drivers/wlan/third_party/atheros/ath10k/spectral.c

/*
 * Copyright (c) 2013 Qualcomm Atheros, Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <linux/relay.h>

#include "core.h"
#include "debug.h"
#include "wmi-ops.h"

static void send_fft_sample(struct ath10k* ar, const struct fft_sample_tlv* fft_sample_tlv) {
    int length;

    if (!ar->spectral.rfs_chan_spec_scan) { return; }

    length = __be16_to_cpu(fft_sample_tlv->length) + sizeof(*fft_sample_tlv);
    relay_write(ar->spectral.rfs_chan_spec_scan, fft_sample_tlv, length);
}

static uint8_t get_max_exp(int8_t max_index, uint16_t max_magnitude, size_t bin_len,
                           uint8_t* data) {
    int dc_pos;
    uint8_t max_exp;

    dc_pos = bin_len / 2;

    /* peak index outside of bins */
    if (dc_pos < max_index || -dc_pos >= max_index) { return 0; }

    for (max_exp = 0; max_exp < 8; max_exp++) {
        if (data[dc_pos + max_index] == (max_magnitude >> max_exp)) { break; }
    }

    /* max_exp not found */
    if (data[dc_pos + max_index] != (max_magnitude >> max_exp)) { return 0; }

    return max_exp;
}

static inline size_t ath10k_spectral_fix_bin_size(struct ath10k* ar, size_t bin_len) {
    /* some chipsets reports bin size as 2^n bytes + 'm' bytes in
     * report mode 2. First 2^n bytes carries inband tones and last
     * 'm' bytes carries band edge detection data mainly used in
     * radar detection purpose. Strip last 'm' bytes to make bin size
     * as a valid one. 'm' can take possible values of 4, 12.
     */
    if (!IS_POW2(bin_len)) { bin_len -= ar->hw_params.spectral_bin_discard; }

    return bin_len;
}

int ath10k_spectral_process_fft(struct ath10k* ar, struct wmi_phyerr_ev_arg* phyerr,
                                const struct phyerr_fft_report* fftr, size_t bin_len,
                                uint64_t tsf) {
    struct fft_sample_ath10k* fft_sample;
    uint8_t buf[sizeof(*fft_sample) + SPECTRAL_ATH10K_MAX_NUM_BINS];
    uint16_t freq1, freq2, total_gain_db, base_pwr_db, length, peak_mag;
    uint32_t reg0, reg1;
    uint8_t chain_idx, *bins;
    int dc_pos;

    fft_sample = (struct fft_sample_ath10k*)&buf;

    bin_len = ath10k_spectral_fix_bin_size(ar, bin_len);

    if (bin_len < 64 || bin_len > SPECTRAL_ATH10K_MAX_NUM_BINS) { return -EINVAL; }

    reg0 = fftr->reg0;
    reg1 = fftr->reg1;

    length = sizeof(*fft_sample) - sizeof(struct fft_sample_tlv) + bin_len;
    fft_sample->tlv.type = ATH_FFT_SAMPLE_ATH10K;
    fft_sample->tlv.length = __cpu_to_be16(length);

    /* TODO: there might be a reason why the hardware reports 20/40/80 MHz,
     * but the results/plots suggest that its actually 22/44/88 MHz.
     */
    switch (phyerr->chan_width_mhz) {
    case 20:
        fft_sample->chan_width_mhz = 22;
        break;
    case 40:
        fft_sample->chan_width_mhz = 44;
        break;
    case 80:
        /* TODO: As experiments with an analogue sender and various
         * configurations (fft-sizes of 64/128/256 and 20/40/80 Mhz)
         * show, the particular configuration of 80 MHz/64 bins does
         * not match with the other samples at all. Until the reason
         * for that is found, don't report these samples.
         */
        if (bin_len == 64) { return -EINVAL; }
        fft_sample->chan_width_mhz = 88;
        break;
    default:
        fft_sample->chan_width_mhz = phyerr->chan_width_mhz;
    }

