SHIX board emulation (Samuel Tardieu)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1862 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 836 insertions, 0 deletions

diff --git a/hw/sh7750.c b/hw/sh7750.c
new file mode 100644
index 0000000000..041e3eed1b
--- /dev/null
+++ b/hw/sh7750.c
@@ -0,0 +1,836 @@
+/*
+ * SH7750 device
+ * 
+ * Copyright (c) 2005 Samuel Tardieu
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <stdio.h>
+#include <assert.h>
+#include "vl.h"
+#include "sh7750_regs.h"
+#include "sh7750_regnames.h"
+
+typedef struct {
+    uint8_t data[16];
+    uint8_t length;		/* Number of characters in the FIFO */
+    uint8_t write_idx;		/* Index of first character to write */
+    uint8_t read_idx;		/* Index of first character to read */
+} fifo;
+
+#define NB_DEVICES 4
+
+typedef struct SH7750State {
+    /* CPU */
+    CPUSH4State *cpu;
+    /* Peripheral frequency in Hz */
+    uint32_t periph_freq;
+    /* SDRAM controller */
+    uint16_t rfcr;
+    /* First serial port */
+    CharDriverState *serial1;
+    uint8_t scscr1;
+    uint8_t scsmr1;
+    uint8_t scbrr1;
+    uint8_t scssr1;
+    uint8_t scssr1_read;
+    uint8_t sctsr1;
+    uint8_t sctsr1_loaded;
+    uint8_t sctdr1;
+    uint8_t scrdr1;
+    /* Second serial port */
+    CharDriverState *serial2;
+    uint16_t sclsr2;
+    uint16_t scscr2;
+    uint16_t scfcr2;
+    uint16_t scfsr2;
+    uint16_t scsmr2;
+    uint8_t scbrr2;
+    fifo serial2_receive_fifo;
+    fifo serial2_transmit_fifo;
+    /* Timers */
+    uint8_t tstr;
+    /* Timer 0 */
+    QEMUTimer *timer0;
+    uint16_t tcr0;
+    uint32_t tcor0;
+    uint32_t tcnt0;
+    /* IO ports */
+    uint16_t gpioic;
+    uint32_t pctra;
+    uint32_t pctrb;
+    uint16_t portdira;		/* Cached */
+    uint16_t portpullupa;	/* Cached */
+    uint16_t portdirb;		/* Cached */
+    uint16_t portpullupb;	/* Cached */
+    uint16_t pdtra;
+    uint16_t pdtrb;
+    uint16_t periph_pdtra;	/* Imposed by the peripherals */
+    uint16_t periph_portdira;	/* Direction seen from the peripherals */
+    uint16_t periph_pdtrb;	/* Imposed by the peripherals */
+    uint16_t periph_portdirb;	/* Direction seen from the peripherals */
+    sh7750_io_device *devices[NB_DEVICES];	/* External peripherals */
+    /* Cache */
+    uint32_t ccr;
+} SH7750State;
+
+/**********************************************************************
+ Timers
+**********************************************************************/
+
+/* XXXXX At this time, timer0 works in underflow only mode, that is
+   the value of tcnt0 is read at alarm computation time and cannot
+   be read back by the guest OS */
+
+static void start_timer0(SH7750State * s)
+{
+    uint64_t now, next, prescaler;
+
+    if ((s->tcr0 & 6) == 6) {
+	fprintf(stderr, "rtc clock for timer 0 not supported\n");
+	assert(0);
+    }
+
+    if ((s->tcr0 & 7) == 5) {
+	fprintf(stderr, "timer 0 configuration not supported\n");
+	assert(0);
+    }
+
+    if ((s->tcr0 & 4) == 4)
+	prescaler = 1024;
+    else
