--- /dev/null
+/*
+ * 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#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://support.amd.com/us/Processor_TechDocs/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 26: /* AMD family 10h to 15h, serial VID */
+ val &= 0x7f;
+ if (val >= 0x7c)
+ return 0;
+ return DIV_ROUND_CLOSEST(15500 - 125 * val, 10);
+
+ 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:
+ case 131:
+ val &= 0x3f;
+ /* Exception for Eden ULV 500 MHz */
+ if (vrm == 131 && val == 0x3f)
+ val++;
+ 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)
+ pr_warn("Requested unsupported VRM version (%u)\n",
+ (unsigned int)vrm);
+ return 0;
+ }
+}
+EXPORT_SYMBOL(vid_from_reg);
+
+/*
+ * 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 family;
+ u8 model_from;
+ u8 model_to;
+ u8 stepping_to;
+ u8 vrm_type;
+};
+
+#define ANY 0xFF
+
+#ifdef CONFIG_X86
+
+/*
+ * The stepping_to 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, 0x0, ANY, ANY, 90}, /* Athlon Duron etc */
+ {X86_VENDOR_AMD, 0xF, 0x0, 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, 0x40, 0x7F, ANY, 24}, /* NPT family 0Fh */
+ {X86_VENDOR_AMD, 0xF, 0x80, ANY, ANY, 25}, /* future fam. 0Fh */
+ {X86_VENDOR_AMD, 0x10, 0x0, ANY, ANY, 25}, /* NPT family 10h */
+ {X86_VENDOR_AMD, 0x11, 0x0, ANY, ANY, 26}, /* family 11h */
+ {X86_VENDOR_AMD, 0x12, 0x0, ANY, ANY, 26}, /* family 12h */
+ {X86_VENDOR_AMD, 0x14, 0x0, ANY, ANY, 26}, /* family 14h */
+ {X86_VENDOR_AMD, 0x15, 0x0, ANY, ANY, 26}, /* family 15h */
+
+ {X86_VENDOR_INTEL, 0x6, 0x0, 0x6, ANY, 82}, /* Pentium Pro,
+ * Pentium II, Xeon,
+ * Mobile Pentium,
+ * Celeron */
+ {X86_VENDOR_INTEL, 0x6, 0x7, 0x7, ANY, 84}, /* Pentium III, Xeon */
+ {X86_VENDOR_INTEL, 0x6, 0x8, 0x8, ANY, 82}, /* Pentium III, Xeon */
+ {X86_VENDOR_INTEL, 0x6, 0x9, 0x9, ANY, 13}, /* Pentium M (130 nm) */
+ {X86_VENDOR_INTEL, 0x6, 0xA, 0xA, ANY, 82}, /* Pentium III Xeon */
+ {X86_VENDOR_INTEL, 0x6, 0xB, 0xB, ANY, 85}, /* Tualatin */
+ {X86_VENDOR_INTEL, 0x6, 0xD, 0xD, ANY, 13}, /* Pentium M (90 nm) */
+ {X86_VENDOR_INTEL, 0x6, 0xE, 0xE, ANY, 14}, /* Intel Core (65 nm) */
+ {X86_VENDOR_INTEL, 0x6, 0xF, ANY, ANY, 110}, /* Intel Conroe and
+ * later */
+ {X86_VENDOR_INTEL, 0xF, 0x0, 0x0, ANY, 90}, /* P4 */
+ {X86_VENDOR_INTEL, 0xF, 0x1, 0x1, ANY, 90}, /* P4 Willamette */
+ {X86_VENDOR_INTEL, 0xF, 0x2, 0x2, ANY, 90}, /* P4 Northwood */
+ {X86_VENDOR_INTEL, 0xF, 0x3, ANY, ANY, 100}, /* Prescott and above
+ * assume VRD 10 */
+
+ {X86_VENDOR_CENTAUR, 0x6, 0x7, 0x7, ANY, 85}, /* Eden ESP/Ezra */
+ {X86_VENDOR_CENTAUR, 0x6, 0x8, 0x8, 0x7, 85}, /* Ezra T */
+ {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, 0x7, 85}, /* Nehemiah */
+ {X86_VENDOR_CENTAUR, 0x6, 0x9, 0x9, ANY, 17}, /* C3-M, Eden-N */
+ {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, 0x7, 0}, /* No information */
+ {X86_VENDOR_CENTAUR, 0x6, 0xA, 0xA, ANY, 13}, /* C7-M, C7,
+ * Eden (Esther) */
+ {X86_VENDOR_CENTAUR, 0x6, 0xD, 0xD, ANY, 134}, /* C7-D, C7-M, C7,
+ * Eden (Esther) */
+};
+
+/*
+ * Special case for VIA model D: there are two different possible
+ * VID tables, so we have to figure out first, which one must be
+ * used. This resolves temporary drm value 134 to 14 (Intel Core
+ * 7-bit VID), 13 (Pentium M 6-bit VID) or 131 (Pentium M 6-bit VID
+ * + quirk for Eden ULV 500 MHz).
+ * Note: something similar might be needed for model A, I'm not sure.
+ */
+static u8 get_via_model_d_vrm(void)
+{
+ unsigned int vid, brand, __maybe_unused dummy;
+ static const char *brands[4] = {
+ "C7-M", "C7", "Eden", "C7-D"
+ };
+
+ rdmsr(0x198, dummy, vid);
+ vid &= 0xff;
+
+ rdmsr(0x1154, brand, dummy);
+ brand = ((brand >> 4) ^ (brand >> 2)) & 0x03;
+
+ if (vid > 0x3f) {
+ pr_info("Using %d-bit VID table for VIA %s CPU\n",
+ 7, brands[brand]);
+ return 14;
+ } else {
+ pr_info("Using %d-bit VID table for VIA %s CPU\n",
+ 6, brands[brand]);
+ /* Enable quirk for Eden */
+ return brand == 2 ? 131 : 13;
+ }
+}
+
+static u8 find_vrm(u8 family, u8 model, u8 stepping, u8 vendor)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(vrm_models); i++) {
+ if (vendor == vrm_models[i].vendor &&
+ family == vrm_models[i].family &&
+ model >= vrm_models[i].model_from &&
+ model <= vrm_models[i].model_to &&
+ stepping <= vrm_models[i].stepping_to)
+ return vrm_models[i].vrm_type;
+ }
+
+ return 0;
+}
+
+u8 vid_which_vrm(void)
+{
+ struct cpuinfo_x86 *c = &cpu_data(0);
+ u8 vrm_ret;
+
+ if (c->x86 < 6) /* Any CPU with family lower than 6 */
+ return 0; /* doesn't have VID */
+
+ vrm_ret = find_vrm(c->x86, c->x86_model, c->x86_mask, c->x86_vendor);
+ if (vrm_ret == 134)
+ vrm_ret = get_via_model_d_vrm();
+ if (vrm_ret == 0)
+ pr_info("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)
+{
+ pr_info("Unknown VRM version of your CPU\n");
+ return 0;
+}
+#endif
+EXPORT_SYMBOL(vid_which_vrm);
+
+MODULE_AUTHOR("Rudolf Marek <r.marek@assembler.cz>");
+
+MODULE_DESCRIPTION("hwmon-vid driver");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff