|  | /* | 
|  | * IMX31 UARTS | 
|  | * | 
|  | * Copyright (c) 2008 OKL | 
|  | * Originally Written by Hans Jiang | 
|  | * Copyright (c) 2011 NICTA Pty Ltd. | 
|  | * | 
|  | * This work is licensed under the terms of the GNU GPL, version 2 or later. | 
|  | * See the COPYING file in the top-level directory. | 
|  | * | 
|  | * This is a `bare-bones' implementation of the IMX series serial ports. | 
|  | * TODO: | 
|  | *  -- implement FIFOs.  The real hardware has 32 word transmit | 
|  | *                       and receive FIFOs; we currently use a 1-char buffer | 
|  | *  -- implement DMA | 
|  | *  -- implement BAUD-rate and modem lines, for when the backend | 
|  | *     is a real serial device. | 
|  | */ | 
|  |  | 
|  | #include "hw.h" | 
|  | #include "sysbus.h" | 
|  | #include "sysemu.h" | 
|  | #include "qemu-char.h" | 
|  | #include "imx.h" | 
|  |  | 
|  | //#define DEBUG_SERIAL 1 | 
|  | #ifdef DEBUG_SERIAL | 
|  | #define DPRINTF(fmt, args...) \ | 
|  | do { printf("imx_serial: " fmt , ##args); } while (0) | 
|  | #else | 
|  | #define DPRINTF(fmt, args...) do {} while (0) | 
|  | #endif | 
|  |  | 
|  | /* | 
|  | * Define to 1 for messages about attempts to | 
|  | * access unimplemented registers or similar. | 
|  | */ | 
|  | //#define DEBUG_IMPLEMENTATION 1 | 
|  | #ifdef DEBUG_IMPLEMENTATION | 
|  | #  define IPRINTF(fmt, args...) \ | 
|  | do  { fprintf(stderr, "imx_serial: " fmt, ##args); } while (0) | 
|  | #else | 
|  | #  define IPRINTF(fmt, args...) do {} while (0) | 
|  | #endif | 
|  |  | 
|  | typedef struct { | 
|  | SysBusDevice busdev; | 
|  | MemoryRegion iomem; | 
|  | int32_t readbuff; | 
|  |  | 
|  | uint32_t usr1; | 
|  | uint32_t usr2; | 
|  | uint32_t ucr1; | 
|  | uint32_t ucr2; | 
|  | uint32_t uts1; | 
|  |  | 
|  | /* | 
|  | * The registers below are implemented just so that the | 
|  | * guest OS sees what it has written | 
|  | */ | 
|  | uint32_t onems; | 
|  | uint32_t ufcr; | 
|  | uint32_t ubmr; | 
|  | uint32_t ubrc; | 
|  | uint32_t ucr3; | 
|  |  | 
|  | qemu_irq irq; | 
|  | CharDriverState *chr; | 
|  | } IMXSerialState; | 
|  |  | 
|  | static const VMStateDescription vmstate_imx_serial = { | 
|  | .name = "imx-serial", | 
|  | .version_id = 1, | 
|  | .minimum_version_id = 1, | 
|  | .minimum_version_id_old = 1, | 
|  | .fields = (VMStateField[]) { | 
|  | VMSTATE_INT32(readbuff, IMXSerialState), | 
|  | VMSTATE_UINT32(usr1, IMXSerialState), | 
|  | VMSTATE_UINT32(usr2, IMXSerialState), | 
|  | VMSTATE_UINT32(ucr1, IMXSerialState), | 
|  | VMSTATE_UINT32(uts1, IMXSerialState), | 
|  | VMSTATE_UINT32(onems, IMXSerialState), | 
|  | VMSTATE_UINT32(ufcr, IMXSerialState), | 
|  | VMSTATE_UINT32(ubmr, IMXSerialState), | 
|  | VMSTATE_UINT32(ubrc, IMXSerialState), | 
|  | VMSTATE_UINT32(ucr3, IMXSerialState), | 
|  | VMSTATE_END_OF_LIST() | 
|  | }, | 
|  | }; | 
|  |  | 
|  |  | 
|  | #define URXD_CHARRDY    (1<<15)   /* character read is valid */ | 
|  | #define URXD_ERR        (1<<14)   /* Character has error */ | 