+	prescaler = 4 << (s->tcr0 & 3);
+
+    now = qemu_get_clock(vm_clock);
+    /* XXXXX */
+    next =
+	now + muldiv64(prescaler * s->tcnt0, ticks_per_sec,
+		       s->periph_freq);
+    if (next == now)
+	next = now + 1;
+    fprintf(stderr, "now=%016llx, next=%016llx\n", now, next);
+    fprintf(stderr, "timer will underflow in %f seconds\n",
+	    (float) (next - now) / (float) ticks_per_sec);
+
+    qemu_mod_timer(s->timer0, next);
+}
+
+static void timer_start_changed(SH7750State * s)
+{
+    if (s->tstr & SH7750_TSTR_STR0) {
+	start_timer0(s);
+    } else {
+	fprintf(stderr, "timer 0 is stopped\n");
+	qemu_del_timer(s->timer0);
+    }
+}
+
+static void timer0_cb(void *opaque)
+{
+    SH7750State *s = opaque;
+
+    s->tcnt0 = (uint32_t) 0;	/* XXXXX */
+    if (--s->tcnt0 == (uint32_t) - 1) {
+	fprintf(stderr, "timer 0 underflow\n");
+	s->tcnt0 = s->tcor0;
+	s->tcr0 |= SH7750_TCR_UNF;
+	if (s->tcr0 & SH7750_TCR_UNIE) {
+	    fprintf(stderr,
+		    "interrupt generation for timer 0 not supported\n");
+	    assert(0);
+	}
+    }
+    start_timer0(s);
+}
+
+static void init_timers(SH7750State * s)
+{
+    s->tcor0 = 0xffffffff;
+    s->tcnt0 = 0xffffffff;
+    s->timer0 = qemu_new_timer(vm_clock, &timer0_cb, s);
+}
+
+/**********************************************************************
+ First serial port
+**********************************************************************/
+
+static int serial1_can_receive(void *opaque)
+{
+    SH7750State *s = opaque;
+
+    return s->scscr1 & SH7750_SCSCR_RE;
+}
+
+static void serial1_receive_char(SH7750State * s, uint8_t c)
+{
+    if (s->scssr1 & SH7750_SCSSR1_RDRF) {
+	s->scssr1 |= SH7750_SCSSR1_ORER;
+	return;
+    }
+
+    s->scrdr1 = c;
+    s->scssr1 |= SH7750_SCSSR1_RDRF;
+}
+
+static void serial1_receive(void *opaque, const uint8_t * buf, int size)
+{
+    SH7750State *s = opaque;
+    int i;
+
+    for (i = 0; i < size; i++) {
+	serial1_receive_char(s, buf[i]);
+    }
+}
+
+static void serial1_event(void *opaque, int event)
+{
+    assert(0);
+}
+
+static void serial1_maybe_send(SH7750State * s)
+{
+    uint8_t c;
+
+    if (s->scssr1 & SH7750_SCSSR1_TDRE)
+	return;
+    c = s->sctdr1;
+    s->scssr1 |= SH7750_SCSSR1_TDRE | SH7750_SCSSR1_TEND;
+    if (s->scscr1 & SH7750_SCSCR_TIE) {
+	fprintf(stderr, "interrupts for serial port 1 not implemented\n");
+	assert(0);
+    }
+    /* XXXXX Check for errors in write */
+    qemu_chr_write(s->serial1, &c, 1);
+}
+
+static void serial1_change_scssr1(SH7750State * s, uint8_t mem_value)
+{
+    uint8_t new_flags;
+
+    /* If transmit disable, TDRE and TEND stays up */
+    if ((s->scscr1 & SH7750_SCSCR_TE) == 0) {
+	mem_value |= SH7750_SCSSR1_TDRE | SH7750_SCSSR1_TEND;
+    }
+
+    /* Only clear bits which have been read before and do not set any bit
+       in the flags */
+    new_flags = s->scssr1 & ~s->scssr1_read;	/* Preserve unread flags */
+    new_flags &= mem_value | ~s->scssr1_read;	/* Clear read flags */
+
+    s->scssr1 = (new_flags & 0xf8) | (mem_value & 1);
