[qemu.git] / hw / sd / milkymist-memcard.c

/*
 *  QEMU model of the Milkymist SD Card Controller.
 *
 *  Copyright (c) 2010 Michael Walle <[email protected]>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 *
 * Specification available at:
 *   http://www.milkymist.org/socdoc/memcard.pdf
 */

#include "hw/hw.h"
#include "hw/sysbus.h"
#include "sysemu/sysemu.h"
#include "trace.h"
#include "qemu/error-report.h"
#include "sysemu/block-backend.h"
#include "sysemu/blockdev.h"
#include "hw/sd.h"

enum {
    ENABLE_CMD_TX   = (1<<0),
    ENABLE_CMD_RX   = (1<<1),
    ENABLE_DAT_TX   = (1<<2),
    ENABLE_DAT_RX   = (1<<3),
};

enum {
    PENDING_CMD_TX   = (1<<0),
    PENDING_CMD_RX   = (1<<1),
    PENDING_DAT_TX   = (1<<2),
    PENDING_DAT_RX   = (1<<3),
};

enum {
    START_CMD_TX    = (1<<0),
    START_DAT_RX    = (1<<1),
};

enum {
    R_CLK2XDIV = 0,
    R_ENABLE,
    R_PENDING,
    R_START,
    R_CMD,
    R_DAT,
    R_MAX
};

#define TYPE_MILKYMIST_MEMCARD "milkymist-memcard"
#define MILKYMIST_MEMCARD(obj) \
    OBJECT_CHECK(MilkymistMemcardState, (obj), TYPE_MILKYMIST_MEMCARD)

struct MilkymistMemcardState {
    SysBusDevice parent_obj;

    MemoryRegion regs_region;
    SDState *card;

    int command_write_ptr;
    int response_read_ptr;
    int response_len;
    int ignore_next_cmd;
    int enabled;
    uint8_t command[6];
    uint8_t response[17];
    uint32_t regs[R_MAX];
};
typedef struct MilkymistMemcardState MilkymistMemcardState;

static void update_pending_bits(MilkymistMemcardState *s)
{
    /* transmits are instantaneous, thus tx pending bits are never set */
    s->regs[R_PENDING] = 0;
    /* if rx is enabled the corresponding pending bits are always set */
    if (s->regs[R_ENABLE] & ENABLE_CMD_RX) {
        s->regs[R_PENDING] |= PENDING_CMD_RX;
    }
    if (s->regs[R_ENABLE] & ENABLE_DAT_RX) {
        s->regs[R_PENDING] |= PENDING_DAT_RX;
    }
}

static void memcard_sd_command(MilkymistMemcardState *s)
{
    SDRequest req;

    req.cmd = s->command[0] & 0x3f;
    req.arg = (s->command[1] << 24) | (s->command[2] << 16)
              | (s->command[3] << 8) | s->command[4];
    req.crc = s->command[5];

    s->response[0] = req.cmd;
    s->response_len = sd_do_command(s->card, &req, s->response+1);
    s->response_read_ptr = 0;

    if (s->response_len == 16) {
        /* R2 response */
        s->response[0] = 0x3f;
        s->response_len += 1;
    } else if (s->response_len == 4) {
        /* no crc calculation, insert dummy byte */
        s->response[5] = 0;
        s->response_len += 2;
    }

    if (req.cmd == 0) {
        /* next write is a dummy byte to clock the initialization of the sd
         * card */
        s->ignore_next_cmd = 1;
    }
}

static uint64_t memcard_read(void *opaque, hwaddr addr,
                             unsigned size)
{
    MilkymistMemcardState *s = opaque;
    uint32_t r = 0;

    addr >>= 2;
    switch (addr) {
    case R_CMD:
        if (!s->enabled) {
            r = 0xff;
        } else {
            r = s->response[s->response_read_ptr++];
            if (s->response_read_ptr > s->response_len) {
                error_report("milkymist_memcard: "
                        "read more cmd bytes than available. Clipping.");
                s->response_read_ptr = 0;
            }
        }
        break;
    case R_DAT:
        if (!s->enabled) {
            r = 0xffffffff;
        } else {
            r = 0;
            r |= sd_read_data(s->card) << 24;
            r |= sd_read_data(s->card) << 16;
            r |= sd_read_data(s->card) << 8;
            r |= sd_read_data(s->card);
        }
        break;
    case R_CLK2XDIV:
    case R_ENABLE:
    case R_PENDING:
    case R_START:
        r = s->regs[addr];
        break;

