Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2d5a5612 authored by Catalin Marinas's avatar Catalin Marinas
Browse files

arm64: Limit the CMA buffer to 32-bit if ZONE_DMA 



When the CMA buffer is allocated, it is too early to know whether
devices will require ZONE_DMA memory. This patch limits the CMA buffer
to (DMA_BIT_MASK(32) + 1) if CONFIG_ZONE_DMA is enabled.

In addition, it computes the dma_to_phys(DMA_BIT_MASK(32)) before the
increment (no current functional change).

Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 1712ef43

arch/arm64/mm/init.c

+8 −2
Original line number Diff line number Diff line
@@ -71,7 +71,7 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max) 
	/* 4GB maximum for 32-bit only capable devices */

	if (IS_ENABLED(CONFIG_ZONE_DMA)) {

		unsigned long max_dma_phys =

			(unsigned long)dma_to_phys(NULL, DMA_BIT_MASK(32) + 1);

			(unsigned long)(dma_to_phys(NULL, DMA_BIT_MASK(32)) + 1);

		max_dma = max(min, min(max, max_dma_phys >> PAGE_SHIFT));

		zone_size[ZONE_DMA] = max_dma - min;

	}
@@ -126,6 +126,8 @@ static void arm64_memory_present(void) 


void __init arm64_memblock_init(void)

{

	phys_addr_t dma_phys_limit = 0;



	/* Register the kernel text, kernel data and initrd with memblock */

	memblock_reserve(__pa(_text), _end - _text);

#ifdef CONFIG_BLK_DEV_INITRD
@@ -141,7 +143,11 @@ void __init arm64_memblock_init(void) 
	memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);



	early_init_fdt_scan_reserved_mem();

	dma_contiguous_reserve(0);



	/* 4GB maximum for 32-bit only capable devices */

	if (IS_ENABLED(CONFIG_ZONE_DMA))

		dma_phys_limit = dma_to_phys(NULL, DMA_BIT_MASK(32)) + 1;

	dma_contiguous_reserve(dma_phys_limit);



	memblock_allow_resize();

	memblock_dump_all();