+    s->scssr1_read &= mem_value;
+
+    /* If TDRE has been cleared, TEND will also be cleared */
+    if ((s->scssr1 & SH7750_SCSSR1_TDRE) == 0) {
+	s->scssr1 &= ~SH7750_SCSSR1_TEND;
+    }
+
+    /* Check for transmission to start */
+    serial1_maybe_send(s);
+}
+
+static void serial1_update_parameters(SH7750State * s)
+{
+    QEMUSerialSetParams ssp;
+
+    if (s->scsmr1 & SH7750_SCSMR_CHR_7)
+	ssp.data_bits = 7;
+    else
+	ssp.data_bits = 8;
+    if (s->scsmr1 & SH7750_SCSMR_PE) {
+	if (s->scsmr1 & SH7750_SCSMR_PM_ODD)
+	    ssp.parity = 'O';
+	else
+	    ssp.parity = 'E';
+    } else
+	ssp.parity = 'N';
+    if (s->scsmr1 & SH7750_SCSMR_STOP_2)
+	ssp.stop_bits = 2;
+    else
+	ssp.stop_bits = 1;
+    fprintf(stderr, "SCSMR1=%04x SCBRR1=%02x\n", s->scsmr1, s->scbrr1);
+    ssp.speed = s->periph_freq /
+	(32 * s->scbrr1 * (1 << (2 * (s->scsmr1 & 3)))) - 1;
+    fprintf(stderr, "data bits=%d, stop bits=%d, parity=%c, speed=%d\n",
+	    ssp.data_bits, ssp.stop_bits, ssp.parity, ssp.speed);
+    qemu_chr_ioctl(s->serial1, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
+}
+
+static void scscr1_changed(SH7750State * s)
+{
+    if (s->scscr1 & (SH7750_SCSCR_TE | SH7750_SCSCR_RE)) {
+	if (!s->serial1) {
+	    fprintf(stderr, "serial port 1 not bound to anything\n");
+	    assert(0);
+	}
+	serial1_update_parameters(s);
+    }
+    if ((s->scscr1 & SH7750_SCSCR_RE) == 0) {
+	s->scssr1 |= SH7750_SCSSR1_TDRE;
+    }
+}
+
+static void init_serial1(SH7750State * s, int serial_nb)
+{
+    CharDriverState *chr;
+
+    s->scssr1 = 0x84;
+    chr = serial_hds[serial_nb];
+    if (!chr) {
+	fprintf(stderr,
+		"no serial port associated to SH7750 first serial port\n");
+	return;
+    }
+
+    s->serial1 = chr;
+    qemu_chr_add_read_handler(chr, serial1_can_receive,
+			      serial1_receive, s);
+    qemu_chr_add_event_handler(chr, serial1_event);
+}
+
+/**********************************************************************
+ Second serial port
+**********************************************************************/
+
+static int serial2_can_receive(void *opaque)
+{
+    SH7750State *s = opaque;
+    static uint8_t max_fifo_size[] = { 15, 1, 4, 6, 8, 10, 12, 14 };
+
+    return s->serial2_receive_fifo.length <
+	max_fifo_size[(s->scfcr2 >> 9) & 7];
+}
+
+static void serial2_adjust_receive_flags(SH7750State * s)
+{
+    static uint8_t max_fifo_size[] = { 1, 4, 8, 14 };
+
+    /* XXXXX Add interrupt generation */
+    if (s->serial2_receive_fifo.length >=
+	max_fifo_size[(s->scfcr2 >> 7) & 3]) {
+	s->scfsr2 |= SH7750_SCFSR2_RDF;
+	s->scfsr2 &= ~SH7750_SCFSR2_DR;
+    } else {
+	s->scfsr2 &= ~SH7750_SCFSR2_RDF;
+	if (s->serial2_receive_fifo.length > 0)
+	    s->scfsr2 |= SH7750_SCFSR2_DR;
+	else
+	    s->scfsr2 &= ~SH7750_SCFSR2_DR;
+    }
+}
+
+static void serial2_append_char(SH7750State * s, uint8_t c)
+{
+    if (s->serial2_receive_fifo.length == 16) {
+	/* Overflow */
+	s->sclsr2 |= SH7750_SCLSR2_ORER;
+	return;
+    }
+
+    s->serial2_receive_fifo.data[s->serial2_receive_fifo.write_idx++] = c;
