[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>

1 files changed, 60 insertions, 112 deletions

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 804b93dc3c5a..fdbb508661c5 100644
--- 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();