|  | #define URXD_BRK        (1<<11)   /* Break received */ | 
|  |  | 
|  | #define USR1_PARTYER    (1<<15)   /* Parity Error */ | 
|  | #define USR1_RTSS       (1<<14)   /* RTS pin status */ | 
|  | #define USR1_TRDY       (1<<13)   /* Tx ready */ | 
|  | #define USR1_RTSD       (1<<12)   /* RTS delta: pin changed state */ | 
|  | #define USR1_ESCF       (1<<11)   /* Escape sequence interrupt */ | 
|  | #define USR1_FRAMERR    (1<<10)   /* Framing error  */ | 
|  | #define USR1_RRDY       (1<<9)    /* receiver ready */ | 
|  | #define USR1_AGTIM      (1<<8)    /* Aging timer interrupt */ | 
|  | #define USR1_DTRD       (1<<7)    /* DTR changed */ | 
|  | #define USR1_RXDS       (1<<6)    /* Receiver is idle */ | 
|  | #define USR1_AIRINT     (1<<5)    /* Aysnch IR interrupt */ | 
|  | #define USR1_AWAKE      (1<<4)    /* Falling edge detected on RXd pin */ | 
|  |  | 
|  | #define USR2_ADET       (1<<15)   /* Autobaud complete */ | 
|  | #define USR2_TXFE       (1<<14)   /* Transmit FIFO empty */ | 
|  | #define USR2_DTRF       (1<<13)   /* DTR/DSR transition */ | 
|  | #define USR2_IDLE       (1<<12)   /* UART has been idle for too long */ | 
|  | #define USR2_ACST       (1<<11)   /* Autobaud counter stopped */ | 
|  | #define USR2_RIDELT     (1<<10)   /* Ring Indicator delta */ | 
|  | #define USR2_RIIN       (1<<9)    /* Ring Indicator Input */ | 
|  | #define USR2_IRINT      (1<<8)    /* Serial Infrared Interrupt */ | 
|  | #define USR2_WAKE       (1<<7)    /* Start bit detected */ | 
|  | #define USR2_DCDDELT    (1<<6)    /* Data Carrier Detect delta */ | 
|  | #define USR2_DCDIN      (1<<5)    /* Data Carrier Detect Input */ | 
|  | #define USR2_RTSF       (1<<4)    /* RTS transition */ | 
|  | #define USR2_TXDC       (1<<3)    /* Transmission complete */ | 
|  | #define USR2_BRCD       (1<<2)    /* Break condition detected */ | 
|  | #define USR2_ORE        (1<<1)    /* Overrun error */ | 
|  | #define USR2_RDR        (1<<0)    /* Receive data ready */ | 
|  |  | 
|  | #define UCR1_TRDYEN     (1<<13)   /* Tx Ready Interrupt Enable */ | 
|  | #define UCR1_RRDYEN     (1<<9)    /* Rx Ready Interrupt Enable */ | 
|  | #define UCR1_TXMPTYEN   (1<<6)    /* Tx Empty Interrupt Enable */ | 
|  | #define UCR1_UARTEN     (1<<0)    /* UART Enable */ | 
|  |  | 
|  | #define UCR2_TXEN       (1<<2)    /* Transmitter enable */ | 
|  | #define UCR2_RXEN       (1<<1)    /* Receiver enable */ | 
|  | #define UCR2_SRST       (1<<0)    /* Reset complete */ | 
|  |  | 
|  | #define UTS1_TXEMPTY    (1<<6) | 
|  | #define UTS1_RXEMPTY    (1<<5) | 
|  | #define UTS1_TXFULL     (1<<4) | 
|  | #define UTS1_RXFULL     (1<<3) | 
|  |  | 
|  | static void imx_update(IMXSerialState *s) | 
|  | { | 
|  | uint32_t flags; | 
|  |  | 
|  | flags = (s->usr1 & s->ucr1) & (USR1_TRDY|USR1_RRDY); | 
|  | if (!(s->ucr1 & UCR1_TXMPTYEN)) { | 
|  | flags &= ~USR1_TRDY; | 
|  | } | 
|  |  | 
|  | qemu_set_irq(s->irq, !!flags); | 
|  | } | 
|  |  | 
