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xemu/hw/esp.c
Paolo Bonzini 0d3545e76c scsi: add channel to addressing 
This also requires little more than adding the new argument to
scsi_device_find, and the qdev property.  All devices by default
end up on channel 0.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-28 19:25:51 +02:00

770 lines
20 KiB
C
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/*
* QEMU ESP/NCR53C9x emulation
*
* Copyright (c) 2005-2006 Fabrice Bellard
*
* 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 "sysbus.h"
#include "scsi.h"
#include "esp.h"
#include "trace.h"
/*
* On Sparc32, this is the ESP (NCR53C90) part of chip STP2000 (Master I/O),
* also produced as NCR89C100. See
* http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR89C100.txt
* and
* http://www.ibiblio.org/pub/historic-linux/early-ports/Sparc/NCR/NCR53C9X.txt
*/
#define ESP_ERROR(fmt, ...) \
do { printf("ESP ERROR: %s: " fmt, __func__ , ## __VA_ARGS__); } while (0)
#define ESP_REGS 16
#define TI_BUFSZ 16
typedef struct ESPState ESPState;
struct ESPState {
SysBusDevice busdev;
uint8_t rregs[ESP_REGS];
uint8_t wregs[ESP_REGS];
qemu_irq irq;
uint32_t it_shift;
int32_t ti_size;
uint32_t ti_rptr, ti_wptr;
uint32_t status;
uint32_t dma;
uint8_t ti_buf[TI_BUFSZ];
SCSIBus bus;
SCSIDevice *current_dev;
SCSIRequest *current_req;
uint8_t cmdbuf[TI_BUFSZ];
uint32_t cmdlen;
uint32_t do_cmd;
/* The amount of data left in the current DMA transfer. */
uint32_t dma_left;
/* The size of the current DMA transfer. Zero if no transfer is in
progress. */
uint32_t dma_counter;
int dma_enabled;
uint32_t async_len;
uint8_t *async_buf;
ESPDMAMemoryReadWriteFunc dma_memory_read;
ESPDMAMemoryReadWriteFunc dma_memory_write;
void *dma_opaque;
void (*dma_cb)(ESPState *s);
};
#define ESP_TCLO 0x0
#define ESP_TCMID 0x1
#define ESP_FIFO 0x2
#define ESP_CMD 0x3
#define ESP_RSTAT 0x4
#define ESP_WBUSID 0x4
#define ESP_RINTR 0x5
#define ESP_WSEL 0x5
#define ESP_RSEQ 0x6
#define ESP_WSYNTP 0x6
#define ESP_RFLAGS 0x7
#define ESP_WSYNO 0x7
#define ESP_CFG1 0x8
#define ESP_RRES1 0x9
#define ESP_WCCF 0x9
#define ESP_RRES2 0xa
#define ESP_WTEST 0xa
#define ESP_CFG2 0xb
#define ESP_CFG3 0xc
#define ESP_RES3 0xd
#define ESP_TCHI 0xe
#define ESP_RES4 0xf
#define CMD_DMA 0x80
#define CMD_CMD 0x7f
#define CMD_NOP 0x00
#define CMD_FLUSH 0x01
#define CMD_RESET 0x02
#define CMD_BUSRESET 0x03
#define CMD_TI 0x10
#define CMD_ICCS 0x11
#define CMD_MSGACC 0x12
#define CMD_PAD 0x18
#define CMD_SATN 0x1a
#define CMD_SEL 0x41
#define CMD_SELATN 0x42
#define CMD_SELATNS 0x43
#define CMD_ENSEL 0x44
#define STAT_DO 0x00
#define STAT_DI 0x01
#define STAT_CD 0x02
#define STAT_ST 0x03
