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esp: implement non-DMA transfers in PDMA mode

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The MacOS toolbox ROM uses non-DMA TI commands to handle the first/last byte
of an unaligned 16-bit transfer to memory.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210304221103.6369-42-mark.cave-ayland@ilande.co.uk>
This commit is contained in:
Mark Cave-Ayland 2021-03-04 22:11:02 +00:00
parent 238ec4d7d4
commit 1b9e48a5bd
2 changed files with 98 additions and 36 deletions
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133
hw/scsi/esp.c
View File

@ -296,6 +296,7 @@ static void do_busid_cmd(ESPState *s, uint8_t busid)
if (datalen != 0) {
s->rregs[ESP_RSTAT] = STAT_TC;
s->rregs[ESP_RSEQ] = SEQ_CD;
s->ti_cmd = 0;
esp_set_tc(s, 0);
if (datalen > 0) {
/*
@ -645,6 +646,71 @@ static void esp_do_dma(ESPState *s)
esp_lower_drq(s);
}
static void esp_do_nodma(ESPState *s)
{
int to_device = ((s->rregs[ESP_RSTAT] & 7) == STAT_DO);
uint32_t cmdlen, n;
int len;
if (s->do_cmd) {
cmdlen = fifo8_num_used(&s->cmdfifo);
trace_esp_handle_ti_cmd(cmdlen);
s->ti_size = 0;
if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
/* No command received */
if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
return;
}
/* Command has been received */
s->do_cmd = 0;
do_cmd(s);
} else {
/*
* Extra message out bytes received: update cmdfifo_cdb_offset
* and then switch to commmand phase
*/
s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
s->rregs[ESP_RSEQ] = SEQ_CD;
s->rregs[ESP_RINTR] |= INTR_BS;
esp_raise_irq(s);
}
return;
}
if (s->async_len == 0) {
/* Defer until data is available. */
return;
}
if (to_device) {
len = MIN(fifo8_num_used(&s->fifo), ESP_FIFO_SZ);
memcpy(s->async_buf, fifo8_pop_buf(&s->fifo, len, &n), len);
s->async_buf += len;
s->async_len -= len;
s->ti_size += len;
} else {
len = MIN(s->ti_size, s->async_len);
len = MIN(len, fifo8_num_free(&s->fifo));
fifo8_push_all(&s->fifo, s->async_buf, len);
s->async_buf += len;
s->async_len -= len;
s->ti_size -= len;
}
if (s->async_len == 0) {
scsi_req_continue(s->current_req);
if (to_device || s->ti_size == 0) {
return;
}
}
s->rregs[ESP_RINTR] |= INTR_BS;
esp_raise_irq(s);
}
void esp_command_complete(SCSIRequest *req, size_t resid)
{
ESPState *s = req->hba_private;
@ -701,56 +767,51 @@ void esp_transfer_data(SCSIRequest *req, uint32_t len)
return;
}
if (dmalen) {
esp_do_dma(s);
} else if (s->ti_size <= 0) {
if (s->ti_cmd == 0) {
/*
* If this was the last part of a DMA transfer then the
* completion interrupt is deferred to here.
* Always perform the initial transfer upon reception of the next TI
* command to ensure the DMA/non-DMA status of the command is correct.
* It is not possible to use s->dma directly in the section below as
* some OSs send non-DMA NOP commands after a DMA transfer. Hence if the
* async data transfer is delayed then s->dma is set incorrectly.
*/
esp_dma_done(s);
esp_lower_drq(s);
return;
}
if (s->ti_cmd & CMD_DMA) {
if (dmalen) {
esp_do_dma(s);
} else if (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);
esp_lower_drq(s);
}
} else {
esp_do_nodma(s);
}
}
static void handle_ti(ESPState *s)
{
uint32_t dmalen, cmdlen;
uint32_t dmalen;
if (s->dma && !s->dma_enabled) {
s->dma_cb = handle_ti;
return;
}
dmalen = esp_get_tc(s);
s->ti_cmd = s->rregs[ESP_CMD];
if (s->dma) {
dmalen = esp_get_tc(s);
trace_esp_handle_ti(dmalen);
s->rregs[ESP_RSTAT] &= ~STAT_TC;
esp_do_dma(s);
} else if (s->do_cmd) {
cmdlen = fifo8_num_used(&s->cmdfifo);
trace_esp_handle_ti_cmd(cmdlen);
s->ti_size = 0;
if ((s->rregs[ESP_RSTAT] & 7) == STAT_CD) {
/* No command received */
if (s->cmdfifo_cdb_offset == fifo8_num_used(&s->cmdfifo)) {
return;
}
/* Command has been received */
s->do_cmd = 0;
do_cmd(s);
} else {
/*
* Extra message out bytes received: update cmdfifo_cdb_offset
* and then switch to commmand phase
*/
s->cmdfifo_cdb_offset = fifo8_num_used(&s->cmdfifo);
s->rregs[ESP_RSTAT] = STAT_TC | STAT_CD;
s->rregs[ESP_RSEQ] = SEQ_CD;
s->rregs[ESP_RINTR] |= INTR_BS;
esp_raise_irq(s);
}
} else {
trace_esp_handle_ti(s->ti_size);
esp_do_nodma(s);
}
}
@ -789,12 +850,12 @@ uint64_t esp_reg_read(ESPState *s, uint32_t saddr)
switch (saddr) {
case ESP_FIFO:
if ((s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
if (s->dma_memory_read && s->dma_memory_write &&
(s->rregs[ESP_RSTAT] & STAT_PIO_MASK) == 0) {
/* Data out. */
qemu_log_mask(LOG_UNIMP, "esp: PIO data read not implemented\n");
s->rregs[ESP_FIFO] = 0;
} else {
s->ti_size--;
s->rregs[ESP_FIFO] = esp_fifo_pop(s);
}
val = s->rregs[ESP_FIFO];
@ -846,7 +907,6 @@ void esp_reg_write(ESPState *s, uint32_t saddr, uint64_t val)
if (s->do_cmd) {
esp_cmdfifo_push(s, val);
} else {
s->ti_size++;
esp_fifo_push(s, val);
}
@ -1047,6 +1107,7 @@ const VMStateDescription vmstate_esp = {
VMSTATE_UINT8_TEST(cmdfifo_cdb_offset, ESPState, esp_is_version_5),
VMSTATE_FIFO8_TEST(fifo, ESPState, esp_is_version_5),
VMSTATE_FIFO8_TEST(cmdfifo, ESPState, esp_is_version_5),
VMSTATE_UINT8_TEST(ti_cmd, ESPState, esp_is_version_5),
VMSTATE_END_OF_LIST()
},
};

1
include/hw/scsi/esp.h
View File

@ -40,6 +40,7 @@ struct ESPState {
uint32_t do_cmd;
bool data_in_ready;
uint8_t ti_cmd;
int dma_enabled;
uint32_t async_len;