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qemu/hw/char/exynos4210_uart.c
Halil Pasic 59046ec29a migration: consolidate VMStateField.start 
The member VMStateField.start is used for two things, partial data
migration for VBUFFER data (basically provide migration for a
sub-buffer) and for locating next in QTAILQ.

The implementation of the VBUFFER feature is broken when VMSTATE_ALLOC
is used. This however goes unnoticed because actually partial migration
for VBUFFER is not used at all.

Let's consolidate the usage of VMStateField.start by removing support
for partial migration for VBUFFER.

Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>

Message-Id: <20170203175217.45562-1-pasic@linux.vnet.ibm.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-13 17:27:13 +00:00

682 lines
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/*
* Exynos4210 UART Emulation
*
* Copyright (C) 2011 Samsung Electronics Co Ltd.
* Maksim Kozlov, <m.kozlov@samsung.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, see <http://www.gnu.org/licenses/>.
*
*/
#include "qemu/osdep.h"
#include "hw/sysbus.h"
#include "qemu/error-report.h"
#include "sysemu/sysemu.h"
#include "sysemu/char.h"
#include "hw/arm/exynos4210.h"
#undef DEBUG_UART
#undef DEBUG_UART_EXTEND
#undef DEBUG_IRQ
#undef DEBUG_Rx_DATA
#undef DEBUG_Tx_DATA
#define DEBUG_UART 0
#define DEBUG_UART_EXTEND 0
#define DEBUG_IRQ 0
#define DEBUG_Rx_DATA 0
#define DEBUG_Tx_DATA 0
#if DEBUG_UART
#define PRINT_DEBUG(fmt, args...) \
do { \
fprintf(stderr, " [%s:%d] "fmt, __func__, __LINE__, ##args); \
} while (0)
#if DEBUG_UART_EXTEND
#define PRINT_DEBUG_EXTEND(fmt, args...) \
do { \
fprintf(stderr, " [%s:%d] "fmt, __func__, __LINE__, ##args); \
} while (0)
#else
#define PRINT_DEBUG_EXTEND(fmt, args...) \
do {} while (0)
#endif /* EXTEND */
#else
#define PRINT_DEBUG(fmt, args...) \
do {} while (0)
#define PRINT_DEBUG_EXTEND(fmt, args...) \
do {} while (0)
#endif
#define PRINT_ERROR(fmt, args...) \
do { \
fprintf(stderr, " [%s:%d] "fmt, __func__, __LINE__, ##args); \
} while (0)
/*
* Offsets for UART registers relative to SFR base address
* for UARTn
*
*/
#define ULCON 0x0000 /* Line Control */
#define UCON 0x0004 /* Control */
#define UFCON 0x0008 /* FIFO Control */
#define UMCON 0x000C /* Modem Control */
#define UTRSTAT 0x0010 /* Tx/Rx Status */
#define UERSTAT 0x0014 /* UART Error Status */
#define UFSTAT 0x0018 /* FIFO Status */
#define UMSTAT 0x001C /* Modem Status */
#define UTXH 0x0020 /* Transmit Buffer */
#define URXH 0x0024 /* Receive Buffer */
#define UBRDIV 0x0028 /* Baud Rate Divisor */
#define UFRACVAL 0x002C /* Divisor Fractional Value */
#define UINTP 0x0030 /* Interrupt Pending */
#define UINTSP 0x0034 /* Interrupt Source Pending */
#define UINTM 0x0038 /* Interrupt Mask */
/*
* for indexing register in the uint32_t array
*
* 'reg' - register offset (see offsets definitions above)
*
*/
#define I_(reg) (reg / sizeof(uint32_t))
typedef struct Exynos4210UartReg {
const char *name; /* the only reason is the debug output */
hwaddr offset;
uint32_t reset_value;
} Exynos4210UartReg;
static Exynos4210UartReg exynos4210_uart_regs[] = {
{"ULCON", ULCON, 0x00000000},
{"UCON", UCON, 0x00003000},
{"UFCON", UFCON, 0x00000000},
{"UMCON", UMCON, 0x00000000},
{"UTRSTAT", UTRSTAT, 0x00000006}, /* RO */
{"UERSTAT", UERSTAT, 0x00000000}, /* RO */
{"UFSTAT", UFSTAT, 0x00000000}, /* RO */
{"UMSTAT", UMSTAT, 0x00000000}, /* RO */
{"UTXH", UTXH, 0x5c5c5c5c}, /* WO, undefined reset value*/
{"URXH", URXH, 0x00000000}, /* RO */
{"UBRDIV", UBRDIV, 0x00000000},
{"UFRACVAL", UFRACVAL, 0x00000000},
{"UINTP", UINTP, 0x00000000},
