1 files changed, 189 insertions, 0 deletions

diff --git a/drivers/hwmon/hwmon-vid.c b/drivers/hwmon/hwmon-vid.c
new file mode 100644
index 000000000000..312769ad4dab
--- /dev/null
+++ b/drivers/hwmon/hwmon-vid.c
@@ -0,0 +1,189 @@
+/*
+    hwmon-vid.c - VID/VRM/VRD voltage conversions
+
+    Copyright (c) 2004 Rudolf Marek <r.marek@sh.cvut.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/config.h>
+#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 Opteron processors don't follow the Intel specifications.
+    I'm going to "make up" 2.4 as the spec number 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)
+*/
+
+/* vrm is the VRM/VRD document version multiplied by 10.
+   val is the 4-, 5- or 6-bit VID code.
+   Returned value is in mV to avoid floating point in the kernel. */
+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);
+        }
+}
+
+
+/*
+    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;
+        int vrm_type;
+};
+
+#define ANY 0xFF
+
+#ifdef CONFIG_X86
+
+static struct vrm_model vrm_models[] = {
+        {X86_VENDOR_AMD, 0x6, ANY, 90},         /* Athlon Duron etc */
+        {X86_VENDOR_AMD, 0xF, ANY, 24},         /* Athlon 64, Opteron */
+        {X86_VENDOR_INTEL, 0x6, 0x9, 85},       /* 0.13um too */
+        {X86_VENDOR_INTEL, 0x6, 0xB, 85},       /* Tualatin */
+        {X86_VENDOR_INTEL, 0x6, ANY, 82},       /* any P6 */
+        {X86_VENDOR_INTEL, 0x7, ANY, 0},        /* Itanium */
+        {X86_VENDOR_INTEL, 0xF, 0x0, 90},       /* P4 */
+        {X86_VENDOR_INTEL, 0xF, 0x1, 90},       /* P4 Willamette */
+        {X86_VENDOR_INTEL, 0xF, 0x2, 90},       /* P4 Northwood */
+        {X86_VENDOR_INTEL, 0xF, 0x3, 100},      /* P4 Prescott */
+        {X86_VENDOR_INTEL, 0xF, 0x4, 100},      /* P4 Prescott */
+        {X86_VENDOR_INTEL, 0x10,ANY, 0},        /* Itanium 2 */
+        {X86_VENDOR_UNKNOWN, ANY, ANY, 0}       /* stop here */
+};
+
+static int find_vrm(u8 eff_family, u8 eff_model, 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==ANY)))
+                                return vrm_models[i].vrm_type;
+                i++;
+        }
+
+        return 0;
+}
+
+int vid_which_vrm(void)
+{
+        struct cpuinfo_x86 *c = cpu_data;
+        u32 eax;
+        u8 eff_family, eff_model;
+        int 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);
+        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,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 something completely different for the non-x86 world */
+#else
+int 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@sh.cvut.cz>");
+
+MODULE_DESCRIPTION("hwmon-vid driver");
+MODULE_LICENSE("GPL");