From 4dc60832f516c4ccfd1e6aa07d92cc0f6d21bacb Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Tue, 26 May 2009 16:30:12 +0200 Subject: microblaze_mmu_v2: MMU initialization Signed-off-by: Michal Simek --- arch/microblaze/mm/init.c | 158 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 154 insertions(+), 4 deletions(-) (limited to 'arch/microblaze/mm') diff --git a/arch/microblaze/mm/init.c b/arch/microblaze/mm/init.c index af789e26a7ce..b5a701cd71e0 100644 --- a/arch/microblaze/mm/init.c +++ b/arch/microblaze/mm/init.c @@ -23,18 +23,26 @@ #include #include +#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 */ -- cgit