vid for rvo, req 0x%x\n",
@@ -671,7 +684,7 @@ static int find_psb_table(struct powernow_k8_data *data)
          * BIOS and Kernel Developer's Guide, which is available on
          * www.amd.com
          */
-        printk(KERN_ERR PFX "BIOS error - no PSB\n");
+        printk(KERN_INFO PFX "BIOS error - no PSB or ACPI _PSS objects\n");
         return -ENODEV;
 }
 
@@ -695,7 +708,7 @@ static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
         struct cpufreq_frequency_table *powernow_table;
 
         if (acpi_processor_register_performance(&data->acpi_data, data->cpu)) {
-                dprintk("register performance failed\n");
+                dprintk("register performance failed: bad ACPI data\n");
                 return -EIO;
         }
 
@@ -746,22 +759,23 @@ static int powernow_k8_cpu_init_acpi(struct powernow_k8_data *data)
                         continue;
                 }
 
-                if (fid < HI_FID_TABLE_BOTTOM) {
-                        if (cntlofreq) {
-                                /* if both entries are the same, ignore this
-                                 * one... 
-                                 */
-                                if ((powernow_table[i].frequency != powernow_table[cntlofreq].frequency) ||
-                                    (powernow_table[i].index != powernow_table[cntlofreq].index)) {
-                                        printk(KERN_ERR PFX "Too many lo freq table entries\n");
-                                        goto err_out_mem;
-                                }
-                                
-                                dprintk("double low frequency table entry, ignoring it.\n");
-                                powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
-                                continue;
-                        } else
-                                cntlofreq = i;
+                /* verify only 1 entry from the lo frequency table */
+                if (fid < HI_FID_TABLE_BOTTOM) {
+                        if (cntlofreq) {
+                                /* if both entries are the same, ignore this
+                                 * one... 
+                                 */
+                                if ((powernow_table[i].frequency != powernow_table[cntlofreq].frequency) ||
+                                    (powernow_table[i].index != powernow_table[cntlofreq].index)) {
+                                        printk(KERN_ERR PFX "Too many lo freq table entries\n");
+                                        goto err_out_mem;
+                                }
+
+                                dprintk("double low frequency table entry, ignoring it.\n");
+                                powernow_table[i].frequency = CPUFREQ_ENTRY_INVALID;
+                                continue;
+                        } else
+                                cntlofreq = i;
                 }
 
                 if (powernow_table[i].frequency != (data->acpi_data.states[i].core_frequency * 1000)) {
@@ -816,7 +830,7 @@ static int transition_frequency(struct powernow_k8_data *data, unsigned int inde
 {
         u32 fid;
         u32 vid;
-        int res;
+        int res, i;
         struct cpufreq_freqs freqs;
 
         dprintk("cpu %d transition to index %u\n", smp_processor_id(), index);
@@ -841,7 +855,8 @@ static int transition_frequency(struct powernow_k8_data *data, unsigned int inde
         }
 
         if ((fid < HI_FID_TABLE_BOTTOM) && (data->currfid < HI_FID_TABLE_BOTTOM)) {
-                printk("ignoring illegal change in lo freq table-%x to 0x%x\n",
+                printk(KERN_ERR PFX
+                       "ignoring illegal change in lo freq table-%x to 0x%x\n",
                        data->currfid, fid);
                 return 1;
         }
@@ -850,18 +865,20 @@ static int transition_frequency(struct powernow_k8_data *data, unsigned int inde
                 smp_processor_id(), fid, vid);
 
         freqs.cpu = data->cpu;
-
         freqs.old = find_khz_freq_from_fid(data->currfid);
         freqs.new = find_khz_freq_from_fid(fid);
-        cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+        for_each_cpu_mask(i, cpu_core_map[data->cpu]) {
+                freqs.cpu = i;
+                cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+        }
 
-        down(&fidvid_sem);
         res = transition_fid_vid(data, fid, vid);
-        up(&fidvid_sem);
 
         freqs.new = find_khz_freq_from_fid(data->currfid);
-        cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
-
+        for_each_cpu_mask(i, cpu_core_map[data->cpu]) {
+                freqs.cpu = i;
+                cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+        }
         return res;
 }
 
@@ -874,6 +891,7 @@ static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsi
         u32 checkvid = data->currvid;
         unsigned int newstate;
         int ret = -EIO;
+        int i;
 