+    s->serial2_receive_fifo.length++;
+    serial2_adjust_receive_flags(s);
+}
+
+static void serial2_receive(void *opaque, const uint8_t * buf, int size)
+{
+    SH7750State *s = opaque;
+    int i;
+
+    for (i = 0; i < size; i++)
+	serial2_append_char(s, buf[i]);
+}
+
+static void serial2_event(void *opaque, int event)
+{
+    /* XXXXX */
+    assert(0);
+}
+
+static void serial2_update_parameters(SH7750State * s)
+{
+    QEMUSerialSetParams ssp;
+
+    if (s->scsmr2 & SH7750_SCSMR_CHR_7)
+	ssp.data_bits = 7;
+    else
+	ssp.data_bits = 8;
+    if (s->scsmr2 & SH7750_SCSMR_PE) {
+	if (s->scsmr2 & SH7750_SCSMR_PM_ODD)
+	    ssp.parity = 'O';
+	else
+	    ssp.parity = 'E';
+    } else
+	ssp.parity = 'N';
+    if (s->scsmr2 & SH7750_SCSMR_STOP_2)
+	ssp.stop_bits = 2;
+    else
+	ssp.stop_bits = 1;
+    fprintf(stderr, "SCSMR2=%04x SCBRR2=%02x\n", s->scsmr2, s->scbrr2);
+    ssp.speed = s->periph_freq /
+	(32 * s->scbrr2 * (1 << (2 * (s->scsmr2 & 3)))) - 1;
+    fprintf(stderr, "data bits=%d, stop bits=%d, parity=%c, speed=%d\n",
+	    ssp.data_bits, ssp.stop_bits, ssp.parity, ssp.speed);
+    qemu_chr_ioctl(s->serial2, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
+}
+
+static void scscr2_changed(SH7750State * s)
+{
+    if (s->scscr2 & (SH7750_SCSCR_TE | SH7750_SCSCR_RE)) {
+	if (!s->serial2) {
+	    fprintf(stderr, "serial port 2 not bound to anything\n");
+	    assert(0);
+	}
+	serial2_update_parameters(s);
+    }
+}
+
+static void init_serial2(SH7750State * s, int serial_nb)
+{
+    CharDriverState *chr;
+
+    s->scfsr2 = 0x0060;
+
+    chr = serial_hds[serial_nb];
+    if (!chr) {
+	fprintf(stderr,
+		"no serial port associated to SH7750 second serial port\n");
+	return;
+    }
+
+    s->serial2 = chr;
+    qemu_chr_add_read_handler(chr, serial2_can_receive,
+			      serial2_receive, s);
+    qemu_chr_add_event_handler(chr, serial2_event);
+}
+
+static void init_serial_ports(SH7750State * s)
+{
+    init_serial1(s, 0);
+    init_serial2(s, 1);
+}
+
+/**********************************************************************
+ I/O ports
+**********************************************************************/
+
+int sh7750_register_io_device(SH7750State * s, sh7750_io_device * device)
+{
+    int i;
+
+    for (i = 0; i < NB_DEVICES; i++) {
+	if (s->devices[i] == NULL) {
+	    s->devices[i] = device;
+	    return 0;
+	}
+    }
+    return -1;
+}
+
+static uint16_t portdir(uint32_t v)
+{
+#define EVENPORTMASK(n) ((v & (1<<((n)<<1))) >> (n))
+    return
+	EVENPORTMASK(15) | EVENPORTMASK(14) | EVENPORTMASK(13) |
+	EVENPORTMASK(12) | EVENPORTMASK(11) | EVENPORTMASK(10) |
+	EVENPORTMASK(9) | EVENPORTMASK(8) | EVENPORTMASK(7) |
+	EVENPORTMASK(6) | EVENPORTMASK(5) | EVENPORTMASK(4) |
+	EVENPORTMASK(3) | EVENPORTMASK(2) | EVENPORTMASK(1) |
+	EVENPORTMASK(0);
+}
+
+static uint16_t portpullup(uint32_t v)
+{
+#define ODDPORTMASK(n) ((v & (1<<(((n)<<1)+1))) >> (n))
+    return
+	ODDPORTMASK(15) | ODDPORTMASK(14) | ODDPORTMASK(13) |
+	ODDPORTMASK(12) | ODDPORTMASK(11) | ODDPORTMASK(10) |
