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-rw-r--r--include/linux/hwmon-vid.h112
1 files changed, 112 insertions, 0 deletions
diff --git a/include/linux/hwmon-vid.h b/include/linux/hwmon-vid.h
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+++ b/include/linux/hwmon-vid.h
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+/*
+ hwmon-vid.h - VID/VRM/VRD voltage conversions
+
+ Originally part of lm_sensors
+ 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.
+*/
+
+/*
+ This file contains common code for decoding VID pins.
+ This file is #included in various chip drivers in this directory.
+ As the user is unlikely to load more than one driver which
+ includes this code we don't worry about the wasted space.
+ Reference: VRM x.y DC-DC Converter Design Guidelines,
+ available at http://developer.intel.com
+*/
+
+/*
+ AMD Opteron processors don't follow the Intel VRM spec.
+ I'm going to "make up" 2.4 as the VRM spec for the Opterons.
+ No good reason just a mnemonic for the 24x Opteron processor
+ series
+
+ Opteron VID encoding is:
+
+ 00000 = 1.550 V
+ 00001 = 1.525 V
+ . . . .
+ 11110 = 0.800 V
+ 11111 = 0.000 V (off)
+ */
+
+/*
+ Legal val values 0x00 - 0x1f; except for VRD 10.0, 0x00 - 0x3f.
+ vrm is the Intel VRM document version.
+ Note: vrm version is scaled by 10 and the return value is scaled by 1000
+ to avoid floating point in the kernel.
+*/
+
+int vid_which_vrm(void);
+
+#define DEFAULT_VRM 82
+
+static inline int vid_from_reg(int val, int vrm)
+{
+ int vid;
+
+ switch(vrm) {
+
+ case 0:
+ return 0;
+
+ case 100: /* VRD 10.0 */
+ if((val & 0x1f) == 0x1f)
+ return 0;
+ if((val & 0x1f) <= 0x09 || val == 0x0a)
+ vid = 10875 - (val & 0x1f) * 250;
+ else
+ vid = 18625 - (val & 0x1f) * 250;
+ if(val & 0x20)
+ vid -= 125;
+ vid /= 10; /* only return 3 dec. places for now */
+ return vid;
+
+ case 24: /* Opteron processor */
+ return(val == 0x1f ? 0 : 1550 - val * 25);
+
+ case 91: /* VRM 9.1 */
+ case 90: /* VRM 9.0 */
+ return(val == 0x1f ? 0 :
+ 1850 - val * 25);
+
+ case 85: /* VRM 8.5 */
+ return((val & 0x10 ? 25 : 0) +
+ ((val & 0x0f) > 0x04 ? 2050 : 1250) -
+ ((val & 0x0f) * 50));
+
+ case 84: /* VRM 8.4 */
+ val &= 0x0f;
+ /* fall through */
+ default: /* VRM 8.2 */
+ return(val == 0x1f ? 0 :
+ val & 0x10 ? 5100 - (val) * 100 :
+ 2050 - (val) * 50);
+ }
+}
+
+static inline int vid_to_reg(int val, int vrm)
+{
+ switch (vrm) {
+ case 91: /* VRM 9.1 */
+ case 90: /* VRM 9.0 */
+ return ((val >= 1100) && (val <= 1850) ?
+ ((18499 - val * 10) / 25 + 5) / 10 : -1);
+ default:
+ return -1;
+ }
+}