{"UINTSP", UINTSP, 0x00000000},
{"UINTM", UINTM, 0x00000000},
};
#define EXYNOS4210_UART_REGS_MEM_SIZE 0x3C
/* UART FIFO Control */
#define UFCON_FIFO_ENABLE 0x1
#define UFCON_Rx_FIFO_RESET 0x2
#define UFCON_Tx_FIFO_RESET 0x4
#define UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT 8
#define UFCON_Tx_FIFO_TRIGGER_LEVEL (7 << UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT)
#define UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT 4
#define UFCON_Rx_FIFO_TRIGGER_LEVEL (7 << UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT)
/* Uart FIFO Status */
#define UFSTAT_Rx_FIFO_COUNT 0xff
#define UFSTAT_Rx_FIFO_FULL 0x100
#define UFSTAT_Rx_FIFO_ERROR 0x200
#define UFSTAT_Tx_FIFO_COUNT_SHIFT 16
#define UFSTAT_Tx_FIFO_COUNT (0xff << UFSTAT_Tx_FIFO_COUNT_SHIFT)
#define UFSTAT_Tx_FIFO_FULL_SHIFT 24
#define UFSTAT_Tx_FIFO_FULL (1 << UFSTAT_Tx_FIFO_FULL_SHIFT)
/* UART Interrupt Source Pending */
#define UINTSP_RXD 0x1 /* Receive interrupt */
#define UINTSP_ERROR 0x2 /* Error interrupt */
#define UINTSP_TXD 0x4 /* Transmit interrupt */
#define UINTSP_MODEM 0x8 /* Modem interrupt */
/* UART Line Control */
#define ULCON_IR_MODE_SHIFT 6
#define ULCON_PARITY_SHIFT 3
#define ULCON_STOP_BIT_SHIFT 1
/* UART Tx/Rx Status */
#define UTRSTAT_TRANSMITTER_EMPTY 0x4
#define UTRSTAT_Tx_BUFFER_EMPTY 0x2
#define UTRSTAT_Rx_BUFFER_DATA_READY 0x1
/* UART Error Status */
#define UERSTAT_OVERRUN 0x1
#define UERSTAT_PARITY 0x2
#define UERSTAT_FRAME 0x4
#define UERSTAT_BREAK 0x8
typedef struct {
uint8_t *data;
uint32_t sp, rp; /* store and retrieve pointers */
uint32_t size;
} Exynos4210UartFIFO;
#define TYPE_EXYNOS4210_UART "exynos4210.uart"
#define EXYNOS4210_UART(obj) \
OBJECT_CHECK(Exynos4210UartState, (obj), TYPE_EXYNOS4210_UART)
typedef struct Exynos4210UartState {
SysBusDevice parent_obj;
MemoryRegion iomem;
uint32_t reg[EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)];
Exynos4210UartFIFO rx;
Exynos4210UartFIFO tx;
CharBackend chr;
qemu_irq irq;
uint32_t channel;
} Exynos4210UartState;
#if DEBUG_UART
/* Used only for debugging inside PRINT_DEBUG_... macros */
static const char *exynos4210_uart_regname(hwaddr offset)
{
int i;
for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
if (offset == exynos4210_uart_regs[i].offset) {
return exynos4210_uart_regs[i].name;
}
}
return NULL;
}
#endif
static void fifo_store(Exynos4210UartFIFO *q, uint8_t ch)
{
q->data[q->sp] = ch;
q->sp = (q->sp + 1) % q->size;
}
static uint8_t fifo_retrieve(Exynos4210UartFIFO *q)
{
uint8_t ret = q->data[q->rp];
q->rp = (q->rp + 1) % q->size;
return ret;
}
static int fifo_elements_number(Exynos4210UartFIFO *q)
{
if (q->sp < q->rp) {
return q->size - q->rp + q->sp;
}
return q->sp - q->rp;
}
static int fifo_empty_elements_number(Exynos4210UartFIFO *q)
{
return q->size - fifo_elements_number(q);
}
static void fifo_reset(Exynos4210UartFIFO *q)
{
g_free(q->data);
q->data = NULL;
q->data = (uint8_t *)g_malloc0(q->size);
q->sp = 0;
q->rp = 0;
}
static uint32_t exynos4210_uart_Tx_FIFO_trigger_level(Exynos4210UartState *s)
{
uint32_t level = 0;
uint32_t reg;
reg = (s->reg[I_(UFCON)] & UFCON_Tx_FIFO_TRIGGER_LEVEL) >>
UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT;
switch (s->channel) {
case 0:
level = reg * 32;
break;
case 1:
case 4:
level = reg * 8;
break;
case 2:
case 3:
level = reg * 2;
break;
default:
level = 0;
PRINT_ERROR("Wrong UART channel number: %d\n", s->channel);
}
return level;
}
static void exynos4210_uart_update_irq(Exynos4210UartState *s)
{
/*
* The Tx interrupt is always requested if the number of data in the
* transmit FIFO is smaller than the trigger level.