    default:
        error_report("milkymist_memcard: read access to unknown register 0x"
                TARGET_FMT_plx, addr << 2);
        break;
    }

    trace_milkymist_memcard_memory_read(addr << 2, r);

    return r;
}

static void memcard_write(void *opaque, hwaddr addr, uint64_t value,
                          unsigned size)
{
    MilkymistMemcardState *s = opaque;

    trace_milkymist_memcard_memory_write(addr, value);

    addr >>= 2;
    switch (addr) {
    case R_PENDING:
        /* clear rx pending bits */
        s->regs[R_PENDING] &= ~(value & (PENDING_CMD_RX | PENDING_DAT_RX));
        update_pending_bits(s);
        break;
    case R_CMD:
        if (!s->enabled) {
            break;
        }
        if (s->ignore_next_cmd) {
            s->ignore_next_cmd = 0;
            break;
        }
        s->command[s->command_write_ptr] = value & 0xff;
        s->command_write_ptr = (s->command_write_ptr + 1) % 6;
        if (s->command_write_ptr == 0) {
            memcard_sd_command(s);
        }
        break;
    case R_DAT:
        if (!s->enabled) {
            break;
        }
        sd_write_data(s->card, (value >> 24) & 0xff);
        sd_write_data(s->card, (value >> 16) & 0xff);
        sd_write_data(s->card, (value >> 8) & 0xff);
        sd_write_data(s->card, value & 0xff);
        break;
    case R_ENABLE:
        s->regs[addr] = value;
        update_pending_bits(s);
        break;
    case R_CLK2XDIV:
    case R_START:
        s->regs[addr] = value;
        break;

    default:
        error_report("milkymist_memcard: write access to unknown register 0x"
                TARGET_FMT_plx, addr << 2);
        break;
    }
}

static const MemoryRegionOps memcard_mmio_ops = {
    .read = memcard_read,
    .write = memcard_write,
    .valid = {
        .min_access_size = 4,
        .max_access_size = 4,
    },
    .endianness = DEVICE_NATIVE_ENDIAN,
};

static void milkymist_memcard_reset(DeviceState *d)
{
    MilkymistMemcardState *s = MILKYMIST_MEMCARD(d);
    int i;

    s->command_write_ptr = 0;
    s->response_read_ptr = 0;
    s->response_len = 0;

    for (i = 0; i < R_MAX; i++) {
        s->regs[i] = 0;
    }
}

static int milkymist_memcard_init(SysBusDevice *dev)
{
    MilkymistMemcardState *s = MILKYMIST_MEMCARD(dev);
    DriveInfo *dinfo;
    BlockDriverState *bs;

    dinfo = drive_get_next(IF_SD);
    bs = dinfo ? blk_bs(blk_by_legacy_dinfo(dinfo)) : NULL;
    s->card = sd_init(bs, false);
    if (s->card == NULL) {
        return -1;
    }

    s->enabled = bs && bdrv_is_inserted(bs);

    memory_region_init_io(&s->regs_region, OBJECT(s), &memcard_mmio_ops, s,
            "milkymist-memcard", R_MAX * 4);
    sysbus_init_mmio(dev, &s->regs_region);

    return 0;
}

static const VMStateDescription vmstate_milkymist_memcard = {
    .name = "milkymist-memcard",
    .version_id = 1,
    .minimum_version_id = 1,
    .fields = (VMStateField[]) {
        VMSTATE_INT32(command_write_ptr, MilkymistMemcardState),
        VMSTATE_INT32(response_read_ptr, MilkymistMemcardState),
        VMSTATE_INT32(response_len, MilkymistMemcardState),
        VMSTATE_INT32(ignore_next_cmd, MilkymistMemcardState),
        VMSTATE_INT32(enabled, MilkymistMemcardState),
        VMSTATE_UINT8_ARRAY(command, MilkymistMemcardState, 6),
        VMSTATE_UINT8_ARRAY(response, MilkymistMemcardState, 17),
        VMSTATE_UINT32_ARRAY(regs, MilkymistMemcardState, R_MAX),
        VMSTATE_END_OF_LIST()
    }
};

static void milkymist_memcard_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);
    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);