#define STAT_MO 0x06
#define STAT_MI 0x07
#define STAT_PIO_MASK 0x06
#define STAT_TC 0x10
#define STAT_PE 0x20
#define STAT_GE 0x40
#define STAT_INT 0x80
#define BUSID_DID 0x07
#define INTR_FC 0x08
#define INTR_BS 0x10
#define INTR_DC 0x20
#define INTR_RST 0x80
#define SEQ_0 0x0
#define SEQ_CD 0x4
#define CFG1_RESREPT 0x40
#define TCHI_FAS100A 0x4
static void esp_raise_irq(ESPState *s)
{
if (!(s->rregs[ESP_RSTAT] & STAT_INT)) {
s->rregs[ESP_RSTAT] |= STAT_INT;
qemu_irq_raise(s->irq);
trace_esp_raise_irq();
}
}
static void esp_lower_irq(ESPState *s)
{
if (s->rregs[ESP_RSTAT] & STAT_INT) {
s->rregs[ESP_RSTAT] &= ~STAT_INT;
qemu_irq_lower(s->irq);
trace_esp_lower_irq();
}
}
static void esp_dma_enable(void *opaque, int irq, int level)
{
DeviceState *d = opaque;
ESPState *s = container_of(d, ESPState, busdev.qdev);
if (level) {
s->dma_enabled = 1;
trace_esp_dma_enable();
if (s->dma_cb) {
s->dma_cb(s);
s->dma_cb = NULL;
}
} else {
trace_esp_dma_disable();
s->dma_enabled = 0;
}
}
static void esp_request_cancelled(SCSIRequest *req)
{
ESPState *s = DO_UPCAST(ESPState, busdev.qdev, req->bus->qbus.parent);
if (req == s->current_req) {
scsi_req_unref(s->current_req);
s->current_req = NULL;
s->current_dev = NULL;
}
}
static uint32_t get_cmd(ESPState *s, uint8_t *buf)
{
uint32_t dmalen;
int target;
target = s->wregs[ESP_WBUSID] & BUSID_DID;
if (s->dma) {
dmalen = s->rregs[ESP_TCLO] | (s->rregs[ESP_TCMID] << 8);
s->dma_memory_read(s->dma_opaque, buf, dmalen);
} else {
dmalen = s->ti_size;
memcpy(buf, s->ti_buf, dmalen);
buf[0] = buf[2] >> 5;
}
trace_esp_get_cmd(dmalen, target);
s->ti_size = 0;
s->ti_rptr = 0;
s->ti_wptr = 0;
if (s->current_req) {
/* Started a new command before the old one finished. Cancel it. */
scsi_req_cancel(s->current_req);
s->async_len = 0;
}
s->current_dev = scsi_device_find(&s->bus, 0, target, 0);
if (!s->current_dev) {
// No such drive
s->rregs[ESP_RSTAT] = 0;
s->rregs[ESP_RINTR] = INTR_DC;
s->rregs[ESP_RSEQ] = SEQ_0;
esp_raise_irq(s);
return 0;
}
return dmalen;
}
static void do_busid_cmd(ESPState *s, uint8_t *buf, uint8_t busid)
{
int32_t datalen;
int lun;
SCSIDevice *current_lun;
trace_esp_do_busid_cmd(busid);
lun = busid & 7;
current_lun = scsi_device_find(&s->bus, 0, s->current_dev->id, lun);
s->current_req = scsi_req_new(current_lun, 0, lun, buf, NULL);
datalen = scsi_req_enqueue(s->current_req);
s->ti_size = datalen;
if (datalen != 0) {
s->rregs[ESP_RSTAT] = STAT_TC;
s->dma_left = 0;
s->dma_counter = 0;
if (datalen > 0) {
s->rregs[ESP_RSTAT] |= STAT_DI;
} else {
s->rregs[ESP_RSTAT] |= STAT_DO;
}
scsi_req_continue(s->current_req);
}
s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
s->rregs[ESP_RSEQ] = SEQ_CD;
