| /* |
| * QEMU model of the Xilinx SPI Controller |
| * |
| * Copyright (C) 2010 Edgar E. Iglesias. |
| * Copyright (C) 2012 Peter A. G. Crosthwaite <peter.crosthwaite@petalogix.com> |
| * Copyright (C) 2012 PetaLogix |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "hw/sysbus.h" |
| #include "sysemu/sysemu.h" |
| #include "qemu/log.h" |
| #include "qemu/fifo8.h" |
| |
| #include "hw/ssi/ssi.h" |
| |
| #ifdef XILINX_SPI_ERR_DEBUG |
| #define DB_PRINT(...) do { \ |
| fprintf(stderr, ": %s: ", __func__); \ |
| fprintf(stderr, ## __VA_ARGS__); \ |
| } while (0) |
| #else |
| #define DB_PRINT(...) |
| #endif |
| |
| #define R_DGIER (0x1c / 4) |
| #define R_DGIER_IE (1 << 31) |
| |
| #define R_IPISR (0x20 / 4) |
| #define IRQ_DRR_NOT_EMPTY (1 << (31 - 23)) |
| #define IRQ_DRR_OVERRUN (1 << (31 - 26)) |
| #define IRQ_DRR_FULL (1 << (31 - 27)) |
| #define IRQ_TX_FF_HALF_EMPTY (1 << 6) |
| #define IRQ_DTR_UNDERRUN (1 << 3) |
| #define IRQ_DTR_EMPTY (1 << (31 - 29)) |
| |
| #define R_IPIER (0x28 / 4) |
| #define R_SRR (0x40 / 4) |
| #define R_SPICR (0x60 / 4) |
| #define R_SPICR_TXFF_RST (1 << 5) |
| #define R_SPICR_RXFF_RST (1 << 6) |
| #define R_SPICR_MTI (1 << 8) |
| |
| #define R_SPISR (0x64 / 4) |
| #define SR_TX_FULL (1 << 3) |
| #define SR_TX_EMPTY (1 << 2) |
| #define SR_RX_FULL (1 << 1) |
| #define SR_RX_EMPTY (1 << 0) |
| |
| #define R_SPIDTR (0x68 / 4) |
| #define R_SPIDRR (0x6C / 4) |
| #define R_SPISSR (0x70 / 4) |
| #define R_TX_FF_OCY (0x74 / 4) |
| #define R_RX_FF_OCY (0x78 / 4) |
| #define R_MAX (0x7C / 4) |
| |
| #define FIFO_CAPACITY 256 |
| |
| #define TYPE_XILINX_SPI "xlnx.xps-spi" |
| #define XILINX_SPI(obj) OBJECT_CHECK(XilinxSPI, (obj), TYPE_XILINX_SPI) |
| |
| typedef struct XilinxSPI { |
| SysBusDevice parent_obj; |
| |
| MemoryRegion mmio; |
| |
| qemu_irq irq; |
| int irqline; |
| |
| uint8_t num_cs; |
| qemu_irq *cs_lines; |
| |
| SSIBus *spi; |
| |
| Fifo8 rx_fifo; |
| Fifo8 tx_fifo; |
| |
| uint32_t regs[R_MAX]; |
| } XilinxSPI; |
| |
| static void txfifo_reset(XilinxSPI *s) |
| { |
| fifo8_reset(&s->tx_fifo); |
| |
| s->regs[R_SPISR] &= ~SR_TX_FULL; |
| s->regs[R_SPISR] |= SR_TX_EMPTY; |
| } |
| |
| static void rxfifo_reset(XilinxSPI *s) |
| { |
| fifo8_reset(&s->rx_fifo); |
| |
| s->regs[R_SPISR] |= SR_RX_EMPTY; |
| s->regs[R_SPISR] &= ~SR_RX_FULL; |
| } |
| |
| static void xlx_spi_update_cs(XilinxSPI *s) |
| { |
| int i; |
| |
| for (i = 0; i < s->num_cs; ++i) { |
| qemu_set_irq(s->cs_lines[i], !(~s->regs[R_SPISSR] & 1 << i)); |
| } |
| } |
| |
| static void xlx_spi_update_irq(XilinxSPI *s) |
| { |
| uint32_t pending; |
| |
| s->regs[R_IPISR] |= |
| (!fifo8_is_empty(&s->rx_fifo) ? IRQ_DRR_NOT_EMPTY : 0) | |
| (fifo8_is_full(&s->rx_fifo) ? IRQ_DRR_FULL : 0); |
| |
| pending = s->regs[R_IPISR] & s->regs[R_IPIER]; |
| |
| pending = pending && (s->regs[R_DGIER] & R_DGIER_IE); |
| pending = !!pending; |
| |
| /* This call lies right in the data paths so don't call the |
