#pragma once

/*
 *   This file is part of open_agb_firm
 *   Copyright (C) 2021 derrek, profi200
 *
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <assert.h>
#include "types.h"
#include "mem_map.h"
#include "util.h"


#define NDMA_REGS_BASE  (IO_MEM_ARM9_ONLY + 0x2000)
#define REG_NDMA_GCNT   *((vu32*)NDMA_REGS_BASE) // Global control.

// Note: The channel regs are offset by 4 (REG_NDMA_GLOBAL_CNT).
typedef struct
{
	vu32 sad;   // 0x00 Source address.
	vu32 dad;   // 0x04 Destination address.
	vu32 tcnt;  // 0x08 Total repeat length in words.
	vu32 wcnt;  // 0x0C Logical block size in words.
	vu32 bcnt;  // 0x10 Block transfer timing/interval.
	vu32 fdata; // 0x14 Fill data.
	vu32 cnt;   // 0x18 Control.
} NdmaCh;
static_assert(offsetof(NdmaCh, cnt) == 0x18, "Error: Member cnt of NdmaCh is not at offset 0x18!");

ALWAYS_INLINE NdmaCh* getNdmaChRegs(u8 c)
{
	return &((NdmaCh*)(NDMA_REGS_BASE + 4))[c];
}


// REG_NDMA_GCNT
#define NDMA_REG_READBACK    (1u) // Show internal state on REG_NDMAx_SAD/DAD/TCNT/WCNT. 3DS mode only.
#define NDMA_ROUND_ROBIN(n)  (1u<<31 | (intLog2(n) + 1)<<16) // DSP DMA/CPU cycles (power of 2). Maximum 16384.
#define NDMA_HIGHEST_PRIO    (0u)

// REG_NDMA_BCNT
// TODO: When is the delay happening during transfers?
// TODO: Does NDMA run at 67 MHz in 3DS mode? We will assume so for now.
#define NDMA_CYCLES(n)       (n)      // Maximum 65535. 0 means no delay/interval.
#define NDMA_PRESCALER_1     (0u)     // 67027964 Hz.
#define NDMA_PRESCALER_4     (1u<<16) // 16756991 Hz.
#define NDMA_PRESCALER_16    (2u<<16) // 4189247.75 Hz.
#define NDMA_PRESCALER_64    (3u<<16) // 1047311.9375 Hz.
#define NDMA_FASTEST         (NDMA_PRESCALER_1 | NDMA_CYCLES(0)) // Convenience macro.

// REG_NDMA_CNT
#define NDMA_DAD_INC         (0u)     // Destination address increment.
#define NDMA_DAD_DEC         (1u<<10) // Destination address decrement.
#define NDMA_DAD_FIX         (2u<<10) // Destination address fixed.
#define NDMA_DAD_RELOAD      (1u<<12) // Reload destination address on logical block end (REG_NDMAx_WCNT).
#define NDMA_SAD_INC         (0u)     // Source address increment.
#define NDMA_SAD_DEC         (1u<<13) // Source address decrement.
#define NDMA_SAD_FIX         (2u<<13) // Source address fixed.
#define NDMA_SAD_FILL        (3u<<13) // Source is REG_NDMAx_FDATA.
#define NDMA_SAD_RELOAD      (1u<<15) // Reload source address on logical block end (REG_NDMAx_WCNT).
#define NDMA_BURST_SHIFT     (16u)
#define NDMA_BURST(n)        (intLog2(n)<<NDMA_BURST_SHIFT) // Burst length is 2ⁿ words. Maximum 32768. Must be power of 2.
#define NDMA_TCNT_MODE       (0u)     // REG_NDMAx_TCNT mode.
#define NDMA_REPEAT_MODE     (1u<<29) // Repeat transfer infinitely.
#define NDMA_IRQ_EN          (1u<<30) // IRQ enable.
#define NDMA_EN              (1u<<31) // Channel enable/active.