|  | static void imx_serial_reset(IMXSerialState *s) | 
|  | { | 
|  |  | 
|  | s->usr1 = USR1_TRDY | USR1_RXDS; | 
|  | /* | 
|  | * Fake attachment of a terminal: assert RTS. | 
|  | */ | 
|  | s->usr1 |= USR1_RTSS; | 
|  | s->usr2 = USR2_TXFE | USR2_TXDC | USR2_DCDIN; | 
|  | s->uts1 = UTS1_RXEMPTY | UTS1_TXEMPTY; | 
|  | s->ucr1 = 0; | 
|  | s->ucr2 = UCR2_SRST; | 
|  | s->ucr3 = 0x700; | 
|  | s->ubmr = 0; | 
|  | s->ubrc = 4; | 
|  | s->readbuff = URXD_ERR; | 
|  | } | 
|  |  | 
|  | static void imx_serial_reset_at_boot(DeviceState *dev) | 
|  | { | 
|  | IMXSerialState *s = container_of(dev, IMXSerialState, busdev.qdev); | 
|  |  | 
|  | imx_serial_reset(s); | 
|  |  | 
|  | /* | 
|  | * enable the uart on boot, so messages from the linux decompresser | 
|  | * are visible.  On real hardware this is done by the boot rom | 
|  | * before anything else is loaded. | 
|  | */ | 
|  | s->ucr1 = UCR1_UARTEN; | 
|  | s->ucr2 = UCR2_TXEN; | 
|  |  | 
|  | } | 
|  |  | 
|  | static uint64_t imx_serial_read(void *opaque, hwaddr offset, | 
|  | unsigned size) | 
|  | { | 
|  | IMXSerialState *s = (IMXSerialState *)opaque; | 
|  | uint32_t c; | 
|  |  | 
|  | DPRINTF("read(offset=%x)\n", offset >> 2); | 
|  | switch (offset >> 2) { | 
|  | case 0x0: /* URXD */ | 
|  | c = s->readbuff; | 
|  | if (!(s->uts1 & UTS1_RXEMPTY)) { | 
|  | /* Character is valid */ | 
|  | c |= URXD_CHARRDY; | 
|  | s->usr1 &= ~USR1_RRDY; | 
|  | s->usr2 &= ~USR2_RDR; | 
|  | s->uts1 |= UTS1_RXEMPTY; | 
|  | imx_update(s); | 
|  | qemu_chr_accept_input(s->chr); | 
|  | } | 
|  | return c; | 
|  |  | 
|  | case 0x20: /* UCR1 */ | 
|  | return s->ucr1; | 
|  |  | 
|  | case 0x21: /* UCR2 */ | 
|  | return s->ucr2; | 
|  |  | 
|  | case 0x25: /* USR1 */ | 
|  | return s->usr1; | 
|  |  | 
|  | case 0x26: /* USR2 */ | 
|  | return s->usr2; | 
|  |  | 
|  | case 0x2A: /* BRM Modulator */ | 
|  | return s->ubmr; | 
|  |  | 
|  | case 0x2B: /* Baud Rate Count */ | 
|  | return s->ubrc; | 
|  |  | 
|  | case 0x2d: /* Test register */ | 
|  | return s->uts1; | 
|  |  | 
|  | case 0x24: /* UFCR */ | 
|  | return s->ufcr; | 
|  |  | 
|  | case 0x2c: | 
|  | return s->onems; | 
|  |  | 
|  | case 0x22: /* UCR3 */ | 
|  | return s->ucr3; | 
|  |  | 
|  | case 0x23: /* UCR4 */ | 
|  | case 0x29: /* BRM Incremental */ | 
|  | return 0x0; /* TODO */ | 
|  |  | 
|  | default: | 
|  | IPRINTF("imx_serial_read: bad offset: 0x%x\n", (int)offset); | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | static void imx_serial_write(void *opaque, hwaddr offset, | 
|  | uint64_t value, unsigned size) | 
|  | { | 
|  | IMXSerialState *s = (IMXSerialState *)opaque; | 
|  | unsigned char ch; | 
|  |  | 
|  | DPRINTF("write(offset=%x, value = %x) to %s\n", | 
|  | offset >> 2, | 
|  | (unsigned int)value, s->chr ? s->chr->label : "NODEV"); | 
|  |  | 
|  | switch (offset >> 2) { | 
|  | case 0x10: /* UTXD */ | 
|  | ch = value; | 
|  | if (s->ucr2 & UCR2_TXEN) { | 
|  | if (s->chr) { | 
|  | qemu_chr_fe_write(s->chr, &ch, 1); | 
