/*
 * Copyright (c) 2019, NVIDIA CORPORATION. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <arch.h>
#include <arch_helpers.h>
#include <common/debug.h>
#include <denver.h>
#include <lib/mmio.h>
#include <mce_private.h>
#include <errno.h>

extern void nvg_set_request_data(uint64_t req, uint64_t data);
extern void nvg_set_request(uint64_t req);
extern uint64_t nvg_get_result(void);

int nvg_enter_cstate(uint32_t ari_base, uint32_t state, uint32_t wake_time)
{
	/* check for allowed power state */
	if (state != TEGRA_ARI_CORE_C0 && state != TEGRA_ARI_CORE_C1 &&
	    state != TEGRA_ARI_CORE_C6 && state != TEGRA_ARI_CORE_C7) {
		ERROR("%s: unknown cstate (%d)\n", __func__, state);
		return EINVAL;
	}

	/* time (TSC ticks) until the core is expected to get a wake event */
	nvg_set_request_data(TEGRA_NVG_CHANNEL_WAKE_TIME, wake_time);

	/* set the core cstate */
	write_actlr_el1(state);

	return 0;
}

/*
 * This request allows updating of CLUSTER_CSTATE, CCPLEX_CSTATE and
 * SYSTEM_CSTATE values.
 */
int nvg_update_cstate_info(uint32_t ari_base, uint32_t cluster, uint32_t ccplex,
		uint32_t system, uint8_t sys_state_force, uint32_t wake_mask,
		uint8_t update_wake_mask)
{
	uint64_t val = 0;

	/* update CLUSTER_CSTATE? */
	if (cluster)
		val |= (cluster & CLUSTER_CSTATE_MASK) |
			CLUSTER_CSTATE_UPDATE_BIT;

	/* update CCPLEX_CSTATE? */
	if (ccplex)
		val |= (ccplex & CCPLEX_CSTATE_MASK) << CCPLEX_CSTATE_SHIFT |
			CCPLEX_CSTATE_UPDATE_BIT;

	/* update SYSTEM_CSTATE? */
	if (system)
		val |= ((system & SYSTEM_CSTATE_MASK) << SYSTEM_CSTATE_SHIFT) |
		       ((sys_state_force << SYSTEM_CSTATE_FORCE_UPDATE_SHIFT) |
			SYSTEM_CSTATE_UPDATE_BIT);

	/* update wake mask value? */
	if (update_wake_mask)
		val |= CSTATE_WAKE_MASK_UPDATE_BIT;

	/* set the wake mask */
	val &= CSTATE_WAKE_MASK_CLEAR;
	val |= ((uint64_t)wake_mask << CSTATE_WAKE_MASK_SHIFT);

	/* set the updated cstate info */
	nvg_set_request_data(TEGRA_NVG_CHANNEL_CSTATE_INFO, val);

	return 0;
}

int nvg_update_crossover_time(uint32_t ari_base, uint32_t type, uint32_t time)
{
	/* sanity check crossover type */
	if (type > TEGRA_ARI_CROSSOVER_CCP3_SC1)
		return EINVAL;

	/*
	 * The crossover threshold limit types start from
	 * TEGRA_CROSSOVER_TYPE_C1_C6 to TEGRA_CROSSOVER_TYPE_CCP3_SC7. The
	 * command indices for updating the threshold can be generated
	 * by adding the type to the NVG_SET_THRESHOLD_CROSSOVER_C1_C6
	 * command index.
	 */
	nvg_set_request_data(TEGRA_NVG_CHANNEL_CROSSOVER_C1_C6 + type,
		(uint64_t)time);

	return 0;
}

uint64_t nvg_read_cstate_stats(uint32_t ari_base, uint32_t state)
{
	/* sanity check state */
	if (state == 0)
		return EINVAL;

	/*
	 * The cstate types start from NVG_READ_CSTATE_STATS_SC7_ENTRIES
	 * to NVG_GET_LAST_CSTATE_ENTRY_A57_3. The command indices for
	 * reading the threshold can be generated by adding the type to
	 * the NVG_CLEAR_CSTATE_STATS command index.
	 */
	nvg_set_request(TEGRA_NVG_CHANNEL_CSTATE_STATS_CLEAR + state);

	return (int64_t)nvg_get_result();
}

int nvg_write_cstate_stats(uint32_t ari_base, uint32_t state, uint32_t stats)
{
	uint64_t val;