+	ODDPORTMASK(9) | ODDPORTMASK(8) | ODDPORTMASK(7) | ODDPORTMASK(6) |
+	ODDPORTMASK(5) | ODDPORTMASK(4) | ODDPORTMASK(3) | ODDPORTMASK(2) |
+	ODDPORTMASK(1) | ODDPORTMASK(0);
+}
+
+static uint16_t porta_lines(SH7750State * s)
+{
+    return (s->portdira & s->pdtra) |	/* CPU */
+	(s->periph_portdira & s->periph_pdtra) |	/* Peripherals */
+	(~(s->portdira | s->periph_portdira) & s->portpullupa);	/* Pullups */
+}
+
+static uint16_t portb_lines(SH7750State * s)
+{
+    return (s->portdirb & s->pdtrb) |	/* CPU */
+	(s->periph_portdirb & s->periph_pdtrb) |	/* Peripherals */
+	(~(s->portdirb | s->periph_portdirb) & s->portpullupb);	/* Pullups */
+}
+
+static void gen_port_interrupts(SH7750State * s)
+{
+    /* XXXXX interrupts not generated */
+}
+
+static void porta_changed(SH7750State * s, uint16_t prev)
+{
+    uint16_t currenta, changes;
+    int i, r = 0;
+
+#if 0
+    fprintf(stderr, "porta changed from 0x%04x to 0x%04x\n",
+	    prev, porta_lines(s));
+    fprintf(stderr, "pdtra=0x%04x, pctra=0x%08x\n", s->pdtra, s->pctra);
+#endif
+    currenta = porta_lines(s);
+    if (currenta == prev)
+	return;
+    changes = currenta ^ prev;
+
+    for (i = 0; i < NB_DEVICES; i++) {
+	if (s->devices[i] && (s->devices[i]->portamask_trigger & changes)) {
+	    r |= s->devices[i]->port_change_cb(currenta, portb_lines(s),
+					       &s->periph_pdtra,
+					       &s->periph_portdira,
+					       &s->periph_pdtrb,
+					       &s->periph_portdirb);
+	}
+    }
+
+    if (r)
+	gen_port_interrupts(s);
+}
+
+static void portb_changed(SH7750State * s, uint16_t prev)
+{
+    uint16_t currentb, changes;
+    int i, r = 0;
+
+    currentb = portb_lines(s);
+    if (currentb == prev)
+	return;
+    changes = currentb ^ prev;
+
+    for (i = 0; i < NB_DEVICES; i++) {
+	if (s->devices[i] && (s->devices[i]->portbmask_trigger & changes)) {
+	    r |= s->devices[i]->port_change_cb(portb_lines(s), currentb,
+					       &s->periph_pdtra,
+					       &s->periph_portdira,
+					       &s->periph_pdtrb,
+					       &s->periph_portdirb);
+	}
+    }
+
+    if (r)
+	gen_port_interrupts(s);
+}
+
+/**********************************************************************
+ Memory
+**********************************************************************/
+
+static void error_access(const char *kind, target_phys_addr_t addr)
+{
+    fprintf(stderr, "%s to %s (0x%08x) not supported\n",
+	    kind, regname(addr), addr);
+}
+
+static void ignore_access(const char *kind, target_phys_addr_t addr)
+{
+    fprintf(stderr, "%s to %s (0x%08x) ignored\n",
+	    kind, regname(addr), addr);
+}
+
+static uint32_t sh7750_mem_readb(void *opaque, target_phys_addr_t addr)
+{
+    SH7750State *s = opaque;
+    uint8_t r;
+
+    switch (addr) {
+    case SH7750_SCSSR1_A7:
+	r = s->scssr1;
+	s->scssr1_read |= r;
+	return s->scssr1;
+    case SH7750_SCRDR1_A7:
+	s->scssr1 &= ~SH7750_SCSSR1_RDRF;
+	return s->scrdr1;
+    default:
+	error_access("byte read", addr);
+	assert(0);
+    }
+}
+
+static uint32_t sh7750_mem_readw(void *opaque, target_phys_addr_t addr)