*/
if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
uint32_t count = (s->reg[I_(UFSTAT)] & UFSTAT_Tx_FIFO_COUNT) >>
UFSTAT_Tx_FIFO_COUNT_SHIFT;
if (count <= exynos4210_uart_Tx_FIFO_trigger_level(s)) {
s->reg[I_(UINTSP)] |= UINTSP_TXD;
}
}
s->reg[I_(UINTP)] = s->reg[I_(UINTSP)] & ~s->reg[I_(UINTM)];
if (s->reg[I_(UINTP)]) {
qemu_irq_raise(s->irq);
#if DEBUG_IRQ
fprintf(stderr, "UART%d: IRQ has been raised: %08x\n",
s->channel, s->reg[I_(UINTP)]);
#endif
} else {
qemu_irq_lower(s->irq);
}
}
static void exynos4210_uart_update_parameters(Exynos4210UartState *s)
{
int speed, parity, data_bits, stop_bits;
QEMUSerialSetParams ssp;
uint64_t uclk_rate;
if (s->reg[I_(UBRDIV)] == 0) {
return;
}
if (s->reg[I_(ULCON)] & 0x20) {
if (s->reg[I_(ULCON)] & 0x28) {
parity = 'E';
} else {
parity = 'O';
}
} else {
parity = 'N';
}
if (s->reg[I_(ULCON)] & 0x4) {
stop_bits = 2;
} else {
stop_bits = 1;
}
data_bits = (s->reg[I_(ULCON)] & 0x3) + 5;
uclk_rate = 24000000;
speed = uclk_rate / ((16 * (s->reg[I_(UBRDIV)]) & 0xffff) +
(s->reg[I_(UFRACVAL)] & 0x7) + 16);
ssp.speed = speed;
ssp.parity = parity;
ssp.data_bits = data_bits;
ssp.stop_bits = stop_bits;
qemu_chr_fe_ioctl(&s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
PRINT_DEBUG("UART%d: speed: %d, parity: %c, data: %d, stop: %d\n",
s->channel, speed, parity, data_bits, stop_bits);
}
static void exynos4210_uart_write(void *opaque, hwaddr offset,
uint64_t val, unsigned size)
{
Exynos4210UartState *s = (Exynos4210UartState *)opaque;
uint8_t ch;
PRINT_DEBUG_EXTEND("UART%d: <0x%04x> %s <- 0x%08llx\n", s->channel,
offset, exynos4210_uart_regname(offset), (long long unsigned int)val);
switch (offset) {
case ULCON:
case UBRDIV:
case UFRACVAL:
s->reg[I_(offset)] = val;
exynos4210_uart_update_parameters(s);
break;
case UFCON:
s->reg[I_(UFCON)] = val;
if (val & UFCON_Rx_FIFO_RESET) {
fifo_reset(&s->rx);
s->reg[I_(UFCON)] &= ~UFCON_Rx_FIFO_RESET;
PRINT_DEBUG("UART%d: Rx FIFO Reset\n", s->channel);
}
if (val & UFCON_Tx_FIFO_RESET) {
fifo_reset(&s->tx);
s->reg[I_(UFCON)] &= ~UFCON_Tx_FIFO_RESET;
PRINT_DEBUG("UART%d: Tx FIFO Reset\n", s->channel);
}
break;
case UTXH:
if (qemu_chr_fe_get_driver(&s->chr)) {
s->reg[I_(UTRSTAT)] &= ~(UTRSTAT_TRANSMITTER_EMPTY |
UTRSTAT_Tx_BUFFER_EMPTY);
ch = (uint8_t)val;
/* XXX this blocks entire thread. Rewrite to use
* qemu_chr_fe_write and background I/O callbacks */
qemu_chr_fe_write_all(&s->chr, &ch, 1);
#if DEBUG_Tx_DATA
fprintf(stderr, "%c", ch);
#endif
s->reg[I_(UTRSTAT)] |= UTRSTAT_TRANSMITTER_EMPTY |
UTRSTAT_Tx_BUFFER_EMPTY;
s->reg[I_(UINTSP)] |= UINTSP_TXD;
exynos4210_uart_update_irq(s);
}
break;
case UINTP:
s->reg[I_(UINTP)] &= ~val;
s->reg[I_(UINTSP)] &= ~val;
PRINT_DEBUG("UART%d: UINTP [%04x] have been cleared: %08x\n",
s->channel, offset, s->reg[I_(UINTP)]);
exynos4210_uart_update_irq(s);
break;
case UTRSTAT:
case UERSTAT:
case UFSTAT:
case UMSTAT:
case URXH:
PRINT_DEBUG("UART%d: Trying to write into RO register: %s [%04x]\n",
s->channel, exynos4210_uart_regname(offset), offset);
break;
case UINTSP:
s->reg[I_(UINTSP)] &= ~val;
break;
case UINTM:
s->reg[I_(UINTM)] = val;
exynos4210_uart_update_irq(s);
break;
case UCON:
case UMCON:
