target/linux/s3c24xx/patches-2.6.24/1070-kexec-atags.patch.patch

   1 From 68bcfea9ab5d8947f711a97dcc291cb9da47c7da Mon Sep 17 00:00:00 2001
   2 From: mokopatches <mokopatches@openmoko.org>
   3 Date: Sun, 13 Apr 2008 07:23:59 +0100
   4 Subject: [PATCH] kexec-atags.patch
   5  Leapfrogged from upstream (ARM Linux)
   6  http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=4736/1
   7
   8 ---
   9  arch/arm/Kconfig                  |    7 +++
  10  arch/arm/kernel/Makefile          |    1 +
  11  arch/arm/kernel/atags.c           |   86 +++++++++++++++++++++++++++++++++++++
  12  arch/arm/kernel/atags.h           |    5 ++
  13  arch/arm/kernel/machine_kexec.c   |    2 +
  14  arch/arm/kernel/relocate_kernel.S |   30 ++-----------
  15  arch/arm/kernel/setup.c           |   32 +-------------
  16  include/asm-arm/kexec.h           |    3 +
  17  8 files changed, 110 insertions(+), 56 deletions(-)
  18  create mode 100644 arch/arm/kernel/atags.c
  19  create mode 100644 arch/arm/kernel/atags.h
  20
  21 diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
  22 index 23e3d6b..ef7b9ff 100644
  23 --- a/arch/arm/Kconfig
  24 +++ b/arch/arm/Kconfig
  25 @@ -865,6 +865,13 @@ config KEXEC
  26           initially work for you.  It may help to enable device hotplugging
  27           support.
  28
  29 +config ATAGS_PROC
  30 +       bool "Export atags in procfs"
  31 +       default n
  32 +       help
  33 +         Should the atags used to boot the kernel be exported in an "atags"
  34 +         file in procfs. Useful with kexec.
  35 +
  36  endmenu
  37
  38  if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP || ARCH_IMX )
  39 diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
  40 index 593b565..5cf694c 100644
  41 --- a/arch/arm/kernel/Makefile
  42 +++ b/arch/arm/kernel/Makefile
  43 @@ -19,6 +19,7 @@ obj-$(CONFIG_ISA_DMA)         += dma-isa.o
  44  obj-$(CONFIG_PCI)              += bios32.o isa.o
  45  obj-$(CONFIG_SMP)              += smp.o
  46  obj-$(CONFIG_KEXEC)            += machine_kexec.o relocate_kernel.o
  47 +obj-$(CONFIG_ATAGS_PROC)       += atags.o
  48  obj-$(CONFIG_OABI_COMPAT)      += sys_oabi-compat.o
  49
  50  obj-$(CONFIG_CRUNCH)           += crunch.o crunch-bits.o
  51 diff --git a/arch/arm/kernel/atags.c b/arch/arm/kernel/atags.c
  52 new file mode 100644
  53 index 0000000..e2e934c
  54 --- /dev/null
  55 +++ b/arch/arm/kernel/atags.c
  56 @@ -0,0 +1,86 @@
  57 +#include <linux/slab.h>
  58 +#include <linux/kexec.h>
  59 +#include <linux/proc_fs.h>
  60 +#include <asm/setup.h>
  61 +#include <asm/types.h>
  62 +#include <asm/page.h>
  63 +
  64 +struct buffer {
  65 +       size_t size;
  66 +       char *data;
  67 +};
  68 +static struct buffer tags_buffer;
  69 +
  70 +static int
  71 +read_buffer(char* page, char** start, off_t off, int count,
  72 +       int* eof, void* data)
  73 +{
  74 +       struct buffer *buffer = (struct buffer *)data;
  75 +
  76 +       if (off >= buffer->size) {
  77 +               *eof = 1;
  78 +               return 0;
  79 +       }
  80 +
  81 +       count = min((int) (buffer->size - off), count);
  82 +
  83 +       memcpy(page, &buffer->data[off], count);
  84 +
  85 +       return count;
  86 +}
  87 +
  88 +
  89 +static int
  90 +create_proc_entries(void)
  91 +{
  92 +       struct proc_dir_entry* tags_entry;
  93 +
  94 +       tags_entry = create_proc_read_entry("atags", 0400, &proc_root, read_buffer, &tags_buffer);
  95 +       if (!tags_entry)
  96 +               return -ENOMEM;
  97 +
  98 +       return 0;
  99 +}
 100 +
 101 +
 102 +static char __initdata atags_copy_buf[KEXEC_BOOT_PARAMS_SIZE];
 103 +static char __initdata *atags_copy;
 104 +