+{
+    SH7750State *s = opaque;
+    uint16_t r;
+
+    switch (addr) {
+    case SH7750_RFCR_A7:
+	fprintf(stderr,
+		"Read access to refresh count register, incrementing\n");
+	return s->rfcr++;
+    case SH7750_TCR0_A7:
+	return s->tcr0;
+    case SH7750_SCLSR2_A7:
+	/* Read and clear overflow bit */
+	r = s->sclsr2;
+	s->sclsr2 = 0;
+	return r;
+    case SH7750_SCSFR2_A7:
+	return s->scfsr2;
+    case SH7750_PDTRA_A7:
+	return porta_lines(s);
+    case SH7750_PDTRB_A7:
+	return portb_lines(s);
+    default:
+	error_access("word read", addr);
+	assert(0);
+    }
+}
+
+static uint32_t sh7750_mem_readl(void *opaque, target_phys_addr_t addr)
+{
+    SH7750State *s = opaque;
+
+    switch (addr) {
+    case SH7750_MMUCR_A7:
+	return s->cpu->mmucr;
+    case SH7750_PTEH_A7:
+	return s->cpu->pteh;
+    case SH7750_PTEL_A7:
+	return s->cpu->ptel;
+    case SH7750_TTB_A7:
+	return s->cpu->ttb;
+    case SH7750_TEA_A7:
+	return s->cpu->tea;
+    case SH7750_TRA_A7:
+	return s->cpu->tra;
+    case SH7750_EXPEVT_A7:
+	return s->cpu->expevt;
+    case SH7750_INTEVT_A7:
+	return s->cpu->intevt;
+    case SH7750_CCR_A7:
+	return s->ccr;
+    case 0x1f000030:		/* Processor version PVR */
+	return 0x00050000;	/* SH7750R */
+    case 0x1f000040:		/* Processor version CVR */
+	return 0x00110000;	/* Minimum caches */
+    case 0x1f000044:		/* Processor version PRR */
+	return 0x00000100;	/* SH7750R */
+    default:
+	error_access("long read", addr);
+	assert(0);
+    }
+}
+
+static void sh7750_mem_writeb(void *opaque, target_phys_addr_t addr,
+			      uint32_t mem_value)
+{
+    SH7750State *s = opaque;
+
+    switch (addr) {
+	/* PRECHARGE ? XXXXX */
+    case SH7750_PRECHARGE0_A7:
+    case SH7750_PRECHARGE1_A7:
+	ignore_access("byte write", addr);
+	return;
+    case SH7750_SCBRR2_A7:
+	s->scbrr2 = mem_value;
+	return;
+    case SH7750_TSTR_A7:
+	s->tstr = mem_value;
+	timer_start_changed(s);
+	return;
+    case SH7750_SCSCR1_A7:
+	s->scscr1 = mem_value;
+	scscr1_changed(s);
+	return;
+    case SH7750_SCSMR1_A7:
+	s->scsmr1 = mem_value;
+	return;
+    case SH7750_SCBRR1_A7:
+	s->scbrr1 = mem_value;
+	return;
+    case SH7750_SCTDR1_A7:
+	s->scssr1 &= ~SH7750_SCSSR1_TEND;
+	s->sctdr1 = mem_value;
+	return;
+    case SH7750_SCSSR1_A7:
+	serial1_change_scssr1(s, mem_value);
+	return;
+    default:
+	error_access("byte write", addr);
+	assert(0);
+    }
+}
+
+static void sh7750_mem_writew(void *opaque, target_phys_addr_t addr,
+			      uint32_t mem_value)
+{
+    SH7750State *s = opaque;
+    uint16_t temp;
+
+    switch (addr) {
+	/* SDRAM controller */
+    case SH7750_SCBRR1_A7:
+    case SH7750_SCBRR2_A7:
+    case SH7750_BCR2_A7:
+    case SH7750_BCR3_A7:
+    case SH7750_RTCOR_A7:
+    case SH7750_RTCNT_A7:
+    case SH7750_RTCSR_A7:
+	ignore_access("word write", addr);
+	return;
+	/* IO ports */
+    case SH7750_PDTRA_A7:
+	temp = porta_lines(s);
+	s->pdtra = mem_value;
+	porta_changed(s, temp);
+	return;
+    case SH7750_PDTRB_A7:
+	temp = portb_lines(s);
