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Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/platforms/cell/cbe_thermal.c | 386 |
1 files changed, 386 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/cell/cbe_thermal.c b/arch/powerpc/platforms/cell/cbe_thermal.c new file mode 100644 index 000000000..2f45428e3 --- /dev/null +++ b/arch/powerpc/platforms/cell/cbe_thermal.c @@ -0,0 +1,386 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * thermal support for the cell processor + * + * This module adds some sysfs attributes to cpu and spu nodes. + * Base for measurements are the digital thermal sensors (DTS) + * located on the chip. + * The accuracy is 2 degrees, starting from 65 up to 125 degrees celsius + * The attributes can be found under + * /sys/devices/system/cpu/cpuX/thermal + * /sys/devices/system/spu/spuX/thermal + * + * The following attributes are added for each node: + * temperature: + * contains the current temperature measured by the DTS + * throttle_begin: + * throttling begins when temperature is greater or equal to + * throttle_begin. Setting this value to 125 prevents throttling. + * throttle_end: + * throttling is being ceased, if the temperature is lower than + * throttle_end. Due to a delay between applying throttling and + * a reduced temperature this value should be less than throttle_begin. + * A value equal to throttle_begin provides only a very little hysteresis. + * throttle_full_stop: + * If the temperatrue is greater or equal to throttle_full_stop, + * full throttling is applied to the cpu or spu. This value should be + * greater than throttle_begin and throttle_end. Setting this value to + * 65 prevents the unit from running code at all. + * + * (C) Copyright IBM Deutschland Entwicklung GmbH 2005 + * + * Author: Christian Krafft <krafft@de.ibm.com> + */ + +#include <linux/module.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/cpu.h> +#include <linux/stringify.h> +#include <asm/spu.h> +#include <asm/io.h> +#include <asm/cell-regs.h> + +#include "spu_priv1_mmio.h" + +#define TEMP_MIN 65 +#define TEMP_MAX 125 + +#define DEVICE_PREFIX_ATTR(_prefix,_name,_mode) \ +struct device_attribute attr_ ## _prefix ## _ ## _name = { \ + .attr = { .name = __stringify(_name), .mode = _mode }, \ + .show = _prefix ## _show_ ## _name, \ + .store = _prefix ## _store_ ## _name, \ +}; + +static inline u8 reg_to_temp(u8 reg_value) +{ + return ((reg_value & 0x3f) << 1) + TEMP_MIN; +} + +static inline u8 temp_to_reg(u8 temp) +{ + return ((temp - TEMP_MIN) >> 1) & 0x3f; +} + +static struct cbe_pmd_regs __iomem *get_pmd_regs(struct device *dev) +{ + struct spu *spu; + + spu = container_of(dev, struct spu, dev); + + return cbe_get_pmd_regs(spu_devnode(spu)); +} + +/* returns the value for a given spu in a given register */ +static u8 spu_read_register_value(struct device *dev, union spe_reg __iomem *reg) +{ + union spe_reg value; + struct spu *spu; + + spu = container_of(dev, struct spu, dev); + value.val = in_be64(®->val); + + return value.spe[spu->spe_id]; +} + +static ssize_t spu_show_temp(struct device *dev, struct device_attribute *attr, + char *buf) +{ + u8 value; + struct cbe_pmd_regs __iomem *pmd_regs; + + pmd_regs = get_pmd_regs(dev); + + value = spu_read_register_value(dev, &pmd_regs->ts_ctsr1); + + return sprintf(buf, "%d\n", reg_to_temp(value)); +} + +static ssize_t show_throttle(struct cbe_pmd_regs __iomem *pmd_regs, char *buf, int pos) +{ + u64 value; + + value = in_be64(&pmd_regs->tm_tpr.val); + /* access the corresponding byte */ + value >>= pos; + value &= 0x3F; + + return sprintf(buf, "%d\n", reg_to_temp(value)); +} + +static ssize_t store_throttle(struct cbe_pmd_regs __iomem *pmd_regs, const char *buf, size_t size, int pos) +{ + u64 reg_value; + unsigned int temp; + u64 new_value; + int ret; + + ret = sscanf(buf, "%u", &temp); + + if (ret != 1 || temp < TEMP_MIN || temp > TEMP_MAX) + return -EINVAL; + + new_value = temp_to_reg(temp); + + reg_value = in_be64(&pmd_regs->tm_tpr.val); + + /* zero out bits for new value */ + reg_value &= ~(0xffull << pos); + /* set bits to new value */ + reg_value |= new_value << pos; + + out_be64(&pmd_regs->tm_tpr.val, reg_value); + return size; +} + +static ssize_t spu_show_throttle_end(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return show_throttle(get_pmd_regs(dev), buf, 0); +} + +static ssize_t spu_show_throttle_begin(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return show_throttle(get_pmd_regs(dev), buf, 8); +} + +static ssize_t spu_show_throttle_full_stop(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return show_throttle(get_pmd_regs(dev), buf, 16); +} + +static ssize_t spu_store_throttle_end(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return store_throttle(get_pmd_regs(dev), buf, size, 0); +} + +static ssize_t spu_store_throttle_begin(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return store_throttle(get_pmd_regs(dev), buf, size, 8); +} + +static ssize_t spu_store_throttle_full_stop(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return store_throttle(get_pmd_regs(dev), buf, size, 16); +} + +static ssize_t