q800: fix mac_via RTC PRAM commands

The command byte is not decoded correctly.

This patch reworks the RTC/PRAM interface and fixes the problem.
It adds a comment before the function to explain how are encoded commands
and some trace-events to ease debugging.

Bug: https://bugs.launchpad.net/qemu/+bug/1856549
Fixes: 6dca62a000 ("hw/m68k: add VIA support")
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20191219201439.84804-2-laurent@vivier.eu>
This commit is contained in:
Laurent Vivier 2019-12-19 21:14:38 +01:00
parent cdbc5c51c8
commit b2619c158a
2 changed files with 210 additions and 83 deletions

View File

@ -27,7 +27,7 @@
#include "sysemu/runstate.h"
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "trace.h"
/*
* VIAs: There are two in every machine,
@ -278,6 +278,21 @@
/* VIA returns time offset from Jan 1, 1904, not 1970 */
#define RTC_OFFSET 2082844800
enum {
REG_0,
REG_1,
REG_2,
REG_3,
REG_TEST,
REG_WPROTECT,
REG_PRAM_ADDR,
REG_PRAM_ADDR_LAST = REG_PRAM_ADDR + 19,
REG_PRAM_SECT,
REG_PRAM_SECT_LAST = REG_PRAM_SECT + 7,
REG_INVALID,
REG_EMPTY = 0xff,
};
static void via1_VBL_update(MOS6522Q800VIA1State *v1s)
{
MOS6522State *s = MOS6522(v1s);
@ -360,10 +375,62 @@ static void via2_irq_request(void *opaque, int irq, int level)
mdc->update_irq(s);
}
/*
* RTC Commands
*
* Command byte Register addressed by the command
*
* z0000001 Seconds register 0 (lowest-order byte)
* z0000101 Seconds register 1
* z0001001 Seconds register 2
* z0001101 Seconds register 3 (highest-order byte)
* 00110001 Test register (write-only)
* 00110101 Write-Protect Register (write-only)
* z010aa01 RAM address 100aa ($10-$13) (first 20 bytes only)
* z1aaaa01 RAM address 0aaaa ($00-$0F) (first 20 bytes only)
* z0111aaa Extended memory designator and sector number
*
* For a read request, z=1, for a write z=0
* The letter a indicates bits whose value depend on what parameter
* RAM byte you want to address
*/
static int via1_rtc_compact_cmd(uint8_t value)
{
uint8_t read = value & 0x80;
value &= 0x7f;
/* the last 2 bits of a command byte must always be 0b01 ... */
if ((value & 0x78) == 0x38) {
/* except for the extended memory designator */
return read | (REG_PRAM_SECT + (value & 0x07));
}
if ((value & 0x03) == 0x01) {
value >>= 2;
if ((value & 0x1c) == 0) {
/* seconds registers */
return read | (REG_0 + (value & 0x03));
} else if ((value == 0x0c) && !read) {
return REG_TEST;
} else if ((value == 0x0d) && !read) {
return REG_WPROTECT;
} else if ((value & 0x1c) == 0x08) {
/* RAM address 0x10 to 0x13 */
return read | (REG_PRAM_ADDR + 0x10 + (value & 0x03));
} else if ((value & 0x43) == 0x41) {
/* RAM address 0x00 to 0x0f */
return read | (REG_PRAM_ADDR + (value & 0x0f));
}
}
return REG_INVALID;
}
static void via1_rtc_update(MacVIAState *m)
{
MOS6522Q800VIA1State *v1s = &m->mos6522_via1;
MOS6522State *s = MOS6522(v1s);
int cmd, sector, addr;
uint32_t time;
if (s->b & VIA1B_vRTCEnb) {
return;
@ -376,7 +443,9 @@ static void via1_rtc_update(MacVIAState *m)
m->data_out |= s->b & VIA1B_vRTCData;
m->data_out_cnt++;
}
trace_via1_rtc_update_data_out(m->data_out_cnt, m->data_out);
} else {
trace_via1_rtc_update_data_in(m->data_in_cnt, m->data_in);
/* receive bits from the RTC */
if ((v1s->last_b & VIA1B_vRTCClk) &&
!(s->b & VIA1B_vRTCClk) &&
@ -386,96 +455,132 @@ static void via1_rtc_update(MacVIAState *m)
m->data_in <<= 1;
m->data_in_cnt--;
}
return;
}
if (m->data_out_cnt == 8) {
m->data_out_cnt = 0;
if (m->data_out_cnt != 8) {
return;
}
if (m->cmd == 0) {
if (m->data_out & 0x80) {
/* this is a read command */
uint32_t time = m->tick_offset +
(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) /
NANOSECONDS_PER_SECOND);
if (m->data_out == 0x81) { /* seconds register 0 */
m->data_in = time & 0xff;
m->data_in_cnt = 8;
} else if (m->data_out == 0x85) { /* seconds register 1 */
m->data_in = (time >> 8) & 0xff;
m->data_in_cnt = 8;
} else if (m->data_out == 0x89) { /* seconds register 2 */
m->data_in = (time >> 16) & 0xff;
m->data_in_cnt = 8;
} else if (m->data_out == 0x8d) { /* seconds register 3 */
m->data_in = (time >> 24) & 0xff;
m->data_in_cnt = 8;
} else if ((m->data_out & 0xf3) == 0xa1) {
/* PRAM address 0x10 -> 0x13 */
int addr = (m->data_out >> 2) & 0x03;
m->data_in = v1s->PRAM[addr];
m->data_in_cnt = 8;
} else if ((m->data_out & 0xf3) == 0xa1) {
/* PRAM address 0x00 -> 0x0f */
int addr = (m->data_out >> 2) & 0x0f;
m->data_in = v1s->PRAM[addr];
m->data_in_cnt = 8;
} else if ((m->data_out & 0xf8) == 0xb8) {
/* extended memory designator and sector number */
m->cmd = m->data_out;
}
} else {
/* this is a write command */
m->cmd = m->data_out;
}
