[picodrive.git] / cpu / sh2 / sh2.c

/*
 * PicoDrive
 * (C) notaz, 2009,2010
 *
 * This work is licensed under the terms of MAME license.
 * See COPYING file in the top-level directory.
 */
#include <string.h>
#include <stddef.h>

#include "sh2.h"
#include "../debug.h"
#include "compiler.h"

#define I 0xf0

int sh2_init(SH2 *sh2, int is_slave)
{
	int ret = 0;

	memset(sh2, 0, offsetof(SH2, mult_m68k_to_sh2));
	sh2->is_slave = is_slave;
	pdb_register_cpu(sh2, PDBCT_SH2, is_slave ? "ssh2" : "msh2");
#ifdef DRC_SH2
	ret = sh2_drc_init(sh2);
#endif
	return ret;
}

void sh2_finish(SH2 *sh2)
{
#ifdef DRC_SH2
	sh2_drc_finish(sh2);
#endif
}

void sh2_reset(SH2 *sh2)
{
	sh2->pc = p32x_sh2_read32(0, sh2);
	sh2->r[15] = p32x_sh2_read32(4, sh2);
	sh2->sr = I;
	sh2->vbr = 0;
	sh2->pending_int_irq = 0;
}

void sh2_do_irq(SH2 *sh2, int level, int vector)
{
	sh2->r[15] -= 4;
	p32x_sh2_write32(sh2->r[15], sh2->sr, sh2);	/* push SR onto stack */
	sh2->r[15] -= 4;
	p32x_sh2_write32(sh2->r[15], sh2->pc, sh2);	/* push PC onto stack */

	/* set I flags in SR */
	sh2->sr = (sh2->sr & ~I) | (level << 4);

	/* fetch PC */
	sh2->pc = p32x_sh2_read32(sh2->vbr + vector * 4, sh2);

	/* 13 cycles at best */
	sh2->m68krcycles_done += C_SH2_TO_M68K(*sh2, 13);
//	sh2->icount -= 13;
}

int sh2_irl_irq(SH2 *sh2, int level, int nested_call)
{
	int taken;

	sh2->pending_irl = level;
	if (level < sh2->pending_int_irq)
		level = sh2->pending_int_irq;
	sh2->pending_level = level;

	taken = (level > ((sh2->sr >> 4) & 0x0f));
	if (taken) {
		if (!nested_call) {
			// not in memhandler, so handle this now (recompiler friendly)
			// do this to avoid missing irqs that other SH2 might clear
			int vector = sh2->irq_callback(sh2, level);
			sh2_do_irq(sh2, level, vector);
		}
		else
			sh2->test_irq = 1;
	}
	return taken;
}

void sh2_internal_irq(SH2 *sh2, int level, int vector)
{
	// FIXME: multiple internal irqs not handled..
	// assuming internal irqs never clear until accepted
	sh2->pending_int_irq = level;
	sh2->pending_int_vector = vector;
	if (level > sh2->pending_level)
		sh2->pending_level = level;

	sh2->test_irq = 1;
}

#define SH2_REG_SIZE (offsetof(SH2, macl) + sizeof(sh2->macl))

void sh2_pack(const SH2 *sh2, unsigned char *buff)
{
	unsigned int *p;

	memcpy(buff, sh2, SH2_REG_SIZE);
	p = (void *)(buff + SH2_REG_SIZE);

	p[0] = sh2->pending_int_irq;
	p[1] = sh2->pending_int_vector;
}

void sh2_unpack(SH2 *sh2, const unsigned char *buff)
{
	unsigned int *p;

	memcpy(sh2, buff, SH2_REG_SIZE);
	p = (void *)(buff + SH2_REG_SIZE);