ppe_show_temp(struct device *dev, char *buf, int pos) +{ + struct cbe_pmd_regs __iomem *pmd_regs; + u64 value; + + pmd_regs = cbe_get_cpu_pmd_regs(dev->id); + value = in_be64(&pmd_regs->ts_ctsr2); + + value = (value >> pos) & 0x3f; + + return sprintf(buf, "%d\n", reg_to_temp(value)); +} + + +/* shows the temperature of the DTS on the PPE, + * located near the linear thermal sensor */ +static ssize_t ppe_show_temp0(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return ppe_show_temp(dev, buf, 32); +} + +/* shows the temperature of the second DTS on the PPE */ +static ssize_t ppe_show_temp1(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return ppe_show_temp(dev, buf, 0); +} + +static ssize_t ppe_show_throttle_end(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return show_throttle(cbe_get_cpu_pmd_regs(dev->id), buf, 32); +} + +static ssize_t ppe_show_throttle_begin(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return show_throttle(cbe_get_cpu_pmd_regs(dev->id), buf, 40); +} + +static ssize_t ppe_show_throttle_full_stop(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return show_throttle(cbe_get_cpu_pmd_regs(dev->id), buf, 48); +} + +static ssize_t ppe_store_throttle_end(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return store_throttle(cbe_get_cpu_pmd_regs(dev->id), buf, size, 32); +} + +static ssize_t ppe_store_throttle_begin(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return store_throttle(cbe_get_cpu_pmd_regs(dev->id), buf, size, 40); +} + +static ssize_t ppe_store_throttle_full_stop(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + return store_throttle(cbe_get_cpu_pmd_regs(dev->id), buf, size, 48); +} + + +static struct device_attribute attr_spu_temperature = { + .attr = {.name = "temperature", .mode = 0400 }, + .show = spu_show_temp, +}; + +static DEVICE_PREFIX_ATTR(spu, throttle_end, 0600); +static DEVICE_PREFIX_ATTR(spu, throttle_begin, 0600); +static DEVICE_PREFIX_ATTR(spu, throttle_full_stop, 0600); + + +static struct attribute *spu_attributes[] = { + &attr_spu_temperature.attr, + &attr_spu_throttle_end.attr, + &attr_spu_throttle_begin.attr, + &attr_spu_throttle_full_stop.attr, + NULL, +}; + +static const struct attribute_group spu_attribute_group = { + .name = "thermal", + .attrs = spu_attributes, +}; + +static struct device_attribute attr_ppe_temperature0 = { + .attr = {.name = "temperature0", .mode = 0400 }, + .show = ppe_show_temp0, +}; + +static struct device_attribute attr_ppe_temperature1 = { + .attr = {.name = "temperature1", .mode = 0400 }, + .show = ppe_show_temp1, +}; + +static DEVICE_PREFIX_ATTR(ppe, throttle_end, 0600); +static DEVICE_PREFIX_ATTR(ppe, throttle_begin, 0600); +static DEVICE_PREFIX_ATTR(ppe, throttle_full_stop, 0600); + +static struct attribute *ppe_attributes[] = { + &attr_ppe_temperature0.attr, + &attr_ppe_temperature1.attr, + &attr_ppe_throttle_end.attr, + &attr_ppe_throttle_begin.attr, + &attr_ppe_throttle_full_stop.attr, + NULL, +}; + +static struct attribute_group ppe_attribute_group = { + .name = "thermal", + .attrs = ppe_attributes, +}; + +/* + * initialize throttling with default values + */ +static int __init init_default_values(void) +{ + int cpu; + struct cbe_pmd_regs __iomem *pmd_regs; + struct device *dev; + union ppe_spe_reg tpr; + union spe_reg str1; + u64 str2; + union spe_reg cr1; + u64 cr2; + + /* TPR defaults */ + /* ppe + * 1F - no full stop + * 08 - dynamic throttling starts if over 80 degrees + * 03 - dynamic throttling ceases if below 70 degrees */ + tpr.ppe = 0x1F0803; + /* spe + * 10 - full stopped when over 96 degrees + * 08 - dynamic throttling starts if over 80 degrees + * 03 - dynamic throttling ceases if below 70 degrees + */ + tpr.spe = 0x100803; + + /* STR defaults */ + /* str1 + * 10 - stop 16 of 32 cycles + */ + str1.val = 0x1010101010101010ull; + /* str2 + * 10 - stop 16 of 32 cycles + */ + str2 = 0x10; + + /* CR defaults */ + /* cr1 + * 4 - normal operation + */ + cr1.val = 0x0404040404040404ull; + /* cr2 + * 4 - normal operation + */ + cr2 = 0x04; + + for_each_possible_cpu (cpu) { + pr_debug("processing cpu %d\n", cpu); + dev = get_cpu_device(cpu); + + if (!dev) { + pr_info("invalid dev pointer for cbe_thermal\n"); + return -EINVAL; + } + + pmd_regs = cbe_get_cpu_pmd_regs(dev->id); + + if (!pmd_regs) { + pr_info("invalid CBE regs pointer for cbe_thermal\n"); + return -EINVAL; + } + + out_be64(&pmd_regs->tm_str2, str2); + out_be64(&pmd_regs->tm_str1.val, str1.val); + out_be64(&pmd_regs->tm_tpr.val, tpr.val); + out_be64(&pmd_regs->tm_cr1.val, cr1.val); + out_be64(&pmd_regs->tm_cr2, cr2); + } + + return 0; +} + + +static int __init thermal_init(void) +{ + int rc = init_default_values(); + + if (rc == 0) { + spu_add_dev_attr_group(&spu_attribute_group); + cpu_add_dev_attr_group(&ppe_attribute_group); + } + + return rc; +} +module_init(thermal_init); + +static void __exit thermal_exit(void) +{ + spu_remove_dev_attr_group(&spu_attribute_group); + cpu_remove_dev_attr_group(&ppe_attribute_group); +} +module_exit(thermal_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Christian Krafft <krafft@de.ibm.com>"); + |