         /* only run on specific CPU from here on */
         oldmask = current->cpus_allowed;
@@ -902,22 +920,41 @@ static int powernowk8_target(struct cpufreq_policy *pol, unsigned targfreq, unsi
                 data->currfid, data->currvid);
 
         if ((checkvid != data->currvid) || (checkfid != data->currfid)) {
-                printk(KERN_ERR PFX
-                       "error - out of sync, fid 0x%x 0x%x, vid 0x%x 0x%x\n",
-                       checkfid, data->currfid, checkvid, data->currvid);
+                printk(KERN_INFO PFX
+                        "error - out of sync, fix 0x%x 0x%x, vid 0x%x 0x%x\n",
+                        checkfid, data->currfid, checkvid, data->currvid);
         }
 
         if (cpufreq_frequency_table_target(pol, data->powernow_table, targfreq, relation, &newstate))
                 goto err_out;
 
+        down(&fidvid_sem);
+
+        for_each_cpu_mask(i, cpu_core_map[pol->cpu]) {
+                /* make sure the sibling is initialized */
+                if (!powernow_data[i]) {
+                        ret = 0;
+                        up(&fidvid_sem);
+                        goto err_out;
+                }
+        }
+
         powernow_k8_acpi_pst_values(data, newstate);
 
         if (transition_frequency(data, newstate)) {
                 printk(KERN_ERR PFX "transition frequency failed\n");
                 ret = 1;
+                up(&fidvid_sem);
                 goto err_out;
         }
 
+        /* Update all the fid/vids of our siblings */
+        for_each_cpu_mask(i, cpu_core_map[pol->cpu]) {
+                powernow_data[i]->currvid = data->currvid;
+                powernow_data[i]->currfid = data->currfid;
+        }       
+        up(&fidvid_sem);
+
         pol->cur = find_khz_freq_from_fid(data->currfid);
         ret = 0;
 
@@ -962,7 +999,7 @@ static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
                  */
 
                 if ((num_online_cpus() != 1) || (num_possible_cpus() != 1)) {
-                        printk(KERN_INFO PFX "MP systems not supported by PSB BIOS structure\n");
+                        printk(KERN_ERR PFX "MP systems not supported by PSB BIOS structure\n");
                         kfree(data);
                         return -ENODEV;
                 }
@@ -1003,6 +1040,7 @@ static int __init powernowk8_cpu_init(struct cpufreq_policy *pol)
         schedule();
 
         pol->governor = CPUFREQ_DEFAULT_GOVERNOR;
+        pol->cpus = cpu_core_map[pol->cpu];
 
         /* Take a crude guess here. 
          * That guess was in microseconds, so multiply with 1000 */
@@ -1069,7 +1107,7 @@ static unsigned int powernowk8_get (unsigned int cpu)
                 return 0;
         }
         preempt_disable();
-
+        
         if (query_current_values_with_pending_wait(data))
                 goto out;
 
@@ -1127,9 +1165,10 @@ static void __exit powernowk8_exit(void)
         cpufreq_unregister_driver(&cpufreq_amd64_driver);
 }
 
-MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com>");
+MODULE_AUTHOR("Paul Devriendt <paul.devriendt@amd.com> and Mark Langsdorf <mark.langsdorf@amd.com.");
 MODULE_DESCRIPTION("AMD Athlon 64 and Opteron processor frequency driver.");
 MODULE_LICENSE("GPL");
 
 late_initcall(powernowk8_init);
 module_exit(powernowk8_exit);
+
diff --git a/arch/i386/kernel/cpu/cpufreq/powernow-k8.h b/arch/i386/kernel/cpu/cpufreq/powernow-k8.h
index 63ebc8470f52..9ed5bf221cb7 100644
--- a/arch/i386/kernel/cpu/cpufreq/powernow-k8.h
+++ b/arch/i386/kernel/cpu/cpufreq/powernow-k8.h
@@ -174,3 +174,18 @@ static int core_voltage_post_transition(struct powernow_k8_data *data, u32 reqvi
 static int core_frequency_transition(struct powernow_k8_data *data, u32 reqfid);
 
