From 60eb0b35a9cc3400251cb4028d100e350649cf8a Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Fri, 24 Nov 2006 11:47:08 -0200 Subject: [PATCH] ACPI: ibm-acpi: Implement direct-ec-access thermal reading modes for up to 16 sensors This patch extends ibm-acpi to support reading thermal sensors directly through ACPI EC register access. It uses a DMI match to detect ThinkPads with a new-style embedded controller, that are known to have forward- compatible register maps and use 0x00 to fill in non-used registers and export thermal sensors at EC offsets 0x78-7F and 0xC0-C7. Direct ACPI EC register access is implemented for 8-sensor and 16-sensor new-style ThinkPad controller firmwares as an experimental feature. The code does some limited sanity checks on the temperatures read through EC access, and will default to the old ACPI TMP0-7 mode if anything is amiss. Userspace ABI is not changed for 8 sensors, but /proc/acpi/ibm/thermal is extended for 16 sensors if the firmware supports 16 sensors. A documentation update is also provided. The information about the ThinkPad register map was determined by studying ibm-acpi "ecdump" output from various ThinkPad models, submitted by subscribers of the linux-thinkpad mailinglist. Futher information was gathered from the DSDT tables, as they describe the EC register map in recent ThinkPads. DSDT source shows that TMP0-7 access and direct register access are actually the same thing on these firmwares, but unfortunately IBM never did update their DSDT EC register map to export TMP8-TMP15 for the second range of sensors. Signed-off-by: Henrique de Moraes Holschuh --- Documentation/ibm-acpi.txt | 55 +++++++++++++++++----- drivers/acpi/ibm_acpi.c | 93 +++++++++++++++++++++++++++++++++++++- 2 files changed, 134 insertions(+), 14 deletions(-) diff --git a/Documentation/ibm-acpi.txt b/Documentation/ibm-acpi.txt index e50595bfd8..30f09e7a42 100644 --- a/Documentation/ibm-acpi.txt +++ b/Documentation/ibm-acpi.txt @@ -398,25 +398,56 @@ Temperature sensors -- /proc/acpi/ibm/thermal Most ThinkPads include six or more separate temperature sensors but only expose the CPU temperature through the standard ACPI methods. -This feature shows readings from up to eight different sensors. Some -readings may not be valid, e.g. may show large negative values. For -example, on the X40, a typical output may be: +This feature shows readings from up to eight different sensors on older +ThinkPads, and it has experimental support for up to sixteen different +sensors on newer ThinkPads. Readings from sensors that are not available +return -128. +No commands can be written to this file. + +EXPERIMENTAL: The 16-sensors feature is marked EXPERIMENTAL because the +implementation directly accesses hardware registers and may not work as +expected. USE WITH CAUTION! To use this feature, you need to supply the +experimental=1 parameter when loading the module. When EXPERIMENTAL +mode is enabled, reading the first 8 sensors on newer ThinkPads will +also use an new experimental thermal sensor access mode. + +For example, on the X40, a typical output may be: temperatures: 42 42 45 41 36 -128 33 -128 -Thomas Gruber took his R51 apart and traced all six active sensors in -his laptop (the location of sensors may vary on other models): +EXPERIMENTAL: On the T43/p, a typical output may be: +temperatures: 48 48 36 52 38 -128 31 -128 48 52 48 -128 -128 -128 -128 -128 + +The mapping of thermal sensors to physical locations varies depending on +system-board model (and thus, on ThinkPad model). + +http://thinkwiki.org/wiki/Thermal_Sensors is a public wiki page that +tries to track down these locations for various models. + +Most (newer?) models seem to follow this pattern: 1: CPU -2: Mini PCI Module -3: HDD +2: (depends on model) +3: (depends on model) 4: GPU -5: Battery -6: N/A -7: Battery -8: N/A +5: Main battery: main sensor +6: Bay battery: main sensor +7: Main battery: secondary sensor +8: Bay battery: secondary sensor +9-15: (depends on model) + +For the R51 (source: Thomas Gruber): +2: Mini-PCI +3: Internal HDD + +For the T43, T43/p (source: Shmidoax/Thinkwiki.org) +http://thinkwiki.org/wiki/Thermal_Sensors#ThinkPad_T43.2C_T43p +2: System board, left side (near PCMCIA slot), reported