|  | } | 
|  | s->usr1 &= ~USR1_TRDY; | 
|  | imx_update(s); | 
|  | s->usr1 |= USR1_TRDY; | 
|  | imx_update(s); | 
|  | } | 
|  | break; | 
|  |  | 
|  | case 0x20: /* UCR1 */ | 
|  | s->ucr1 = value & 0xffff; | 
|  | DPRINTF("write(ucr1=%x)\n", (unsigned int)value); | 
|  | imx_update(s); | 
|  | break; | 
|  |  | 
|  | case 0x21: /* UCR2 */ | 
|  | /* | 
|  | * Only a few bits in control register 2 are implemented as yet. | 
|  | * If it's intended to use a real serial device as a back-end, this | 
|  | * register will have to be implemented more fully. | 
|  | */ | 
|  | if (!(value & UCR2_SRST)) { | 
|  | imx_serial_reset(s); | 
|  | imx_update(s); | 
|  | value |= UCR2_SRST; | 
|  | } | 
|  | if (value & UCR2_RXEN) { | 
|  | if (!(s->ucr2 & UCR2_RXEN)) { | 
|  | qemu_chr_accept_input(s->chr); | 
|  | } | 
|  | } | 
|  | s->ucr2 = value & 0xffff; | 
|  | break; | 
|  |  | 
|  | case 0x25: /* USR1 */ | 
|  | value &= USR1_AWAKE | USR1_AIRINT | USR1_DTRD | USR1_AGTIM | | 
|  | USR1_FRAMERR | USR1_ESCF | USR1_RTSD | USR1_PARTYER; | 
|  | s->usr1 &= ~value; | 
|  | break; | 
|  |  | 
|  | case 0x26: /* USR2 */ | 
|  | /* | 
|  | * Writing 1 to some bits clears them; all other | 
|  | * values are ignored | 
|  | */ | 
|  | value &= USR2_ADET | USR2_DTRF | USR2_IDLE | USR2_ACST | | 
|  | USR2_RIDELT | USR2_IRINT | USR2_WAKE | | 
|  | USR2_DCDDELT | USR2_RTSF | USR2_BRCD | USR2_ORE; | 
|  | s->usr2 &= ~value; | 
|  | break; | 
|  |  | 
|  | /* | 
|  | * Linux expects to see what it writes to these registers | 
|  | * We don't currently alter the baud rate | 
|  | */ | 
|  | case 0x29: /* UBIR */ | 
|  | s->ubrc = value & 0xffff; | 
|  | break; | 
|  |  | 
|  | case 0x2a: /* UBMR */ | 
|  | s->ubmr = value & 0xffff; | 
|  | break; | 
|  |  | 
|  | case 0x2c: /* One ms reg */ | 
|  | s->onems = value & 0xffff; | 
|  | break; | 
|  |  | 
|  | case 0x24: /* FIFO control register */ | 
|  | s->ufcr = value & 0xffff; | 
|  | break; | 
|  |  | 
|  | case 0x22: /* UCR3 */ | 
|  | s->ucr3 = value & 0xffff; | 
|  | break; | 
|  |  | 
|  | case 0x2d: /* UTS1 */ | 
|  | case 0x23: /* UCR4 */ | 
|  | IPRINTF("Unimplemented Register %x written to\n", offset >> 2); | 
|  | /* TODO */ | 
|  | break; | 
|  |  | 
|  | default: | 
|  | IPRINTF("imx_serial_write: Bad offset 0x%x\n", (int)offset); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int imx_can_receive(void *opaque) | 
|  | { | 
|  | IMXSerialState *s = (IMXSerialState *)opaque; | 
|  | return !(s->usr1 & USR1_RRDY); | 
|  | } | 
|  |  | 
|  | static void imx_put_data(void *opaque, uint32_t value) | 
|  | { | 
|  | IMXSerialState *s = (IMXSerialState *)opaque; | 
|  | DPRINTF("received char\n"); | 
|  | s->usr1 |= USR1_RRDY; | 
|  | s->usr2 |= USR2_RDR; | 
|  | s->uts1 &= ~UTS1_RXEMPTY; | 
|  | s->readbuff = value; | 
|  | imx_update(s); | 
|  | } | 
|  |  | 
|  | static void imx_receive(void *opaque, const uint8_t *buf, int size) | 
|  | { | 
|  | imx_put_data(opaque, *buf); | 
|  | } | 
|  |  | 