	/*
	 * The only difference between a CSTATE_STATS_WRITE and
	 * CSTATE_STATS_READ is the usage of the 63:32 in the request.
	 * 63:32 are set to '0' for a read, while a write contains the
	 * actual stats value to be written.
	 */
	val = ((uint64_t)stats << MCE_CSTATE_STATS_TYPE_SHIFT) | state;

	/*
	 * The cstate types start from NVG_READ_CSTATE_STATS_SC7_ENTRIES
	 * to NVG_GET_LAST_CSTATE_ENTRY_A57_3. The command indices for
	 * reading the threshold can be generated by adding the type to
	 * the NVG_CLEAR_CSTATE_STATS command index.
	 */
	nvg_set_request_data(TEGRA_NVG_CHANNEL_CSTATE_STATS_CLEAR + state, val);

	return 0;
}

int nvg_is_ccx_allowed(uint32_t ari_base, uint32_t state, uint32_t wake_time)
{
	/* This does not apply to the Denver cluster */
	return 0;
}

int nvg_is_sc7_allowed(uint32_t ari_base, uint32_t state, uint32_t wake_time)
{
	uint64_t val;

	/* check for allowed power state */
	if (state != TEGRA_ARI_CORE_C0 && state != TEGRA_ARI_CORE_C1 &&
	    state != TEGRA_ARI_CORE_C6 && state != TEGRA_ARI_CORE_C7) {
		ERROR("%s: unknown cstate (%d)\n", __func__, state);
		return EINVAL;
	}

	/*
	 * Request format -
	 * 63:32 = wake time
	 * 31:0 = C-state for this core
	 */
	val = ((uint64_t)wake_time << MCE_SC7_WAKE_TIME_SHIFT) |
			(state & MCE_SC7_ALLOWED_MASK);

	/* issue command to check if SC7 is allowed */
	nvg_set_request_data(TEGRA_NVG_CHANNEL_IS_SC7_ALLOWED, val);

	/* 1 = SC7 allowed, 0 = SC7 not allowed */
	return !!nvg_get_result();
}

int nvg_online_core(uint32_t ari_base, uint32_t core)
{
	int cpu = read_mpidr() & MPIDR_CPU_MASK;
	int impl = (read_midr() >> MIDR_IMPL_SHIFT) & MIDR_IMPL_MASK;

	/* sanity check code id */
	if ((core >= MCE_CORE_ID_MAX) || (cpu == core)) {
		ERROR("%s: unsupported core id (%d)\n", __func__, core);
		return EINVAL;
	}

	/*
	 * The Denver cluster has 2 CPUs only - 0, 1.
	 */
	if (impl == DENVER_IMPL && ((core == 2) || (core == 3))) {
		ERROR("%s: unknown core id (%d)\n", __func__, core);
		return EINVAL;
	}

	/* get a core online */
	nvg_set_request_data(TEGRA_NVG_CHANNEL_ONLINE_CORE, core & MCE_CORE_ID_MASK);

	return 0;
}

int nvg_cc3_ctrl(uint32_t ari_base, uint32_t freq, uint32_t volt, uint8_t enable)
{
	int val;

	/*
	 * If the enable bit is cleared, Auto-CC3 will be disabled by setting
	 * the SW visible voltage/frequency request registers for all non
	 * floorswept cores valid independent of StandbyWFI and disabling
	 * the IDLE voltage/frequency request register. If set, Auto-CC3
	 * will be enabled by setting the ARM SW visible voltage/frequency
	 * request registers for all non floorswept cores to be enabled by
	 * StandbyWFI or the equivalent signal, and always keeping the IDLE
	 * voltage/frequency request register enabled.
	 */
	val = (((freq & MCE_AUTO_CC3_FREQ_MASK) << MCE_AUTO_CC3_FREQ_SHIFT) |\
		((volt & MCE_AUTO_CC3_VTG_MASK) << MCE_AUTO_CC3_VTG_SHIFT) |\
		(enable ? MCE_AUTO_CC3_ENABLE_BIT : 0));

	nvg_set_request_data(TEGRA_NVG_CHANNEL_CC3_CTRL, val);

	return 0;
}
