Re: [patches] 2.6.2 to 2.6.3 regression: powernow-k8 doesn't work anymore

[Pavel Machek <pavel@suse.cz>]

Hi!

> >Andrew, we made mistake in 2.6.2 to 2.6.3 update; this one should fix
> >it. Please apply,
> >
> >									Pavel
> >
> >--- clean/arch/i386/kernel/cpu/cpufreq/powernow-k8.c	2004-02-22 
> >23:30:27.000000000 +0100
> >+++ linux/arch/i386/kernel/cpu/cpufreq/powernow-k8.c	2004-02-22 
> >23:29:38.000000000 +0100
> >@@ -521,7 +517,8 @@
> > 		}
> > 		if ((pst[j].fid > MAX_FID)
> > 		    || (pst[j].fid & 1)
> >-		    || (pst[j].fid < HI_FID_TABLE_BOTTOM)){
> >+		    || (j && (pst[j].fid < HI_FID_TABLE_BOTTOM))) {
> >+			/* Only first fid is allowed to be in "low" range */
> > 			printk(KERN_ERR PFX "fid %d invalid : 0x%x\n", j, 
> > 			pst[j].fid);
> > 			return -EINVAL;
> > 		}
> >
> >
> 
> While this patch seems to fix one problem, there's still another
>one:

Sorry, I do not have production hardware here.
 
> powernow-k8: Found AMD64 processor supporting PowerNow (version 1.00.08a)
> powernow-k8: voltage stable in 100 usec, ramp voltage offset: 2, 
> isochronous relief time: 3, maximum voltage step: 0
> powernow-k8: pll lock time: 0x2, maxfid 0xc (2000 MHz), maxvid 0x0
> powernow-k8:    0 : fid 0x0 (800 MHz), vid 0xa
> powernow-k8:    1 : fid 0xa (1800 MHz), vid 0x6
> powernow-k8:    2 : fid 0xc (2000 MHz), vid 0x2
> powernow-k8: currfid 0xc (2000 MHz), currvid 0x0
> powernow-k8: BIOS error: currfid/vid do not match PST, ignoring
> powernow-k8: cpu_init done, current fid 0xc, vid 0x0
> powernow-k8: ph2 null fid transition 0xc
> 
> (this looks similar to what the working version from 2.6.2 prints)
> 
> but...:
> 
> > cat /proc/cpufreq
> 
>           minimum CPU frequency  -  maximum CPU frequency  -  policy
> CPU  0         2000 kHz (100 %)  -       2000 kHz (100 %)  -  powersave
> 
> Well... looks like a funny idea to run an Athlon64 at 2MHz, but it feels
> much faster... but what is really a problem: No matter what I "echo" into
> /proc/cpufreq, nothing changes.
> 
> A factor 1000 lost somewhere?

Yes.

Try this one. [Warning: extremely ugly hand-edited patch follows;
taking akpm off Cc list, I do not want him to even see it]

								Pavel

--- clean/arch/i386/kernel/cpu/cpufreq/powernow-k8.c	2004-02-20 12:29:10.000000000 +0100
+++ linux/arch/i386/kernel/cpu/cpufreq/powernow-k8.c	2004-02-23 21:06:01.000000000 +0100
@@ -8,6 +8,8 @@
  *
  *  Based on the powernow-k7.c module written by Dave Jones.
  *  (C) 2003 Dave Jones <davej@codemonkey.ork.uk> on behalf of SuSE Labs
+ *  (C) 2004 Dominik Brodowski <linux@brodo.de>
+ *  (C) 2004 Pavel Machek <pavel@suse.cz>
  *  Licensed under the terms of the GNU GPL License version 2.
  *  Based upon datasheets & sample CPUs kindly provided by AMD.
  *
@@ -34,10 +36,6 @@
 #define VERSION "version 1.00.08a"
 #include "powernow-k8.h"
 
-#ifdef CONFIG_PREEMPT
-#warning this driver has not been tested on a preempt system
-#endif
-
 static u32 vstable;	/* voltage stabalization time, from PSB, units 20 us */
 static u32 plllock;	/* pll lock time, from PSB, units 1 us */
 static u32 numps;	/* number of p-states, from PSB */
@@ -521,7 +519,8 @@
 		}
 		if ((pst[j].fid > MAX_FID)
 		    || (pst[j].fid & 1)
-		    || (pst[j].fid < HI_FID_TABLE_BOTTOM)){
+		    || (j && (pst[j].fid < HI_FID_TABLE_BOTTOM))) {
+			/* Only first fid is allowed to be in "low" range */
 			printk(KERN_ERR PFX "fid %d invalid : 0x%x\n", j, pst[j].fid);
 			return -EINVAL;
 		}
@@ -548,6 +547,7 @@
 	unsigned int i, j;
 	u32 mvs;
 	u8 maxvid;
+	int arima = 0;
 
 	for (i = 0xc0000; i < 0xffff0; i += 0x10) {
 		/* Scan BIOS looking for the signature. */
@@ -589,7 +589,7 @@
 		dprintk(KERN_DEBUG PFX "numpst: 0x%x\n", psb->numpst);
 		if (psb->numpst != 1) {
 			printk(KERN_ERR BFX "numpst must be 1\n");
-			return -ENODEV;
+			arima = 0;
 		}
 
 		dprintk(KERN_DEBUG PFX "cpuid: 0x%x\n", psb->cpuid);
@@ -601,7 +601,7 @@
 		printk("maxfid 0x%x (%d MHz), maxvid 0x%x\n", 
 		       psb->maxfid, find_freq_from_fid(psb->maxfid), maxvid);
 
-		numps = psb->numpstates;
+		numps = arima ? 3 : psb->numpstates;
 		if (numps < 2) {
 			printk(KERN_ERR BFX "no p states to transition\n");
 			return -ENODEV;
@@ -626,8 +626,10 @@
 		}
 
 		pst = (struct pst_s *) (psb + 1);
-		if (check_pst_table(pst, maxvid))
-			return -EINVAL;
+		if (check_pst_table(pst, maxvid)) {
+			if (!arima)
+				return -EINVAL;
+		}
 
 		powernow_table = kmalloc((sizeof(struct cpufreq_frequency_table) * (numps + 1)), GFP_KERNEL);
 		if (!powernow_table) {
@@ -635,13 +637,24 @@
 			return -ENOMEM;
 		}
 
-		for (j = 0; j < numps; j++) {
-			printk(KERN_INFO PFX "   %d : fid 0x%x (%d MHz), vid 0x%x\n", j,
-			       pst[j].fid, find_freq_from_fid(pst[j].fid), pst[j].vid);
+		for (j = 0; j < numps; j++) {
 			powernow_table[j].index = pst[j].fid; /* lower 8 bits */
 			powernow_table[j].index |= (pst[j].vid << 8); /* upper 8 bits */
-			powernow_table[j].frequency = find_freq_from_fid(pst[j].fid);
 		}
+
+		if (arima) {
+			powernow_table[1].index = 0x0608;
+			powernow_table[2].index = 0x020a;
+		}
+
+		for (j = 0; j < numps; j++) {
+			powernow_table[j].frequency = find_freq_from_fid(powernow_table[j].index & 0xff)*1000;
+			printk(KERN_INFO PFX "   %d : fid 0x%x (%d MHz), vid 0x%x\n", j,
+			       powernow_table[j].index & 0xff, 
+			       powernow_table[j].frequency/1000,
+			       powernow_table[j].index >> 8);
+		}
+
 		powernow_table[numps].frequency = CPUFREQ_TABLE_END;
 		powernow_table[numps].index = 0;
 


-- 
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]