    k->init = milkymist_memcard_init;
    dc->reset = milkymist_memcard_reset;
    dc->vmsd = &vmstate_milkymist_memcard;
}

static const TypeInfo milkymist_memcard_info = {
    .name          = TYPE_MILKYMIST_MEMCARD,
    .parent        = TYPE_SYS_BUS_DEVICE,
    .instance_size = sizeof(MilkymistMemcardState),
    .class_init    = milkymist_memcard_class_init,
};

static void milkymist_memcard_register_types(void)
{
    type_register_static(&milkymist_memcard_info);
}

type_init(milkymist_memcard_register_types)
Commit	Line	Data
b4e37d98 MW	1	/*
	2	* QEMU model of the Milkymist SD Card Controller.
	3	*
	4	* Copyright (c) 2010 Michael Walle <[email protected]>
	5	*
	6	* This library is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU Lesser General Public
	8	* License as published by the Free Software Foundation; either
	9	* version 2 of the License, or (at your option) any later version.
	10	*
	11	* This library is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* Lesser General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU Lesser General Public
	17	* License along with this library; if not, see <http://www.gnu.org/licenses/>.
	18	*
	19	*
	20	* Specification available at:
	21	* http://www.milkymist.org/socdoc/memcard.pdf
	22	*/
	23
83c9f4ca PB	24	#include "hw/hw.h"
83c9f4ca PB	25	#include "hw/sysbus.h"
9c17d615	26	#include "sysemu/sysemu.h"
b4e37d98	27	#include "trace.h"
1de7afc9	28	#include "qemu/error-report.h"
fa1d36df	29	#include "sysemu/block-backend.h"
9c17d615	30	#include "sysemu/blockdev.h"
83c9f4ca	31	#include "hw/sd.h"
b4e37d98 MW	32
	33	enum {
	34	ENABLE_CMD_TX = (1<<0),
	35	ENABLE_CMD_RX = (1<<1),
	36	ENABLE_DAT_TX = (1<<2),
	37	ENABLE_DAT_RX = (1<<3),
	38	};
	39
	40	enum {
	41	PENDING_CMD_TX = (1<<0),
	42	PENDING_CMD_RX = (1<<1),
	43	PENDING_DAT_TX = (1<<2),
	44	PENDING_DAT_RX = (1<<3),
	45	};
	46
	47	enum {
	48	START_CMD_TX = (1<<0),
	49	START_DAT_RX = (1<<1),
	50	};
	51
	52	enum {
	53	R_CLK2XDIV = 0,
	54	R_ENABLE,
	55	R_PENDING,
	56	R_START,
	57	R_CMD,
	58	R_DAT,
	59	R_MAX
	60	};
	61
7a239e46 AF	62	#define TYPE_MILKYMIST_MEMCARD "milkymist-memcard"
	63	#define MILKYMIST_MEMCARD(obj) \
	64	OBJECT_CHECK(MilkymistMemcardState, (obj), TYPE_MILKYMIST_MEMCARD)
	65
b4e37d98	66	struct MilkymistMemcardState {
7a239e46 AF	67	SysBusDevice parent_obj;
7a239e46 AF	68
8c85d15b	69	MemoryRegion regs_region;
b4e37d98 MW	70	SDState *card;
	71
	72	int command_write_ptr;
	73	int response_read_ptr;
	74	int response_len;
	75	int ignore_next_cmd;
	76	int enabled;
	77	uint8_t command[6];
	78	uint8_t response[17];
	79	uint32_t regs[R_MAX];
	80	};
	81	typedef struct MilkymistMemcardState MilkymistMemcardState;
	82
	83	static void update_pending_bits(MilkymistMemcardState *s)
	84	{
	85	/* transmits are instantaneous, thus tx pending bits are never set */
	86	s->regs[R_PENDING] = 0;
	87	/* if rx is enabled the corresponding pending bits are always set */
	88	if (s->regs[R_ENABLE] & ENABLE_CMD_RX) {
	89	s->regs[R_PENDING] \|= PENDING_CMD_RX;
	90	}
	91	if (s->regs[R_ENABLE] & ENABLE_DAT_RX) {
	92	s->regs[R_PENDING] \|= PENDING_DAT_RX;
	93	}
	94	}
	95
	96	static void memcard_sd_command(MilkymistMemcardState *s)