esp_raise_irq(s);
}
static void do_cmd(ESPState *s, uint8_t *buf)
{
uint8_t busid = buf[0];
do_busid_cmd(s, &buf[1], busid);
}
static void handle_satn(ESPState *s)
{
uint8_t buf[32];
int len;
if (!s->dma_enabled) {
s->dma_cb = handle_satn;
return;
}
len = get_cmd(s, buf);
if (len)
do_cmd(s, buf);
}
static void handle_s_without_atn(ESPState *s)
{
uint8_t buf[32];
int len;
if (!s->dma_enabled) {
s->dma_cb = handle_s_without_atn;
return;
}
len = get_cmd(s, buf);
if (len) {
do_busid_cmd(s, buf, 0);
}
}
static void handle_satn_stop(ESPState *s)
{
if (!s->dma_enabled) {
s->dma_cb = handle_satn_stop;
return;
}
s->cmdlen = get_cmd(s, s->cmdbuf);
if (s->cmdlen) {
trace_esp_handle_satn_stop(s->cmdlen);
s->do_cmd = 1;
s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
s->rregs[ESP_RSEQ] = SEQ_CD;
esp_raise_irq(s);
}
}
static void write_response(ESPState *s)
{
trace_esp_write_response(s->status);
s->ti_buf[0] = s->status;
s->ti_buf[1] = 0;
if (s->dma) {
s->dma_memory_write(s->dma_opaque, s->ti_buf, 2);
s->rregs[ESP_RSTAT] = STAT_TC | STAT_ST;
s->rregs[ESP_RINTR] = INTR_BS | INTR_FC;
s->rregs[ESP_RSEQ] = SEQ_CD;
} else {
s->ti_size = 2;
s->ti_rptr = 0;
s->ti_wptr = 0;
s->rregs[ESP_RFLAGS] = 2;
}
esp_raise_irq(s);
}
static void esp_dma_done(ESPState *s)
{
s->rregs[ESP_RSTAT] |= STAT_TC;
s->rregs[ESP_RINTR] = INTR_BS;
s->rregs[ESP_RSEQ] = 0;
s->rregs[ESP_RFLAGS] = 0;
s->rregs[ESP_TCLO] = 0;
s->rregs[ESP_TCMID] = 0;
esp_raise_irq(s);
}
static void esp_do_dma(ESPState *s)
{
uint32_t len;
int to_device;
to_device = (s->ti_size < 0);
len = s->dma_left;
if (s->do_cmd) {
trace_esp_do_dma(s->cmdlen, len);
s->dma_memory_read(s->dma_opaque, &s->cmdbuf[s->cmdlen], len);
s->ti_size = 0;
s->cmdlen = 0;
s->do_cmd = 0;
do_cmd(s, s->cmdbuf);
return;
}
if (s->async_len == 0) {
/* Defer until data is available. */
return;
}
if (len > s->async_len) {
len = s->async_len;
}
if (to_device) {
s->dma_memory_read(s->dma_opaque, s->async_buf, len);
} else {
s->dma_memory_write(s->dma_opaque, s->async_buf, len);
}
s->dma_left -= len;
s->async_buf += len;
s->async_len -= len;
if (to_device)
s->ti_size += len;
else
s->ti_size -= len;
if (s->async_len == 0) {
scsi_req_continue(s->current_req);
/* If there is still data to be read from the device then
complete the DMA operation immediately. Otherwise defer
until the scsi layer has completed. */
if (to_device || s->dma_left != 0 || s->ti_size == 0) {
return;
}
}
/* Partially filled a scsi buffer. Complete immediately. */
esp_dma_done(s);
}
static void esp_command_complete(SCSIRequest *req, uint32_t status)
{
ESPState *s = DO_UPCAST(ESPState, busdev.qdev, req->bus->qbus.parent);
trace_esp_command_complete();
