ARC: mm: HIGHMEM: populate high memory from DT (29e33226) · Commits · e / devices / android_kernel_teracube_mt6765

arch/arc/boot/dts/nsim_hs.dts

+10 −2

Original line number	Diff line number	Diff line
		@@ -11,8 +11,16 @@

		/ {
		compatible = "snps,nsim_hs";
		#address-cells = <2>;
		#size-cells = <2>;
		interrupt-parent = <&core_intc>;

		memory {
		device_type = "memory";
		reg = <0x0 0x80000000 0x0 0x40000000 /* 1 GB low mem */
		0x1 0x00000000 0x0 0x40000000>; /* 1 GB highmem */
		};

		chosen {
		bootargs = "earlycon=arc_uart,mmio32,0xc0fc1000,115200n8 console=ttyARC0,115200n8";
		};
		@@ -26,8 +34,8 @@
		#address-cells = <1>;
		#size-cells = <1>;

		/* child and parent address space 1:1 mapped */
		ranges;
		/* only perip space at end of low mem accessible */
		ranges = <0x80000000 0x0 0x80000000 0x80000000>;

		core_intc: core-interrupt-controller {
		compatible = "snps,archs-intc";

arch/arc/mm/init.c

+64 −6

Original line number	Diff line number	Diff line
		@@ -15,6 +15,7 @@
		#endif
		#include <linux/swap.h>
		#include <linux/module.h>
		#include <linux/highmem.h>
		#include <asm/page.h>
		#include <asm/pgalloc.h>
		#include <asm/sections.h>
		@@ -27,6 +28,12 @@ EXPORT_SYMBOL(empty_zero_page);
		static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE;
		static unsigned long low_mem_sz;

		#ifdef CONFIG_HIGHMEM
		static unsigned long min_high_pfn;
		static u64 high_mem_start;
		static u64 high_mem_sz;
		#endif

		/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
		static int __init setup_mem_sz(char *str)
		{
		@@ -41,10 +48,22 @@ early_param("mem", setup_mem_sz);

		void __init early_init_dt_add_memory_arch(u64 base, u64 size)
		{
		low_mem_sz = size;
		int in_use = 0;

		if (!low_mem_sz) {
		BUG_ON(base != low_mem_start);
		low_mem_sz = size;
		in_use = 1;
		} else {
		#ifdef CONFIG_HIGHMEM
		high_mem_start = base;
		high_mem_sz = size;
		in_use = 1;
		#endif
		}

		pr_info("Memory @ %llx of %ldM\n", base, TO_MB(size));
		pr_info("Memory @ %llx [%lldM] %s\n",
		base, TO_MB(size), !in_use ? "Not used":"");
		}

		#ifdef CONFIG_BLK_DEV_INITRD
		@@ -74,6 +93,7 @@ early_param("initrd", early_initrd);
		void __init setup_arch_memory(void)
		{
		unsigned long zones_size[MAX_NR_ZONES];
		unsigned long zones_holes[MAX_NR_ZONES];

		init_mm.start_code = (unsigned long)_text;
		init_mm.end_code = (unsigned long)_etext;
		@@ -86,9 +106,26 @@ void __init setup_arch_memory(void)
		/* Last usable page of low mem */
		max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz);

		max_mapnr = max_low_pfn - min_low_pfn;
		#ifdef CONFIG_HIGHMEM
		min_high_pfn = PFN_DOWN(high_mem_start);
		max_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
		#endif

		max_mapnr = max_pfn - min_low_pfn;

		/------------- bootmem allocator setup -----------------------/

		/*
		* seed the bootmem allocator after any DT memory node parsing or
		* "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz
		*
		* Only low mem is added, otherwise we have crashes when allocating
		* mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of
		* avail memory, ending in highmem with a > 32-bit address. However
		* it then tries to memset it with a truncaed 32-bit handle, causing
		* the crash
		*/

		memblock_add(low_mem_start, low_mem_sz);
		memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);

		@@ -101,7 +138,17 @@ void __init setup_arch_memory(void)

		/----------------- node/zones setup --------------------------/
		memset(zones_size, 0, sizeof(zones_size));
		memset(zones_holes, 0, sizeof(zones_holes));

		zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
		zones_holes[ZONE_NORMAL] = 0;

		#ifdef CONFIG_HIGHMEM
		zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;

		/* This handles the peripheral address space hole */
		zones_holes[ZONE_HIGHMEM] = min_high_pfn - max_low_pfn;
		#endif

		/*
		* We can't use the helper free_area_init(zones[]) because it uses
		@@ -112,9 +159,12 @@ void __init setup_arch_memory(void)
		free_area_init_node(0, /* node-id */
		zones_size, /* num pages per zone */
		min_low_pfn, /* first pfn of node */
		NULL); /* NO holes */
		zones_holes); /* holes */

		high_memory = (void *)end_mem;
		#ifdef CONFIG_HIGHMEM
		high_memory = (void *)(min_high_pfn << PAGE_SHIFT);
		kmap_init();
		#endif
		}

		/*
		@@ -125,6 +175,14 @@ void __init setup_arch_memory(void)
		*/
		void __init mem_init(void)
		{
		#ifdef CONFIG_HIGHMEM
		unsigned long tmp;

		reset_all_zones_managed_pages();
		for (tmp = min_high_pfn; tmp < max_pfn; tmp++)
		free_highmem_page(pfn_to_page(tmp));
		#endif

		free_all_bootmem();
		mem_init_print_info(NULL);
		}