/* * Raspberry Pi emulation (c) 2012 Gregory Estrade * This code is licensed under the GNU GPLv2 and later. */ #include "qemu/osdep.h" #include "qapi/error.h" #include "hw/dma/bcm2835_dma.h" #include "qemu/log.h" /* DMA CS Control and Status bits */ #define BCM2708_DMA_ACTIVE (1 << 0) #define BCM2708_DMA_END (1 << 1) /* GE */ #define BCM2708_DMA_INT (1 << 2) #define BCM2708_DMA_ISPAUSED (1 << 4) /* Pause requested or not active */ #define BCM2708_DMA_ISHELD (1 << 5) /* Is held by DREQ flow control */ #define BCM2708_DMA_ERR (1 << 8) #define BCM2708_DMA_ABORT (1 << 30) /* stop current CB, go to next, WO */ #define BCM2708_DMA_RESET (1 << 31) /* WO, self clearing */ /* DMA control block "info" field bits */ #define BCM2708_DMA_INT_EN (1 << 0) #define BCM2708_DMA_TDMODE (1 << 1) #define BCM2708_DMA_WAIT_RESP (1 << 3) #define BCM2708_DMA_D_INC (1 << 4) #define BCM2708_DMA_D_WIDTH (1 << 5) #define BCM2708_DMA_D_DREQ (1 << 6) #define BCM2708_DMA_D_IGNORE (1 << 7) #define BCM2708_DMA_S_INC (1 << 8) #define BCM2708_DMA_S_WIDTH (1 << 9) #define BCM2708_DMA_S_DREQ (1 << 10) #define BCM2708_DMA_S_IGNORE (1 << 11) /* Register offsets */ #define BCM2708_DMA_CS 0x00 /* Control and Status */ #define BCM2708_DMA_ADDR 0x04 /* Control block address */ /* the current control block appears in the following registers - read only */ #define BCM2708_DMA_INFO 0x08 #define BCM2708_DMA_SOURCE_AD 0x0c #define BCM2708_DMA_DEST_AD 0x10 #define BCM2708_DMA_TXFR_LEN 0x14 #define BCM2708_DMA_STRIDE 0x18 #define BCM2708_DMA_NEXTCB 0x1C #define BCM2708_DMA_DEBUG 0x20 #define BCM2708_DMA_INT_STATUS 0xfe0 /* Interrupt status of each channel */ #define BCM2708_DMA_ENABLE 0xff0 /* Global enable bits for each channel */ #define BCM2708_DMA_CS_RW_MASK 0x30ff0001 /* All RW bits in DMA_CS */ static void bcm2835_dma_update(BCM2835DMAState *s, unsigned c) { BCM2835DMAChan *ch = &s->chan[c]; uint32_t data, xlen, ylen; int16_t dst_stride, src_stride; if (!(s->enable & (1 << c))) { return; } while ((s->enable & (1 << c)) && (ch->conblk_ad != 0)) { /* CB fetch */ ch->ti = ldl_le_phys(&s->dma_as, ch->conblk_ad); ch->source_ad = ldl_le_phys(&s->dma_as, ch->conblk_ad + 4); ch->dest_ad = ldl_le_phys(&s->dma_as, ch->conblk_ad + 8); ch->txfr_len = ldl_le_phys(&s->dma_as, ch->conblk_ad + 12); ch->stride = ldl_le_phys(&s->dma_as, ch->conblk_ad + 16); ch->nextconbk = ldl_le_phys(&s->dma_as, ch->conblk_ad + 20); if (ch->ti & BCM2708_DMA_TDMODE) { /* 2D transfer mode */ ylen = (ch->txfr_len >> 16) & 0x3fff; xlen = ch->txfr_len & 0xffff; dst_stride = ch->stride >> 16; src_stride = ch->stride & 0xffff; } else { ylen = 1; xlen = ch->txfr_len; dst_stride = 0; src_stride = 0; } while (ylen != 0) { /* Normal transfer mode */ while (xlen != 0) { if (ch->ti & BCM2708_DMA_S_IGNORE) { /* Ignore reads */ data = 0; } else { data = ldl_le_phys(&s->dma_as, ch->source_ad); } if (ch->ti & BCM2708_DMA_S_INC) { ch->source_ad += 4; } if (ch->ti & BCM2708_DMA_D_IGNORE) { /* Ignore writes */ } else { stl_le_phys(&s->dma_as, ch->dest_ad, data); } if (ch->ti & BCM2708_DMA_D_INC) { ch->dest_ad += 4; } /* update remaining transfer length */ xlen -= 4; if (ch->ti & BCM2708_DMA_TDMODE) { ch->txfr_len = (ylen << 16) | xlen; } else { ch->txfr_len = xlen; } } if (--ylen != 0) { ch->source_ad += src_stride; ch->dest_ad += dst_stride; } } ch->cs |= BCM2708_DMA_END; if (ch->ti & BCM2708_DMA_INT_EN) { ch->cs |= BCM2708_DMA_INT; s->int_status |= (1 << c); qemu_set_irq(ch->irq, 1); } /* Process next CB */ ch->conblk_ad = ch->nextconbk; } ch->cs &= ~BCM2708_DMA_ACTIVE; ch->cs |= BCM2708_DMA_ISPAUSED; } static void bcm2835_dma_chan_reset(BCM2835DMAChan *ch) { ch->cs = 0; ch->conblk_ad = 0; } static uint64_t bcm2835_dma_read(BCM2835DMAState *s, hwaddr offset, unsigned size, unsigned c) { BCM2835DMAChan *ch; uint32_t res = 0; assert(size == 4); assert(c < BCM2835_DMA_NCHANS); ch = &s->chan[c]; switch (offset) { case BCM2708_DMA_CS: res = ch->cs; break; case BCM2708_DMA_ADDR: res = ch->conblk_ad; break; case BCM2708_DMA_INFO: res = ch->ti; break; case BCM2708_DMA_SOURCE_AD: res = ch->source_ad; break; case BCM2708_DMA_DEST_AD: res = ch->dest_ad; break; case BCM2708_DMA_TXFR_LEN: res = ch->txfr_len; break; case BCM2708_DMA_STRIDE: res = ch->stride; break; case BCM2708_DMA_NEXTCB: res = ch->nextconbk; break; case BCM2708_DMA_DEBUG: res = ch->debug; break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", __func__, offset); break; } return res; } static void bcm2835_dma_write(BCM2835DMAState *s, hwaddr offset, uint64_t value, unsigned size, unsigned c) { BCM2835DMAChan *ch; uint32_t oldcs; assert(size == 4); assert(c < BCM2835_DMA_NCHANS); ch = &s->chan[c]; switch (offset) { case BCM2708_DMA_CS: oldcs = ch->cs; if (value & BCM2708_DMA_RESET) { bcm2835_dma_chan_reset(ch); } if (value & BCM2708_DMA_ABORT) { /* abort is a no-op, since we always run to completion */ } if (value & BCM2708_DMA_END) { ch->cs &= ~BCM2708_DMA_END; } if (value & BCM2708_DMA_INT) { ch->cs &= ~BCM2708_DMA_INT; s->int_status &= ~(1 << c); qemu_set_irq(ch->irq, 0); } ch->cs &= ~BCM2708_DMA_CS_RW_MASK; ch->cs |= (value & BCM2708_DMA_CS_RW_MASK); if (!(oldcs & BCM2708_DMA_ACTIVE) && (ch->cs & BCM2708_DMA_ACTIVE)) { bcm2835_dma_update(s, c); } break; case BCM2708_DMA_ADDR: ch->conblk_ad = value; break; case BCM2708_DMA_DEBUG: ch->debug = value; break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", __func__, offset); break; } } static uint64_t bcm2835_dma0_read(void *opaque, hwaddr offset, unsigned size) { BCM2835DMAState *s = opaque; if (offset < 0xf00) { return bcm2835_dma_read(s, (offset & 0xff), size, (offset >> 8) & 0xf); } else { switch (offset) { case BCM2708_DMA_INT_STATUS: return s->int_status; case BCM2708_DMA_ENABLE: return s->enable; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", __func__, offset); return 0; } } } static uint64_t bcm2835_dma15_read(void *opaque, hwaddr offset, unsigned size) { return bcm2835_dma_read(opaque, (offset & 0xff), size, 15); } static void bcm2835_dma0_write(void *opaque, hwaddr offset, uint64_t value, unsigned size) { BCM2835DMAState *s = opaque; if (offset < 0xf00) { bcm2835_dma_write(s, (offset & 0xff), value, size, (offset >> 8) & 0xf); } else { switch (offset) { case BCM2708_DMA_INT_STATUS: break; case BCM2708_DMA_ENABLE: s->enable = (value & 0xffff); break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n", __func__, offset); } } } static void bcm2835_dma15_write(void *opaque, hwaddr offset, uint64_t value, unsigned size) { bcm2835_dma_write(opaque, (offset & 0xff), value, size, 15); } static const MemoryRegionOps bcm2835_dma0_ops = { .read = bcm2835_dma0_read, .write = bcm2835_dma0_write, .endianness = DEVICE_NATIVE_ENDIAN, .valid.min_access_size = 4, .valid.max_access_size = 4, }; static const MemoryRegionOps bcm2835_dma15_ops = { .read = bcm2835_dma15_read, .write = bcm2835_dma15_write, .endianness = DEVICE_NATIVE_ENDIAN, .valid.min_access_size = 4, .valid.max_access_size = 4, }; static const VMStateDescription vmstate_bcm2835_dma_chan = { .name = TYPE_BCM2835_DMA "-chan", .version_id = 1, .minimum_version_id = 1, .fields = (VMStateField[]) { VMSTATE_UINT32(cs, BCM2835DMAChan), VMSTATE_UINT32(conblk_ad, BCM2835DMAChan), VMSTATE_UINT32(ti, BCM2835DMAChan), VMSTATE_UINT32(source_ad, BCM2835DMAChan), VMSTATE_UINT32(dest_ad, BCM2835DMAChan), VMSTATE_UINT32(txfr_len, BCM2835DMAChan), VMSTATE_UINT32(stride, BCM2835DMAChan), VMSTATE_UINT32(nextconbk, BCM2835DMAChan), VMSTATE_UINT32(debug, BCM2835DMAChan), VMSTATE_END_OF_LIST() } }; static const VMStateDescription vmstate_bcm2835_dma = { .name = TYPE_BCM2835_DMA, .version_id = 1, .minimum_version_id = 1, .fields = (VMStateField[]) { VMSTATE_STRUCT_ARRAY(chan, BCM2835DMAState, BCM2835_DMA_NCHANS, 1, vmstate_bcm2835_dma_chan, BCM2835DMAChan), VMSTATE_UINT32(int_status, BCM2835DMAState), VMSTATE_UINT32(enable, BCM2835DMAState), VMSTATE_END_OF_LIST() } }; static void bcm2835_dma_init(Object *obj) { BCM2835DMAState *s = BCM2835_DMA(obj); int n; /* DMA channels 0-14 occupy a contiguous block of IO memory, along * with the global enable and interrupt status bits. Channel 15 * has the same register map, but is mapped at a discontiguous * address in a separate IO block. */ memory_region_init_io(&s->iomem0, OBJECT(s), &bcm2835_dma0_ops, s, TYPE_BCM2835_DMA, 0x1000); sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem0); memory_region_init_io(&s->iomem15, OBJECT(s), &bcm2835_dma15_ops, s, TYPE_BCM2835_DMA "-chan15", 0x100); sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem15); for (n = 0; n < 16; n++) { sysbus_init_irq(SYS_BUS_DEVICE(s), &s->chan[n].irq); } } static void bcm2835_dma_reset(DeviceState *dev) { BCM2835DMAState *s = BCM2835_DMA(dev); int n; s->enable = 0xffff; s->int_status = 0; for (n = 0; n < BCM2835_DMA_NCHANS; n++) { bcm2835_dma_chan_reset(&s->chan[n]); } } static void bcm2835_dma_realize(DeviceState *dev, Error **errp) { BCM2835DMAState *s = BCM2835_DMA(dev); Error *err = NULL; Object *obj; obj = object_property_get_link(OBJECT(dev), "dma-mr", &err); if (obj == NULL) { error_setg(errp, "%s: required dma-mr link not found: %s", __func__, error_get_pretty(err)); return; } s->dma_mr = MEMORY_REGION(obj); address_space_init(&s->dma_as, s->dma_mr, NULL); bcm2835_dma_reset(dev); } static void bcm2835_dma_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); dc->realize = bcm2835_dma_realize; dc->reset = bcm2835_dma_reset; dc->vmsd = &vmstate_bcm2835_dma; } static TypeInfo bcm2835_dma_info = { .name = TYPE_BCM2835_DMA, .parent = TYPE_SYS_BUS_DEVICE, .instance_size = sizeof(BCM2835DMAState), .class_init = bcm2835_dma_class_init, .instance_init = bcm2835_dma_init, }; static void bcm2835_dma_register_types(void) { type_register_static(&bcm2835_dma_info); } type_init(bcm2835_dma_register_types)