if (s->ti_size != 0) {
trace_esp_command_complete_unexpected();
}
s->ti_size = 0;
s->dma_left = 0;
s->async_len = 0;
if (status) {
trace_esp_command_complete_fail();
}
s->status = status;
s->rregs[ESP_RSTAT] = STAT_ST;
esp_dma_done(s);
if (s->current_req) {
scsi_req_unref(s->current_req);
s->current_req = NULL;
s->current_dev = NULL;
}
}
static void esp_transfer_data(SCSIRequest *req, uint32_t len)
{
ESPState *s = DO_UPCAST(ESPState, busdev.qdev, req->bus->qbus.parent);
trace_esp_transfer_data(s->dma_left, s->ti_size);
s->async_len = len;
s->async_buf = scsi_req_get_buf(req);
if (s->dma_left) {
esp_do_dma(s);
} else if (s->dma_counter != 0 && s->ti_size <= 0) {
/* If this was the last part of a DMA transfer then the
completion interrupt is deferred to here. */
esp_dma_done(s);
}
}
static void handle_ti(ESPState *s)
{
uint32_t dmalen, minlen;
dmalen = s->rregs[ESP_TCLO] | (s->rregs[ESP_TCMID] << 8);
if (dmalen==0) {
dmalen=0x10000;
}
s->dma_counter = dmalen;
if (s->do_cmd)
minlen = (dmalen < 32) ? dmalen : 32;
else if (s->ti_size < 0)
minlen = (dmalen < -s->ti_size) ? dmalen : -s->ti_size;
else
minlen = (dmalen < s->ti_size) ? dmalen : s->ti_size;
trace_esp_handle_ti(minlen);
if (s->dma) {
s->dma_left = minlen;
s->rregs[ESP_RSTAT] &= ~STAT_TC;
esp_do_dma(s);
} else if (s->do_cmd) {
trace_esp_handle_ti_cmd(s->cmdlen);
s->ti_size = 0;
s->cmdlen = 0;
s->do_cmd = 0;
do_cmd(s, s->cmdbuf);
return;
}
}
static void esp_hard_reset(DeviceState *d)
{
ESPState *s = container_of(d, ESPState, busdev.qdev);
memset(s->rregs, 0, ESP_REGS);
memset(s->wregs, 0, ESP_REGS);
s->rregs[ESP_TCHI] = TCHI_FAS100A; // Indicate fas100a
s->ti_size = 0;
s->ti_rptr = 0;
s->ti_wptr = 0;
s->dma = 0;
s->do_cmd = 0;
s->dma_cb = NULL;
s->rregs[ESP_CFG1] = 7;
}
static void esp_soft_reset(DeviceState *d)
{
ESPState *s = container_of(d, ESPState, busdev.qdev);
qemu_irq_lower(s->irq);
esp_hard_reset(d);
}
static void parent_esp_reset(void *opaque, int irq, int level)
{
if (level) {
esp_soft_reset(opaque);
}
}
static void esp_gpio_demux(void *opaque, int irq, int level)
{
switch (irq) {
case 0:
parent_esp_reset(opaque, irq, level);
break;
case 1:
esp_dma_enable(opaque, irq, level);
break;
}
}
static uint32_t esp_mem_readb(void *opaque, target_phys_addr_t addr)
{
ESPState *s = opaque;
uint32_t saddr, old_val;
saddr = addr >> s->it_shift;
trace_esp_mem_readb(saddr, s->rregs[saddr]);
switch (saddr) {
case ESP_FIFO:
if (s->ti_size > 0) {
s->ti_size--;
if ((s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
/* Data out. */
ESP_ERROR("PIO data read not implemented\n");
s->rregs[ESP_FIFO] = 0;
} else {
s->rregs[ESP_FIFO] = s->ti_buf[s->ti_rptr++];
}
esp_raise_irq(s);
}