|  | static void imx_event(void *opaque, int event) | 
|  | { | 
|  | if (event == CHR_EVENT_BREAK) { | 
|  | imx_put_data(opaque, URXD_BRK); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | static const struct MemoryRegionOps imx_serial_ops = { | 
|  | .read = imx_serial_read, | 
|  | .write = imx_serial_write, | 
|  | .endianness = DEVICE_NATIVE_ENDIAN, | 
|  | }; | 
|  |  | 
|  | static int imx_serial_init(SysBusDevice *dev) | 
|  | { | 
|  | IMXSerialState *s = FROM_SYSBUS(IMXSerialState, dev); | 
|  |  | 
|  |  | 
|  | memory_region_init_io(&s->iomem, &imx_serial_ops, s, "imx-serial", 0x1000); | 
|  | sysbus_init_mmio(dev, &s->iomem); | 
|  | sysbus_init_irq(dev, &s->irq); | 
|  |  | 
|  | if (s->chr) { | 
|  | qemu_chr_add_handlers(s->chr, imx_can_receive, imx_receive, | 
|  | imx_event, s); | 
|  | } else { | 
|  | DPRINTF("No char dev for uart at 0x%lx\n", | 
|  | (unsigned long)s->iomem.ram_addr); | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void imx_serial_create(int uart, const hwaddr addr, qemu_irq irq) | 
|  | { | 
|  | DeviceState *dev; | 
|  | SysBusDevice *bus; | 
|  | CharDriverState *chr; | 
|  | const char chr_name[] = "serial"; | 
|  | char label[ARRAY_SIZE(chr_name) + 1]; | 
|  |  | 
|  | dev = qdev_create(NULL, "imx-serial"); | 
|  |  | 
|  | if (uart >= MAX_SERIAL_PORTS) { | 
|  | hw_error("Cannot assign uart %d: QEMU supports only %d ports\n", | 
|  | uart, MAX_SERIAL_PORTS); | 
|  | } | 
|  | chr = serial_hds[uart]; | 
|  | if (!chr) { | 
|  | snprintf(label, ARRAY_SIZE(label), "%s%d", chr_name, uart); | 
|  | chr = qemu_chr_new(label, "null", NULL); | 
|  | if (!(chr)) { | 
|  | hw_error("Can't assign serial port to imx-uart%d.\n", uart); | 
|  | } | 
|  | } | 
|  |  | 
|  | qdev_prop_set_chr(dev, "chardev", chr); | 
|  | bus = sysbus_from_qdev(dev); | 
|  | qdev_init_nofail(dev); | 
|  | if (addr != (hwaddr)-1) { | 
|  | sysbus_mmio_map(bus, 0, addr); | 
|  | } | 
|  | sysbus_connect_irq(bus, 0, irq); | 
|  |  | 
|  | } | 
|  |  | 
|  |  | 
|  | static Property imx32_serial_properties[] = { | 
|  | DEFINE_PROP_CHR("chardev", IMXSerialState, chr), | 
|  | DEFINE_PROP_END_OF_LIST(), | 
|  | }; | 
|  |  | 
|  | static void imx_serial_class_init(ObjectClass *klass, void *data) | 
|  | { | 
|  | DeviceClass *dc = DEVICE_CLASS(klass); | 
|  | SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass); | 
|  |  | 
|  | k->init = imx_serial_init; | 
|  | dc->vmsd = &vmstate_imx_serial; | 
|  | dc->reset = imx_serial_reset_at_boot; | 
|  | dc->desc = "i.MX series UART"; | 
|  | dc->props = imx32_serial_properties; | 
|  | } | 
|  |  | 
|  | static TypeInfo imx_serial_info = { | 
|  | .name = "imx-serial", | 
|  | .parent = TYPE_SYS_BUS_DEVICE, | 
|  | .instance_size = sizeof(IMXSerialState), | 
|  | .class_init = imx_serial_class_init, | 
|  | }; | 
|  |  | 
|  | static void imx_serial_register_types(void) | 
|  | { | 
|  | type_register_static(&imx_serial_info); | 
|  | } | 
|  |  | 
|  | type_init(imx_serial_register_types) |