as HDAPS temp +3: PCMCIA slot +9: MCH (northbridge) to DRAM Bus +10: ICH (southbridge), under Mini-PCI card, under touchpad +11: Power regulator, underside of system board, below F2 key -No commands can be written to this file. EXPERIMENTAL: Embedded controller register dump -- /proc/acpi/ibm/ecdump ------------------------------------------------------------------------ diff --git a/drivers/acpi/ibm_acpi.c b/drivers/acpi/ibm_acpi.c index baf9492f0a..1703c617c0 100644 --- a/drivers/acpi/ibm_acpi.c +++ b/drivers/acpi/ibm_acpi.c @@ -80,6 +80,7 @@ #include #include #include +#include #include #include @@ -221,13 +222,17 @@ enum thermal_access_mode { IBMACPI_THERMAL_NONE = 0, /* No thermal support */ IBMACPI_THERMAL_ACPI_TMP07, /* Use ACPI TMP0-7 */ IBMACPI_THERMAL_ACPI_UPDT, /* Use ACPI TMP0-7 with UPDT */ + IBMACPI_THERMAL_TPEC_8, /* Use ACPI EC regs, 8 sensors */ + IBMACPI_THERMAL_TPEC_16, /* Use ACPI EC regs, 16 sensors */ }; -#define IBMACPI_MAX_THERMAL_SENSORS 8 /* Max thermal sensors supported */ +#define IBMACPI_MAX_THERMAL_SENSORS 16 /* Max thermal sensors supported */ struct ibm_thermal_sensors_struct { s32 temp[IBMACPI_MAX_THERMAL_SENSORS]; }; +static int ibm_thinkpad_ec_found; + struct ibm_struct { char *name; char param[32]; @@ -1290,7 +1295,52 @@ static enum thermal_access_mode thermal_read_mode; static int thermal_init(void) { - if (acpi_evalf(ec_handle, NULL, "TMP7", "qv")) { + u8 t, ta1, ta2; + int i; + int acpi_tmp7 = acpi_evalf(ec_handle, NULL, "TMP7", "qv"); + + if (ibm_thinkpad_ec_found && experimental) { + /* + * Direct EC access mode: sensors at registers + * 0x78-0x7F, 0xC0-0xC7. Registers return 0x00 for + * non-implemented, thermal sensors return 0x80 when + * not available + */ + + ta1 = ta2 = 0; + for (i = 0; i < 8; i++) { + if (likely(acpi_ec_read(0x78 + i, &t))) { + ta1 |= t; + } else { + ta1 = 0; + break; + } + if (likely(acpi_ec_read(0xC0 + i, &t))) { + ta2 |= t; + } else { + ta1 = 0; + break; + } + } + if (ta1 == 0) { + /* This is sheer paranoia, but we handle it anyway */ + if (acpi_tmp7) { + printk(IBM_ERR + "ThinkPad ACPI EC access misbehaving, " + "falling back to ACPI TMPx access mode\n"); + thermal_read_mode = IBMACPI_THERMAL_ACPI_TMP07; + } else { + printk(IBM_ERR + "ThinkPad ACPI EC access misbehaving, " + "disabling thermal sensors access\n"); + thermal_read_mode = IBMACPI_THERMAL_NONE; + } + } else { + thermal_read_mode = + (ta2 != 0) ? + IBMACPI_THERMAL_TPEC_16 : IBMACPI_THERMAL_TPEC_8; + } + } else if (acpi_tmp7) { if (acpi_evalf(ec_handle, NULL, "UPDT", "qv")) { /* 600e/x, 770e, 770x */ thermal_read_mode = IBMACPI_THERMAL_ACPI_UPDT; @@ -1309,12 +1359,30 @@ static int thermal_init(void) static int thermal_get_sensors(struct ibm_thermal_sensors_struct *s) { int i, t; + s8 tmp; char tmpi[] = "TMPi"; if (!s) return -EINVAL; switch (thermal_read_mode) { +#if IBMACPI_MAX_THERMAL_SENSORS >= 16 + case IBMACPI_THERMAL_TPEC_16: + for (i = 0; i < 8; i++) { + if (!acpi_ec_read(0xC0 + i, &tmp)) + return -EIO; + s->temp[i + 8] = tmp * 1000; + } + /* fallthrough */ +#endif + case IBMACPI_THERMAL_TPEC_8: + for (i = 0; i < 8; i++) { + if (!acpi_ec_read(0x78 + i, &tmp)) + return -EIO; + s->temp[i] = tmp * 1000; + } + return (thermal_read_mode == IBMACPI_THERMAL_TPEC_16) ? 16 : 8; + case IBMACPI_THERMAL_ACPI_UPDT: if (!acpi_evalf(ec_handle, NULL, "UPDT", "v")) return -EIO; @@ -2052,6 +2120,24 @@ static void acpi_ibm_exit(void) remove_proc_entry(IBM_DIR, acpi_root_dir); } +static int __init check_dmi_for_ec(void) +{ + struct dmi_device *dev = NULL; + + /* + * ThinkPad T23 or newer, A31 or newer, R50e or newer, + * X32 or newer, all Z series; Some models must have an + * up-to-date BIOS or they will not be detected. + * + * See http://thinkwiki.org/wiki/List_of_DMI_IDs + */ + while ((dev = dmi_find_device(DMI_DEV_TYPE_OEM_STRING, NULL, dev))) { + if (strstr(dev->name, "IBM ThinkPad Embedded Controller")) + return 1; + } + return 0; +} + static int __init acpi_ibm_init(void) { int ret, i; @@ -2071,6 +2157,9 @@ static int __init acpi_ibm_init(void) return -ENODEV; } + /* Models with newer firmware report the EC in DMI */ + ibm_thinkpad_ec_found = check_dmi_for_ec(); + /* these handles are not required */ IBM_HANDLE_INIT(vid); IBM_HANDLE_INIT(vid2); -- 2.20.1