arch/csky/kernel/setup.c

   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-contiguous.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 zone_size[MAX_NR_ZONES];
  30         signed long size;
  31
  32         memblock_reserve(__pa(_stext), _end - _stext);
  33
  34         early_init_fdt_reserve_self();
  35         early_init_fdt_scan_reserved_mem();
  36
  37         memblock_dump_all();
  38
  39         memset(zone_size, 0, sizeof(zone_size));
  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 <= PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET))
  47                 zone_size[ZONE_NORMAL] = size;
  48         else if (size < PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET)) {
  49                 zone_size[ZONE_NORMAL] =
  50                                 PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET);
  51                 max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
  52         } else {
  53                 zone_size[ZONE_NORMAL] =
  54                                 PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
  55                 max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
  56                 write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE);
  57         }
  58
  59 #ifdef CONFIG_HIGHMEM
  60         zone_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
  61
  62         highstart_pfn = max_low_pfn;
  63         highend_pfn   = max_pfn;
  64 #endif
  65         memblock_set_current_limit(PFN_PHYS(max_low_pfn));
  66
  67         dma_contiguous_reserve(0);
  68
  69         free_area_init_node(0, zone_size, min_low_pfn, NULL);
  70 }
  71
  72 void __init setup_arch(char **cmdline_p)
  73 {
  74         *cmdline_p = boot_command_line;
  75
  76         console_verbose();
  77
  78         pr_info("Phys. mem: %ldMB\n",
  79                 (unsigned long) memblock_phys_mem_size()/1024/1024);
  80
  81         init_mm.start_code = (unsigned long) _stext;
  82         init_mm.end_code = (unsigned long) _etext;
  83         init_mm.end_data = (unsigned long) _edata;
  84         init_mm.brk = (unsigned long) _end;
  85
  86         parse_early_param();
  87
  88         csky_memblock_init();
  89
  90         unflatten_and_copy_device_tree();
  91
  92 #ifdef CONFIG_SMP
  93         setup_smp();
  94 #endif
  95
  96         sparse_init();
  97
  98         fixaddr_init();
  99
 100 #ifdef CONFIG_HIGHMEM
 101         kmap_init();
 102 #endif
 103 }
 104
 105 unsigned long va_pa_offset;
 106 EXPORT_SYMBOL(va_pa_offset);
 107
 108 asmlinkage __visible void __init csky_start(unsigned int unused,
 109                                             void *dtb_start)
 110 {
 111         /* Clean up bss section */
 112         memset(__bss_start, 0, __bss_stop - __bss_start);
 113
 114         va_pa_offset = read_mmu_msa0() & ~(SSEG_SIZE - 1);
 115
 116         pre_trap_init();
 117         pre_mmu_init();
 118
 119         if (dtb_start == NULL)
 120                 early_init_dt_scan(__dtb_start);
 121         else
 122                 early_init_dt_scan(dtb_start);
 123
 124         start_kernel();
 125
 126         asm volatile("br .\n");
 127 }