enum
{
	NDMA_START_TIMER0       =  0u<<24,
	NDMA_START_TIMER1       =  1u<<24,
	NDMA_START_TIMER2       =  2u<<24,
	NDMA_START_TIMER3       =  3u<<24,
	NDMA_START_CTRCARD1     =  4u<<24, // Fires with SPICARD aswell but seems to be broken.
	NDMA_START_CTRCARD2     =  5u<<24, // Fires with SPICARD aswell but seems to be broken.
	NDMA_START_TOSHSD1      =  6u<<24,
	NDMA_START_TOSHSD3      =  7u<<24,
	NDMA_START_AES_IN       =  8u<<24, // AES write fifo.
	NDMA_START_AES_OUT      =  9u<<24, // AES read fifo.
	NDMA_START_SHA_IN       = 10u<<24,
	NDMA_START_SHA_OUT      = 11u<<24, // For chaining.
	NDMA_START_NTRCARD      = 12u<<24,
	// 13 and 14 unused?
	NDMA_START_DEV2DEV      = 15u<<24, // Needed for below startup modes.

	// Direct device to device modes.
	NDMA_START_CTRCARD1_AES = NDMA_START_DEV2DEV |  0u, // CTRCARD1 to AES.
	NDMA_START_CTRCARD2_AES = NDMA_START_DEV2DEV |  1u, // CTRCARD2 to AES.
	NDMA_START_AES_CTRCARD1 = NDMA_START_DEV2DEV |  2u, // AES to CTRCARD1.
	NDMA_START_AES_CTRCARD2 = NDMA_START_DEV2DEV |  3u, // AES to CTRCARD2.
	NDMA_START_CTRCARD1_SHA = NDMA_START_DEV2DEV |  4u, // CTRCARD1 to SHA.
	NDMA_START_CTRCARD2_SHA = NDMA_START_DEV2DEV |  5u, // CTRCARD2 to SHA.
	NDMA_START_SHA_CTRCARD1 = NDMA_START_DEV2DEV |  6u, // SHA to CTRCARD1.
	NDMA_START_SHA_CTRCARD2 = NDMA_START_DEV2DEV |  7u, // SHA to CTRCARD2.
	NDMA_START_TOSHSD1_AES  = NDMA_START_DEV2DEV |  8u, // TOSHSD1 to AES.
	NDMA_START_TOSHSD3_AES  = NDMA_START_DEV2DEV |  9u, // TOSHSD3 to AES.
	NDMA_START_AES_TOSHSD1  = NDMA_START_DEV2DEV | 10u, // AES to TOSHSD1.
	NDMA_START_AES_TOSHSD3  = NDMA_START_DEV2DEV | 11u, // AES to TOSHSD3.
	NDMA_START_TOSHSD1_SHA  = NDMA_START_DEV2DEV | 12u, // TOSHSD1 to SHA.
	NDMA_START_TOSHSD3_SHA  = NDMA_START_DEV2DEV | 13u, // TOSHSD3 to SHA.
	NDMA_START_SHA_TOSHSD1  = NDMA_START_DEV2DEV | 14u, // SHA to TOSHSD1.
	NDMA_START_SHA_TOSHSD3  = NDMA_START_DEV2DEV | 15u, // SHA to TOSHSD3.
	NDMA_START_AES_SHA      = NDMA_START_DEV2DEV | 16u, // AES to SHA.
	NDMA_START_SHA_AES      = NDMA_START_DEV2DEV | 17u, // SHA to AES.
	// 18-31 unused?

	// This bit is technically not part of the startup modes.
	NDMA_START_IMMEDIATE    = 16u<<24
};



/**
 * @brief      Initializes all NDMA channels.
 */
void NDMA_init(void);

/**
 * @brief      Copies data using the NDMA engine.
 *
 * @param      dest    Pointer to destination memory. Must be 4 bytes aligned.
 * @param      source  Pointer to source data. Must be 4 bytes aligned.
 * @param[in]  size    The size of the data. Must be multiple of 4.
 */
void NDMA_copy(u32 *dest, const u32 *source, u32 size);

/**
 * @brief      Fills memory with the given value using the NDMA engine.
 *
 * @param      dest   Pointer to destination memory. Must be 4 bytes aligned.
 * @param[in]  value  The value each 32-bit word will be set to.
 * @param[in]  size   The size of the memory to fill. Must be multiple of 4.
 */
void NDMA_fill(u32 *dest, u32 value, u32 size);