On 05/03/2015 23:13, Hervé Poussineau wrote:
> +static const MemoryRegionOps rc4030_dma_tt_ops = {
> + .impl.min_access_size = 4,
> + .impl.max_access_size = 4,
> + .impl.max_access_size = 4,
> +};
> +
> +static void rc4030_dma_tt_update(rc4030State *s, uint32_t new_tl_base,
> + uint32_t new_tl_limit)
> +{
> + int entries, i;
> + dma_pagetable_entry *dma_tl_contents;
> +
> + if (s->dma_tl_limit) {
> + /* write old dma tl table to physical memory */
> + memory_region_del_subregion(get_system_memory(), &s->dma_tt);
> + cpu_physical_memory_write(s->dma_tl_limit & 0x7fffffff,
> + memory_region_get_ram_ptr(&s->dma_tt),
> + s->dma_tl_limit);
You would need object_unparent(&s->dma_tt) here.
However, this breaks the rules for memory region lifetime (see
docs/memory.txt).
One solution is to warn here for a large dma_tl_limit and always create
a 4K ROMD region. Here you can create an alias into the actual dma_tt
region and add/remove/unparent that alias. Aliases can be created and
unparented at will.
> @@ -733,7 +793,16 @@ static void rc4030_do_dma(void *opaque, int n, uint8_t
> *buf, int len, int is_wri
> dma_addr = s->dma_regs[n][DMA_REG_ADDRESS];
>
> /* Read/write data at right place */
> - rc4030_dma_memory_rw(opaque, dma_addr, buf, len, is_write);
> + for (i = 0; i < len; ) {
> + int ncpy = DMA_PAGESIZE - (dma_addr & (DMA_PAGESIZE - 1));
> + if (ncpy > len - i) {
> + ncpy = len - i;
> + }
> + address_space_rw(&s->dma_as, dma_addr, buf + i, ncpy, is_write);
> +
> + dma_addr += ncpy;
> + i += ncpy;
> + }
>
> s->dma_regs[n][DMA_REG_ENABLE] |= DMA_FLAG_TC_INTR;
> s->dma_regs[n][DMA_REG_COUNT] -= len;
The loop should not be necessary, address_space_rw does the same.
Paolo
> @@ -800,6 +869,7 @@ void *rc4030_init(qemu_irq timer, qemu_irq jazz_bus,
> MemoryRegion *sysmem)
> {
> rc4030State *s;
> + int i;
>
> s = g_malloc0(sizeof(rc4030State));
>
> @@ -821,5 +891,15 @@ void *rc4030_init(qemu_irq timer, qemu_irq jazz_bus,
> "rc4030.jazzio", 0x00001000);
> memory_region_add_subregion(sysmem, 0xf0000000, &s->iomem_jazzio);
>
> + memory_region_init(&s->dma_tt, NULL, "dma_tt", 0);
> + memory_region_init(&s->dma_mr, NULL, "dma", INT32_MAX);
> + for (i = 0; i < MAX_TL_ENTRIES; ++i) {
> + memory_region_init_alias(&s->dma_mrs[i], NULL, "dma-alias",
> + get_system_memory(), 0, DMA_PAGESIZE);
> + memory_region_set_enabled(&s->dma_mrs[i], false);
> + memory_region_add_subregion(&s->dma_mr, i * DMA_PAGESIZE,
> + &s->dma_mrs[i]);
> + }
> + address_space_init(&s->dma_as, &s->dma_mr, "rc4030_dma");
> return s;
> }
>
