ShuriZma
/
xemu
mirror of https://github.com/xemu-project/xemu.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

fdc: Disentangle phases in fdctrl_read_data() 

This commit makes similar improvements as have already been made to the
write function: Instead of relying on a flag in the MSR to distinguish
controller phases, use the explicit phase that we store now. Assertions
of the right MSR flags are added.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1432214378-31891-7-git-send-email-kwolf@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This commit is contained in:
Kevin Wolf 2015-05-21 15:19:36 +02:00 committed by John Snow
parent d275b33d76
commit f6c2d1d842
1 changed files with 23 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
hw/block/fdc.c
View File

@ -1591,9 +1591,16 @@ static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
FLOPPY_DPRINTF("error: controller not ready for reading\n"); FLOPPY_DPRINTF("error: controller not ready for reading\n");
return 0; return 0;
} }
/* If data_len spans multiple sectors, the current position in the FIFO
* wraps around while fdctrl->data_pos is the real position in the whole
* request. */
pos = fdctrl->data_pos; pos = fdctrl->data_pos;
pos %= FD_SECTOR_LEN; pos %= FD_SECTOR_LEN;
if (fdctrl->msr & FD_MSR_NONDMA) {
switch (fdctrl->phase) {
case FD_PHASE_EXECUTION:
assert(fdctrl->msr & FD_MSR_NONDMA);
if (pos == 0) { if (pos == 0) {
if (fdctrl->data_pos != 0) if (fdctrl->data_pos != 0)
if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) { if (!fdctrl_seek_to_next_sect(fdctrl, cur_drv)) {
@ -1609,20 +1616,26 @@ static uint32_t fdctrl_read_data(FDCtrl *fdctrl)
memset(fdctrl->fifo, 0, FD_SECTOR_LEN); memset(fdctrl->fifo, 0, FD_SECTOR_LEN);
} }
} }
}
retval = fdctrl->fifo[pos];
if (++fdctrl->data_pos == fdctrl->data_len) { if (++fdctrl->data_pos == fdctrl->data_len) {
fdctrl->data_pos = 0;
/* Switch from transfer mode to status mode
* then from status mode to command mode
*/
if (fdctrl->msr & FD_MSR_NONDMA) {
fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00); fdctrl_stop_transfer(fdctrl, 0x00, 0x00, 0x00);
} else { }
break;
case FD_PHASE_RESULT:
assert(!(fdctrl->msr & FD_MSR_NONDMA));
if (++fdctrl->data_pos == fdctrl->data_len) {
fdctrl_to_command_phase(fdctrl); fdctrl_to_command_phase(fdctrl);
fdctrl_reset_irq(fdctrl); fdctrl_reset_irq(fdctrl);
} }
break;
case FD_PHASE_COMMAND:
default:
abort();
} }
retval = fdctrl->fifo[pos];
FLOPPY_DPRINTF("data register: 0x%02x\n", retval); FLOPPY_DPRINTF("data register: 0x%02x\n", retval);
return retval; return retval;