microblaze_mmu_v2: MMU initialization (4dc60832) · Commits · e / devices / android_kernel_oneplus_sm7250

arch/microblaze/mm/init.c

+154 −4

Original line number	Diff line number	Diff line
		@@ -23,18 +23,26 @@
		#include <asm/sections.h>
		#include <asm/tlb.h>

		#ifndef CONFIG_MMU
		unsigned int __page_offset;
		EXPORT_SYMBOL(__page_offset);

		#else
		DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

		int mem_init_done;
		static int init_bootmem_done;
		#endif /* CONFIG_MMU */

		char *klimit = _end;

		/*
		* Initialize the bootmem system and give it all the memory we
		* have available.
		*/
		unsigned int memory_start;
		unsigned int memory_end; /* due to mm/nommu.c */
		unsigned int memory_size;
		unsigned long memory_start;
		unsigned long memory_end; /* due to mm/nommu.c */
		unsigned long memory_size;

		/*
		* paging_init() sets up the page tables - in fact we've already done this.
		@@ -59,6 +67,7 @@ void __init setup_memory(void)
		{
		int i;
		unsigned long map_size;
		#ifndef CONFIG_MMU
		u32 kernel_align_start, kernel_align_size;

		/* Find main memory where is the kernel */
		@@ -91,6 +100,7 @@ void __init setup_memory(void)
		__func__, kernel_align_start, kernel_align_start
		+ kernel_align_size, kernel_align_size);

		#endif
		/*
		* Kernel:
		* start: base phys address of kernel - page align
		@@ -119,9 +129,13 @@ void __init setup_memory(void)
		* for 4GB of memory, using 4kB pages), plus 1 page
		* (in case the address isn't page-aligned).
		*/
		#ifndef CONFIG_MMU
		map_size = init_bootmem_node(NODE_DATA(0), PFN_UP(TOPHYS((u32)_end)),
		min_low_pfn, max_low_pfn);

		#else
		map_size = init_bootmem_node(&contig_page_data,
		PFN_UP(TOPHYS((u32)_end)), min_low_pfn, max_low_pfn);
		#endif
		lmb_reserve(PFN_UP(TOPHYS((u32)_end)) << PAGE_SHIFT, map_size);

		/* free bootmem is whole main memory */
		@@ -135,6 +149,9 @@ void __init setup_memory(void)
		reserve_bootmem(lmb.reserved.region[i].base,
		lmb_size_bytes(&lmb.reserved, i) - 1, BOOTMEM_DEFAULT);
		}
		#ifdef CONFIG_MMU
		init_bootmem_done = 1;
		#endif
		paging_init();
		}

		@@ -189,8 +206,12 @@ void __init mem_init(void)
		printk(KERN_INFO "Memory: %luk/%luk available\n",
		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
		num_physpages << (PAGE_SHIFT-10));
		#ifdef CONFIG_MMU
		mem_init_done = 1;
		#endif
		}

		#ifndef CONFIG_MMU
		/* Check against bounds of physical memory */
		int ___range_ok(unsigned long addr, unsigned long size)
		{
		@@ -198,3 +219,132 @@ int ___range_ok(unsigned long addr, unsigned long size)
		((addr + size) > memory_end));
		}
		EXPORT_SYMBOL(___range_ok);

		#else
		int page_is_ram(unsigned long pfn)
		{
		return pfn < max_low_pfn;
		}

		/*
		* Check for command-line options that affect what MMU_init will do.
		*/
		static void mm_cmdline_setup(void)
		{
		unsigned long maxmem = 0;
		char *p = cmd_line;

		/* Look for mem= option on command line */
		p = strstr(cmd_line, "mem=");
		if (p) {
		p += 4;
		maxmem = memparse(p, &p);
		if (maxmem && memory_size > maxmem) {
		memory_size = maxmem;
		memory_end = memory_start + memory_size;
		lmb.memory.region[0].size = memory_size;
		}
		}
		}

		/*
		* MMU_init_hw does the chip-specific initialization of the MMU hardware.
		*/
		static void __init mmu_init_hw(void)
		{
		/*
		* The Zone Protection Register (ZPR) defines how protection will
		* be applied to every page which is a member of a given zone. At
		* present, we utilize only two of the zones.
		* The zone index bits (of ZSEL) in the PTE are used for software
		* indicators, except the LSB. For user access, zone 1 is used,
		* for kernel access, zone 0 is used. We set all but zone 1
		* to zero, allowing only kernel access as indicated in the PTE.
		* For zone 1, we set a 01 binary (a value of 10 will not work)
		* to allow user access as indicated in the PTE. This also allows
		* kernel access as indicated in the PTE.
		*/
		__asm__ __volatile__ ("ori r11, r0, 0x10000000;" \
		"mts rzpr, r11;"
		: : : "r11");
		}

		/*
		* MMU_init sets up the basic memory mappings for the kernel,
		* including both RAM and possibly some I/O regions,
		* and sets up the page tables and the MMU hardware ready to go.
		*/

		/* called from head.S */
		asmlinkage void __init mmu_init(void)
		{
		unsigned int kstart, ksize;

		if (!lmb.reserved.cnt) {
		printk(KERN_EMERG "Error memory count\n");
		machine_restart(NULL);
		}

		if ((u32) lmb.memory.region[0].size < 0x1000000) {
		printk(KERN_EMERG "Memory must be greater than 16MB\n");
		machine_restart(NULL);
		}
		/* Find main memory where the kernel is */
		memory_start = (u32) lmb.memory.region[0].base;
		memory_end = (u32) lmb.memory.region[0].base +
		(u32) lmb.memory.region[0].size;
		memory_size = memory_end - memory_start;

		mm_cmdline_setup(); /* FIXME parse args from command line - not used */

		/*
		* Map out the kernel text/data/bss from the available physical
		* memory.
		*/
		kstart = __pa(CONFIG_KERNEL_START); /* kernel start */
		/* kernel size */
		ksize = PAGE_ALIGN(((u32)_end - (u32)CONFIG_KERNEL_START));
		lmb_reserve(kstart, ksize);

		#if defined(CONFIG_BLK_DEV_INITRD)
		/* Remove the init RAM disk from the available memory. */
		/* if (initrd_start) {
		mem_pieces_remove(&phys_avail, __pa(initrd_start),
		initrd_end - initrd_start, 1);
		}*/
		#endif /* CONFIG_BLK_DEV_INITRD */

		/* Initialize the MMU hardware */
		mmu_init_hw();

		/* Map in all of RAM starting at CONFIG_KERNEL_START */
		mapin_ram();

		#ifdef HIGHMEM_START_BOOL
		ioremap_base = HIGHMEM_START;
		#else
		ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
		#endif /* CONFIG_HIGHMEM */
		ioremap_bot = ioremap_base;

		/* Initialize the context management stuff */
		mmu_context_init();
		}

		/* This is only called until mem_init is done. */
		void __init *early_get_page(void)
		{
		void *p;
		if (init_bootmem_done) {
		p = alloc_bootmem_pages(PAGE_SIZE);
		} else {
		/*
		* Mem start + 32MB -> here is limit
		* because of mem mapping from head.S
		*/
		p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE,
		memory_start + 0x2000000));
		}
		return p;
		}
		#endif /* CONFIG_MMU */