| irq chain unless things really changed. */ |
| if (pending != s->irqline) { |
| s->irqline = pending; |
| DB_PRINT("irq_change of state %d ISR:%x IER:%X\n", |
| pending, s->regs[R_IPISR], s->regs[R_IPIER]); |
| qemu_set_irq(s->irq, pending); |
| } |
| |
| } |
| |
| static void xlx_spi_do_reset(XilinxSPI *s) |
| { |
| memset(s->regs, 0, sizeof s->regs); |
| |
| rxfifo_reset(s); |
| txfifo_reset(s); |
| |
| s->regs[R_SPISSR] = ~0; |
| xlx_spi_update_irq(s); |
| xlx_spi_update_cs(s); |
| } |
| |
| static void xlx_spi_reset(DeviceState *d) |
| { |
| xlx_spi_do_reset(XILINX_SPI(d)); |
| } |
| |
| static inline int spi_master_enabled(XilinxSPI *s) |
| { |
| return !(s->regs[R_SPICR] & R_SPICR_MTI); |
| } |
| |
| static void spi_flush_txfifo(XilinxSPI *s) |
| { |
| uint32_t tx; |
| uint32_t rx; |
| |
| while (!fifo8_is_empty(&s->tx_fifo)) { |
| tx = (uint32_t)fifo8_pop(&s->tx_fifo); |
| DB_PRINT("data tx:%x\n", tx); |
| rx = ssi_transfer(s->spi, tx); |
| DB_PRINT("data rx:%x\n", rx); |
| if (fifo8_is_full(&s->rx_fifo)) { |
| s->regs[R_IPISR] |= IRQ_DRR_OVERRUN; |
| } else { |
| fifo8_push(&s->rx_fifo, (uint8_t)rx); |
| if (fifo8_is_full(&s->rx_fifo)) { |
| s->regs[R_SPISR] |= SR_RX_FULL; |
| s->regs[R_IPISR] |= IRQ_DRR_FULL; |
| } |
| } |
| |
| s->regs[R_SPISR] &= ~SR_RX_EMPTY; |
| s->regs[R_SPISR] &= ~SR_TX_FULL; |
| s->regs[R_SPISR] |= SR_TX_EMPTY; |
| |
| s->regs[R_IPISR] |= IRQ_DTR_EMPTY; |
| s->regs[R_IPISR] |= IRQ_DRR_NOT_EMPTY; |
| } |
| |
| } |
| |
| static uint64_t |
| spi_read(void *opaque, hwaddr addr, unsigned int size) |
| { |
| XilinxSPI *s = opaque; |
| uint32_t r = 0; |
| |
| addr >>= 2; |
| switch (addr) { |
| case R_SPIDRR: |
| if (fifo8_is_empty(&s->rx_fifo)) { |
| DB_PRINT("Read from empty FIFO!\n"); |
| return 0xdeadbeef; |
| } |
| |
| s->regs[R_SPISR] &= ~SR_RX_FULL; |
| r = fifo8_pop(&s->rx_fifo); |
| if (fifo8_is_empty(&s->rx_fifo)) { |
| s->regs[R_SPISR] |= SR_RX_EMPTY; |
| } |
| break; |
| |
| case R_SPISR: |
| r = s->regs[addr]; |
| break; |
| |
| default: |
| if (addr < ARRAY_SIZE(s->regs)) { |
| r = s->regs[addr]; |
| } |
| break; |
| |
| } |
| DB_PRINT("addr=" TARGET_FMT_plx " = %x\n", addr * 4, r); |
| xlx_spi_update_irq(s); |
| return r; |
| } |
| |
| static void |
| spi_write(void *opaque, hwaddr addr, |
| uint64_t val64, unsigned int size) |
| { |
| XilinxSPI *s = opaque; |
| uint32_t value = val64; |
| |
| DB_PRINT("addr=" TARGET_FMT_plx " = %x\n", addr, value); |
| addr >>= 2; |
| switch (addr) { |
| case R_SRR: |
| if (value != 0xa) { |
| DB_PRINT("Invalid write to SRR %x\n", value); |
| } else { |
| xlx_spi_do_reset(s); |
| } |
| break; |
| |
| case R_SPIDTR: |
| s->regs[R_SPISR] &= ~SR_TX_EMPTY; |
| fifo8_push(&s->tx_fifo, (uint8_t)value); |
| if (fifo8_is_full(&s->tx_fifo)) { |
| s->regs[R_SPISR] |= SR_TX_FULL; |
| } |
| if (!spi_master_enabled(s)) { |
| goto done; |
| } else { |
| DB_PRINT("DTR and master enabled\n"); |
