arch/sparc/lib/bootm.c

   1 /* SPARC code for booting linux 2.6
   2  *
   3  * (C) Copyright 2007
   4  * Daniel Hellstrom, Gaisler Research, daniel@gaisler.com.
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <common.h>
  10 #include <command.h>
  11 #include <asm/byteorder.h>
  12 #include <asm/prom.h>
  13 #include <asm/cache.h>
  14 #include <image.h>
  15
  16 #define PRINT_KERNEL_HEADER
  17
  18 extern image_header_t header;
  19 extern void srmmu_init_cpu(unsigned int entry);
  20 extern void prepare_bootargs(char *bootargs);
  21
  22 /* sparc kernel argument (the ROM vector) */
  23 struct linux_romvec *kernel_arg_promvec;
  24
  25 /* page szie is 4k */
  26 #define PAGE_SIZE 0x1000
  27 #define RAMDISK_IMAGE_START_MASK        0x07FF
  28 #define RAMDISK_PROMPT_FLAG             0x8000
  29 #define RAMDISK_LOAD_FLAG               0x4000
  30 struct __attribute__ ((packed)) {
  31         char traptable[PAGE_SIZE];
  32         char swapper_pg_dir[PAGE_SIZE];
  33         char pg0[PAGE_SIZE];
  34         char pg1[PAGE_SIZE];
  35         char pg2[PAGE_SIZE];
  36         char pg3[PAGE_SIZE];
  37         char empty_bad_page[PAGE_SIZE];
  38         char empty_bad_page_table[PAGE_SIZE];
  39         char empty_zero_page[PAGE_SIZE];
  40         unsigned char hdr[4];   /* ascii "HdrS" */
  41         /* 00.02.06.0b is for Linux kernel 2.6.11 */
  42         unsigned char linuxver_mega_major;
  43         unsigned char linuxver_major;
  44         unsigned char linuxver_minor;
  45         unsigned char linuxver_revision;
  46         /* header version 0x0203 */
  47         unsigned short hdr_ver;
  48         union __attribute__ ((packed)) {
  49                 struct __attribute__ ((packed)) {
  50                         unsigned short root_flags;
  51                         unsigned short root_dev;
  52                         unsigned short ram_flags;
  53                         unsigned int sparc_ramdisk_image;
  54                         unsigned int sparc_ramdisk_size;
  55                         unsigned int reboot_command;
  56                         unsigned int resv[3];
  57                         unsigned int end;
  58                 } ver_0203;
  59         } hdr_input;
  60 } *linux_hdr;
  61
  62 /* temporary initrd image holder */
  63 image_header_t ihdr;
  64
  65 void arch_lmb_reserve(struct lmb *lmb)
  66 {
  67         /* Reserve the space used by PROM and stack. This is done
  68          * to avoid that the RAM image is copied over stack or
  69          * PROM.
  70          */
  71         lmb_reserve(lmb, CONFIG_SYS_RELOC_MONITOR_BASE, CONFIG_SYS_RAM_END);
  72 }
  73
  74 /* boot the linux kernel */
  75 int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t * images)
  76 {
  77         char *bootargs;
  78         ulong rd_len;
  79         void (*kernel) (struct linux_romvec *, void *);
  80         int ret;
  81
  82         /*
  83          * allow the PREP bootm subcommand, it is required for bootm to work
  84          */
  85         if (flag & BOOTM_STATE_OS_PREP)
  86                 return 0;
  87
  88         if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
  89                 return 1;
  90
  91         /* Get virtual address of kernel start */
  92         linux_hdr = (void *)images->os.load;
  93
  94         /* */
  95         kernel = (void (*)(struct linux_romvec *, void *))images->ep;
  96
  97         /* check for a SPARC kernel */
  98         if ((linux_hdr->hdr[0] != 'H') ||
  99             (linux_hdr->hdr[1] != 'd') ||
 100             (linux_hdr->hdr[2] != 'r') || (linux_hdr->hdr[3] != 'S')) {
 101                 puts("Error reading header of SPARC Linux kernel, aborting\n");
 102                 goto error;
 103         }
 104 #ifdef PRINT_KERNEL_HEADER
 105         printf("## Found SPARC Linux kernel %d.%d.%d ...\n",
 106                linux_hdr->linuxver_major,
 107                linux_hdr->linuxver_minor, linux_hdr->linuxver_revision);
 108 #endif
 109
 110         /* set basic boot params in kernel header now that it has been
 111          * extracted and is writeable.
 112          */
 113
 114         ret = image_setup_linux(images);
 115         if (ret) {
 116                 puts("### Failed to relocate RAM disk\n");
 117                 goto error;
 118         }
 119
 120         /* Calc length of RAM disk, if zero no ramdisk available */
 121         rd_len = images->rd_end - images->rd_start;
 122
 123         if (rd_len) {
 124                 /* Update SPARC kernel header so that Linux knows
 125                  * what is going on and where to find RAM disk.
 126                  *
 127                  * Set INITRD Image address relative to RAM Start
 128                  */
 129                 linux_hdr->hdr_input.ver_0203.sparc_ramdisk_image =
 130                         images->initrd_start - CONFIG_SYS_RAM_BASE;
 131                 linux_hdr->hdr_input.ver_0203.sparc_ramdisk_size = rd_len;
 132                 /* Clear READ ONLY flag if set to non-zero */
 133                 linux_hdr->hdr_input.ver_0203.root_flags = 1;
 134                 /* Set root device to: Root_RAM0 */
 135                 linux_hdr->hdr_input.ver_0203.root_dev = 0x100;
 136                 linux_hdr->hdr_input.ver_0203.ram_flags = 0;
 137         } else {
 138                 /* NOT using RAMDISK image, overwriting kernel defaults */
 139                 linux_hdr->hdr_input.ver_0203.sparc_ramdisk_image = 0;
 140                 linux_hdr->hdr_input.ver_0203.sparc_ramdisk_size = 0;
 141                 /* Leave to kernel defaults
 142                    linux_hdr->hdr_input.ver_0203.root_flags = 1;
 143                    linux_hdr->hdr_input.ver_0203.root_dev = 0;
 144                    linux_hdr->hdr_input.ver_0203.ram_flags = 0;
 145                  */
 146         }
 147
 148         /* Copy bootargs from bootargs variable to kernel readable area */
 149         bootargs = getenv("bootargs");
 150         prepare_bootargs(bootargs);
 151
 152         /* turn on mmu & setup context table & page table for process 0 (kernel) */
 153         srmmu_init_cpu((unsigned int)kernel);
 154
 155         /* Enter SPARC Linux kernel
 156          * From now on the only code in u-boot that will be
 157          * executed is the PROM code.
 158          */
 159         kernel(kernel_arg_promvec, (void *)images->ep);
 160
 161         /* It will never come to this... */
 162         while (1) ;
 163
 164       error:
 165         return 1;
 166 }