	sh2->pending_int_irq = p[0];
	sh2->pending_int_vector = p[1];
}
Commit	Line	Data
	1	/*
	2	* PicoDrive
	3	* (C) notaz, 2009,2010
	4	*
	5	* This work is licensed under the terms of MAME license.
	6	* See COPYING file in the top-level directory.
	7	*/
	8	#include <string.h>
	9	#include <stddef.h>
	10
	11	#include "sh2.h"
	12	#include "../debug.h"
	13	#include "compiler.h"
	14
	15	#define I 0xf0
	16
	17	int sh2_init(SH2 *sh2, int is_slave)
	18	{
	19	int ret = 0;
	20
	21	memset(sh2, 0, offsetof(SH2, mult_m68k_to_sh2));
	22	sh2->is_slave = is_slave;
	23	pdb_register_cpu(sh2, PDBCT_SH2, is_slave ? "ssh2" : "msh2");
	24	#ifdef DRC_SH2
	25	ret = sh2_drc_init(sh2);
	26	#endif
	27	return ret;
	28	}
	29
	30	void sh2_finish(SH2 *sh2)
	31	{
	32	#ifdef DRC_SH2
	33	sh2_drc_finish(sh2);
	34	#endif
	35	}
	36
	37	void sh2_reset(SH2 *sh2)
	38	{
	39	sh2->pc = p32x_sh2_read32(0, sh2);
	40	sh2->r[15] = p32x_sh2_read32(4, sh2);
	41	sh2->sr = I;
	42	sh2->vbr = 0;
	43	sh2->pending_int_irq = 0;
	44	}
	45
	46	void sh2_do_irq(SH2 *sh2, int level, int vector)
	47	{
	48	sh2->r[15] -= 4;
	49	p32x_sh2_write32(sh2->r[15], sh2->sr, sh2); /* push SR onto stack */
	50	sh2->r[15] -= 4;
	51	p32x_sh2_write32(sh2->r[15], sh2->pc, sh2); /* push PC onto stack */
	52
	53	/* set I flags in SR */
	54	sh2->sr = (sh2->sr & ~I) \| (level << 4);
	55
	56	/* fetch PC */
	57	sh2->pc = p32x_sh2_read32(sh2->vbr + vector * 4, sh2);
	58
	59	/* 13 cycles at best */
	60	sh2->m68krcycles_done += C_SH2_TO_M68K(*sh2, 13);
	61	// sh2->icount -= 13;
	62	}
	63
	64	int sh2_irl_irq(SH2 *sh2, int level, int nested_call)
	65	{
	66	int taken;
	67
	68	sh2->pending_irl = level;
	69	if (level < sh2->pending_int_irq)
	70	level = sh2->pending_int_irq;
	71	sh2->pending_level = level;
	72
	73	taken = (level > ((sh2->sr >> 4) & 0x0f));
	74	if (taken) {
	75	if (!nested_call) {
	76	// not in memhandler, so handle this now (recompiler friendly)
	77	// do this to avoid missing irqs that other SH2 might clear
	78	int vector = sh2->irq_callback(sh2, level);
	79	sh2_do_irq(sh2, level, vector);
	80	}
	81	else
	82	sh2->test_irq = 1;
	83	}
	84	return taken;
	85	}
	86
	87	void sh2_internal_irq(SH2 *sh2, int level, int vector)
	88	{
	89	// FIXME: multiple internal irqs not handled..
	90	// assuming internal irqs never clear until accepted
	91	sh2->pending_int_irq = level;
	92	sh2->pending_int_vector = vector;
	93	if (level > sh2->pending_level)
	94	sh2->pending_level = level;
	95
	96	sh2->test_irq = 1;
	97	}
	98
	99	#define SH2_REG_SIZE (offsetof(SH2, macl) + sizeof(sh2->macl))
	100
	101	void sh2_pack(const SH2 sh2, unsigned char buff)
	102	{
	103	unsigned int *p;
	104
	105	memcpy(buff, sh2, SH2_REG_SIZE);
	106	p = (void *)(buff + SH2_REG_SIZE);
	107
	108	p[0] = sh2->pending_int_irq;
	109	p[1] = sh2->pending_int_vector;
	110	}
	111
	112	void sh2_unpack(SH2 sh2, const unsigned char buff)
	113	{
	114	unsigned int *p;
	115
	116	memcpy(sh2, buff, SH2_REG_SIZE);
	117	p = (void *)(buff + SH2_REG_SIZE);
	118
	119	sh2->pending_int_irq = p[0];
	120	sh2->pending_int_vector = p[1];
	121	}
	122