if (s->ti_size == 0) {
s->ti_rptr = 0;
s->ti_wptr = 0;
}
break;
case ESP_RINTR:
/* Clear sequence step, interrupt register and all status bits
except TC */
old_val = s->rregs[ESP_RINTR];
s->rregs[ESP_RINTR] = 0;
s->rregs[ESP_RSTAT] &= ~STAT_TC;
s->rregs[ESP_RSEQ] = SEQ_CD;
esp_lower_irq(s);
return old_val;
default:
break;
}
return s->rregs[saddr];
}
static void esp_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)
{
ESPState *s = opaque;
uint32_t saddr;
saddr = addr >> s->it_shift;
trace_esp_mem_writeb(saddr, s->wregs[saddr], val);
switch (saddr) {
case ESP_TCLO:
case ESP_TCMID:
s->rregs[ESP_RSTAT] &= ~STAT_TC;
break;
case ESP_FIFO:
if (s->do_cmd) {
s->cmdbuf[s->cmdlen++] = val & 0xff;
} else if (s->ti_size == TI_BUFSZ - 1) {
ESP_ERROR("fifo overrun\n");
} else {
s->ti_size++;
s->ti_buf[s->ti_wptr++] = val & 0xff;
}
break;
case ESP_CMD:
s->rregs[saddr] = val;
if (val & CMD_DMA) {
s->dma = 1;
/* Reload DMA counter. */
s->rregs[ESP_TCLO] = s->wregs[ESP_TCLO];
s->rregs[ESP_TCMID] = s->wregs[ESP_TCMID];
} else {
s->dma = 0;
}
switch(val & CMD_CMD) {
case CMD_NOP:
trace_esp_mem_writeb_cmd_nop(val);
break;
case CMD_FLUSH:
trace_esp_mem_writeb_cmd_flush(val);
//s->ti_size = 0;
s->rregs[ESP_RINTR] = INTR_FC;
s->rregs[ESP_RSEQ] = 0;
s->rregs[ESP_RFLAGS] = 0;
break;
case CMD_RESET:
trace_esp_mem_writeb_cmd_reset(val);
esp_soft_reset(&s->busdev.qdev);
break;
case CMD_BUSRESET:
trace_esp_mem_writeb_cmd_bus_reset(val);
s->rregs[ESP_RINTR] = INTR_RST;
if (!(s->wregs[ESP_CFG1] & CFG1_RESREPT)) {
esp_raise_irq(s);
}
break;
case CMD_TI:
handle_ti(s);
break;
case CMD_ICCS:
trace_esp_mem_writeb_cmd_iccs(val);
write_response(s);
s->rregs[ESP_RINTR] = INTR_FC;
s->rregs[ESP_RSTAT] |= STAT_MI;
break;
case CMD_MSGACC:
trace_esp_mem_writeb_cmd_msgacc(val);
s->rregs[ESP_RINTR] = INTR_DC;
s->rregs[ESP_RSEQ] = 0;
s->rregs[ESP_RFLAGS] = 0;
esp_raise_irq(s);
break;
case CMD_PAD:
trace_esp_mem_writeb_cmd_pad(val);
s->rregs[ESP_RSTAT] = STAT_TC;
s->rregs[ESP_RINTR] = INTR_FC;
s->rregs[ESP_RSEQ] = 0;
break;
case CMD_SATN:
trace_esp_mem_writeb_cmd_satn(val);
break;
case CMD_SEL:
trace_esp_mem_writeb_cmd_sel(val);
handle_s_without_atn(s);
break;
case CMD_SELATN:
trace_esp_mem_writeb_cmd_selatn(val);
handle_satn(s);
break;
case CMD_SELATNS:
trace_esp_mem_writeb_cmd_selatns(val);
handle_satn_stop(s);
break;
case CMD_ENSEL:
trace_esp_mem_writeb_cmd_ensel(val);
s->rregs[ESP_RINTR] = 0;
break;
default:
ESP_ERROR("Unhandled ESP command (%2.2x)\n", val);
break;
}
break;
case ESP_WBUSID ... ESP_WSYNO:
break;
case ESP_CFG1:
s->rregs[saddr] = val;
break;
case ESP_WCCF ... ESP_WTEST:
break;
case ESP_CFG2 ... ESP_RES4:
s->rregs[saddr] = val;
break;
default:
