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 phys_addr_t __init_memblock memblock_end_of_REG0(void)
  28 {
  29         return (memblock.memory.regions[0].base +
  30                 memblock.memory.regions[0].size);
  31 }
  32
  33 phys_addr_t __init_memblock memblock_start_of_REG1(void)
  34 {
  35         return memblock.memory.regions[1].base;
  36 }
  37
  38 size_t __init_memblock memblock_size_of_REG1(void)
  39 {
  40         return memblock.memory.regions[1].size;
  41 }
  42
  43 static void __init csky_memblock_init(void)
  44 {
  45         unsigned long zone_size[MAX_NR_ZONES];
  46         unsigned long zhole_size[MAX_NR_ZONES];
  47         signed long size;
  48
  49         memblock_reserve(__pa(_stext), _end - _stext);
  50
  51         early_init_fdt_reserve_self();
  52         early_init_fdt_scan_reserved_mem();
  53
  54         memblock_dump_all();
  55
  56         memset(zone_size, 0, sizeof(zone_size));
  57         memset(zhole_size, 0, sizeof(zhole_size));
  58
  59         min_low_pfn = PFN_UP(memblock_start_of_DRAM());
  60         max_pfn     = PFN_DOWN(memblock_end_of_DRAM());
  61
  62         max_low_pfn = PFN_UP(memblock_end_of_REG0());
  63         if (max_low_pfn == 0)
  64                 max_low_pfn = max_pfn;
  65
  66         size = max_pfn - min_low_pfn;
  67
  68         if (memblock.memory.cnt > 1) {
  69                 zone_size[ZONE_NORMAL]  =
  70                         PFN_DOWN(memblock_start_of_REG1()) - min_low_pfn;
  71                 zhole_size[ZONE_NORMAL] =
  72                         PFN_DOWN(memblock_start_of_REG1()) - max_low_pfn;
  73         } else {
  74                 if (size <= PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET))
  75                         zone_size[ZONE_NORMAL] = max_pfn - min_low_pfn;
  76                 else {
  77                         zone_size[ZONE_NORMAL] =
  78                                 PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
  79                         max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
  80                 }
  81         }
  82
  83 #ifdef CONFIG_HIGHMEM
  84         size = 0;
  85         if (memblock.memory.cnt > 1) {
  86                 size = PFN_DOWN(memblock_size_of_REG1());
  87                 highstart_pfn = PFN_DOWN(memblock_start_of_REG1());
  88         } else {
  89                 size = max_pfn - min_low_pfn -
  90                         PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
  91                 highstart_pfn =  min_low_pfn +
  92                         PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
  93         }
  94
  95         if (size > 0)
  96                 zone_size[ZONE_HIGHMEM] = size;
  97
  98         highend_pfn = max_pfn;
  99 #endif
 100         memblock_set_current_limit(PFN_PHYS(max_low_pfn));
 101
 102         dma_contiguous_reserve(0);
 103
 104         free_area_init_node(0, zone_size, min_low_pfn, zhole_size);
 105 }
 106
 107 void __init setup_arch(char **cmdline_p)
 108 {
 109         *cmdline_p = boot_command_line;
 110
 111         console_verbose();
 112
 113         pr_info("Phys. mem: %ldMB\n",
 114                 (unsigned long) memblock_phys_mem_size()/1024/1024);
 115
 116         init_mm.start_code = (unsigned long) _stext;
 117         init_mm.end_code = (unsigned long) _etext;
 118         init_mm.end_data = (unsigned long) _edata;
 119         init_mm.brk = (unsigned long) _end;
 120
 121         parse_early_param();
 122
 123         csky_memblock_init();
 124
 125         unflatten_and_copy_device_tree();
 126
 127 #ifdef CONFIG_SMP
 128         setup_smp();
 129 #endif
 130
 131         sparse_init();
 132
 133         fixaddr_init();
 134
 135 #ifdef CONFIG_HIGHMEM
 136         kmap_init();
 137 #endif
 138 }
 139
 140 unsigned long va_pa_offset;
 141 EXPORT_SYMBOL(va_pa_offset);
 142
 143 asmlinkage __visible void __init csky_start(unsigned int unused,
 144                                             void *dtb_start)
 145 {
 146         /* Clean up bss section */
 147         memset(__bss_start, 0, __bss_stop - __bss_start);
 148
 149         va_pa_offset = read_mmu_msa0() & ~(SSEG_SIZE - 1);
 150
 151         pre_trap_init();
 152         pre_mmu_init();
 153
 154         if (dtb_start == NULL)
 155                 early_init_dt_scan(__dtb_start);
 156         else
 157                 early_init_dt_scan(dtb_start);
 158
 159         start_kernel();
 160
 161         asm volatile("br .\n");
 162 }