1 files changed, 30 insertions, 36 deletions

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index d0b4c2efda9..e90c5426fe1 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -30,6 +30,7 @@
 #include <linux/memblock.h>
 #include <linux/sort.h>
 #include <linux/of_fdt.h>
+#include <linux/dma-mapping.h>
 #include <linux/dma-contiguous.h>
 
 #include <asm/sections.h>
@@ -59,22 +60,31 @@ static int __init early_initrd(char *p)
 early_param("initrd", early_initrd);
 #endif
 
-#define MAX_DMA32_PFN ((4UL * 1024 * 1024 * 1024) >> PAGE_SHIFT)
+/*
+ * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
+ * currently assumes that for memory starting above 4G, 32-bit devices will
+ * use a DMA offset.
+ */
+static phys_addr_t max_zone_dma_phys(void)
+{
+	phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
+	return min(offset + (1ULL << 32), memblock_end_of_DRAM());
+}
 
 static void __init zone_sizes_init(unsigned long min, unsigned long max)
 {
 	struct memblock_region *reg;
 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
-	unsigned long max_dma32 = min;
+	unsigned long max_dma = min;
 
 	memset(zone_size, 0, sizeof(zone_size));
 
-#ifdef CONFIG_ZONE_DMA32
 	/* 4GB maximum for 32-bit only capable devices */
-	max_dma32 = max(min, min(max, MAX_DMA32_PFN));
-	zone_size[ZONE_DMA32] = max_dma32 - min;
-#endif
-	zone_size[ZONE_NORMAL] = max - max_dma32;
+	if (IS_ENABLED(CONFIG_ZONE_DMA)) {
+		max_dma = PFN_DOWN(max_zone_dma_phys());
+		zone_size[ZONE_DMA] = max_dma - min;
+	}
+	zone_size[ZONE_NORMAL] = max - max_dma;
 
 	memcpy(zhole_size, zone_size, sizeof(zhole_size));
 
@@ -84,15 +94,15 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max)
 
 		if (start >= max)
 			continue;
-#ifdef CONFIG_ZONE_DMA32
-		if (start < max_dma32) {
-			unsigned long dma_end = min(end, max_dma32);
-			zhole_size[ZONE_DMA32] -= dma_end - start;
+
+		if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
+			unsigned long dma_end = min(end, max_dma);
+			zhole_size[ZONE_DMA] -= dma_end - start;
 		}
-#endif
-		if (end > max_dma32) {
+
+		if (end > max_dma) {
 			unsigned long normal_end = min(end, max);
-			unsigned long normal_start = max(start, max_dma32);
+			unsigned long normal_start = max(start, max_dma);
 			zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
 		}
 	}
@@ -125,7 +135,7 @@ static void arm64_memory_present(void)
 
 void __init arm64_memblock_init(void)
 {
-	u64 *reserve_map, base, size;
+	phys_addr_t dma_phys_limit = 0;
 
 	/* Register the kernel text, kernel data and initrd with memblock */
 	memblock_reserve(__pa(_text), _end - _text);
@@ -141,26 +151,12 @@ void __init arm64_memblock_init(void)
 	memblock_reserve(__pa(swapper_pg_dir), SWAPPER_DIR_SIZE);
 	memblock_reserve(__pa(idmap_pg_dir), IDMAP_DIR_SIZE);
 
-	/* Reserve the dtb region */
-	memblock_reserve(virt_to_phys(initial_boot_params),
-			 be32_to_cpu(initial_boot_params->totalsize));
+	early_init_fdt_scan_reserved_mem();
 
-	/*
-	 * Process the reserve map.  This will probably overlap the initrd
-	 * and dtb locations which are already reserved, but overlapping
-	 * doesn't hurt anything
-	 */
-	reserve_map = ((void*)initial_boot_params) +
-			be32_to_cpu(initial_boot_params->off_mem_rsvmap);
-	while (1) {
-		base = be64_to_cpup(reserve_map++);
-		size = be64_to_cpup(reserve_map++);
-		if (!size)
-			break;
-		memblock_reserve(base, size);
-	}
-
-	dma_contiguous_reserve(0);
+	/* 4GB maximum for 32-bit only capable devices */
+	if (IS_ENABLED(CONFIG_ZONE_DMA))
+		dma_phys_limit = max_zone_dma_phys();
+	dma_contiguous_reserve(dma_phys_limit);
 
 	memblock_allow_resize();
 	memblock_dump_all();
@@ -261,8 +257,6 @@ static void __init free_unused_memmap(void)
  */
 void __init mem_init(void)
 {
-	arm64_swiotlb_init();
-
 	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
 
 #ifndef CONFIG_SPARSEMEM_VMEMMAP