} else {
if (m->cmd & 0x80) {
if ((m->cmd & 0xf8) == 0xb8) {
/* extended memory designator and sector number */
int sector = m->cmd & 0x07;
int addr = (m->data_out >> 2) & 0x1f;
m->data_out_cnt = 0;
m->data_in = v1s->PRAM[sector * 8 + addr];
m->data_in_cnt = 8;
}
} else if (!m->wprotect) {
/* this is a write command */
if (m->alt != 0) {
/* extended memory designator and sector number */
int sector = m->cmd & 0x07;
int addr = (m->alt >> 2) & 0x1f;
trace_via1_rtc_internal_status(m->cmd, m->alt, m->data_out);
/* first byte: it's a command */
if (m->cmd == REG_EMPTY) {
v1s->PRAM[sector * 8 + addr] = m->data_out;
cmd = via1_rtc_compact_cmd(m->data_out);
trace_via1_rtc_internal_cmd(cmd);
m->alt = 0;
} else if (m->cmd == 0x01) { /* seconds register 0 */
/* FIXME */
} else if (m->cmd == 0x05) { /* seconds register 1 */
/* FIXME */
} else if (m->cmd == 0x09) { /* seconds register 2 */
/* FIXME */
} else if (m->cmd == 0x0d) { /* seconds register 3 */
/* FIXME */
} else if (m->cmd == 0x31) {
/* Test Register */
} else if (m->cmd == 0x35) {
/* Write Protect register */
m->wprotect = m->data_out & 1;
} else if ((m->cmd & 0xf3) == 0xa1) {
/* PRAM address 0x10 -> 0x13 */
int addr = (m->cmd >> 2) & 0x03;
v1s->PRAM[addr] = m->data_out;
} else if ((m->cmd & 0xf3) == 0xa1) {
/* PRAM address 0x00 -> 0x0f */
int addr = (m->cmd >> 2) & 0x0f;
v1s->PRAM[addr] = m->data_out;
} else if ((m->cmd & 0xf8) == 0xb8) {
/* extended memory designator and sector number */
m->alt = m->cmd;
}
}
if (cmd == REG_INVALID) {
trace_via1_rtc_cmd_invalid(m->data_out);
return;
}
m->data_out = 0;
if (cmd & 0x80) { /* this is a read command */
switch (cmd & 0x7f) {
case REG_0...REG_3: /* seconds registers */
/*
* register 0 is lowest-order byte
* register 3 is highest-order byte
*/
time = m->tick_offset + (qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)
/ NANOSECONDS_PER_SECOND);
trace_via1_rtc_internal_time(time);
m->data_in = (time >> ((cmd & 0x03) << 3)) & 0xff;
m->data_in_cnt = 8;
trace_via1_rtc_cmd_seconds_read((cmd & 0x7f) - REG_0,
m->data_in);
break;
case REG_PRAM_ADDR...REG_PRAM_ADDR_LAST:
/* PRAM address 0x00 -> 0x13 */
m->data_in = v1s->PRAM[(cmd & 0x7f) - REG_PRAM_ADDR];
m->data_in_cnt = 8;
trace_via1_rtc_cmd_pram_read((cmd & 0x7f) - REG_PRAM_ADDR,
m->data_in);
break;
case REG_PRAM_SECT...REG_PRAM_SECT_LAST:
/*
* extended memory designator and sector number
* the only two-byte read command
*/
trace_via1_rtc_internal_set_cmd(cmd);
m->cmd = cmd;
break;
default:
g_assert_not_reached();
break;
}
return;
}
/* this is a write command, needs a parameter */
if (cmd == REG_WPROTECT || !m->wprotect) {
trace_via1_rtc_internal_set_cmd(cmd);
m->cmd = cmd;
} else {
trace_via1_rtc_internal_ignore_cmd(cmd);
}
return;
}
/* second byte: it's a parameter */
if (m->alt == REG_EMPTY) {
switch (m->cmd & 0x7f) {
case REG_0...REG_3: /* seconds register */
/* FIXME */
trace_via1_rtc_cmd_seconds_write(m->cmd - REG_0, m->data_out);
m->cmd = REG_EMPTY;
break;
case REG_TEST:
/* device control: nothing to do */
trace_via1_rtc_cmd_test_write(m->data_out);
m->cmd = REG_EMPTY;
break;
case REG_WPROTECT:
/* Write Protect register */
trace_via1_rtc_cmd_wprotect_write(m->data_out);
m->wprotect = !!(m->data_out & 0x80);
m->cmd = REG_EMPTY;
break;
case REG_PRAM_ADDR...REG_PRAM_ADDR_LAST:
/* PRAM address 0x00 -> 0x13 */
trace_via1_rtc_cmd_pram_write(m->cmd - REG_PRAM_ADDR, m->data_out);
v1s->PRAM[m->cmd - REG_PRAM_ADDR] = m->data_out;
m->cmd = REG_EMPTY;
break;
case REG_PRAM_SECT...REG_PRAM_SECT_LAST:
addr = (m->data_out >> 2) & 0x1f;
sector = (m->cmd & 0x7f) - REG_PRAM_SECT;
if (m->cmd & 0x80) {
/* it's a read */
m->data_in = v1s->PRAM[sector * 32 + addr];
m->data_in_cnt = 8;
trace_via1_rtc_cmd_pram_sect_read(sector, addr,
sector * 32 + addr,
m->data_in);
m->cmd = REG_EMPTY;
} else {
/* it's a write, we need one more parameter */
trace_via1_rtc_internal_set_alt(addr, sector, addr);
m->alt = addr;
}
break;
default:
g_assert_not_reached();
break;
}
return;
}
/* third byte: it's the data of a REG_PRAM_SECT write */
g_assert(REG_PRAM_SECT <= m->cmd && m->cmd <= REG_PRAM_SECT_LAST);
sector = m->cmd - REG_PRAM_SECT;
v1s->PRAM[sector * 32 + m->alt] = m->data_out;
trace_via1_rtc_cmd_pram_sect_write(sector, m->alt, sector * 32 + m->alt,
m->data_out);
m->alt = REG_EMPTY;
m->cmd = REG_EMPTY;
}
static int adb_via_poll(MacVIAState *s, int state, uint8_t *data)
@ -742,6 +847,9 @@ static void mac_via_reset(DeviceState *dev)
v1s->next_VBL = 0;
timer_del(v1s->one_second_timer);
v1s->next_second = 0;
m->cmd = REG_EMPTY;
m->alt = REG_EMPTY;
}
static void mac_via_realize(DeviceState *dev, Error **errp)