 static void powernow_k8_acpi_pst_values(struct powernow_k8_data *data, unsigned int index);
+
+#ifndef for_each_cpu_mask
+#define for_each_cpu_mask(i,mask) for (i=0;i<1;i++)
+#endif
+                                                                                
+#ifdef CONFIG_SMP
+static inline void define_siblings(int cpu, cpumask_t cpu_sharedcore_mask[])
+{
+}
+#else
+static inline void define_siblings(int cpu, cpumask_t cpu_sharedcore_mask[])
+{
+        cpu_set(0, cpu_sharedcore_mask[0]);
+}
+#endif
diff --git a/arch/i386/kernel/cpu/cpufreq/sc520_freq.c b/arch/i386/kernel/cpu/cpufreq/sc520_freq.c
new file mode 100644
index 000000000000..ef457d50f4ac
--- /dev/null
+++ b/arch/i386/kernel/cpu/cpufreq/sc520_freq.c
@@ -0,0 +1,186 @@
+/*
+ *      sc520_freq.c: cpufreq driver for the AMD Elan sc520
+ *
+ *      Copyright (C) 2005 Sean Young <sean@mess.org>
+ *
+ *      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.
+ *
+ *      Based on elanfreq.c
+ *
+ *      2005-03-30: - initial revision
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/delay.h>
+#include <linux/cpufreq.h>
+
+#include <asm/msr.h>
+#include <asm/timex.h>
+#include <asm/io.h>
+
+#define MMCR_BASE       0xfffef000      /* The default base address */
+#define OFFS_CPUCTL     0x2   /* CPU Control Register */
+
+static __u8 __iomem *cpuctl;
+
+#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "sc520_freq", msg)
+
+static struct cpufreq_frequency_table sc520_freq_table[] = {
+        {0x01,  100000},
+        {0x02,  133000},
+        {0,     CPUFREQ_TABLE_END},
+};
+
+static unsigned int sc520_freq_get_cpu_frequency(unsigned int cpu)
+{
+        u8 clockspeed_reg = *cpuctl;
+
+        switch (clockspeed_reg & 0x03) {
+        default:
+                printk(KERN_ERR "sc520_freq: error: cpuctl register has unexpected value %02x\n", clockspeed_reg);
+        case 0x01:
+                return 100000;
+        case 0x02:
+                return 133000;
+        }
+}
+
+static void sc520_freq_set_cpu_state (unsigned int state)
+{
+
+        struct cpufreq_freqs    freqs;
+        u8 clockspeed_reg;
+
+        freqs.old = sc520_freq_get_cpu_frequency(0);
+        freqs.new = sc520_freq_table[state].frequency;
+        freqs.cpu = 0; /* AMD Elan is UP */
+
+        cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+        dprintk("attempting to set frequency to %i kHz\n",
+                        sc520_freq_table[state].frequency);
+
+        local_irq_disable();
+
+        clockspeed_reg = *cpuctl & ~0x03;
+        *cpuctl = clockspeed_reg | sc520_freq_table[state].index;
+
+        local_irq_enable();
+
+        cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+};
+
+static int sc520_freq_verify (struct cpufreq_policy *policy)
+{
+        return cpufreq_frequency_table_verify(policy, &sc520_freq_table[0]);
+}
+
+static int sc520_freq_target (struct cpufreq_policy *policy,
+                            unsigned int target_freq,
+                            unsigned int relation)
+{
+        unsigned int newstate = 0;
+
+        if (cpufreq_frequency_table_target(policy, sc520_freq_table, target_freq, relation, &newstate))
+                return -EINVAL;
+
+        sc520_freq_set_cpu_state(newstate);
+
+        return 0;
+}
+
+
+/*
+ *      Module init and exit code
+ */
+
+static int sc520_freq_cpu_init(struct cpufreq_policy *policy)
+{
+        struct cpuinfo_x86 *c = cpu_data;
+        int result;
+
+        /* capability check */
+        if (c->x86_vendor != X86_VENDOR_AMD ||
+            c->x86 != 4 || c->x86_model != 9)
+                return -ENODEV;
+
+        /* cpuinfo and default policy values */
+        policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+        policy->cpuinfo.transition_latency = 1000000; /* 1ms */
+        policy->cur = sc520_freq_get_cpu_frequency(0);
+
+        result = cpufreq_frequency_table_cpuinfo(policy, sc520_freq_table);
+        if (result)
+                return (result);
+
+        cpufreq_frequency_table_get_attr(sc520_freq_table, policy->cpu);
+
+        return 0;
+}
+
+
+static int sc520_freq_cpu_exit(struct cpufreq_policy *policy)
+{
+        cpufreq_frequency_table_put_attr(policy->cpu);
+        return 0;
+}
+
+
+static struct freq_attr* sc520_freq_attr[] = {
+        &cpufreq_freq_attr_scaling_available_freqs,
+        NULL,
+};
+
+
+static struct cpufreq_driver sc520_freq_driver = {
+        .get    = sc520_freq_get_cpu_frequency,
+        .verify = sc520_freq_verify,
+        .target = sc520_freq_target,
+        .init   = sc520_freq_cpu_init,
+        .exit   = sc520_freq_cpu_exit,
+        .name   = "sc520_freq",
+        .owner  = THIS_MODULE,
+        .attr   = sc520_freq_attr,
+};
+
+
+static int __init sc520_freq_init(void)
+{
+        struct cpuinfo_x86 *c = cpu_data;
+
+        /* Test if we have the right hardware */
+        if(c->x86_vendor != X86_VENDOR_AMD ||
+                                c->x86 != 4 || c->x86_model != 9) {
+                dprintk("no Elan SC520 processor found!\n");
+                return -ENODEV;
+        }
+        cpuctl = ioremap((unsigned long)(MMCR_BASE + OFFS_CPUCTL), 1);
+        if(!cpuctl) {
+                printk(KERN_ERR "sc520_freq: error: failed to remap memory\n");
+                return -ENOMEM;
+        }
+
+        return cpufreq_register_driver(&sc520_freq_driver);
+}
+
+
+static void __exit sc520_freq_exit(void)
+{
+        cpufreq_unregister_driver(&sc520_freq_driver);
+        iounmap(cpuctl);
+}
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sean Young <sean@mess.org>");
+MODULE_DESCRIPTION("cpufreq driver for AMD's Elan sc520 CPU");
+
+module_init(sc520_freq_init);
+module_exit(sc520_freq_exit);
+
diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c b/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
index 07d5612dc00f..7dcbf70fc16f 100644
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.c
@@ -54,6 +54,8 @@ enum {
         CPU_DOTHAN_A1,
         CPU_DOTHAN_A2,
         CPU_DOTHAN_B0,
+        CPU_MP4HT_D0,
+        CPU_MP4HT_E0,
 };
 
