/*
 * Copyright (c) 2018-2019, ARM Limited and Contributors. All rights reserved.
 * Copyright (c) 2018-2022, Xilinx, Inc. All rights reserved.
 * Copyright (C) 2022, Advanced Micro Devices, Inc. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <common/debug.h>
#include <common/interrupt_props.h>
#include <drivers/arm/gicv3.h>
#include <lib/utils.h>
#include <plat/common/platform.h>

#include <plat_private.h>
#include <platform_def.h>

/******************************************************************************
 * The following functions are defined as weak to allow a platform to override
 * the way the GICv3 driver is initialised and used.
 *****************************************************************************/
#pragma weak plat_versal_net_gic_driver_init
#pragma weak plat_versal_net_gic_init
#pragma weak plat_versal_net_gic_cpuif_enable
#pragma weak plat_versal_net_gic_cpuif_disable
#pragma weak plat_versal_net_gic_pcpu_init
#pragma weak plat_versal_net_gic_redistif_on
#pragma weak plat_versal_net_gic_redistif_off

/* The GICv3 driver only needs to be initialized in EL3 */
static uintptr_t rdistif_base_addrs[PLATFORM_CORE_COUNT];

static const uintptr_t gicr_base_addrs[2] = {
	PLAT_VERSAL_NET_GICR_BASE,	/* GICR Base address of the primary CPU */
	0U				/* Zero Termination */
};

/* List of zero terminated GICR frame addresses which CPUs will probe */
static const uintptr_t *gicr_frames;

static const interrupt_prop_t versal_net_interrupt_props[] = {
	PLAT_VERSAL_NET_G1S_IRQ_PROPS(INTR_GROUP1S),
	PLAT_VERSAL_NET_G0_IRQ_PROPS(INTR_GROUP0)
};

/*
 * We save and restore the GICv3 context on system suspend. Allocate the
 * data in the designated EL3 Secure carve-out memory.
 */
static gicv3_redist_ctx_t rdist_ctx __section("versal_net_el3_tzc_dram");
static gicv3_dist_ctx_t dist_ctx __section("versal_net_el3_tzc_dram");

/*
 * MPIDR hashing function for translating MPIDRs read from GICR_TYPER register
 * to core position.
 *
 * Calculating core position is dependent on MPIDR_EL1.MT bit. However, affinity
 * values read from GICR_TYPER don't have an MT field. To reuse the same
 * translation used for CPUs, we insert MT bit read from the PE's MPIDR into
 * that read from GICR_TYPER.
 *
 * Assumptions:
 *
 *   - All CPUs implemented in the system have MPIDR_EL1.MT bit set;
 *   - No CPUs implemented in the system use affinity level 3.
 */
static uint32_t versal_net_gicv3_mpidr_hash(u_register_t mpidr)
{
	mpidr |= (read_mpidr_el1() & MPIDR_MT_MASK);
	return plat_core_pos_by_mpidr(mpidr);
}

static const gicv3_driver_data_t versal_net_gic_data __unused = {
	.gicd_base = PLAT_VERSAL_NET_GICD_BASE,
	.gicr_base = 0U,
	.interrupt_props = versal_net_interrupt_props,
	.interrupt_props_num = ARRAY_SIZE(versal_net_interrupt_props),
	.rdistif_num = PLATFORM_CORE_COUNT,
	.rdistif_base_addrs = rdistif_base_addrs,
	.mpidr_to_core_pos = versal_net_gicv3_mpidr_hash
};

void __init plat_versal_net_gic_driver_init(void)
{
	/*
	 * The GICv3 driver is initialized in EL3 and does not need
	 * to be initialized again in SEL1. This is because the S-EL1
	 * can use GIC system registers to manage interrupts and does
	 * not need GIC interface base addresses to be configured.
	 */
#if IMAGE_BL31
	gicv3_driver_init(&versal_net_gic_data);
	gicr_frames = gicr_base_addrs;

	if (gicv3_rdistif_probe(gicr_frames[0]) == -1) {
		ERROR("No GICR base frame found for Primary CPU\n");
		panic();
	}
#endif
}

