diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c index de9746665d..c8a11f2b53 100644 --- a/hw/arm/armv7m.c +++ b/hw/arm/armv7m.c @@ -23,103 +23,73 @@ /* Bitbanded IO. Each word corresponds to a single bit. */ /* Get the byte address of the real memory for a bitband access. */ -static inline uint32_t bitband_addr(void * opaque, uint32_t addr) +static inline hwaddr bitband_addr(BitBandState *s, hwaddr offset) { - uint32_t res; - - res = *(uint32_t *)opaque; - res |= (addr & 0x1ffffff) >> 5; - return res; - + return s->base | (offset & 0x1ffffff) >> 5; } -static uint32_t bitband_readb(void *opaque, hwaddr offset) +static MemTxResult bitband_read(void *opaque, hwaddr offset, + uint64_t *data, unsigned size, MemTxAttrs attrs) { - uint8_t v; - cpu_physical_memory_read(bitband_addr(opaque, offset), &v, 1); - return (v & (1 << ((offset >> 2) & 7))) != 0; + BitBandState *s = opaque; + uint8_t buf[4]; + MemTxResult res; + int bitpos, bit; + hwaddr addr; + + assert(size <= 4); + + /* Find address in underlying memory and round down to multiple of size */ + addr = bitband_addr(s, offset) & (-size); + res = address_space_read(s->source_as, addr, attrs, buf, size); + if (res) { + return res; + } + /* Bit position in the N bytes read... */ + bitpos = (offset >> 2) & ((size * 8) - 1); + /* ...converted to byte in buffer and bit in byte */ + bit = (buf[bitpos >> 3] >> (bitpos & 7)) & 1; + *data = bit; + return MEMTX_OK; } -static void bitband_writeb(void *opaque, hwaddr offset, - uint32_t value) +static MemTxResult bitband_write(void *opaque, hwaddr offset, uint64_t value, + unsigned size, MemTxAttrs attrs) { - uint32_t addr; - uint8_t mask; - uint8_t v; - addr = bitband_addr(opaque, offset); - mask = (1 << ((offset >> 2) & 7)); - cpu_physical_memory_read(addr, &v, 1); - if (value & 1) - v |= mask; - else - v &= ~mask; - cpu_physical_memory_write(addr, &v, 1); -} + BitBandState *s = opaque; + uint8_t buf[4]; + MemTxResult res; + int bitpos, bit; + hwaddr addr; -static uint32_t bitband_readw(void *opaque, hwaddr offset) -{ - uint32_t addr; - uint16_t mask; - uint16_t v; - addr = bitband_addr(opaque, offset) & ~1; - mask = (1 << ((offset >> 2) & 15)); - mask = tswap16(mask); - cpu_physical_memory_read(addr, &v, 2); - return (v & mask) != 0; -} + assert(size <= 4); -static void bitband_writew(void *opaque, hwaddr offset, - uint32_t value) -{ - uint32_t addr; - uint16_t mask; - uint16_t v; - addr = bitband_addr(opaque, offset) & ~1; - mask = (1 << ((offset >> 2) & 15)); - mask = tswap16(mask); - cpu_physical_memory_read(addr, &v, 2); - if (value & 1) - v |= mask; - else - v &= ~mask; - cpu_physical_memory_write(addr, &v, 2); -} - -static uint32_t bitband_readl(void *opaque, hwaddr offset) -{ - uint32_t addr; - uint32_t mask; - uint32_t v; - addr = bitband_addr(opaque, offset) & ~3; - mask = (1 << ((offset >> 2) & 31)); - mask = tswap32(mask); - cpu_physical_memory_read(addr, &v, 4); - return (v & mask) != 0; -} - -static void bitband_writel(void *opaque, hwaddr offset, - uint32_t value) -{ - uint32_t addr; - uint32_t mask; - uint32_t v; - addr = bitband_addr(opaque, offset) & ~3; - mask = (1 << ((offset >> 2) & 31)); - mask = tswap32(mask); - cpu_physical_memory_read(addr, &v, 4); - if (value & 1) - v |= mask; - else - v &= ~mask; - cpu_physical_memory_write(addr, &v, 4); + /* Find address in underlying memory and round down to multiple of size */ + addr = bitband_addr(s, offset) & (-size); + res = address_space_read(s->source_as, addr, attrs, buf, size); + if (res) { + return res; + } + /* Bit position in the N bytes read... */ + bitpos = (offset >> 2) & ((size * 8) - 1); + /* ...converted to byte in buffer and bit in byte */ + bit = 1 << (bitpos & 7); + if (value & 1) { + buf[bitpos >> 3] |= bit; + } else { + buf[bitpos >> 3] &= ~bit; + } + return address_space_write(s->source_as, addr, attrs, buf, size); } static const MemoryRegionOps bitband_ops = { - .old_mmio = { - .read = { bitband_readb, bitband_readw, bitband_readl, }, - .write = { bitband_writeb, bitband_writew, bitband_writel, }, - }, + .read_with_attrs = bitband_read, + .write_with_attrs = bitband_write, .endianness = DEVICE_NATIVE_ENDIAN, + .impl.min_access_size = 1, + .impl.max_access_size = 4, + .valid.min_access_size = 1, + .valid.max_access_size = 4, }; static void bitband_init(Object *obj) @@ -127,11 +97,30 @@ static void bitband_init(Object *obj) BitBandState *s = BITBAND(obj); SysBusDevice *dev = SYS_BUS_DEVICE(obj); - memory_region_init_io(&s->iomem, obj, &bitband_ops, &s->base, + object_property_add_link(obj, "source-memory", + TYPE_MEMORY_REGION, + (Object **)&s->source_memory, + qdev_prop_allow_set_link_before_realize, + OBJ_PROP_LINK_UNREF_ON_RELEASE, + &error_abort); + memory_region_init_io(&s->iomem, obj, &bitband_ops, s, "bitband", 0x02000000); sysbus_init_mmio(dev, &s->iomem); } +static void bitband_realize(DeviceState *dev, Error **errp) +{ + BitBandState *s = BITBAND(dev); + + if (!s->source_memory) { + error_setg(errp, "source-memory property not set"); + return; + } + + s->source_as = address_space_init_shareable(s->source_memory, + "bitband-source"); +} + /* Board init. */ static const hwaddr bitband_input_addr[ARMV7M_NUM_BITBANDS] = { @@ -250,6 +239,8 @@ static void armv7m_realize(DeviceState *dev, Error **errp) error_propagate(errp, err); return; } + object_property_set_link(obj, OBJECT(s->board_memory), + "source-memory", &error_abort); object_property_set_bool(obj, true, "realized", &err); if (err != NULL) { error_propagate(errp, err); @@ -365,6 +356,7 @@ static void bitband_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); + dc->realize = bitband_realize; dc->props = bitband_properties; } diff --git a/include/hw/arm/armv7m.h b/include/hw/arm/armv7m.h index 3333c91e88..a9b3f2ab35 100644 --- a/include/hw/arm/armv7m.h +++ b/include/hw/arm/armv7m.h @@ -21,8 +21,10 @@ typedef struct { SysBusDevice parent_obj; /*< public >*/ + AddressSpace *source_as; MemoryRegion iomem; uint32_t base; + MemoryRegion *source_memory; } BitBandState; #define TYPE_ARMV7M "armv7m"