//start_kernel()->setup_arch()->early_init_dt_scan_nodes()->early_init_dt_scan_memory()
//从dts文件中加载物理内存
early_init_dt_scan_memory()
{
	early_init_dt_add_memory_arch(base=0x80000000, size=0x40000000);
}
void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
{
	memblock_add(base, size);
}
int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
{
	printk("---->>memblock_add() base=%#lx , size=%d kb\n",(unsigned long)base,size/1024);
	return memblock_add_range(&memblock.memory, base, size,
				   MAX_NUMNODES, 0);
}
//---->>memblock_add() base=0x80000000 , size=1048576 kb
//可以看到物理内存是1G

asmlinkage __visible void __init start_kernel(void)
{
	.....
	setup_arch(&command_line);
	.....
}

void __init setup_arch(char **cmdline_p)
{
	.....
	sanity_check_meminfo();
	arm_memblock_init(mdesc);
	.....
}

void __init arm_memblock_init(const struct machine_desc *mdesc)
{
	......
	arm_mm_memblock_reserve();
	early_init_fdt_scan_reserved_mem();
	dma_contiguous_reserve(arm_dma_limit);
	......
}


int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
					phys_addr_t size, bool nomap)
{
	//如果是no-map属性的就从memblock中移除
	if (nomap)
		return memblock_remove(base, size);
	//非no-map属性的添加到reserve中
	return memblock_reserve(base, size);
}

void __init arm_memblock_init(const struct machine_desc *mdesc)
{
	//大概21953K
	#ifdef CONFIG_XIP_KERNEL
	memblock_reserve(__pa(_sdata), _end - _sdata);
	#else
	memblock_reserve(__pa(_stext), _end - _stext);
	#endif
	//大概1782K
	memblock_reserve(phys_initrd_start, phys_initrd_size);
	
	//大概16K
	//arm_mm_memblock_reserve()->memblock_reserve()
	memblock_reserve(__pa(swapper_pg_dir), SWAPPER_PG_DIR_SIZE);
	
	//大概213K
	//start_kernel()->setup_arch()->arm_memblock_init()->early_init_fdt_scan_reserved_mem()->early_init_dt_reserve_memory_arch()
	early_init_dt_reserve_memory_arch(__pa(initial_boot_params),fdt_totalsize(initial_boot_params),0);
}

//MEMORY(1)
//start_kernel()->setup_arch()->paging_init()
void __init paging_init(const struct machine_desc *mdesc)
{
	....
	//调用early_alloc_aligned()使用memblock分配内存，这块内存从memory列表移除添加到reserve列表中
	map_lowmem();
	
	//调用early_alloc_aligned()使用memblock分配内存，这块内存从memory列表移除添加到reserve列表中
	dma_contiguous_remap();
	
	//调用create_mapping->alloc_init_pud()->alloc_init_pmd->alloc_init_pte()->early_pte_alloc()->early_alloc()->early_alloc_aligned()->memblock_alloc()分配内存
	early_ioremap_reset();
	
	//调用early_alloc(PAGE_SIZE * 2); + create_mapping(&map);分配内存
	devicemaps_init();
	
	//early_pte_alloc()分配pte
	kmap_init();
	{
		#ifdef CONFIG_HIGHMEM
		pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),PKMAP_BASE, _PAGE_KERNEL_TABLE);
		#endif
		early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START,_PAGE_KERNEL_TABLE);
	}
	
	//分配0号page
	zero_page = early_alloc(PAGE_SIZE);
	
	//
	bootmem_init();
	{
		zone_sizes_init();
		{
			free_area_init_node();
			{
				//alloc_node_mem_map()->memblock_virt_alloc_node_nopanic()->memblock_virt_alloc_try_nid_nopanic()->memblock_virt_alloc_internal()->memblock_reserve()
				alloc_node_mem_map();
				
				//free_area_init_core()->setup_usemap()->memblock_virt_alloc_node_nopanic()->memblock_virt_alloc_try_nid_nopanic()->memblock_virt_alloc_internal()->memblock_reserve()
				free_area_init_core(pgdat, start_pfn, end_pfn,zones_size, zholes_size);
			}
		}
	}


	....
}

//start_kernel()->setup_arch()->request_standard_resources()
static void __init request_standard_resources(const struct machine_desc *mdesc)
{
	....
	struct resource *res;
	....
	for_each_memblock(memory, region) {
		....
		res = memblock_virt_alloc(sizeof(*res), 0);
		....
		}
	....
}

