/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2007 Catalin Patulea <cat@vv.carleton.ca>
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#include "config.h"
#include "cpu.h"
#include "system.h"
#include "debug.h"
#include "string.h"
#include "dsp-target.h"

/* A "DSP image" is an array of these, terminated by raw_data_size_half = 0. */
struct dsp_section {
	const unsigned short *raw_data;
	unsigned short physical_addr;
	unsigned short raw_data_size_half;
};

/* Must define struct dsp_section before including the image. */
#include "dsp_image_helloworld.h"

#ifdef DEBUG
static void dsp_status(void) {
	unsigned short hpib_ctl = IO_DSPC_HPIB_CONTROL;
	unsigned short hpib_stat = IO_DSPC_HPIB_STATUS;
	char buffer1[80], buffer2[80];
	
	DEBUGF("dsp_status(): clkc_hpib=%u clkc_dsp=%u",
		!!(IO_CLK_MOD0 & (1 << 11)), !!(IO_CLK_MOD0 & (1 << 10)));
	
	DEBUGF("dsp_status(): irq_dsphint=%u 7fff=%04x scratch_status=%04x"
		" acked=%04x",
		(IO_INTC_IRQ0 >> IRQ_DSPHINT) & 1, DSP_(0x7fff), DSP_(_status),
		DSP_(_acked));
#define B(f,w,b,m) if ((w & (1 << b)) == 0) \
					 strcat(f, "!"); \
				 strcat(f, #m "|");
	strcpy(buffer1, "");
	B(buffer1, hpib_ctl, 0, EN);
	B(buffer1, hpib_ctl, 3, NMI);
	B(buffer1, hpib_ctl, 5, EXCHG);
	B(buffer1, hpib_ctl, 7, DINT0);
	B(buffer1, hpib_ctl, 8, DRST);
	B(buffer1, hpib_ctl, 9, DHOLD);
	B(buffer1, hpib_ctl, 10, BIO);
	
	strcpy(buffer2, "");
	B(buffer2, hpib_stat, 8, HOLDA);
	B(buffer2, hpib_stat, 12, DXF);

	DEBUGF("dsp_status(): hpib: ctl=%s stat=%s", buffer1, buffer2);
#undef B
}
#endif

static void dsp_reset(void) {
	DSP_(0x7fff) = 0xdead;
	
	IO_DSPC_HPIB_CONTROL &= ~(1 << 8);
	/* HPIB bus cycles will lock up the ARM in here. Don't touch DSP RAM. */
	nop; nop;
	IO_DSPC_HPIB_CONTROL |= 1 << 8;
	
	/* TODO: Timeout. */
	while (DSP_(0x7fff) != 0);
}

void dsp_wake(void) {
	/* If this is called concurrently, we may overlap setting and resetting the
	   bit, which causes lost interrupts to the DSP. */
	int old_level = set_irq_level(IRQ_DISABLED);
	
	/* The first time you INT0 the DSP, the ROM loader will branch to your RST
	   handler. Subsequent times, your INT0 handler will get executed. */
	IO_DSPC_HPIB_CONTROL &= ~(1 << 7);
	nop; nop;
	IO_DSPC_HPIB_CONTROL |= 1 << 7;
	
	set_irq_level(old_level);
}

static void dsp_load(const struct dsp_section *im) {
	while (im->raw_data_size_half) {
		volatile unsigned short *data_ptr = &DSP_(im->physical_addr);
		unsigned int i;
		
		/* Use 16-bit writes. */
		if (im->raw_data) {
			DEBUGF("dsp_load(): loading %u words at 0x%04x (0x%08lx)",
				im->raw_data_size_half, im->physical_addr,
				(unsigned long)data_ptr);
			
			for (i = 0; i < im->raw_data_size_half; i++) {
				data_ptr[i] = im->raw_data[i];
			}
		} else {
			DEBUGF("dsp_load(): clearing %u words at 0x%04x (0x%08lx)",
				im->raw_data_size_half, im->physical_addr,
				(unsigned long)data_ptr);

			for (i = 0; i < im->raw_data_size_half; i++) {
				data_ptr[i] = 0;
			}
		}
		
		im++;
	}
}

void dsp_init(void) {
	IO_INTC_IRQ0 = 1 << 11;
	IO_INTC_EINT0 |= 1 << 11;

	dsp_reset();
	dsp_load(dsp_image_helloworld);
}

void DSPHINT(void) {
	unsigned int i;
	char buffer[80];
	
	IO_INTC_IRQ0 = 1 << 11;

	/* DSP stores one character per word. */
	for (i = 0; i < sizeof(buffer); i++) {
		buffer[i] = (&DSP_(_status))[i];
	}

	/* Release shared area to DSP. */
	dsp_wake();

	DEBUGF("DSP: %s", buffer);
}