src/soc/intel/common/block/cse/telemetry.c

/* SPDX-License-Identifier: GPL-2.0-or-later */

#include <console/console.h>
#include <intelblocks/cse.h>
#include <timestamp.h>

#define MSEC_TO_USEC(x) (x * 1000)

static void cbmem_inject_telemetry_data(void)
{
	struct cse_boot_perf_rsp cse_perf_data;
	s64 ts[NUM_CSE_BOOT_PERF_DATA] = {0};
	s64 current_time, start_stamp;
	int zero_point_idx = 0;

	/*
	 * 1. Each TS holds the time elapsed between the "Zero-Point" till the TS itself
	 *    happened.
	 * 2. In case CSME did not hit some of the TS in the latest boot flow that value of
	 *    these TS will be 0x00000000.
	 * 3. In case of error, TS value will be set to 0xFFFFFFFF.
	 * 4. All other TS values will be relative to the zero point. The API caller should
	 *    normalize the TS values to the zero-point value.
	 */
	if (!cse_get_boot_performance_data(&cse_perf_data))
		return;

	current_time = timestamp_get();

	for (unsigned int i = 0; i < NUM_CSE_BOOT_PERF_DATA; i++) {

		if (cse_perf_data.timestamp[i] == 0xffffffff) {
			printk(BIOS_ERR, "%s: CSME timestamps invalid\n", __func__);
			return;
		}

		ts[i] = (s64)MSEC_TO_USEC(cse_perf_data.timestamp[i]) *
							timestamp_tick_freq_mhz();
	}

	/* Find zero-point */
	for (unsigned int i = 0; i < NUM_CSE_BOOT_PERF_DATA; i++) {
		if (cse_perf_data.timestamp[i] != 0) {
			zero_point_idx = i;
			break;
		}
	}

	/* Normalize TS values to zero-point */
	for (unsigned int i = zero_point_idx + 1; i < NUM_CSE_BOOT_PERF_DATA; i++) {

		if (ts[i] && ts[i] < ts[zero_point_idx]) {
			printk(BIOS_ERR, "%s: CSME timestamps invalid,"
					" wraparound detected\n", __func__);
			return;
		}

		if (ts[i])
			ts[i] -= ts[zero_point_idx];
	}

	/* Inject CSME timestamps into the coreboot timestamp table */
	start_stamp = current_time - ts[PERF_DATA_CSME_GET_PERF_RESPONSE];

	timestamp_add(TS_ME_ROM_START, start_stamp);
	timestamp_add(TS_ME_BOOT_STALL_END,
		start_stamp + ts[PERF_DATA_CSME_RBE_BOOT_STALL_DONE_TO_PMC]);
	timestamp_add(TS_ME_ICC_CONFIG_START,
		start_stamp + ts[PERF_DATA_CSME_POLL_FOR_PMC_PPS_START]);
	timestamp_add(TS_ME_HOST_BOOT_PREP_END,
		start_stamp + ts[PERF_DATA_CSME_HOST_BOOT_PREP_DONE]);
	timestamp_add(TS_ME_RECEIVED_CRDA_FROM_PMC,
		start_stamp + ts[PERF_DATA_PMC_SENT_CRDA]);
}

void cse_get_telemetry_data(void)
{
	/* If CSE is already hidden then accessing CSE registers should be avoided */
	if (!is_cse_enabled()) {
		printk(BIOS_DEBUG, "CSE is disabled, not sending `Get Boot Perf` message\n");
		return;
	}

	cbmem_inject_telemetry_data();
}