	97	{
	98	SDRequest req;
	99
	100	req.cmd = s->command[0] & 0x3f;
	101	req.arg = (s->command[1] << 24) \| (s->command[2] << 16)
	102	\| (s->command[3] << 8) \| s->command[4];
	103	req.crc = s->command[5];
	104
	105	s->response[0] = req.cmd;
	106	s->response_len = sd_do_command(s->card, &req, s->response+1);
	107	s->response_read_ptr = 0;
	108
	109	if (s->response_len == 16) {
	110	/* R2 response */
	111	s->response[0] = 0x3f;
	112	s->response_len += 1;
	113	} else if (s->response_len == 4) {
	114	/* no crc calculation, insert dummy byte */
	115	s->response[5] = 0;
	116	s->response_len += 2;
	117	}
	118
	119	if (req.cmd == 0) {
	120	/* next write is a dummy byte to clock the initialization of the sd
	121	* card */
	122	s->ignore_next_cmd = 1;
	123	}
	124	}
	125
a8170e5e	126	static uint64_t memcard_read(void *opaque, hwaddr addr,
8c85d15b	127	unsigned size)
b4e37d98 MW	128	{
	129	MilkymistMemcardState *s = opaque;
	130	uint32_t r = 0;
	131
	132	addr >>= 2;
	133	switch (addr) {
	134	case R_CMD:
	135	if (!s->enabled) {
	136	r = 0xff;
	137	} else {
	138	r = s->response[s->response_read_ptr++];
	139	if (s->response_read_ptr > s->response_len) {
	140	error_report("milkymist_memcard: "
	141	"read more cmd bytes than available. Clipping.");
	142	s->response_read_ptr = 0;
	143	}
	144	}
	145	break;
	146	case R_DAT:
	147	if (!s->enabled) {
	148	r = 0xffffffff;
	149	} else {
	150	r = 0;
	151	r \|= sd_read_data(s->card) << 24;
	152	r \|= sd_read_data(s->card) << 16;
	153	r \|= sd_read_data(s->card) << 8;
	154	r \|= sd_read_data(s->card);
	155	}
	156	break;
	157	case R_CLK2XDIV:
	158	case R_ENABLE:
	159	case R_PENDING:
	160	case R_START:
	161	r = s->regs[addr];
	162	break;
	163
	164	default:
dd3d6775	165	error_report("milkymist_memcard: read access to unknown register 0x"
b4e37d98 MW	166	TARGET_FMT_plx, addr << 2);
	167	break;
	168	}
	169
	170	trace_milkymist_memcard_memory_read(addr << 2, r);
	171
	172	return r;
	173	}
	174
a8170e5e	175	static void memcard_write(void *opaque, hwaddr addr, uint64_t value,
8c85d15b	176	unsigned size)
b4e37d98 MW	177	{
	178	MilkymistMemcardState *s = opaque;
	179
	180	trace_milkymist_memcard_memory_write(addr, value);
	181
	182	addr >>= 2;
	183	switch (addr) {
	184	case R_PENDING:
	185	/* clear rx pending bits */
	186	s->regs[R_PENDING] &= ~(value & (PENDING_CMD_RX \| PENDING_DAT_RX));
	187	update_pending_bits(s);
	188	break;
	189	case R_CMD:
	190	if (!s->enabled) {
	191	break;
	192	}
	193	if (s->ignore_next_cmd) {
	194	s->ignore_next_cmd = 0;
	195	break;
	196	}
	197	s->command[s->command_write_ptr] = value & 0xff;
	198	s->command_write_ptr = (s->command_write_ptr + 1) % 6;
	199	if (s->command_write_ptr == 0) {
	200	memcard_sd_command(s);
	201	}
	202	break;
	203	case R_DAT:
	204	if (!s->enabled) {
	205	break;
	206	}
	207	sd_write_data(s->card, (value >> 24) & 0xff);
	208	sd_write_data(s->card, (value >> 16) & 0xff);
	209	sd_write_data(s->card, (value >> 8) & 0xff);
	210	sd_write_data(s->card, value & 0xff);
	211	break;
	212	case R_ENABLE:
	213	s->regs[addr] = value;
	214	update_pending_bits(s);
	215	break;
	216	case R_CLK2XDIV:
	217	case R_START:
	218	s->regs[addr] = value;
	219	break;