default:
s->reg[I_(offset)] = val;
break;
}
}
static uint64_t exynos4210_uart_read(void *opaque, hwaddr offset,
unsigned size)
{
Exynos4210UartState *s = (Exynos4210UartState *)opaque;
uint32_t res;
switch (offset) {
case UERSTAT: /* Read Only */
res = s->reg[I_(UERSTAT)];
s->reg[I_(UERSTAT)] = 0;
return res;
case UFSTAT: /* Read Only */
s->reg[I_(UFSTAT)] = fifo_elements_number(&s->rx) & 0xff;
if (fifo_empty_elements_number(&s->rx) == 0) {
s->reg[I_(UFSTAT)] |= UFSTAT_Rx_FIFO_FULL;
s->reg[I_(UFSTAT)] &= ~0xff;
}
return s->reg[I_(UFSTAT)];
case URXH:
if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
if (fifo_elements_number(&s->rx)) {
res = fifo_retrieve(&s->rx);
#if DEBUG_Rx_DATA
fprintf(stderr, "%c", res);
#endif
if (!fifo_elements_number(&s->rx)) {
s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
} else {
s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
}
} else {
s->reg[I_(UINTSP)] |= UINTSP_ERROR;
exynos4210_uart_update_irq(s);
res = 0;
}
} else {
s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
res = s->reg[I_(URXH)];
}
return res;
case UTXH:
PRINT_DEBUG("UART%d: Trying to read from WO register: %s [%04x]\n",
s->channel, exynos4210_uart_regname(offset), offset);
break;
default:
return s->reg[I_(offset)];
}
return 0;
}
static const MemoryRegionOps exynos4210_uart_ops = {
.read = exynos4210_uart_read,
.write = exynos4210_uart_write,
.endianness = DEVICE_NATIVE_ENDIAN,
.valid = {
.max_access_size = 4,
.unaligned = false
},
};
static int exynos4210_uart_can_receive(void *opaque)
{
Exynos4210UartState *s = (Exynos4210UartState *)opaque;
return fifo_empty_elements_number(&s->rx);
}
static void exynos4210_uart_receive(void *opaque, const uint8_t *buf, int size)
{
Exynos4210UartState *s = (Exynos4210UartState *)opaque;
int i;
if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
if (fifo_empty_elements_number(&s->rx) < size) {
for (i = 0; i < fifo_empty_elements_number(&s->rx); i++) {
fifo_store(&s->rx, buf[i]);
}
s->reg[I_(UINTSP)] |= UINTSP_ERROR;
s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
} else {
for (i = 0; i < size; i++) {
fifo_store(&s->rx, buf[i]);
}
s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
}
/* XXX: Around here we maybe should check Rx trigger level */
s->reg[I_(UINTSP)] |= UINTSP_RXD;
} else {
s->reg[I_(URXH)] = buf[0];
s->reg[I_(UINTSP)] |= UINTSP_RXD;
s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
}
exynos4210_uart_update_irq(s);
}
static void exynos4210_uart_event(void *opaque, int event)
{
Exynos4210UartState *s = (Exynos4210UartState *)opaque;
if (event == CHR_EVENT_BREAK) {
/* When the RxDn is held in logic 0, then a null byte is pushed into the
* fifo */
fifo_store(&s->rx, '\0');
s->reg[I_(UERSTAT)] |= UERSTAT_BREAK;
exynos4210_uart_update_irq(s);
}
}
static void exynos4210_uart_reset(DeviceState *dev)
{
Exynos4210UartState *s = EXYNOS4210_UART(dev);
int i;
for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
s->reg[I_(exynos4210_uart_regs[i].offset)] =
exynos4210_uart_regs[i].reset_value;
}
fifo_reset(&s->rx);
fifo_reset(&s->tx);
PRINT_DEBUG("UART%d: Rx FIFO size: %d\n", s->channel, s->rx.size);
}
