diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c b/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c index f76b6cf8040e..73a8b46e0234 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_sysfs_pm.c @@ -14,6 +14,7 @@ #include "intel_gt_regs.h" #include "intel_gt_sysfs.h" #include "intel_gt_sysfs_pm.h" +#include "intel_pcode.h" #include "intel_rc6.h" #include "intel_rps.h" @@ -558,6 +559,174 @@ static const struct attribute *freq_attrs[] = { NULL }; +/* + * Scaling for multipliers (aka frequency factors). + * The format of the value in the register is u8.8. + * + * The presentation to userspace is inspired by the perf event framework. + * See: + * Documentation/ABI/testing/sysfs-bus-event_source-devices-events + * for description of: + * /sys/bus/event_source/devices/<pmu>/events/<event>.scale + * + * Summary: Expose two sysfs files for each multiplier. + * + * 1. File <attr> contains a raw hardware value. + * 2. File <attr>.scale contains the multiplicative scale factor to be + * used by userspace to compute the actual value. + * + * So userspace knows that to get the frequency_factor it multiplies the + * provided value by the specified scale factor and vice-versa. + * + * That way there is no precision loss in the kernel interface and API + * is future proof should one day the hardware register change to u16.u16, + * on some platform. (Or any other fixed point representation.) + * + * Example: + * File <attr> contains the value 2.5, represented as u8.8 0x0280, which + * is comprised of: + * - an integer part of 2 + * - a fractional part of 0x80 (representing 0x80 / 2^8 == 0x80 / 256). + * File <attr>.scale contains a string representation of floating point + * value 0.00390625 (which is (1 / 256)). + * Userspace computes the actual value: + * 0x0280 * 0.00390625 -> 2.5 + * or converts an actual value to the value to be written into <attr>: + * 2.5 / 0.00390625 -> 0x0280 + */ + +#define U8_8_VAL_MASK 0xffff +#define U8_8_SCALE_TO_VALUE "0.00390625" + +static ssize_t freq_factor_scale_show(struct device *dev, + struct device_attribute *attr, + char *buff) +{ + return sysfs_emit(buff, "%s\n", U8_8_SCALE_TO_VALUE); +} + +static u32 media_ratio_mode_to_factor(u32 mode) +{ + /* 0 -> 0, 1 -> 256, 2 -> 128 */ + return !mode ? mode : 256 / mode; +} + +static ssize_t media_freq_factor_show(struct device *dev, + struct device_attribute *attr, + char *buff) +{ + struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name); + struct intel_guc_slpc *slpc = >->uc.guc.slpc; + intel_wakeref_t wakeref; + u32 mode; + + /* + * Retrieve media_ratio_mode from GEN6_RPNSWREQ bit 13 set by + * GuC. GEN6_RPNSWREQ:13 value 0 represents 1:2 and 1 represents 1:1 + */ + if (IS_XEHPSDV(gt->i915) && + slpc->media_ratio_mode == SLPC_MEDIA_RATIO_MODE_DYNAMIC_CONTROL) { + /* + * For XEHPSDV dynamic mode GEN6_RPNSWREQ:13 does not contain + * the media_ratio_mode, just return the cached media ratio + */ + mode = slpc->media_ratio_mode; + } else { + with_intel_runtime_pm(gt->uncore->rpm, wakeref) + mode = intel_uncore_read(gt->uncore, GEN6_RPNSWREQ); + mode = REG_FIELD_GET(GEN12_MEDIA_FREQ_RATIO, mode) ? + SLPC_MEDIA_RATIO_MODE_FIXED_ONE_TO_ONE : + SLPC_MEDIA_RATIO_MODE_FIXED_ONE_TO_TWO; + } + + return sysfs_emit(buff, "%u\n", media_ratio_mode_to_factor(mode)); +} + +static ssize_t media_freq_factor_store(struct device *dev, + struct device_attribute *attr, + const char *buff, size_t count) +{ + struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name); + struct intel_guc_slpc *slpc = >->uc.guc.slpc; + u32 factor, mode; + int err; + + err = kstrtou32(buff, 0, &factor); + if (err) + return err; + + for (mode = SLPC_MEDIA_RATIO_MODE_DYNAMIC_CONTROL; + mode <= SLPC_MEDIA_RATIO_MODE_FIXED_ONE_TO_TWO; mode++) + if (factor == media_ratio_mode_to_factor(mode)) + break; + + if (mode > SLPC_MEDIA_RATIO_MODE_FIXED_ONE_TO_TWO) + return -EINVAL; + + err = intel_guc_slpc_set_media_ratio_mode(slpc, mode); + if (!err) { + slpc->media_ratio_mode = mode; + DRM_DEBUG("Set slpc->media_ratio_mode to %d", mode); + } + return err ?: count; +} + +static ssize_t media_RP0_freq_mhz_show(struct device *dev, + struct device_attribute *attr, + char *buff) +{ + struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name); + u32 val; + int err; + + err = snb_pcode_read_p(gt->uncore, XEHP_PCODE_FREQUENCY_CONFIG, + PCODE_MBOX_FC_SC_READ_FUSED_P0, + PCODE_MBOX_DOMAIN_MEDIAFF, &val); + + if (err) + return err; + + /* Fused media RP0 read from pcode is in units of 50 MHz */ + val *= GT_FREQUENCY_MULTIPLIER; + + return sysfs_emit(buff, "%u\n", val); +} + +static ssize_t media_RPn_freq_mhz_show(struct device *dev, + struct device_attribute *attr, + char *buff) +{ + struct intel_gt *gt = intel_gt_sysfs_get_drvdata(dev, attr->attr.name); + u32 val; + int err; + + err = snb_pcode_read_p(gt->uncore, XEHP_PCODE_FREQUENCY_CONFIG, + PCODE_MBOX_FC_SC_READ_FUSED_PN, + PCODE_MBOX_DOMAIN_MEDIAFF, &val); + + if (err) + return err; + + /* Fused media RPn read from pcode is in units of 50 MHz */ + val *= GT_FREQUENCY_MULTIPLIER; + + return sysfs_emit(buff, "%u\n", val); +} + +static DEVICE_ATTR_RW(media_freq_factor); +static struct device_attribute dev_attr_media_freq_factor_scale = + __ATTR(media_freq_factor.scale, 0444, freq_factor_scale_show, NULL); +static DEVICE_ATTR_RO(media_RP0_freq_mhz); +static DEVICE_ATTR_RO(media_RPn_freq_mhz); + +static const struct attribute *media_perf_power_attrs[] = { + &dev_attr_media_freq_factor.attr, + &dev_attr_media_freq_factor_scale.attr, + &dev_attr_media_RP0_freq_mhz.attr, + &dev_attr_media_RPn_freq_mhz.attr, + NULL +}; + static int intel_sysfs_rps_init(struct intel_gt *gt, struct kobject *kobj, const struct attribute * const *attrs) { @@ -599,4 +768,12 @@ void intel_gt_sysfs_pm_init(struct intel_gt *gt, struct kobject *kobj) drm_warn(>->i915->drm, "failed to create gt%u throttle sysfs files (%pe)", gt->info.id, ERR_PTR(ret)); + + if (HAS_MEDIA_RATIO_MODE(gt->i915) && intel_uc_uses_guc_slpc(>->uc)) { + ret = sysfs_create_files(kobj, media_perf_power_attrs); + if (ret) + drm_warn(>->i915->drm, + "failed to create gt%u media_perf_power_attrs sysfs (%pe)\n", + gt->info.id, ERR_PTR(ret)); + } } |