    fft_sample->relpwr_db = MS(reg1, SEARCH_FFT_REPORT_REG1_RELPWR_DB);
    fft_sample->avgpwr_db = MS(reg1, SEARCH_FFT_REPORT_REG1_AVGPWR_DB);

    peak_mag = MS(reg1, SEARCH_FFT_REPORT_REG1_PEAK_MAG);
    fft_sample->max_magnitude = __cpu_to_be16(peak_mag);
    fft_sample->max_index = MS(reg0, SEARCH_FFT_REPORT_REG0_PEAK_SIDX);
    fft_sample->rssi = phyerr->rssi_combined;

    total_gain_db = MS(reg0, SEARCH_FFT_REPORT_REG0_TOTAL_GAIN_DB);
    base_pwr_db = MS(reg0, SEARCH_FFT_REPORT_REG0_BASE_PWR_DB);
    fft_sample->total_gain_db = __cpu_to_be16(total_gain_db);
    fft_sample->base_pwr_db = __cpu_to_be16(base_pwr_db);

    freq1 = phyerr->freq1;
    freq2 = phyerr->freq2;
    fft_sample->freq1 = __cpu_to_be16(freq1);
    fft_sample->freq2 = __cpu_to_be16(freq2);

    chain_idx = MS(reg0, SEARCH_FFT_REPORT_REG0_FFT_CHN_IDX);

    fft_sample->noise = __cpu_to_be16(phyerr->nf_chains[chain_idx]);

    bins = (uint8_t*)fftr;
    bins += sizeof(*fftr);

    fft_sample->tsf = __cpu_to_be64(tsf);

    /* max_exp has been directly reported by previous hardware (ath9k),
     * maybe its possible to get it by other means?
     */
    fft_sample->max_exp = get_max_exp(fft_sample->max_index, peak_mag, bin_len, bins);

    memcpy(fft_sample->data, bins, bin_len);

    /* DC value (value in the middle) is the blind spot of the spectral
     * sample and invalid, interpolate it.
     */
    dc_pos = bin_len / 2;
    fft_sample->data[dc_pos] = (fft_sample->data[dc_pos + 1] + fft_sample->data[dc_pos - 1]) / 2;

    send_fft_sample(ar, &fft_sample->tlv);

    return 0;
}

static struct ath10k_vif* ath10k_get_spectral_vdev(struct ath10k* ar) {
    struct ath10k_vif* arvif;

    ASSERT_MTX_HELD(&ar->conf_mutex);

    if (list_empty(&ar->arvifs)) { return NULL; }

    /* if there already is a vif doing spectral, return that. */
    list_for_each_entry(arvif, &ar->arvifs, list) if (arvif->spectral_enabled) { return arvif; }

    /* otherwise, return the first vif. */
    return list_first_entry(&ar->arvifs, typeof(*arvif), list);
}

static int ath10k_spectral_scan_trigger(struct ath10k* ar) {
    struct ath10k_vif* arvif;
    int res;
    int vdev_id;

    ASSERT_MTX_HELD(&ar->conf_mutex);

    arvif = ath10k_get_spectral_vdev(ar);
    if (!arvif) { return -ENODEV; }
    vdev_id = arvif->vdev_id;

    if (ar->spectral.mode == SPECTRAL_DISABLED) { return 0; }

    res = ath10k_wmi_vdev_spectral_enable(ar, vdev_id, WMI_SPECTRAL_TRIGGER_CMD_CLEAR,
                                          WMI_SPECTRAL_ENABLE_CMD_ENABLE);
    if (res < 0) { return res; }

    res = ath10k_wmi_vdev_spectral_enable(ar, vdev_id, WMI_SPECTRAL_TRIGGER_CMD_TRIGGER,
                                          WMI_SPECTRAL_ENABLE_CMD_ENABLE);
    if (res < 0) { return res; }

    return 0;
}

static int ath10k_spectral_scan_config(struct ath10k* ar, enum ath10k_spectral_mode mode) {
    struct wmi_vdev_spectral_conf_arg arg;
    struct ath10k_vif* arvif;
    int vdev_id, count, res = 0;

