arm/dt: consolidate atags setup into setup_machine_atags

In preparation for adding device tree support, this patch consolidates
all of the atag-specific setup into a single function.

v5: - drop double printk("Machine; %s\n", ...); call.
    - leave copying boot_command_line in setup_arch() since it isn't
      atags specific.
v4: - adapt to the removal of lookup_machine_type()
    - break out dump of machine_desc table into dump_machine_table()
      because the device tree probe code will use it.
    - Add for_each_machine_desc() macro

Tested-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 40 insertions, 29 deletions

diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 109997e3fe4a..42c2f0cedf1b 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -439,25 +439,12 @@ void cpu_init(void)
             : "r14");
 }
 
-static struct machine_desc * __init setup_machine(unsigned int nr)
+static void __init dump_machine_table(void)
 {
-        extern struct machine_desc __arch_info_begin[], __arch_info_end[];
         struct machine_desc *p;
 
-        /*
-         * locate machine in the list of supported machines.
-         */
-        for (p = __arch_info_begin; p < __arch_info_end; p++)
-                if (nr == p->nr) {
-                        printk("Machine: %s\n", p->name);
-                        return p;
-                }
-
-        early_print("\n"
-                "Error: unrecognized/unsupported machine ID (r1 = 0x%08x).\n\n"
-                "Available machine support:\n\nID (hex)\tNAME\n", nr);
-
-        for (p = __arch_info_begin; p < __arch_info_end; p++)
+        early_print("Available machine support:\n\nID (hex)\tNAME\n");
+        for_each_machine_desc(p)
                 early_print("%08x\t%s\n", p->nr, p->name);
 
         early_print("\nPlease check your kernel config and/or bootloader.\n");
@@ -796,23 +783,29 @@ static void __init squash_mem_tags(struct tag *tag)
                         tag->hdr.tag = ATAG_NONE;
 }
 
-void __init setup_arch(char **cmdline_p)
+static struct machine_desc * __init setup_machine_tags(unsigned int nr)
 {
         struct tag *tags = (struct tag *)&init_tags;
-        struct machine_desc *mdesc;
+        struct machine_desc *mdesc = NULL, *p;
         char *from = default_command_line;
 
         init_tags.mem.start = PHYS_OFFSET;
 
-        unwind_init();
-
-        setup_processor();
-        mdesc = setup_machine(machine_arch_type);
-        machine_desc = mdesc;
-        machine_name = mdesc->name;
+        /*
+         * locate machine in the list of supported machines.
+         */
+        for_each_machine_desc(p)
+                if (nr == p->nr) {
+                        printk("Machine: %s\n", p->name);
+                        mdesc = p;
+                        break;
+                }
 
-        if (mdesc->soft_reboot)
-                reboot_setup("s");
+        if (!mdesc) {
+                early_print("\nError: unrecognized/unsupported machine ID"
+                        " (r1 = 0x%08x).\n\n", nr);
+                dump_machine_table(); /* does not return */
+        }
 
         if (__atags_pointer)
                 tags = phys_to_virt(__atags_pointer);
@@ -857,14 +850,32 @@ void __init setup_arch(char **cmdline_p)
                 parse_tags(tags);
         }
 
+        /* parse_early_param needs a boot_command_line */
+        strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
+
+        return mdesc;
+}
+
+
+void __init setup_arch(char **cmdline_p)
+{
+        struct machine_desc *mdesc;
+
+        unwind_init();
+
+        setup_processor();
+        mdesc = setup_machine_tags(machine_arch_type);
+        machine_desc = mdesc;
+        machine_name = mdesc->name;
+
+        if (mdesc->soft_reboot)
+                reboot_setup("s");
+
         init_mm.start_code = (unsigned long) _text;
         init_mm.end_code   = (unsigned long) _etext;
         init_mm.end_data   = (unsigned long) _edata;
         init_mm.brk        = (unsigned long) _end;
 
-        /* parse_early_param needs a boot_command_line */
-        strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
-
         /* populate cmd_line too for later use, preserving boot_command_line */
         strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
         *cmdline_p = cmd_line;