+	s->pdtrb = mem_value;
+	portb_changed(s, temp);
+	return;
+    case SH7750_RFCR_A7:
+	fprintf(stderr, "Write access to refresh count register\n");
+	s->rfcr = mem_value;
+	return;
+    case SH7750_SCLSR2_A7:
+	s->sclsr2 = mem_value;
+	return;
+    case SH7750_SCSCR2_A7:
+	s->scscr2 = mem_value;
+	scscr2_changed(s);
+	return;
+    case SH7750_SCFCR2_A7:
+	s->scfcr2 = mem_value;
+	return;
+    case SH7750_SCSMR2_A7:
+	s->scsmr2 = mem_value;
+	return;
+    case SH7750_TCR0_A7:
+	s->tcr0 = mem_value;
+	return;
+    case SH7750_GPIOIC_A7:
+	s->gpioic = mem_value;
+	if (mem_value != 0) {
+	    fprintf(stderr, "I/O interrupts not implemented\n");
+	    assert(0);
+	}
+	return;
+    default:
+	error_access("word write", addr);
+	assert(0);
+    }
+}
+
+static void sh7750_mem_writel(void *opaque, target_phys_addr_t addr,
+			      uint32_t mem_value)
+{
+    SH7750State *s = opaque;
+    uint16_t temp;
+
+    switch (addr) {
+	/* SDRAM controller */
+    case SH7750_BCR1_A7:
+    case SH7750_BCR4_A7:
+    case SH7750_WCR1_A7:
+    case SH7750_WCR2_A7:
+    case SH7750_WCR3_A7:
+    case SH7750_MCR_A7:
+	ignore_access("long write", addr);
+	return;
+	/* IO ports */
+    case SH7750_PCTRA_A7:
+	temp = porta_lines(s);
+	s->pctra = mem_value;
+	s->portdira = portdir(mem_value);
+	s->portpullupa = portpullup(mem_value);
+	porta_changed(s, temp);
+	return;
+    case SH7750_PCTRB_A7:
+	temp = portb_lines(s);
+	s->pctrb = mem_value;
+	s->portdirb = portdir(mem_value);
+	s->portpullupb = portpullup(mem_value);
+	portb_changed(s, temp);
+	return;
+    case SH7750_TCNT0_A7:
+	s->tcnt0 = mem_value & 0xf;
+	return;
+    case SH7750_MMUCR_A7:
+	s->cpu->mmucr = mem_value;
+	return;
+    case SH7750_PTEH_A7:
+	s->cpu->pteh = mem_value;
+	return;
+    case SH7750_PTEL_A7:
+	s->cpu->ptel = mem_value;
+	return;
+    case SH7750_TTB_A7:
+	s->cpu->ttb = mem_value;
+	return;
+    case SH7750_TEA_A7:
+	s->cpu->tea = mem_value;
+	return;
+    case SH7750_TRA_A7:
+	s->cpu->tra = mem_value & 0x000007ff;
+	return;
+    case SH7750_EXPEVT_A7:
+	s->cpu->expevt = mem_value & 0x000007ff;
+	return;
+    case SH7750_INTEVT_A7:
+	s->cpu->intevt = mem_value & 0x000007ff;
+	return;
+    case SH7750_CCR_A7:
+	s->ccr = mem_value;
+	return;
+    default:
+	error_access("long write", addr);
+	assert(0);
+    }
+}
+
+static CPUReadMemoryFunc *sh7750_mem_read[] = {
+    sh7750_mem_readb,
+    sh7750_mem_readw,
+    sh7750_mem_readl
+};
+
+static CPUWriteMemoryFunc *sh7750_mem_write[] = {
+    sh7750_mem_writeb,
+    sh7750_mem_writew,
+    sh7750_mem_writel
+};
+
+SH7750State *sh7750_init(CPUSH4State * cpu)
+{
+    SH7750State *s;
+    int sh7750_io_memory;
+
+    s = qemu_mallocz(sizeof(SH7750State));
+    s->cpu = cpu;
+    s->periph_freq = 60000000;	/* 60MHz */
+    sh7750_io_memory = cpu_register_io_memory(0,
+					      sh7750_mem_read,
+					      sh7750_mem_write, s);
+    cpu_register_physical_memory(0x1c000000, 0x04000000, sh7750_io_memory);
+    init_timers(s);
+    init_serial_ports(s);
+    return s;
+}