arch/arc/lib/bootm.c

   1 /*
   2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8
   9 DECLARE_GLOBAL_DATA_PTR;
  10
  11 static ulong get_sp(void)
  12 {
  13         ulong ret;
  14
  15         asm("mov %0, sp" : "=r"(ret) : );
  16         return ret;
  17 }
  18
  19 void arch_lmb_reserve(struct lmb *lmb)
  20 {
  21         ulong sp;
  22
  23         /*
  24          * Booting a (Linux) kernel image
  25          *
  26          * Allocate space for command line and board info - the
  27          * address should be as high as possible within the reach of
  28          * the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
  29          * memory, which means far enough below the current stack
  30          * pointer.
  31          */
  32         sp = get_sp();
  33         debug("## Current stack ends at 0x%08lx ", sp);
  34
  35         /* adjust sp by 4K to be safe */
  36         sp -= 4096;
  37         lmb_reserve(lmb, sp, (CONFIG_SYS_SDRAM_BASE + gd->ram_size - sp));
  38 }
  39
  40 static int cleanup_before_linux(void)
  41 {
  42         disable_interrupts();
  43         flush_dcache_all();
  44         invalidate_icache_all();
  45
  46         return 0;
  47 }
  48
  49 /* Subcommand: PREP */
  50 static void boot_prep_linux(bootm_headers_t *images)
  51 {
  52         if (image_setup_linux(images))
  53                 hang();
  54 }
  55
  56 /* Subcommand: GO */
  57 static void boot_jump_linux(bootm_headers_t *images, int flag)
  58 {
  59         void (*kernel_entry)(int zero, int arch, uint params);
  60         unsigned int r0, r2;
  61         int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
  62
  63         kernel_entry = (void (*)(int, int, uint))images->ep;
  64
  65         debug("## Transferring control to Linux (at address %08lx)...\n",
  66               (ulong) kernel_entry);
  67         bootstage_mark(BOOTSTAGE_ID_RUN_OS);
  68
  69         printf("\nStarting kernel ...%s\n\n", fake ?
  70                "(fake run for tracing)" : "");
  71         bootstage_mark_name(BOOTSTAGE_ID_BOOTM_HANDOFF, "start_kernel");
  72
  73         cleanup_before_linux();
  74
  75         if (IMAGE_ENABLE_OF_LIBFDT && images->ft_len) {
  76                 r0 = 2;
  77                 r2 = (unsigned int)images->ft_addr;
  78         } else {
  79                 r0 = 1;
  80                 r2 = (unsigned int)getenv("bootargs");
  81         }
  82
  83         if (!fake)
  84                 kernel_entry(r0, 0, r2);
  85 }
  86
  87 int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
  88 {
  89         /* No need for those on ARC */
  90         if ((flag & BOOTM_STATE_OS_BD_T) || (flag & BOOTM_STATE_OS_CMDLINE))
  91                 return -1;
  92
  93         if (flag & BOOTM_STATE_OS_PREP) {
  94                 boot_prep_linux(images);
  95                 return 0;
  96         }
  97
  98         if (flag & (BOOTM_STATE_OS_GO | BOOTM_STATE_OS_FAKE_GO)) {
  99                 boot_jump_linux(images, flag);
 100                 return 0;
 101         }
 102
 103         boot_prep_linux(images);
 104         boot_jump_linux(images, flag);
 105         return 0;
 106 }