    ASSERT_MTX_HELD(&ar->conf_mutex);

    arvif = ath10k_get_spectral_vdev(ar);
    if (!arvif) { return -ENODEV; }

    vdev_id = arvif->vdev_id;

    arvif->spectral_enabled = (mode != SPECTRAL_DISABLED);
    ar->spectral.mode = mode;

    res = ath10k_wmi_vdev_spectral_enable(ar, vdev_id, WMI_SPECTRAL_TRIGGER_CMD_CLEAR,
                                          WMI_SPECTRAL_ENABLE_CMD_DISABLE);
    if (res < 0) {
        ath10k_warn("failed to enable spectral scan: %d\n", res);
        return res;
    }

    if (mode == SPECTRAL_DISABLED) { return 0; }

    if (mode == SPECTRAL_BACKGROUND) {
        count = WMI_SPECTRAL_COUNT_DEFAULT;
    } else {
        count = max_t(uint8_t, 1, ar->spectral.config.count);
    }

    arg.vdev_id = vdev_id;
    arg.scan_count = count;
    arg.scan_period = WMI_SPECTRAL_PERIOD_DEFAULT;
    arg.scan_priority = WMI_SPECTRAL_PRIORITY_DEFAULT;
    arg.scan_fft_size = ar->spectral.config.fft_size;
    arg.scan_gc_ena = WMI_SPECTRAL_GC_ENA_DEFAULT;
    arg.scan_restart_ena = WMI_SPECTRAL_RESTART_ENA_DEFAULT;
    arg.scan_noise_floor_ref = WMI_SPECTRAL_NOISE_FLOOR_REF_DEFAULT;
    arg.scan_init_delay = WMI_SPECTRAL_INIT_DELAY_DEFAULT;
    arg.scan_nb_tone_thr = WMI_SPECTRAL_NB_TONE_THR_DEFAULT;
    arg.scan_str_bin_thr = WMI_SPECTRAL_STR_BIN_THR_DEFAULT;
    arg.scan_wb_rpt_mode = WMI_SPECTRAL_WB_RPT_MODE_DEFAULT;
    arg.scan_rssi_rpt_mode = WMI_SPECTRAL_RSSI_RPT_MODE_DEFAULT;
    arg.scan_rssi_thr = WMI_SPECTRAL_RSSI_THR_DEFAULT;
    arg.scan_pwr_format = WMI_SPECTRAL_PWR_FORMAT_DEFAULT;
    arg.scan_rpt_mode = WMI_SPECTRAL_RPT_MODE_DEFAULT;
    arg.scan_bin_scale = WMI_SPECTRAL_BIN_SCALE_DEFAULT;
    arg.scan_dbm_adj = WMI_SPECTRAL_DBM_ADJ_DEFAULT;
    arg.scan_chn_mask = WMI_SPECTRAL_CHN_MASK_DEFAULT;

    res = ath10k_wmi_vdev_spectral_conf(ar, &arg);
    if (res < 0) {
        ath10k_warn("failed to configure spectral scan: %d\n", res);
        return res;
    }

    return 0;
}

static ssize_t read_file_spec_scan_ctl(struct file* file, char __user* user_buf, size_t count,
                                       loff_t* ppos) {
    struct ath10k* ar = file->private_data;
    char* mode = "";
    size_t len;
    enum ath10k_spectral_mode spectral_mode;

    mtx_lock(&ar->conf_mutex);
    spectral_mode = ar->spectral.mode;
    mtx_unlock(&ar->conf_mutex);

    switch (spectral_mode) {
    case SPECTRAL_DISABLED:
        mode = "disable";
        break;
    case SPECTRAL_BACKGROUND:
        mode = "background";
        break;
    case SPECTRAL_MANUAL:
        mode = "manual";
        break;
    }

