LXR linux/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
  17struct 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
  27static 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
  68void __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
 101unsigned long va_pa_offset;
 102EXPORT_SYMBOL(va_pa_offset);
 103
 104asmlinkage __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