static const VMStateDescription vmstate_exynos4210_uart_fifo = {
.name = "exynos4210.uart.fifo",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_UINT32(sp, Exynos4210UartFIFO),
VMSTATE_UINT32(rp, Exynos4210UartFIFO),
VMSTATE_VBUFFER_UINT32(data, Exynos4210UartFIFO, 1, NULL, size),
VMSTATE_END_OF_LIST()
}
};
static const VMStateDescription vmstate_exynos4210_uart = {
.name = "exynos4210.uart",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_STRUCT(rx, Exynos4210UartState, 1,
vmstate_exynos4210_uart_fifo, Exynos4210UartFIFO),
VMSTATE_UINT32_ARRAY(reg, Exynos4210UartState,
EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)),
VMSTATE_END_OF_LIST()
}
};
DeviceState *exynos4210_uart_create(hwaddr addr,
int fifo_size,
int channel,
Chardev *chr,
qemu_irq irq)
{
DeviceState *dev;
SysBusDevice *bus;
const char chr_name[] = "serial";
char label[ARRAY_SIZE(chr_name) + 1];
dev = qdev_create(NULL, TYPE_EXYNOS4210_UART);
if (!chr) {
if (channel >= MAX_SERIAL_PORTS) {
error_report("Only %d serial ports are supported by QEMU",
MAX_SERIAL_PORTS);
exit(1);
}
chr = serial_hds[channel];
if (!chr) {
snprintf(label, ARRAY_SIZE(label), "%s%d", chr_name, channel);
chr = qemu_chr_new(label, "null");
if (!(chr)) {
error_report("Can't assign serial port to UART%d", channel);
exit(1);
}
}
}
qdev_prop_set_chr(dev, "chardev", chr);
qdev_prop_set_uint32(dev, "channel", channel);
qdev_prop_set_uint32(dev, "rx-size", fifo_size);
qdev_prop_set_uint32(dev, "tx-size", fifo_size);
bus = SYS_BUS_DEVICE(dev);
qdev_init_nofail(dev);
if (addr != (hwaddr)-1) {
sysbus_mmio_map(bus, 0, addr);
}
sysbus_connect_irq(bus, 0, irq);
return dev;
}
static void exynos4210_uart_init(Object *obj)
{
SysBusDevice *dev = SYS_BUS_DEVICE(obj);
Exynos4210UartState *s = EXYNOS4210_UART(dev);
/* memory mapping */
memory_region_init_io(&s->iomem, obj, &exynos4210_uart_ops, s,
"exynos4210.uart", EXYNOS4210_UART_REGS_MEM_SIZE);
sysbus_init_mmio(dev, &s->iomem);
sysbus_init_irq(dev, &s->irq);
}
static void exynos4210_uart_realize(DeviceState *dev, Error **errp)
{
Exynos4210UartState *s = EXYNOS4210_UART(dev);
qemu_chr_fe_set_handlers(&s->chr, exynos4210_uart_can_receive,
exynos4210_uart_receive, exynos4210_uart_event,
s, NULL, true);
}
static Property exynos4210_uart_properties[] = {
DEFINE_PROP_CHR("chardev", Exynos4210UartState, chr),
DEFINE_PROP_UINT32("channel", Exynos4210UartState, channel, 0),
DEFINE_PROP_UINT32("rx-size", Exynos4210UartState, rx.size, 16),
DEFINE_PROP_UINT32("tx-size", Exynos4210UartState, tx.size, 16),
DEFINE_PROP_END_OF_LIST(),
};
static void exynos4210_uart_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = exynos4210_uart_realize;
dc->reset = exynos4210_uart_reset;
dc->props = exynos4210_uart_properties;
dc->vmsd = &vmstate_exynos4210_uart;
}
static const TypeInfo exynos4210_uart_info = {
.name = TYPE_EXYNOS4210_UART,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(Exynos4210UartState),
.instance_init = exynos4210_uart_init,
.class_init = exynos4210_uart_class_init,
};
static void exynos4210_uart_register(void)
{
type_register_static(&exynos4210_uart_info);
}
type_init(exynos4210_uart_register)
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