linux/drivers/hwmon/hwmon-vid.c
Jean Delvare 5bed13f580 hwmon-vid: Ignore 6th VID pin of AMD family 0Fh processors
We had a report about a mainboard for AMD family 0Fh processors not
routing the 6th VID pin from the CPU to the hardware monitoring chip.

While the vendor should have wired the pin (or, failing that, should
have hardwired it to level high rather than low), the fact is that
none of these processors are currently known to operate at the lower
voltage levels which require the 6th VID pin. So, as a practical
workaround, I propose to ignore the 6th VID pin for these CPUs.

If this decision ever causes problems, we'll reconsider.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Frank Myhr <fmyhr@fhmtech.com>
Tested-by: Hleb Valoshka <375gnu@gmail.com>
Cc: Rudolf Marek <r.marek@assembler.cz>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
2009-09-15 17:18:11 +02:00

269 lines
8.8 KiB
C

/*
* hwmon-vid.c - VID/VRM/VRD voltage conversions
*
* Copyright (c) 2004 Rudolf Marek <r.marek@assembler.cz>
*
* Partly imported from i2c-vid.h of the lm_sensors project
* Copyright (c) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
* With assistance from Trent Piepho <xyzzy@speakeasy.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.
*
* This program is distributed in the hope that 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/hwmon-vid.h>
/*
* Common code for decoding VID pins.
*
* References:
*
* For VRM 8.4 to 9.1, "VRM x.y DC-DC Converter Design Guidelines",
* available at http://developer.intel.com/.
*
* For VRD 10.0 and up, "VRD x.y Design Guide",
* available at http://developer.intel.com/.
*
* AMD Athlon 64 and AMD Opteron Processors, AMD Publication 26094,
* http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26094.PDF
* Table 74. VID Code Voltages
* This corresponds to an arbitrary VRM code of 24 in the functions below.
* These CPU models (K8 revision <= E) have 5 VID pins. See also:
* Revision Guide for AMD Athlon 64 and AMD Opteron Processors, AMD Publication 25759,
* http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/25759.pdf
*
* AMD NPT Family 0Fh Processors, AMD Publication 32559,
* http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/32559.pdf
* Table 71. VID Code Voltages
* This corresponds to an arbitrary VRM code of 25 in the functions below.
* These CPU models (K8 revision >= F) have 6 VID pins. See also:
* Revision Guide for AMD NPT Family 0Fh Processors, AMD Publication 33610,
* http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/33610.pdf
*
* The 17 specification is in fact Intel Mobile Voltage Positioning -
* (IMVP-II). You can find more information in the datasheet of Max1718
* http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2452
*
* The 13 specification corresponds to the Intel Pentium M series. There
* doesn't seem to be any named specification for these. The conversion
* tables are detailed directly in the various Pentium M datasheets:
* http://www.intel.com/design/intarch/pentiumm/docs_pentiumm.htm
*
* The 14 specification corresponds to Intel Core series. There
* doesn't seem to be any named specification for these. The conversion
* tables are detailed directly in the various Pentium Core datasheets:
* http://www.intel.com/design/mobile/datashts/309221.htm
*
* The 110 (VRM 11) specification corresponds to Intel Conroe based series.
* http://www.intel.com/design/processor/applnots/313214.htm
*/
/*
* vrm is the VRM/VRD document version multiplied by 10.
* val is the 4-bit or more VID code.
* Returned value is in mV to avoid floating point in the kernel.
* Some VID have some bits in uV scale, this is rounded to mV.
*/
int vid_from_reg(int val, u8 vrm)
{
int vid;
switch(vrm) {
case 100: /* VRD 10.0 */
/* compute in uV, round to mV */
val &= 0x3f;
if((val & 0x1f) == 0x1f)
return 0;
if((val & 0x1f) <= 0x09 || val == 0x0a)
vid = 1087500 - (val & 0x1f) * 25000;
else
vid = 1862500 - (val & 0x1f) * 25000;
if(val & 0x20)
vid -= 12500;
return((vid + 500) / 1000);
case 110: /* Intel Conroe */
/* compute in uV, round to mV */
val &= 0xff;
if (val < 0x02 || val > 0xb2)
return 0;
return((1600000 - (val - 2) * 6250 + 500) / 1000);
case 24: /* Athlon64 & Opteron */
val &= 0x1f;
if (val == 0x1f)
return 0;
/* fall through */
case 25: /* AMD NPT 0Fh */
val &= 0x3f;
return (val < 32) ? 1550 - 25 * val
: 775 - (25 * (val - 31)) / 2;
case 91: /* VRM 9.1 */