    len = strlen(mode);
    return simple_read_from_buffer(user_buf, count, ppos, mode, len);
}

static ssize_t write_file_spec_scan_ctl(struct file* file, const char __user* user_buf,
                                        size_t count, loff_t* ppos) {
    struct ath10k* ar = file->private_data;
    char buf[32];
    ssize_t len;
    int res;

    len = MIN(count, sizeof(buf) - 1);
    if (copy_from_user(buf, user_buf, len)) { return -EFAULT; }

    buf[len] = '\0';

    mtx_lock(&ar->conf_mutex);

    if (strncmp("trigger", buf, 7) == 0) {
        if (ar->spectral.mode == SPECTRAL_MANUAL || ar->spectral.mode == SPECTRAL_BACKGROUND) {
            /* reset the configuration to adopt possibly changed
             * debugfs parameters
             */
            res = ath10k_spectral_scan_config(ar, ar->spectral.mode);
            if (res < 0) { ath10k_warn("failed to reconfigure spectral scan: %d\n", res); }
            res = ath10k_spectral_scan_trigger(ar);
            if (res < 0) { ath10k_warn("failed to trigger spectral scan: %d\n", res); }
        } else {
            res = -EINVAL;
        }
    } else if (strncmp("background", buf, 10) == 0) {
        res = ath10k_spectral_scan_config(ar, SPECTRAL_BACKGROUND);
    } else if (strncmp("manual", buf, 6) == 0) {
        res = ath10k_spectral_scan_config(ar, SPECTRAL_MANUAL);
    } else if (strncmp("disable", buf, 7) == 0) {
        res = ath10k_spectral_scan_config(ar, SPECTRAL_DISABLED);
    } else {
        res = -EINVAL;
    }

    mtx_unlock(&ar->conf_mutex);

    if (res < 0) { return res; }

    return count;
}

static const struct file_operations fops_spec_scan_ctl = {
    .read = read_file_spec_scan_ctl,
    .write = write_file_spec_scan_ctl,
    .open = simple_open,
    .owner = THIS_MODULE,
    .llseek = default_llseek,
};

static ssize_t read_file_spectral_count(struct file* file, char __user* user_buf, size_t count,
                                        loff_t* ppos) {
    struct ath10k* ar = file->private_data;
    char buf[32];
    size_t len;
    uint8_t spectral_count;

    mtx_lock(&ar->conf_mutex);
    spectral_count = ar->spectral.config.count;
    mtx_unlock(&ar->conf_mutex);

    len = sprintf(buf, "%d\n", spectral_count);
    return simple_read_from_buffer(user_buf, count, ppos, buf, len);
}

static ssize_t write_file_spectral_count(struct file* file, const char __user* user_buf,
                                         size_t count, loff_t* ppos) {
    struct ath10k* ar = file->private_data;
    unsigned long val;
    char buf[32];
    ssize_t len;

    len = MIN(count, sizeof(buf) - 1);
    if (copy_from_user(buf, user_buf, len)) { return -EFAULT; }

    buf[len] = '\0';
    if (kstrtoul(buf, 0, &val)) { return -EINVAL; }

    if (val < 0 || val > 255) { return -EINVAL; }

    mtx_lock(&ar->conf_mutex);
    ar->spectral.config.count = val;
    mtx_unlock(&ar->conf_mutex);

    return count;
}

static const struct file_operations fops_spectral_count = {
    .read = read_file_spectral_count,
    .write = write_file_spectral_count,
    .open = simple_open,
    .owner = THIS_MODULE,
    .llseek = default_llseek,
};

static ssize_t read_file_spectral_bins(struct file* file, char __user* user_buf, size_t count,
                                       loff_t* ppos) {
    struct ath10k* ar = file->private_data;
    char buf[32];
    unsigned int bins, fft_size, bin_scale;
    size_t len;

    mtx_lock(&ar->conf_mutex);

    fft_size = ar->spectral.config.fft_size;
    bin_scale = WMI_SPECTRAL_BIN_SCALE_DEFAULT;
    bins = 1 << (fft_size - bin_scale);

