diff options
Diffstat (limited to 'drivers/crypto/intel/qat/qat_common/adf_clock.c')
| -rw-r--r-- | drivers/crypto/intel/qat/qat_common/adf_clock.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/crypto/intel/qat/qat_common/adf_clock.c b/drivers/crypto/intel/qat/qat_common/adf_clock.c new file mode 100644 index 000000000000..dc0778691eb0 --- /dev/null +++ b/drivers/crypto/intel/qat/qat_common/adf_clock.c @@ -0,0 +1,131 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2023 Intel Corporation */ + +#include <linux/delay.h> +#include <linux/dev_printk.h> +#include <linux/export.h> +#include <linux/math.h> +#include <linux/minmax.h> +#include <linux/time64.h> +#include <linux/types.h> +#include <linux/units.h> +#include <asm/errno.h> +#include "adf_accel_devices.h" +#include "adf_clock.h" +#include "adf_common_drv.h" + +#define MEASURE_CLOCK_RETRIES 10 +#define MEASURE_CLOCK_DELAY_US 10000 +#define ME_CLK_DIVIDER 16 +#define MEASURE_CLOCK_DELTA_THRESHOLD_US 100 + +static inline u64 timespec_to_us(const struct timespec64 *ts) +{ + return (u64)DIV_ROUND_CLOSEST_ULL(timespec64_to_ns(ts), NSEC_PER_USEC); +} + +static inline u64 timespec_to_ms(const struct timespec64 *ts) +{ + return (u64)DIV_ROUND_CLOSEST_ULL(timespec64_to_ns(ts), NSEC_PER_MSEC); +} + +u64 adf_clock_get_current_time(void) +{ + struct timespec64 ts; + + ktime_get_real_ts64(&ts); + return timespec_to_ms(&ts); +} + +static int measure_clock(struct adf_accel_dev *accel_dev, u32 *frequency) +{ + struct timespec64 ts1, ts2, ts3, ts4; + u64 timestamp1, timestamp2, temp; + u32 delta_us, tries; + int ret; + + tries = MEASURE_CLOCK_RETRIES; + do { + ktime_get_real_ts64(&ts1); + ret = adf_get_fw_timestamp(accel_dev, ×tamp1); + if (ret) { + dev_err(&GET_DEV(accel_dev), + "Failed to get fw timestamp\n"); + return ret; + } + ktime_get_real_ts64(&ts2); + delta_us = timespec_to_us(&ts2) - timespec_to_us(&ts1); + } while (delta_us > MEASURE_CLOCK_DELTA_THRESHOLD_US && --tries); + + if (!tries) { + dev_err(&GET_DEV(accel_dev), "Excessive clock measure delay\n"); + return -ETIMEDOUT; + } + + fsleep(MEASURE_CLOCK_DELAY_US); + + tries = MEASURE_CLOCK_RETRIES; + do { + ktime_get_real_ts64(&ts3); + if (adf_get_fw_timestamp(accel_dev, ×tamp2)) { + dev_err(&GET_DEV(accel_dev), + "Failed to get fw timestamp\n"); + return -EIO; + } + ktime_get_real_ts64(&ts4); + delta_us = timespec_to_us(&ts4) - timespec_to_us(&ts3); + } while (delta_us > MEASURE_CLOCK_DELTA_THRESHOLD_US && --tries); + + if (!tries) { + dev_err(&GET_DEV(accel_dev), "Excessive clock measure delay\n"); + return -ETIMEDOUT; + } + + delta_us = timespec_to_us(&ts3) - timespec_to_us(&ts1); + temp = (timestamp2 - timestamp1) * ME_CLK_DIVIDER * 10; + temp = DIV_ROUND_CLOSEST_ULL(temp, delta_us); + /* + * Enclose the division to allow the preprocessor to precalculate it, + * and avoid promoting r-value to 64-bit before division. + */ + *frequency = temp * (HZ_PER_MHZ / 10); + + return 0; +} + +/** + * adf_dev_measure_clock() - measures device clock frequency + * @accel_dev: Pointer to acceleration device. + * @frequency: Pointer to variable where result will be stored + * @min: Minimal allowed frequency value + * @max: Maximal allowed frequency value + * + * If the measurement result will go beyond the min/max thresholds the value + * will take the value of the crossed threshold. + * + * This algorithm compares the device firmware timestamp with the kernel + * timestamp. So we can't expect too high accuracy from this measurement. + * + * Return: + * * 0 - measurement succeed + * * -ETIMEDOUT - measurement failed + */ +int adf_dev_measure_clock(struct adf_accel_dev *accel_dev, + u32 *frequency, u32 min, u32 max) +{ + int ret; + u32 freq; + + ret = measure_clock(accel_dev, &freq); + if (ret) + return ret; + + *frequency = clamp(freq, min, max); + + if (*frequency != freq) + dev_warn(&GET_DEV(accel_dev), + "Measured clock %d Hz is out of range, assuming %d\n", + freq, *frequency); + return 0; +} +EXPORT_SYMBOL_GPL(adf_dev_measure_clock); |