case 90: /* VRM 9.0 */
val &= 0x1f;
return(val == 0x1f ? 0 :
1850 - val * 25);
case 85: /* VRM 8.5 */
val &= 0x1f;
return((val & 0x10 ? 25 : 0) +
((val & 0x0f) > 0x04 ? 2050 : 1250) -
((val & 0x0f) * 50));
case 84: /* VRM 8.4 */
val &= 0x0f;
/* fall through */
case 82: /* VRM 8.2 */
val &= 0x1f;
return(val == 0x1f ? 0 :
val & 0x10 ? 5100 - (val) * 100 :
2050 - (val) * 50);
case 17: /* Intel IMVP-II */
val &= 0x1f;
return(val & 0x10 ? 975 - (val & 0xF) * 25 :
1750 - val * 50);
case 13:
val &= 0x3f;
return(1708 - val * 16);
case 14: /* Intel Core */
/* compute in uV, round to mV */
val &= 0x7f;
return(val > 0x77 ? 0 : (1500000 - (val * 12500) + 500) / 1000);
default: /* report 0 for unknown */
if (vrm)
printk(KERN_WARNING "hwmon-vid: Requested unsupported "
"VRM version (%u)\n", (unsigned int)vrm);
return 0;
}
}
/*
* After this point is the code to automatically determine which
* VRM/VRD specification should be used depending on the CPU.
*/
struct vrm_model {
u8 vendor;
u8 eff_family;
u8 eff_model;
u8 eff_stepping;
u8 vrm_type;
};
#define ANY 0xFF
#ifdef CONFIG_X86
/*
* The stepping parameter is highest acceptable stepping for current line.
* The model match must be exact for 4-bit values. For model values 0x10
* and above (extended model), all models below the parameter will match.
*/
static struct vrm_model vrm_models[] = {
{X86_VENDOR_AMD, 0x6, ANY, ANY, 90}, /* Athlon Duron etc */
{X86_VENDOR_AMD, 0xF, 0x3F, ANY, 24}, /* Athlon 64, Opteron */
/* In theory, all NPT family 0Fh processors have 6 VID pins and should
thus use vrm 25, however in practice not all mainboards route the
6th VID pin because it is never needed. So we use the 5 VID pin
variant (vrm 24) for the models which exist today. */
{X86_VENDOR_AMD, 0xF, 0x7F, ANY, 24}, /* NPT family 0Fh */
{X86_VENDOR_AMD, 0xF, ANY, ANY, 25}, /* future fam. 0Fh */
{X86_VENDOR_AMD, 0x10, ANY, ANY, 25}, /* NPT family 10h */
{X86_VENDOR_INTEL, 0x6, 0x9, ANY, 13}, /* Pentium M (130 nm) */
{X86_VENDOR_INTEL, 0x6, 0xB, ANY, 85}, /* Tualatin */
{X86_VENDOR_INTEL, 0x6, 0xD, ANY, 13}, /* Pentium M (90 nm) */
{X86_VENDOR_INTEL, 0x6, 0xE, ANY, 14}, /* Intel Core (65 nm) */
{X86_VENDOR_INTEL, 0x6, 0xF, ANY, 110}, /* Intel Conroe */
{X86_VENDOR_INTEL, 0x6, ANY, ANY, 82}, /* any P6 */
{X86_VENDOR_INTEL, 0xF, 0x0, ANY, 90}, /* P4 */
{X86_VENDOR_INTEL, 0xF, 0x1, ANY, 90}, /* P4 Willamette */
{X86_VENDOR_INTEL, 0xF, 0x2, ANY, 90}, /* P4 Northwood */
{X86_VENDOR_INTEL, 0xF, ANY, ANY, 100}, /* Prescott and above assume VRD 10 */
{X86_VENDOR_CENTAUR, 0x6, 0x7, ANY, 85}, /* Eden ESP/Ezra */
{X86_VENDOR_CENTAUR, 0x6, 0x8, 0x7, 85}, /* Ezra T */
{X86_VENDOR_CENTAUR, 0x6, 0x9, 0x7, 85}, /* Nemiah */
{X86_VENDOR_CENTAUR, 0x6, 0x9, ANY, 17}, /* C3-M, Eden-N */
{X86_VENDOR_CENTAUR, 0x6, 0xA, 0x7, 0}, /* No information */
{X86_VENDOR_CENTAUR, 0x6, 0xA, ANY, 13}, /* C7, Esther */
{X86_VENDOR_UNKNOWN, ANY, ANY, ANY, 0} /* stop here */
};
static u8 find_vrm(u8 eff_family, u8 eff_model, u8 eff_stepping, u8 vendor)
{
int i = 0;
while (vrm_models[i].vendor!=X86_VENDOR_UNKNOWN) {
if (vrm_models[i].vendor==vendor)
if ((vrm_models[i].eff_family==eff_family)
&& ((vrm_models[i].eff_model==eff_model) ||
(vrm_models[i].eff_model >= 0x10 &&
eff_model <= vrm_models[i].eff_model) ||
(vrm_models[i].eff_model==ANY)) &&
(eff_stepping <= vrm_models[i].eff_stepping))
return vrm_models[i].vrm_type;
i++;
}
return 0;
}
u8 vid_which_vrm(void)
{
struct cpuinfo_x86 *c = &cpu_data(0);
u32 eax;
u8 eff_family, eff_model, eff_stepping, vrm_ret;
if (c->x86 < 6) /* Any CPU with family lower than 6 */
return 0; /* doesn't have VID and/or CPUID */
eax = cpuid_eax(1);
eff_family = ((eax & 0x00000F00)>>8);
eff_model = ((eax & 0x000000F0)>>4);
eff_stepping = eax & 0xF;
if (eff_family == 0xF) { /* use extended model & family */
eff_family += ((eax & 0x00F00000)>>20);
eff_model += ((eax & 0x000F0000)>>16)<<4;
}
vrm_ret = find_vrm(eff_family, eff_model, eff_stepping, c->x86_vendor);
if (vrm_ret == 0)
printk(KERN_INFO "hwmon-vid: Unknown VRM version of your "
"x86 CPU\n");
return vrm_ret;
}
/* and now for something completely different for the non-x86 world */
#else
u8 vid_which_vrm(void)
{
printk(KERN_INFO "hwmon-vid: Unknown VRM version of your CPU\n");
return 0;
}
#endif
EXPORT_SYMBOL(vid_from_reg);
EXPORT_SYMBOL(vid_which_vrm);
MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
MODULE_DESCRIPTION("hwmon-vid driver");
MODULE_LICENSE("GPL");