ESP_ERROR("invalid write of 0x%02x at [0x%x]\n", val, saddr);
return;
}
s->wregs[saddr] = val;
}
static CPUReadMemoryFunc * const esp_mem_read[3] = {
esp_mem_readb,
NULL,
NULL,
};
static CPUWriteMemoryFunc * const esp_mem_write[3] = {
esp_mem_writeb,
NULL,
esp_mem_writeb,
};
static const VMStateDescription vmstate_esp = {
.name ="esp",
.version_id = 3,
.minimum_version_id = 3,
.minimum_version_id_old = 3,
.fields = (VMStateField []) {
VMSTATE_BUFFER(rregs, ESPState),
VMSTATE_BUFFER(wregs, ESPState),
VMSTATE_INT32(ti_size, ESPState),
VMSTATE_UINT32(ti_rptr, ESPState),
VMSTATE_UINT32(ti_wptr, ESPState),
VMSTATE_BUFFER(ti_buf, ESPState),
VMSTATE_UINT32(status, ESPState),
VMSTATE_UINT32(dma, ESPState),
VMSTATE_BUFFER(cmdbuf, ESPState),
VMSTATE_UINT32(cmdlen, ESPState),
VMSTATE_UINT32(do_cmd, ESPState),
VMSTATE_UINT32(dma_left, ESPState),
VMSTATE_END_OF_LIST()
}
};
void esp_init(target_phys_addr_t espaddr, int it_shift,
ESPDMAMemoryReadWriteFunc dma_memory_read,
ESPDMAMemoryReadWriteFunc dma_memory_write,
void *dma_opaque, qemu_irq irq, qemu_irq *reset,
qemu_irq *dma_enable)
{
DeviceState *dev;
SysBusDevice *s;
ESPState *esp;
dev = qdev_create(NULL, "esp");
esp = DO_UPCAST(ESPState, busdev.qdev, dev);
esp->dma_memory_read = dma_memory_read;
esp->dma_memory_write = dma_memory_write;
esp->dma_opaque = dma_opaque;
esp->it_shift = it_shift;
/* XXX for now until rc4030 has been changed to use DMA enable signal */
esp->dma_enabled = 1;
qdev_init_nofail(dev);
s = sysbus_from_qdev(dev);
sysbus_connect_irq(s, 0, irq);
sysbus_mmio_map(s, 0, espaddr);
*reset = qdev_get_gpio_in(dev, 0);
*dma_enable = qdev_get_gpio_in(dev, 1);
}
static const struct SCSIBusInfo esp_scsi_info = {
.tcq = false,
.max_target = ESP_MAX_DEVS,
.max_lun = 7,
.transfer_data = esp_transfer_data,
.complete = esp_command_complete,
.cancel = esp_request_cancelled
};
static int esp_init1(SysBusDevice *dev)
{
ESPState *s = FROM_SYSBUS(ESPState, dev);
int esp_io_memory;
sysbus_init_irq(dev, &s->irq);
assert(s->it_shift != -1);
esp_io_memory = cpu_register_io_memory(esp_mem_read, esp_mem_write, s,
DEVICE_NATIVE_ENDIAN);
sysbus_init_mmio(dev, ESP_REGS << s->it_shift, esp_io_memory);
qdev_init_gpio_in(&dev->qdev, esp_gpio_demux, 2);
scsi_bus_new(&s->bus, &dev->qdev, &esp_scsi_info);
return scsi_bus_legacy_handle_cmdline(&s->bus);
}
static SysBusDeviceInfo esp_info = {
.init = esp_init1,
.qdev.name = "esp",
.qdev.size = sizeof(ESPState),
.qdev.vmsd = &vmstate_esp,
.qdev.reset = esp_hard_reset,
.qdev.props = (Property[]) {
{.name = NULL}
}
};
static void esp_register_devices(void)
{
sysbus_register_withprop(&esp_info);
}
device_init(esp_register_devices)
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