[CPUFREQ] dual-core powernow-k8

With the release of the dual-core AMD Opterons last week,
it's high time that cpufreq supported them.  The attached
patch applies cleanly to 2.6.12-rc3 and updates powernow-k8
to support the latest Athlon 64 and Opteron processors.

Update the driver to version 1.40.0 and provide support
for dual-core processors.

Signed-off-by: Mark Langsdorf <mark.langsdorf@amd.com>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 76 insertions, 37 deletions

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);
+