| } |
| spi_flush_txfifo(s); |
| break; |
| |
| case R_SPISR: |
| DB_PRINT("Invalid write to SPISR %x\n", value); |
| break; |
| |
| case R_IPISR: |
| /* Toggle the bits. */ |
| s->regs[addr] ^= value; |
| break; |
| |
| /* Slave Select Register. */ |
| case R_SPISSR: |
| s->regs[addr] = value; |
| xlx_spi_update_cs(s); |
| break; |
| |
| case R_SPICR: |
| /* FIXME: reset irq and sr state to empty queues. */ |
| if (value & R_SPICR_RXFF_RST) { |
| rxfifo_reset(s); |
| } |
| |
| if (value & R_SPICR_TXFF_RST) { |
| txfifo_reset(s); |
| } |
| value &= ~(R_SPICR_RXFF_RST | R_SPICR_TXFF_RST); |
| s->regs[addr] = value; |
| |
| if (!(value & R_SPICR_MTI)) { |
| spi_flush_txfifo(s); |
| } |
| break; |
| |
| default: |
| if (addr < ARRAY_SIZE(s->regs)) { |
| s->regs[addr] = value; |
| } |
| break; |
| } |
| |
| done: |
| xlx_spi_update_irq(s); |
| } |
| |
| static const MemoryRegionOps spi_ops = { |
| .read = spi_read, |
| .write = spi_write, |
| .endianness = DEVICE_NATIVE_ENDIAN, |
| .valid = { |
| .min_access_size = 4, |
| .max_access_size = 4 |
| } |
| }; |
| |
| static void xilinx_spi_realize(DeviceState *dev, Error **errp) |
| { |
| SysBusDevice *sbd = SYS_BUS_DEVICE(dev); |
| XilinxSPI *s = XILINX_SPI(dev); |
| int i; |
| |
| DB_PRINT("\n"); |
| |
| s->spi = ssi_create_bus(dev, "spi"); |
| |
| sysbus_init_irq(sbd, &s->irq); |
| s->cs_lines = g_new0(qemu_irq, s->num_cs); |
| ssi_auto_connect_slaves(dev, s->cs_lines, s->spi); |
| for (i = 0; i < s->num_cs; ++i) { |
| sysbus_init_irq(sbd, &s->cs_lines[i]); |
| } |
| |
| memory_region_init_io(&s->mmio, OBJECT(s), &spi_ops, s, |
| "xilinx-spi", R_MAX * 4); |
| sysbus_init_mmio(sbd, &s->mmio); |
| |
| s->irqline = -1; |
| |
| fifo8_create(&s->tx_fifo, FIFO_CAPACITY); |
| fifo8_create(&s->rx_fifo, FIFO_CAPACITY); |
| } |
| |
| static const VMStateDescription vmstate_xilinx_spi = { |
| .name = "xilinx_spi", |
| .version_id = 1, |
| .minimum_version_id = 1, |
| .fields = (VMStateField[]) { |
| VMSTATE_FIFO8(tx_fifo, XilinxSPI), |
| VMSTATE_FIFO8(rx_fifo, XilinxSPI), |
| VMSTATE_UINT32_ARRAY(regs, XilinxSPI, R_MAX), |
| VMSTATE_END_OF_LIST() |
| } |
| }; |
| |
| static Property xilinx_spi_properties[] = { |
| DEFINE_PROP_UINT8("num-ss-bits", XilinxSPI, num_cs, 1), |
| DEFINE_PROP_END_OF_LIST(), |
| }; |
| |
| static void xilinx_spi_class_init(ObjectClass *klass, void *data) |
| { |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| |
| dc->realize = xilinx_spi_realize; |
| dc->reset = xlx_spi_reset; |
| dc->props = xilinx_spi_properties; |
| dc->vmsd = &vmstate_xilinx_spi; |
| } |
| |
| static const TypeInfo xilinx_spi_info = { |
| .name = TYPE_XILINX_SPI, |
| .parent = TYPE_SYS_BUS_DEVICE, |
| .instance_size = sizeof(XilinxSPI), |
| .class_init = xilinx_spi_class_init, |
| }; |
| |
| static void xilinx_spi_register_types(void) |
| { |
| type_register_static(&xilinx_spi_info); |
| } |
| |
| type_init(xilinx_spi_register_types) |