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Diffstat (limited to 'hw/misc/mps2-fpgaio.c')
| -rw-r--r-- | hw/misc/mps2-fpgaio.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/hw/misc/mps2-fpgaio.c b/hw/misc/mps2-fpgaio.c new file mode 100644 index 0000000000..7394a057d8 --- /dev/null +++ b/hw/misc/mps2-fpgaio.c @@ -0,0 +1,176 @@ +/* + * ARM MPS2 AN505 FPGAIO emulation + * + * Copyright (c) 2018 Linaro Limited + * Written by Peter Maydell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 or + * (at your option) any later version. + */ + +/* This is a model of the "FPGA system control and I/O" block found + * in the AN505 FPGA image for the MPS2 devboard. + * It is documented in AN505: + * http://infocenter.arm.com/help/topic/com.arm.doc.dai0505b/index.html + */ + +#include "qemu/osdep.h" +#include "qemu/log.h" +#include "qapi/error.h" +#include "trace.h" +#include "hw/sysbus.h" +#include "hw/registerfields.h" +#include "hw/misc/mps2-fpgaio.h" + +REG32(LED0, 0) +REG32(BUTTON, 8) +REG32(CLK1HZ, 0x10) +REG32(CLK100HZ, 0x14) +REG32(COUNTER, 0x18) +REG32(PRESCALE, 0x1c) +REG32(PSCNTR, 0x20) +REG32(MISC, 0x4c) + +static uint64_t mps2_fpgaio_read(void *opaque, hwaddr offset, unsigned size) +{ + MPS2FPGAIO *s = MPS2_FPGAIO(opaque); + uint64_t r; + + switch (offset) { + case A_LED0: + r = s->led0; + break; + case A_BUTTON: + /* User-pressable board buttons. We don't model that, so just return + * zeroes. + */ + r = 0; + break; + case A_PRESCALE: + r = s->prescale; + break; + case A_MISC: + r = s->misc; + break; + case A_CLK1HZ: + case A_CLK100HZ: + case A_COUNTER: + case A_PSCNTR: + /* These are all upcounters of various frequencies. */ + qemu_log_mask(LOG_UNIMP, "MPS2 FPGAIO: counters unimplemented\n"); + r = 0; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "MPS2 FPGAIO read: bad offset %x\n", (int) offset); + r = 0; + break; + } + + trace_mps2_fpgaio_read(offset, r, size); + return r; +} + +static void mps2_fpgaio_write(void *opaque, hwaddr offset, uint64_t value, + unsigned size) +{ + MPS2FPGAIO *s = MPS2_FPGAIO(opaque); + + trace_mps2_fpgaio_write(offset, value, size); + + switch (offset) { + case A_LED0: + /* LED bits [1:0] control board LEDs. We don't currently have + * a mechanism for displaying this graphically, so use a trace event. + */ + trace_mps2_fpgaio_leds(value & 0x02 ? '*' : '.', + value & 0x01 ? '*' : '.'); + s->led0 = value & 0x3; + break; + case A_PRESCALE: + s->prescale = value; + break; + case A_MISC: + /* These are control bits for some of the other devices on the + * board (SPI, CLCD, etc). We don't implement that yet, so just + * make the bits read as written. + */ + qemu_log_mask(LOG_UNIMP, + "MPS2 FPGAIO: MISC control bits unimplemented\n"); + s->misc = value; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "MPS2 FPGAIO write: bad offset 0x%x\n", (int) offset); + break; + } +} + +static const MemoryRegionOps mps2_fpgaio_ops = { + .read = mps2_fpgaio_read, + .write = mps2_fpgaio_write, + .endianness = DEVICE_LITTLE_ENDIAN, +}; + +static void mps2_fpgaio_reset(DeviceState *dev) +{ + MPS2FPGAIO *s = MPS2_FPGAIO(dev); + + trace_mps2_fpgaio_reset(); + s->led0 = 0; + s->prescale = 0; + s->misc = 0; +} + +static void mps2_fpgaio_init(Object *obj) +{ + SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + MPS2FPGAIO *s = MPS2_FPGAIO(obj); + + memory_region_init_io(&s->iomem, obj, &mps2_fpgaio_ops, s, + "mps2-fpgaio", 0x1000); + sysbus_init_mmio(sbd, &s->iomem); +} + +static const VMStateDescription mps2_fpgaio_vmstate = { + .name = "mps2-fpgaio", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32(led0, MPS2FPGAIO), + VMSTATE_UINT32(prescale, MPS2FPGAIO), + VMSTATE_UINT32(misc, MPS2FPGAIO), + VMSTATE_END_OF_LIST() + } +}; + +static Property mps2_fpgaio_properties[] = { + /* Frequency of the prescale counter */ + DEFINE_PROP_UINT32("prescale-clk", MPS2FPGAIO, prescale_clk, 20000000), + DEFINE_PROP_END_OF_LIST(), +}; + +static void mps2_fpgaio_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->vmsd = &mps2_fpgaio_vmstate; + dc->reset = mps2_fpgaio_reset; + dc->props = mps2_fpgaio_properties; +} + +static const TypeInfo mps2_fpgaio_info = { + .name = TYPE_MPS2_FPGAIO, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(MPS2FPGAIO), + .instance_init = mps2_fpgaio_init, + .class_init = mps2_fpgaio_class_init, +}; + +static void mps2_fpgaio_register_types(void) +{ + type_register_static(&mps2_fpgaio_info); +} + +type_init(mps2_fpgaio_register_types); |