1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #include <linux/console.h> 5 #include <linux/memblock.h> 6 #include <linux/initrd.h> 7 #include <linux/of.h> 8 #include <linux/of_fdt.h> 9 #include <linux/start_kernel.h> 10 #include <linux/dma-map-ops.h> 11 #include <linux/screen_info.h> 12 #include <asm/sections.h> 13 #include <asm/mmu_context.h> 14 #include <asm/pgalloc.h> 15 16 #ifdef CONFIG_DUMMY_CONSOLE 17 struct screen_info screen_info = { 18 .orig_video_lines = 30, 19 .orig_video_cols = 80, 20 .orig_video_mode = 0, 21 .orig_video_ega_bx = 0, 22 .orig_video_isVGA = 1, 23 .orig_video_points = 8 24 }; 25 #endif 26 27 static void __init csky_memblock_init(void) 28 { 29 unsigned long lowmem_size = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET); 30 unsigned long sseg_size = PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET); 31 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 }; 32 signed long size; 33 34 memblock_reserve(__pa(_stext), _end - _stext); 35 36 early_init_fdt_reserve_self(); 37 early_init_fdt_scan_reserved_mem(); 38 39 memblock_dump_all(); 40 41 min_low_pfn = PFN_UP(memblock_start_of_DRAM()); 42 max_low_pfn = max_pfn = PFN_DOWN(memblock_end_of_DRAM()); 43 44 size = max_pfn - min_low_pfn; 45 46 if (size >= lowmem_size) { 47 max_low_pfn = min_low_pfn + lowmem_size; 48 write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE); 49 } else if (size > sseg_size) { 50 max_low_pfn = min_low_pfn + sseg_size; 51 } 52 53 max_zone_pfn[ZONE_NORMAL] = max_low_pfn; 54 55 #ifdef CONFIG_HIGHMEM 56 max_zone_pfn[ZONE_HIGHMEM] = max_pfn; 57 58 highstart_pfn = max_low_pfn; 59 highend_pfn = max_pfn; 60 #endif 61 memblock_set_current_limit(PFN_PHYS(max_low_pfn)); 62 63 dma_contiguous_reserve(0); 64 65 free_area_init(max_zone_pfn); 66 } 67 68 void __init setup_arch(char **cmdline_p) 69 { 70 *cmdline_p = boot_command_line; 71 72 console_verbose(); 73 74 pr_info("Phys. mem: %ldMB\n", 75 (unsigned long) memblock_phys_mem_size()/1024/1024); 76 77 init_mm.start_code = (unsigned long) _stext; 78 init_mm.end_code = (unsigned long) _etext; 79 init_mm.end_data = (unsigned long) _edata; 80 init_mm.brk = (unsigned long) _end; 81 82 parse_early_param(); 83 84 csky_memblock_init(); 85 86 unflatten_and_copy_device_tree(); 87 88 #ifdef CONFIG_SMP 89 setup_smp(); 90 #endif 91 92 sparse_init(); 93 94 fixaddr_init(); 95 96 #ifdef CONFIG_HIGHMEM 97 kmap_init(); 98 #endif 99 } 100 101 unsigned long va_pa_offset; 102 EXPORT_SYMBOL(va_pa_offset); 103 104 asmlinkage __visible void __init csky_start(unsigned int unused, 105 void *dtb_start) 106 { 107 /* Clean up bss section */ 108 memset(__bss_start, 0, __bss_stop - __bss_start); 109 110 va_pa_offset = read_mmu_msa0() & ~(SSEG_SIZE - 1); 111 112 pre_trap_init(); 113 pre_mmu_init(); 114 115 if (dtb_start == NULL) 116 early_init_dt_scan(__dtb_start); 117 else 118 early_init_dt_scan(dtb_start); 119 120 start_kernel(); 121 122 asm volatile("br .\n"); 123 } 124