__reserved_mem_reserve_reg() won't reserve memory if the base address is zero. This change removes the check for a base address of zero and allows it to be reserved.
Allowing the first 4K of memory to be reserved will help solve a problem on some ARM systems where the the first 16K of memory is unused and becomes allocable memory. This will prevent this memory from being used for DMA by drivers like the USB OHCI driver which consider a physical address of zero to be illegal. Signed-off-by: Al Cooper <[email protected]> --- drivers/of/fdt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 9aa012e..379ad4f 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -453,7 +453,7 @@ static int __init __reserved_mem_reserve_reg(unsigned long node, base = dt_mem_next_cell(dt_root_addr_cells, &prop); size = dt_mem_next_cell(dt_root_size_cells, &prop); - if (base && size && + if (size && early_init_dt_reserve_memory_arch(base, size, nomap) == 0) pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n", uname, &base, (unsigned long)size / SZ_1M); -- 1.9.0.138.g2de3478 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