View File

@ -149,3 +149,22 @@ bcm2835_mbox_write(unsigned int size, uint64_t addr, uint64_t value) "mbox write
bcm2835_mbox_read(unsigned int size, uint64_t addr, uint64_t value) "mbox read sz:%u addr:0x%"PRIx64" data:0x%"PRIx64
bcm2835_mbox_irq(unsigned level) "mbox irq:ARM level:%u"
bcm2835_mbox_property(uint32_t tag, uint32_t bufsize, size_t resplen) "mbox property tag:0x%08x in_sz:%u out_sz:%zu"
# mac_via.c
via1_rtc_update_data_out(int count, int value) "count=%d value=0x%02x"
via1_rtc_update_data_in(int count, int value) "count=%d value=0x%02x"
via1_rtc_internal_status(int cmd, int alt, int value) "cmd=0x%02x alt=0x%02x value=0x%02x"
via1_rtc_internal_cmd(int cmd) "cmd=0x%02x"
via1_rtc_cmd_invalid(int value) "value=0x%02x"
via1_rtc_internal_time(uint32_t time) "time=0x%08x"
via1_rtc_internal_set_cmd(int cmd) "cmd=0x%02x"
via1_rtc_internal_ignore_cmd(int cmd) "cmd=0x%02x"
via1_rtc_internal_set_alt(int alt, int sector, int offset) "alt=0x%02x sector=%u offset=%u"
via1_rtc_cmd_seconds_read(int reg, int value) "reg=%d value=0x%02x"
via1_rtc_cmd_seconds_write(int reg, int value) "reg=%d value=0x%02x"
via1_rtc_cmd_test_write(int value) "value=0x%02x"
via1_rtc_cmd_wprotect_write(int value) "value=0x%02x"
via1_rtc_cmd_pram_read(int addr, int value) "addr=%u value=0x%02x"
via1_rtc_cmd_pram_write(int addr, int value) "addr=%u value=0x%02x"
via1_rtc_cmd_pram_sect_read(int sector, int offset, int addr, int value) "sector=%u offset=%u addr=%d value=0x%02x"
via1_rtc_cmd_pram_sect_write(int sector, int offset, int addr, int value) "sector=%u offset=%u addr=%d value=0x%02x"