 105 +void __init save_atags(const struct tag *tags)
 106 +{
 107 +       atags_copy = atags_copy_buf;
 108 +       memcpy(atags_copy, tags, KEXEC_BOOT_PARAMS_SIZE);
 109 +}
 110 +
 111 +
 112 +static int __init init_atags_procfs(void)
 113 +{
 114 +       struct tag *tag;
 115 +       int error;
 116 +
 117 +       if (!atags_copy) {
 118 +               printk(KERN_WARNING "Exporting ATAGs: No saved tags found\n");
 119 +               return -EIO;
 120 +       }
 121 +
 122 +       for (tag = (struct tag *) atags_copy; tag->hdr.size; tag = tag_next(tag))
 123 +               ;
 124 +
 125 +       tags_buffer.size = ((char *) tag - atags_copy) + sizeof(tag->hdr);
 126 +       tags_buffer.data = kmalloc(tags_buffer.size, GFP_KERNEL);
 127 +       if (tags_buffer.data == NULL)
 128 +               return -ENOMEM;
 129 +       memcpy(tags_buffer.data, atags_copy, tags_buffer.size);
 130 +
 131 +       error = create_proc_entries();
 132 +       if (error) {
 133 +               printk(KERN_ERR "Exporting ATAGs: not enough memory\n");
 134 +               kfree(tags_buffer.data);
 135 +               tags_buffer.size = 0;
 136 +               tags_buffer.data = NULL;
 137 +       }
 138 +
 139 +       return error;
 140 +}
 141 +
 142 +arch_initcall(init_atags_procfs);
 143 diff --git a/arch/arm/kernel/atags.h b/arch/arm/kernel/atags.h
 144 new file mode 100644
 145 index 0000000..e5f028d
 146 --- /dev/null
 147 +++ b/arch/arm/kernel/atags.h
 148 @@ -0,0 +1,5 @@
 149 +#ifdef CONFIG_ATAGS_PROC
 150 +extern void save_atags(struct tag *tags);
 151 +#else
 152 +static inline void save_atags(struct tag *tags) { }
 153 +#endif
 154 diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
 155 index 863c664..db8f54a 100644
 156 --- a/arch/arm/kernel/machine_kexec.c
 157 +++ b/arch/arm/kernel/machine_kexec.c
 158 @@ -21,6 +21,7 @@ extern void setup_mm_for_reboot(char mode);
 159  extern unsigned long kexec_start_address;
 160  extern unsigned long kexec_indirection_page;
 161  extern unsigned long kexec_mach_type;
 162 +extern unsigned long kexec_boot_atags;
 163
 164  /*
 165   * Provide a dummy crash_notes definition while crash dump arrives to arm.
 166 @@ -62,6 +63,7 @@ void machine_kexec(struct kimage *image)
 167         kexec_start_address = image->start;
 168         kexec_indirection_page = page_list;
 169         kexec_mach_type = machine_arch_type;
 170 +       kexec_boot_atags = image->start - KEXEC_ARM_ZIMAGE_OFFSET + KEXEC_ARM_ATAGS_OFFSET;
 171
 172         /* copy our kernel relocation code to the control code page */
 173         memcpy(reboot_code_buffer,
 174 diff --git a/arch/arm/kernel/relocate_kernel.S b/arch/arm/kernel/relocate_kernel.S
 175 index 062c111..61930eb 100644
 176 --- a/arch/arm/kernel/relocate_kernel.S
 177 +++ b/arch/arm/kernel/relocate_kernel.S
 178 @@ -7,23 +7,6 @@
 179         .globl relocate_new_kernel
 180  relocate_new_kernel:
 181
 182 -       /* Move boot params back to where the kernel expects them */
 183 -
 184 -       ldr     r0,kexec_boot_params_address
 185 -       teq     r0,#0
 186 -       beq     8f
 187 -
 188 -       ldr     r1,kexec_boot_params_copy
 189 -       mov     r6,#KEXEC_BOOT_PARAMS_SIZE/4
 190 -7:
 191 -       ldr     r5,[r1],#4
 192 -       str     r5,[r0],#4
 193 -       subs    r6,r6,#1
 194 -       bne     7b
 195 -
 196 -8:
 197 -       /* Boot params moved, now go on with the kernel */
 198 -
 199         ldr     r0,kexec_indirection_page
 200         ldr     r1,kexec_start_address
 201
 202 @@ -67,7 +50,7 @@ relocate_new_kernel:
 203         mov lr,r1
 204         mov r0,#0
 205         ldr r1,kexec_mach_type
 206 -       ldr r2,kexec_boot_params_address
 207 +       ldr r2,kexec_boot_atags
 208         mov pc,lr
