| /* |
| * IMX31 UARTS |
| * |
| * Copyright (c) 2008 OKL |
| * Originally Written by Hans Jiang |
| * Copyright (c) 2011 NICTA Pty Ltd. |
| * Updated by Jean-Christophe Dubois <jcd@tribudubois.net> |
| * |
| * 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 "qemu/osdep.h" |
| #include "hw/char/imx_serial.h" |
| #include "hw/irq.h" |
| #include "hw/qdev-properties.h" |
| #include "hw/qdev-properties-system.h" |
| #include "migration/vmstate.h" |
| #include "qemu/log.h" |
| #include "qemu/module.h" |
| |
| #ifndef DEBUG_IMX_UART |
| #define DEBUG_IMX_UART 0 |
| #endif |
| |
| #define DPRINTF(fmt, args...) \ |
| do { \ |
| if (DEBUG_IMX_UART) { \ |
| fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX_SERIAL, \ |
| __func__, ##args); \ |
| } \ |
| } while (0) |
| |
| static const VMStateDescription vmstate_imx_serial = { |
| .name = TYPE_IMX_SERIAL, |
| .version_id = 2, |
| .minimum_version_id = 2, |
| .fields = (const 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_UINT32(ucr4, IMXSerialState), |
| VMSTATE_END_OF_LIST() |
| }, |
| }; |
| |
| static void imx_update(IMXSerialState *s) |
| { |
| uint32_t usr1; |
| uint32_t usr2; |
| uint32_t mask; |
| |
| /* |
| * Lucky for us TRDY and RRDY has the same offset in both USR1 and |
| * UCR1, so we can get away with something as simple as the |
| * following: |
| */ |
| usr1 = s->usr1 & s->ucr1 & (USR1_TRDY | USR1_RRDY); |
| /* |
| * Bits that we want in USR2 are not as conveniently laid out, |
| * unfortunately. |
| */ |
| mask = (s->ucr1 & UCR1_TXMPTYEN) ? USR2_TXFE : 0; |
| /* |
| * TCEN and TXDC are both bit 3 |
| * RDR and DREN are both bit 0 |
| */ |
| mask |= s->ucr4 & (UCR4_WKEN | UCR4_TCEN | UCR4_DREN); |
| |
| usr2 = s->usr2 & mask; |
| |
| qemu_set_irq(s->irq, usr1 || usr2); |
| } |
| |
| 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 = IMX_SERIAL(dev); |
| |
| imx_serial_reset(s); |
| |
| /* |
| * enable the uart on boot, so messages from the linux decompressor |
| * 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=0x%" HWADDR_PRIx ")\n", offset); |
| |
| 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_fe_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 */ |
| return s->ucr4; |
| |
| case 0x29: /* BRM Incremental */ |
| return 0x0; /* TODO */ |
| |
| default: |
| qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%" |
| HWADDR_PRIx "\n", TYPE_IMX_SERIAL, __func__, offset); |
| return 0; |
| } |
| } |
| |
| static void imx_serial_write(void *opaque, hwaddr offset, |
| uint64_t value, unsigned size) |
| { |
| IMXSerialState *s = (IMXSerialState *)opaque; |
| Chardev *chr = qemu_chr_fe_get_driver(&s->chr); |
| unsigned char ch; |
| |
| DPRINTF("write(offset=0x%" HWADDR_PRIx ", value = 0x%x) to %s\n", |
| offset, (unsigned int)value, chr ? chr->label : "NODEV"); |
| |
| switch (offset >> 2) { |
| case 0x10: /* UTXD */ |
| ch = value; |
| if (s->ucr2 & UCR2_TXEN) { |
| /* 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); |
| s->usr1 &= ~USR1_TRDY; |
| s->usr2 &= ~USR2_TXDC; |
| imx_update(s); |
| s->usr1 |= USR1_TRDY; |
| s->usr2 |= USR2_TXDC; |
| 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_fe_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 0x23: /* UCR4 */ |
| s->ucr4 = value & 0xffff; |
| imx_update(s); |
| break; |
| |
| case 0x2d: /* UTS1 */ |
| qemu_log_mask(LOG_UNIMP, "[%s]%s: Unimplemented reg 0x%" |
| HWADDR_PRIx "\n", TYPE_IMX_SERIAL, __func__, offset); |
| /* TODO */ |
| break; |
| |
| default: |
| qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%" |
| HWADDR_PRIx "\n", TYPE_IMX_SERIAL, __func__, 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; |
| if (value & URXD_BRK) { |
| s->usr2 |= USR2_BRCD; |
| } |
| imx_update(s); |
| } |
| |
| static void imx_receive(void *opaque, const uint8_t *buf, int size) |
| { |
| IMXSerialState *s = (IMXSerialState *)opaque; |
| |
| s->usr2 |= USR2_WAKE; |
| imx_put_data(opaque, *buf); |
| } |
| |
| static void imx_event(void *opaque, QEMUChrEvent event) |
| { |
| if (event == CHR_EVENT_BREAK) { |
| imx_put_data(opaque, URXD_BRK | URXD_FRMERR | URXD_ERR); |
| } |
| } |
| |
| |
| static const struct MemoryRegionOps imx_serial_ops = { |
| .read = imx_serial_read, |
| .write = imx_serial_write, |
| .endianness = DEVICE_NATIVE_ENDIAN, |
| }; |
| |
| static void imx_serial_realize(DeviceState *dev, Error **errp) |
| { |
| IMXSerialState *s = IMX_SERIAL(dev); |
| |
| DPRINTF("char dev for uart: %p\n", qemu_chr_fe_get_driver(&s->chr)); |
| |
| qemu_chr_fe_set_handlers(&s->chr, imx_can_receive, imx_receive, |
| imx_event, NULL, s, NULL, true); |
| } |
| |
| static void imx_serial_init(Object *obj) |
| { |
| SysBusDevice *sbd = SYS_BUS_DEVICE(obj); |
| IMXSerialState *s = IMX_SERIAL(obj); |
| |
| memory_region_init_io(&s->iomem, obj, &imx_serial_ops, s, |
| TYPE_IMX_SERIAL, 0x1000); |
| sysbus_init_mmio(sbd, &s->iomem); |
| sysbus_init_irq(sbd, &s->irq); |
| } |
| |
| static Property imx_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); |
| |
| dc->realize = imx_serial_realize; |
| dc->vmsd = &vmstate_imx_serial; |
| dc->reset = imx_serial_reset_at_boot; |
| set_bit(DEVICE_CATEGORY_INPUT, dc->categories); |
| dc->desc = "i.MX series UART"; |
| device_class_set_props(dc, imx_serial_properties); |
| } |
| |
| static const TypeInfo imx_serial_info = { |
| .name = TYPE_IMX_SERIAL, |
| .parent = TYPE_SYS_BUS_DEVICE, |
| .instance_size = sizeof(IMXSerialState), |
| .instance_init = imx_serial_init, |
| .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) |