 static const struct cpu_id cpu_ids[] = {
@@ -61,6 +63,8 @@ static const struct cpu_id cpu_ids[] = {
         [CPU_DOTHAN_A1] = { 6, 13, 1 },
         [CPU_DOTHAN_A2] = { 6, 13, 2 },
         [CPU_DOTHAN_B0] = { 6, 13, 6 },
+        [CPU_MP4HT_D0]  = {15,  3, 4 },
+        [CPU_MP4HT_E0]  = {15,  4, 1 },
 };
 #define N_IDS   (sizeof(cpu_ids)/sizeof(cpu_ids[0]))
 
@@ -226,6 +230,8 @@ static struct cpu_model models[] =
         { &cpu_ids[CPU_DOTHAN_A1], NULL, 0, NULL },
         { &cpu_ids[CPU_DOTHAN_A2], NULL, 0, NULL },
         { &cpu_ids[CPU_DOTHAN_B0], NULL, 0, NULL },
+        { &cpu_ids[CPU_MP4HT_D0], NULL, 0, NULL },
+        { &cpu_ids[CPU_MP4HT_E0], NULL, 0, NULL },
 
         { NULL, }
 };
diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
index 8ba430a9c3a2..d368b3f5fce8 100644
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-lib.c
@@ -336,7 +336,7 @@ unsigned int speedstep_get_freqs(unsigned int processor,
         if (!prev_speed)
                 return -EIO;
 
-        dprintk("previous seped is %u\n", prev_speed);
+        dprintk("previous speed is %u\n", prev_speed);
         
         local_irq_save(flags);
 
@@ -348,7 +348,7 @@ unsigned int speedstep_get_freqs(unsigned int processor,
                 goto out;
         }
 
-        dprintk("low seped is %u\n", *low_speed);
+        dprintk("low speed is %u\n", *low_speed);
 
         /* switch to high state */
         set_state(SPEEDSTEP_HIGH);
@@ -358,7 +358,7 @@ unsigned int speedstep_get_freqs(unsigned int processor,
                 goto out;
         }
 
-        dprintk("high seped is %u\n", *high_speed);
+        dprintk("high speed is %u\n", *high_speed);
 
         if (*low_speed == *high_speed) {
                 ret = -ENODEV;
diff --git a/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c b/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c
index 79440b3f087e..b25fb6b635ae 100644
--- a/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c
+++ b/arch/i386/kernel/cpu/cpufreq/speedstep-smi.c
@@ -357,6 +357,9 @@ static int __init speedstep_init(void)
         case SPEEDSTEP_PROCESSOR_PIII_C:
         case SPEEDSTEP_PROCESSOR_PIII_C_EARLY:
                 break;
+        case SPEEDSTEP_PROCESSOR_P4M:
+                printk(KERN_INFO "speedstep-smi: you're trying to use this cpufreq driver on a Pentium 4-based CPU. Most likely it will not work.\n");
+                break;
         default:
                 speedstep_processor = 0;
         }