 209
 210         .globl kexec_start_address
 211 @@ -82,14 +65,9 @@ kexec_indirection_page:
 212  kexec_mach_type:
 213         .long   0x0
 214
 215 -       /* phy addr where new kernel will expect to find boot params */
 216 -       .globl kexec_boot_params_address
 217 -kexec_boot_params_address:
 218 -       .long   0x0
 219 -
 220 -       /* phy addr where old kernel put a copy of orig boot params */
 221 -       .globl kexec_boot_params_copy
 222 -kexec_boot_params_copy:
 223 +       /* phy addr of the atags for the new kernel */
 224 +       .globl kexec_boot_atags
 225 +kexec_boot_atags:
 226         .long   0x0
 227
 228  relocate_new_kernel_end:
 229 diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
 230 index bf56eb3..ae3712d 100644
 231 --- a/arch/arm/kernel/setup.c
 232 +++ b/arch/arm/kernel/setup.c
 233 @@ -24,7 +24,6 @@
 234  #include <linux/interrupt.h>
 235  #include <linux/smp.h>
 236  #include <linux/fs.h>
 237 -#include <linux/kexec.h>
 238
 239  #include <asm/cpu.h>
 240  #include <asm/elf.h>
 241 @@ -39,6 +38,7 @@
 242  #include <asm/mach/time.h>
 243
 244  #include "compat.h"
 245 +#include "atags.h"
 246
 247  #ifndef MEM_SIZE
 248  #define MEM_SIZE       (16*1024*1024)
 249 @@ -784,23 +784,6 @@ static int __init customize_machine(void)
 250  }
 251  arch_initcall(customize_machine);
 252
 253 -#ifdef CONFIG_KEXEC
 254 -
 255 -/* Physical addr of where the boot params should be for this machine */
 256 -extern unsigned long kexec_boot_params_address;
 257 -
 258 -/* Physical addr of the buffer into which the boot params are copied */
 259 -extern unsigned long kexec_boot_params_copy;
 260 -
 261 -/* Pointer to the boot params buffer, for manipulation and display */
 262 -unsigned long kexec_boot_params;
 263 -EXPORT_SYMBOL(kexec_boot_params);
 264 -
 265 -/* The buffer itself - make sure it is sized correctly */
 266 -static unsigned long kexec_boot_params_buf[(KEXEC_BOOT_PARAMS_SIZE + 3) / 4];
 267 -
 268 -#endif
 269 -
 270  void __init setup_arch(char **cmdline_p)
 271  {
 272         struct tag *tags = (struct tag *)&init_tags;
 273 @@ -819,18 +802,6 @@ void __init setup_arch(char **cmdline_p)
 274         else if (mdesc->boot_params)
 275                 tags = phys_to_virt(mdesc->boot_params);
 276
 277 -#ifdef CONFIG_KEXEC
 278 -       kexec_boot_params_copy = virt_to_phys(kexec_boot_params_buf);
 279 -       kexec_boot_params = (unsigned long)kexec_boot_params_buf;
 280 -       if (__atags_pointer) {
 281 -               kexec_boot_params_address = __atags_pointer;
 282 -               memcpy((void *)kexec_boot_params, tags, KEXEC_BOOT_PARAMS_SIZE);
 283 -       } else if (mdesc->boot_params) {
 284 -               kexec_boot_params_address = mdesc->boot_params;
 285 -               memcpy((void *)kexec_boot_params, tags, KEXEC_BOOT_PARAMS_SIZE);
 286 -       }
 287 -#endif
 288 -
 289         /*
 290          * If we have the old style parameters, convert them to
 291          * a tag list.
 292 @@ -846,6 +817,7 @@ void __init setup_arch(char **cmdline_p)
 293         if (tags->hdr.tag == ATAG_CORE) {
 294                 if (meminfo.nr_banks != 0)
 295                         squash_mem_tags(tags);
 296 +               save_atags(tags);
 297                 parse_tags(tags);
 298         }
 299
 300 diff --git a/include/asm-arm/kexec.h b/include/asm-arm/kexec.h
 301 index 46dcc4d..1ee17b6 100644
 302 --- a/include/asm-arm/kexec.h
 303 +++ b/include/asm-arm/kexec.h
 304 @@ -16,6 +16,9 @@
 305
 306  #define KEXEC_BOOT_PARAMS_SIZE 1536
 307
 308 +#define KEXEC_ARM_ATAGS_OFFSET  0x1000
 309 +#define KEXEC_ARM_ZIMAGE_OFFSET 0x8000
 310 +
 311  #ifndef __ASSEMBLY__
 312
 313  struct kimage;
 314 --
 315 1.5.6.5
 316