	220
	221	default:
dd3d6775	222	error_report("milkymist_memcard: write access to unknown register 0x"
b4e37d98 MW	223	TARGET_FMT_plx, addr << 2);
	224	break;
	225	}
	226	}
	227
8c85d15b MW	228	static const MemoryRegionOps memcard_mmio_ops = {
	229	.read = memcard_read,
	230	.write = memcard_write,
	231	.valid = {
	232	.min_access_size = 4,
	233	.max_access_size = 4,
	234	},
	235	.endianness = DEVICE_NATIVE_ENDIAN,
b4e37d98 MW	236	};
	237
	238	static void milkymist_memcard_reset(DeviceState *d)
	239	{
7a239e46	240	MilkymistMemcardState *s = MILKYMIST_MEMCARD(d);
b4e37d98 MW	241	int i;
	242
	243	s->command_write_ptr = 0;
	244	s->response_read_ptr = 0;
	245	s->response_len = 0;
	246
	247	for (i = 0; i < R_MAX; i++) {
	248	s->regs[i] = 0;
	249	}
	250	}
	251
	252	static int milkymist_memcard_init(SysBusDevice *dev)
	253	{
7a239e46	254	MilkymistMemcardState *s = MILKYMIST_MEMCARD(dev);
b4e37d98	255	DriveInfo *dinfo;
fa1d36df	256	BlockDriverState *bs;
b4e37d98 MW	257
b4e37d98 MW	258	dinfo = drive_get_next(IF_SD);
fa1d36df MA	259	bs = dinfo ? blk_bs(blk_by_legacy_dinfo(dinfo)) : NULL;
fa1d36df MA	260	s->card = sd_init(bs, false);
4f8a066b KW	261	if (s->card == NULL) {
	262	return -1;
	263	}
	264
fa1d36df	265	s->enabled = bs && bdrv_is_inserted(bs);
b4e37d98	266
29776739	267	memory_region_init_io(&s->regs_region, OBJECT(s), &memcard_mmio_ops, s,
8c85d15b	268	"milkymist-memcard", R_MAX * 4);
750ecd44	269	sysbus_init_mmio(dev, &s->regs_region);
b4e37d98 MW	270
	271	return 0;
	272	}
	273
	274	static const VMStateDescription vmstate_milkymist_memcard = {
	275	.name = "milkymist-memcard",
	276	.version_id = 1,
	277	.minimum_version_id = 1,
35d08458	278	.fields = (VMStateField[]) {
b4e37d98 MW	279	VMSTATE_INT32(command_write_ptr, MilkymistMemcardState),
	280	VMSTATE_INT32(response_read_ptr, MilkymistMemcardState),
	281	VMSTATE_INT32(response_len, MilkymistMemcardState),
	282	VMSTATE_INT32(ignore_next_cmd, MilkymistMemcardState),
	283	VMSTATE_INT32(enabled, MilkymistMemcardState),
	284	VMSTATE_UINT8_ARRAY(command, MilkymistMemcardState, 6),
	285	VMSTATE_UINT8_ARRAY(response, MilkymistMemcardState, 17),
	286	VMSTATE_UINT32_ARRAY(regs, MilkymistMemcardState, R_MAX),
	287	VMSTATE_END_OF_LIST()
	288	}
	289	};
	290
999e12bb AL	291	static void milkymist_memcard_class_init(ObjectClass klass, void data)
999e12bb AL	292	{
39bffca2	293	DeviceClass *dc = DEVICE_CLASS(klass);
999e12bb AL	294	SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
	295
	296	k->init = milkymist_memcard_init;
39bffca2 AL	297	dc->reset = milkymist_memcard_reset;
39bffca2 AL	298	dc->vmsd = &vmstate_milkymist_memcard;
999e12bb AL	299	}
999e12bb AL	300
8c43a6f0	301	static const TypeInfo milkymist_memcard_info = {
7a239e46	302	.name = TYPE_MILKYMIST_MEMCARD,
39bffca2 AL	303	.parent = TYPE_SYS_BUS_DEVICE,
	304	.instance_size = sizeof(MilkymistMemcardState),
	305	.class_init = milkymist_memcard_class_init,
b4e37d98 MW	306	};
b4e37d98 MW	307
83f7d43a	308	static void milkymist_memcard_register_types(void)
b4e37d98	309	{
39bffca2	310	type_register_static(&milkymist_memcard_info);
b4e37d98 MW	311	}
b4e37d98 MW	312
83f7d43a	313	type_init(milkymist_memcard_register_types)