//start_kernel()->setup_command_line()
static void __init setup_command_line(char *command_line)
{
	saved_command_line =
		memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
	initcall_command_line =
		memblock_virt_alloc(strlen(boot_command_line) + 1, 0);
	static_command_line = memblock_virt_alloc(strlen(command_line) + 1, 0);
	strcpy(saved_command_line, boot_command_line);
	strcpy(static_command_line, command_line);
}

//start_kernel()->vfs_caches_init_early()
void __init vfs_caches_init_early(void)
{
	dcache_init_early();
	inode_init_early();
}
//类似于PID
//Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
static void __init dcache_init_early(void)
{
	dentry_hashtable =
		alloc_large_system_hash("Dentry cache",
					sizeof(struct hlist_bl_head),
					dhash_entries,
					13,
					HASH_EARLY,
					&d_hash_shift,
					&d_hash_mask,
					0,
					0);
}

//Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
void __init inode_init_early(void)
{
	inode_hashtable =
		alloc_large_system_hash("Inode-cache",
					sizeof(struct hlist_head),
					ihash_entries,
					14,
					HASH_EARLY,
					&i_hash_shift,
					&i_hash_mask,
					0,
					0);
}

core_initcall(cma_init_reserved_areas);
static int __init cma_init_reserved_areas(void)
{
	for (i = 0; i < cma_area_count; i++) {
		int ret = cma_activate_area(&cma_areas[i]);
	}
}




static int __init cma_activate_area(struct cma *cma)
{
	init_cma_reserved_pageblock(pfn_to_page(base_pfn));
}


void __init init_cma_reserved_pageblock(struct page *page)
{
	....
	set_pageblock_migratetype(page, MIGRATE_CMA);
	....
	adjust_managed_page_count(page, pageblock_nr_pages);
	....
}


void adjust_managed_page_count(struct page *page, long count)
{
	spin_lock(&managed_page_count_lock);
	page_zone(page)->managed_pages += count;
	totalram_pages += count;
#ifdef CONFIG_HIGHMEM
	if (PageHighMem(page))
		totalhigh_pages += count;
#endif
	spin_unlock(&managed_page_count_lock);

}

rootfs_initcall(populate_rootfs);
static int __init populate_rootfs(void)
{
	err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
	if (initrd_start) {
#ifdef CONFIG_BLK_DEV_RAM
		
		err = unpack_to_rootfs((char *)initrd_start,
			initrd_end - initrd_start);
		if (!err) {
			free_initrd();
			goto done;
		} else {
			clean_rootfs();
			unpack_to_rootfs(__initramfs_start, __initramfs_size);
		}
		fd = sys_open("/initrd.image", O_WRONLY|O_CREAT, 0700);
		if (fd >= 0) {
			sys_close(fd);
			free_initrd();
		}
	done:
#else

		err = unpack_to_rootfs((char *)initrd_start,initrd_end - initrd_start);

		free_initrd();
#endif
}

static void __init free_initrd(void)
{
	free_initrd_mem(initrd_start, initrd_end);
}

void free_initrd_mem(unsigned long start, unsigned long end)
{
	free_reserved_area((void *)start, (void *)end, -1, "initrd");
}

unsigned long free_reserved_area(void *start, void *end, int poison, char *s)
{
	start = (void *)PAGE_ALIGN((unsigned long)start);
	end = (void *)((unsigned long)end & PAGE_MASK);
	for (pos = start; pos < end; pos += PAGE_SIZE, pages++) {
		if ((unsigned int)poison <= 0xFF)
			memset(pos, poison, PAGE_SIZE);
		free_reserved_page(virt_to_page(pos));
	}

	if (pages && s)
		pr_info("Freeing %s memory: %ldK (%p - %p)\n",
			s, pages << (PAGE_SHIFT - 10), start, end);
}

static void removed_region_fixup(struct removed_region *dma_mem, int index)
{
	//把modem这块内存释放出来从reserve变成memory[0M , 80M]
	memblock_free(dma_mem->base, dma_mem->nr_pages * PAGE_SIZE);
	//把modem这块内存[0M , 75M]从内存管理移除
	memblock_remove(dma_mem->base, index * PAGE_SIZE);

	//释放掉modem使用的page内存
	free_memmap(base_pfn, base_pfn + index);
	//释放掉modem的[75M , 80M]这5M内存
	free_bootmem_late(dma_mem->base + index * PAGE_SIZE, fixup_size);
	
}

int mdss_mdp_splash_cleanup(struct msm_fb_data_type *mfd,
					bool use_borderfill)
{
	memblock_free(mdp5_data->splash_mem_addr,mdp5_data->splash_mem_size);
}