[MIPS] setup.c: use early_param() for early command line parsing

There's no point to rewrite some logic to parse command line
to pass initrd parameters or to declare a user memory area.
We could use instead parse_early_param() that does the same
thing.

Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 804b93d..fdbb508 100644 (file)
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -135,138 +135,54 @@ static void __init print_memory_map(void)
        }
 }
 
-static void __init parse_cmdline_early(void)
-{
-       char c = ' ', *to = command_line, *from = saved_command_line;
-       unsigned long start_at, mem_size;
-       int len = 0;
-       int usermem = 0;
-
-       printk("Determined physical RAM map:\n");
-       print_memory_map();
-
-       for (;;) {
-               /*
-                * "mem=XXX[kKmM]" defines a memory region from
-                * 0 to <XXX>, overriding the determined size.
-                * "mem=XXX[KkmM]@YYY[KkmM]" defines a memory region from
-                * <YYY> to <YYY>+<XXX>, overriding the determined size.
-                */
-               if (c == ' ' && !memcmp(from, "mem=", 4)) {
-                       if (to != command_line)
-                               to--;
-                       /*
-                        * If a user specifies memory size, we
-                        * blow away any automatically generated
-                        * size.
-                        */
-                       if (usermem == 0) {
-                               boot_mem_map.nr_map = 0;
-                               usermem = 1;
-                       }
-                       mem_size = memparse(from + 4, &from);
-                       if (*from == '@')
-                               start_at = memparse(from + 1, &from);
-                       else
-                               start_at = 0;
-                       add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
-               }
-               c = *(from++);
-               if (!c)
-                       break;
-               if (CL_SIZE <= ++len)
-                       break;
-               *(to++) = c;
-       }
-       *to = '\0';
-
-       if (usermem) {
-               printk("User-defined physical RAM map:\n");
-               print_memory_map();
-       }
-}
-
 /*
  * Manage initrd
  */
 #ifdef CONFIG_BLK_DEV_INITRD
 
-static int __init parse_rd_cmdline(unsigned long *rd_start, unsigned long *rd_end)
+static int __init rd_start_early(char *p)
 {
-       /*
-        * "rd_start=0xNNNNNNNN" defines the memory address of an initrd
-        * "rd_size=0xNN" it's size
-        */
-       unsigned long start = 0;
-       unsigned long size = 0;
-       unsigned long end;
-       char cmd_line[CL_SIZE];
-       char *start_str;
-       char *size_str;
-       char *tmp;
-
-       strcpy(cmd_line, command_line);
-       *command_line = 0;
-       tmp = cmd_line;
-       /* Ignore "rd_start=" strings in other parameters. */
-       start_str = strstr(cmd_line, "rd_start=");
-       if (start_str && start_str != cmd_line && *(start_str - 1) != ' ')
-               start_str = strstr(start_str, " rd_start=");
-       while (start_str) {
-               if (start_str != cmd_line)
-                       strncat(command_line, tmp, start_str - tmp);
-               start = memparse(start_str + 9, &start_str);
-               tmp = start_str + 1;
-               start_str = strstr(start_str, " rd_start=");
-       }
-       if (*tmp)
-               strcat(command_line, tmp);
-
-       strcpy(cmd_line, command_line);
-       *command_line = 0;
-       tmp = cmd_line;
-       /* Ignore "rd_size" strings in other parameters. */
-       size_str = strstr(cmd_line, "rd_size=");
-       if (size_str && size_str != cmd_line && *(size_str - 1) != ' ')
-               size_str = strstr(size_str, " rd_size=");
-       while (size_str) {
-               if (size_str != cmd_line)
-                       strncat(command_line, tmp, size_str - tmp);
-               size = memparse(size_str + 8, &size_str);
-               tmp = size_str + 1;
-               size_str = strstr(size_str, " rd_size=");
-       }
-       if (*tmp)
-               strcat(command_line, tmp);
+       unsigned long start = memparse(p, &p);
 
 #ifdef CONFIG_64BIT
        /* HACK: Guess if the sign extension was forgotten */
        if (start > 0x0000000080000000 && start < 0x00000000ffffffff)
                start |= 0xffffffff00000000UL;
 #endif
+       initrd_start = start;
+       initrd_end += start;
+
+       return 0;
+}
+early_param("rd_start", rd_start_early);
+
+static int __init rd_size_early(char *p)
+{
+       initrd_end += memparse(p, &p);
 
-       end = start + size;
-       if (start && end) {
-               *rd_start = start;
-               *rd_end = end;
-               return 1;
-       }
        return 0;
 }
+early_param("rd_size", rd_size_early);
 
 static unsigned long __init init_initrd(void)
 {
-       unsigned long tmp, end;
+       unsigned long tmp, end, size;
        u32 *initrd_header;
 
        ROOT_DEV = Root_RAM0;
 
-       if (parse_rd_cmdline(&initrd_start, &initrd_end))
-               return initrd_end;
        /*
-        * Board specific code should have set up initrd_start
-        * and initrd_end...
+        * Board specific code or command line parser should have
+        * already set up initrd_start and initrd_end. In these cases
+        * perfom sanity checks and use them if all looks good.
         */
+       size = initrd_end - initrd_start;
+       if (initrd_end == 0 || size == 0) {
+               initrd_start = 0;
+               initrd_end = 0;
+       } else
+               return initrd_end;
+
        end = (unsigned long)&_end;
        tmp = PAGE_ALIGN(end) - sizeof(u32) * 2;
        if (tmp < end)
@@ -436,8 +352,6 @@ static void __init bootmem_init(void)
  *
  *  o plat_mem_setup() detects the memory configuration and will record detected
  *    memory areas using add_memory_region.
- *  o parse_cmdline_early() parses the command line for mem= options which,
- *    iff detected, will override the results of the automatic detection.
  *
  * At this stage the memory configuration of the system is known to the
  * kernel but generic memory managment system is still entirely uninitialized.
@@ -455,19 +369,53 @@ static void __init bootmem_init(void)
  * initialization hook for anything else was introduced.
  */
 
-extern void plat_mem_setup(void);
+static int usermem __initdata = 0;
+
+static int __init early_parse_mem(char *p)
+{
+       unsigned long start, size;
+
+       /*
+        * If a user specifies memory size, we
+        * blow away any automatically generated
+        * size.
+        */
+       if (usermem == 0) {
+               boot_mem_map.nr_map = 0;
+               usermem = 1;
+       }
+       start = 0;
+       size = memparse(p, &p);
+       if (*p == '@')
+               start = memparse(p + 1, &p);
+
+       add_memory_region(start, size, BOOT_MEM_RAM);
+       return 0;
+}
+early_param("mem", early_parse_mem);
 
 static void __init arch_mem_init(char **cmdline_p)
 {
+       extern void plat_mem_setup(void);
+
        /* call board setup routine */
        plat_mem_setup();
 
+       printk("Determined physical RAM map:\n");
+       print_memory_map();
+
        strlcpy(command_line, arcs_cmdline, sizeof(command_line));
        strlcpy(saved_command_line, command_line, COMMAND_LINE_SIZE);
 
        *cmdline_p = command_line;
 
-       parse_cmdline_early();
+       parse_early_param();
+
+       if (usermem) {
+               printk("User-defined physical RAM map:\n");
+               print_memory_map();
+       }
+
        bootmem_init();
        sparse_init();
        paging_init();