/******************************************************************************
 * Versal NET common helper to initialize the GIC. Only invoked by BL31
 *****************************************************************************/
void __init plat_versal_net_gic_init(void)
{
	gicv3_distif_init();
	gicv3_rdistif_init(plat_my_core_pos());
	gicv3_cpuif_enable(plat_my_core_pos());
}

/******************************************************************************
 * Versal NET common helper to enable the GIC CPU interface
 *****************************************************************************/
void plat_versal_net_gic_cpuif_enable(void)
{
	gicv3_cpuif_enable(plat_my_core_pos());
}

/******************************************************************************
 * Versal NET common helper to disable the GIC CPU interface
 *****************************************************************************/
void plat_versal_net_gic_cpuif_disable(void)
{
	gicv3_cpuif_disable(plat_my_core_pos());
}

/******************************************************************************
 * Versal NET common helper to initialize the per-cpu redistributor interface in
 * GICv3
 *****************************************************************************/
void plat_versal_net_gic_pcpu_init(void)
{
	int32_t result;
	const uintptr_t *plat_gicr_frames = gicr_frames;

	do {
		result = gicv3_rdistif_probe(*plat_gicr_frames);

		/* If the probe is successful, no need to proceed further */
		if (result == 0) {
			break;
		}

		plat_gicr_frames++;
	} while (*plat_gicr_frames != 0U);

	if (result == -1) {
		ERROR("No GICR base frame found for CPU 0x%lx\n", read_mpidr());
		panic();
	}

	gicv3_rdistif_init(plat_my_core_pos());
}

/******************************************************************************
 * Versal NET common helpers to power GIC redistributor interface
 *****************************************************************************/
void plat_versal_net_gic_redistif_on(void)
{
	gicv3_rdistif_on(plat_my_core_pos());
}

void plat_versal_net_gic_redistif_off(void)
{
	gicv3_rdistif_off(plat_my_core_pos());
}

/******************************************************************************
 * Versal NET common helper to save & restore the GICv3 on resume from system
 * suspend
 *****************************************************************************/
void plat_versal_net_gic_save(void)
{
	/*
	 * If an ITS is available, save its context before
	 * the Redistributor using:
	 * gicv3_its_save_disable(gits_base, &its_ctx[i])
	 * Additionnaly, an implementation-defined sequence may
	 * be required to save the whole ITS state.
	 */

	/*
	 * Save the GIC Redistributors and ITS contexts before the
	 * Distributor context. As we only handle SYSTEM SUSPEND API,
	 * we only need to save the context of the CPU that is issuing
	 * the SYSTEM SUSPEND call, i.e. the current CPU.
	 */
	gicv3_rdistif_save(plat_my_core_pos(), &rdist_ctx);

	/* Save the GIC Distributor context */
	gicv3_distif_save(&dist_ctx);

	/*
	 * From here, all the components of the GIC can be safely powered down
	 * as long as there is an alternate way to handle wakeup interrupt
	 * sources.
	 */
}

void plat_versal_net_gic_resume(void)
{
	/* Restore the GIC Distributor context */
	gicv3_distif_init_restore(&dist_ctx);

	/*
	 * Restore the GIC Redistributor and ITS contexts after the
	 * Distributor context. As we only handle SYSTEM SUSPEND API,
	 * we only need to restore the context of the CPU that issued
	 * the SYSTEM SUSPEND call.
	 */
	gicv3_rdistif_init_restore(plat_my_core_pos(), &rdist_ctx);

	/*
	 * If an ITS is available, restore its context after
	 * the Redistributor using:
	 * gicv3_its_restore(gits_base, &its_ctx[i])
	 * An implementation-defined sequence may be required to
	 * restore the whole ITS state. The ITS must also be
	 * re-enabled after this sequence has been executed.
	 */
}