    mtx_unlock(&ar->conf_mutex);

    len = sprintf(buf, "%d\n", bins);
    return simple_read_from_buffer(user_buf, count, ppos, buf, len);
}

static ssize_t write_file_spectral_bins(struct file* file, const char __user* user_buf,
                                        size_t count, loff_t* ppos) {
    struct ath10k* ar = file->private_data;
    unsigned long val;
    char buf[32];
    ssize_t len;

    len = MIN(count, sizeof(buf) - 1);
    if (copy_from_user(buf, user_buf, len)) { return -EFAULT; }

    buf[len] = '\0';
    if (kstrtoul(buf, 0, &val)) { return -EINVAL; }

    if (val < 64 || val > SPECTRAL_ATH10K_MAX_NUM_BINS) { return -EINVAL; }

    if (!IS_POW2(val)) { return -EINVAL; }

    mtx_lock(&ar->conf_mutex);
    ar->spectral.config.fft_size = LOG2(val);
    ar->spectral.config.fft_size += WMI_SPECTRAL_BIN_SCALE_DEFAULT;
    mtx_unlock(&ar->conf_mutex);

    return count;
}

static const struct file_operations fops_spectral_bins = {
    .read = read_file_spectral_bins,
    .write = write_file_spectral_bins,
    .open = simple_open,
    .owner = THIS_MODULE,
    .llseek = default_llseek,
};

static struct dentry* create_buf_file_handler(const char* filename, struct dentry* parent,
                                              umode_t mode, struct rchan_buf* buf, int* is_global) {
    struct dentry* buf_file;

    buf_file = debugfs_create_file(filename, mode, parent, buf, &relay_file_operations);
    *is_global = 1;
    return buf_file;
}

static int remove_buf_file_handler(struct dentry* dentry) {
    debugfs_remove(dentry);

    return 0;
}

static struct rchan_callbacks rfs_spec_scan_cb = {
    .create_buf_file = create_buf_file_handler,
    .remove_buf_file = remove_buf_file_handler,
};

int ath10k_spectral_start(struct ath10k* ar) {
    struct ath10k_vif* arvif;

    ASSERT_MTX_HELD(&ar->conf_mutex);

    list_for_each_entry(arvif, &ar->arvifs, list) arvif->spectral_enabled = 0;

    ar->spectral.mode = SPECTRAL_DISABLED;
    ar->spectral.config.count = WMI_SPECTRAL_COUNT_DEFAULT;
    ar->spectral.config.fft_size = WMI_SPECTRAL_FFT_SIZE_DEFAULT;

    return 0;
}

int ath10k_spectral_vif_stop(struct ath10k_vif* arvif) {
    if (!arvif->spectral_enabled) { return 0; }

    return ath10k_spectral_scan_config(arvif->ar, SPECTRAL_DISABLED);
}

int ath10k_spectral_create(struct ath10k* ar) {
    /* The buffer size covers whole channels in dual bands up to 128 bins.
     * Scan with bigger than 128 bins needs to be run on single band each.
     */
    ar->spectral.rfs_chan_spec_scan =
        relay_open("spectral_scan", ar->debug.debugfs_phy, 1140, 2500, &rfs_spec_scan_cb, NULL);
    debugfs_create_file("spectral_scan_ctl", 0600, ar->debug.debugfs_phy, ar, &fops_spec_scan_ctl);
    debugfs_create_file("spectral_count", 0600, ar->debug.debugfs_phy, ar, &fops_spectral_count);
    debugfs_create_file("spectral_bins", 0600, ar->debug.debugfs_phy, ar, &fops_spectral_bins);

    return 0;
}

void ath10k_spectral_destroy(struct ath10k* ar) {
    if (ar->spectral.rfs_chan_spec_scan) {
        relay_close(ar->spectral.rfs_chan_spec_scan);
        ar->spectral.rfs_chan_spec_scan = NULL;
    }
}