From d0a9b5bc0a6abdab182ad55dcc1c71508c163c5c Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 8 Aug 2011 19:58:49 +0300 Subject: [PATCH] memory: add API for creating ROM/device regions ROM/device regions act as mapped RAM for reads, can I/O memory for writes. This allow emulation of flash devices. Signed-off-by: Avi Kivity Signed-off-by: Anthony Liguori --- memory.c | 46 ++++++++++++++++++++++++++++++++++++++++++++-- memory.h | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 2 deletions(-) diff --git a/memory.c b/memory.c index 5e3d96694b..beff98c35b 100644 --- a/memory.c +++ b/memory.c @@ -125,6 +125,7 @@ struct FlatRange { target_phys_addr_t offset_in_region; AddrRange addr; uint8_t dirty_log_mask; + bool readable; }; /* Flattened global view of current active memory hierarchy. Kept in sorted @@ -164,7 +165,8 @@ static bool flatrange_equal(FlatRange *a, FlatRange *b) { return a->mr == b->mr && addrrange_equal(a->addr, b->addr) - && a->offset_in_region == b->offset_in_region; + && a->offset_in_region == b->offset_in_region + && a->readable == b->readable; } static void flatview_init(FlatView *view) @@ -200,7 +202,8 @@ static bool can_merge(FlatRange *r1, FlatRange *r2) return addrrange_end(r1->addr) == r2->addr.start && r1->mr == r2->mr && r1->offset_in_region + r1->addr.size == r2->offset_in_region - && r1->dirty_log_mask == r2->dirty_log_mask; + && r1->dirty_log_mask == r2->dirty_log_mask + && r1->readable == r2->readable; } /* Attempt to simplify a view by merging ajacent ranges */ @@ -241,6 +244,10 @@ static void as_memory_range_add(AddressSpace *as, FlatRange *fr) region_offset = 0; } + if (!fr->readable) { + phys_offset &= TARGET_PAGE_MASK; + } + cpu_register_physical_memory_log(fr->addr.start, fr->addr.size, phys_offset, @@ -462,6 +469,7 @@ static void render_memory_region(FlatView *view, fr.offset_in_region = offset_in_region; fr.addr = addrrange_make(base, now); fr.dirty_log_mask = mr->dirty_log_mask; + fr.readable = mr->readable; flatview_insert(view, i, &fr); ++i; base += now; @@ -480,6 +488,7 @@ static void render_memory_region(FlatView *view, fr.offset_in_region = offset_in_region; fr.addr = addrrange_make(base, remain); fr.dirty_log_mask = mr->dirty_log_mask; + fr.readable = mr->readable; flatview_insert(view, i, &fr); } } @@ -680,6 +689,12 @@ static void memory_region_destructor_iomem(MemoryRegion *mr) cpu_unregister_io_memory(mr->ram_addr); } +static void memory_region_destructor_rom_device(MemoryRegion *mr) +{ + qemu_ram_free(mr->ram_addr & TARGET_PAGE_MASK); + cpu_unregister_io_memory(mr->ram_addr & ~(TARGET_PAGE_MASK | IO_MEM_ROMD)); +} + void memory_region_init(MemoryRegion *mr, const char *name, uint64_t size) @@ -690,6 +705,7 @@ void memory_region_init(MemoryRegion *mr, mr->addr = 0; mr->offset = 0; mr->terminates = false; + mr->readable = true; mr->destructor = memory_region_destructor_none; mr->priority = 0; mr->may_overlap = false; @@ -910,6 +926,24 @@ void memory_region_init_alias(MemoryRegion *mr, mr->alias_offset = offset; } +void memory_region_init_rom_device(MemoryRegion *mr, + const MemoryRegionOps *ops, + DeviceState *dev, + const char *name, + uint64_t size) +{ + memory_region_init(mr, name, size); + mr->terminates = true; + mr->destructor = memory_region_destructor_rom_device; + mr->ram_addr = qemu_ram_alloc(dev, name, size); + mr->ram_addr |= cpu_register_io_memory(memory_region_read_thunk, + memory_region_write_thunk, + mr, + mr->ops->endianness); + mr->ram_addr |= IO_MEM_ROMD; + mr->backend_registered = true; +} + void memory_region_destroy(MemoryRegion *mr) { assert(QTAILQ_EMPTY(&mr->subregions)); @@ -967,6 +1001,14 @@ void memory_region_set_readonly(MemoryRegion *mr, bool readonly) /* FIXME */ } +void memory_region_rom_device_set_readable(MemoryRegion *mr, bool readable) +{ + if (mr->readable != readable) { + mr->readable = readable; + memory_region_update_topology(); + } +} + void memory_region_reset_dirty(MemoryRegion *mr, target_phys_addr_t addr, target_phys_addr_t size, unsigned client) { diff --git a/memory.h b/memory.h index c9252a245d..0553cc7526 100644 --- a/memory.h +++ b/memory.h @@ -113,6 +113,7 @@ struct MemoryRegion { ram_addr_t ram_addr; IORange iorange; bool terminates; + bool readable; MemoryRegion *alias; target_phys_addr_t alias_offset; unsigned priority; @@ -219,6 +220,25 @@ void memory_region_init_alias(MemoryRegion *mr, MemoryRegion *orig, target_phys_addr_t offset, uint64_t size); + +/** + * memory_region_init_rom_device: Initialize a ROM memory region. Writes are + * handled via callbacks. + * + * @mr: the #MemoryRegion to be initialized. + * @ops: callbacks for write access handling. + * @dev: a device associated with the region; may be %NULL. + * @name: the name of the region; the pair (@dev, @name) must be globally + * unique. The name is part of the save/restore ABI and so cannot be + * changed. + * @size: size of the region. + */ +void memory_region_init_rom_device(MemoryRegion *mr, + const MemoryRegionOps *ops, + DeviceState *dev, /* FIXME: layering violation */ + const char *name, + uint64_t size); + /** * memory_region_destroy: Destroy a memory region and relaim all resources. * @@ -330,6 +350,20 @@ void memory_region_reset_dirty(MemoryRegion *mr, target_phys_addr_t addr, */ void memory_region_set_readonly(MemoryRegion *mr, bool readonly); +/** + * memory_region_rom_device_set_readable: enable/disable ROM readability + * + * Allows a ROM device (initialized with memory_region_init_rom_device() to + * to be marked as readable (default) or not readable. When it is readable, + * the device is mapped to guest memory. When not readable, reads are + * forwarded to the #MemoryRegion.read function. + * + * @mr: the memory region to be updated + * @readable: whether reads are satisified directly (%true) or via callbacks + * (%false) + */ +void memory_region_rom_device_set_readable(MemoryRegion *mr, bool readable); + /** * memory_region_set_coalescing: Enable memory coalescing for the region. *