MIPS: Loongson: Cleanup of the environment variables

Changes:

	o Move bus_clock into prom_init_env()
	o Initialize the cpu_clock_freq to the default values for the
	correspoding processor revisions if no such environment variable
	passed by BIOS/Bootloader.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: yanh@lemote.com
Cc: huhb@lemote.com
Cc: zhangfx@lemote.com
Patchwork: http://patchwork.linux-mips.org/patch/826/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

2 files changed, 22 insertions, 5 deletions

diff --git a/arch/mips/include/asm/mach-loongson/loongson.h b/arch/mips/include/asm/mach-loongson/loongson.h
index ee8bc8376972..a6eac0f93799 100644
--- a/arch/mips/include/asm/mach-loongson/loongson.h
+++ b/arch/mips/include/asm/mach-loongson/loongson.h
@@ -23,7 +23,7 @@ extern void mach_prepare_reboot(void);
 extern void mach_prepare_shutdown(void);
 
 /* environment arguments from bootloader */
-extern unsigned long bus_clock, cpu_clock_freq;
+extern unsigned long cpu_clock_freq;
 extern unsigned long memsize, highmemsize;
 
 /* loongson-specific command line, env and memory initialization */
diff --git a/arch/mips/loongson/common/env.c b/arch/mips/loongson/common/env.c
index 196d947d929a..8c01df5758a9 100644
--- a/arch/mips/loongson/common/env.c
+++ b/arch/mips/loongson/common/env.c
@@ -23,13 +23,10 @@
 
 #include <loongson.h>
 
-unsigned long bus_clock, cpu_clock_freq;
+unsigned long cpu_clock_freq;
 EXPORT_SYMBOL(cpu_clock_freq);
 unsigned long memsize, highmemsize;
 
-/* pmon passes arguments in 32bit pointers */
-int *_prom_envp;
-
 #define parse_even_earlier(res, option, p)                              \
 do {                                                                    \
         if (strncmp(option, (char *)p, strlen(option)) == 0)            \
@@ -39,6 +36,10 @@ do {									\
 
 void __init prom_init_env(void)
 {
+        /* pmon passes arguments in 32bit pointers */
+        int *_prom_envp;
+        unsigned long bus_clock;
+        unsigned int processor_id;
         long l;
 
         /* firmware arguments are initialized in head.S */
@@ -55,6 +56,22 @@ void __init prom_init_env(void)
         }
         if (memsize == 0)
                 memsize = 256;
+        if (bus_clock == 0)
+                bus_clock = 66000000;
+        if (cpu_clock_freq == 0) {
+                processor_id = (&current_cpu_data)->processor_id;
+                switch (processor_id & PRID_REV_MASK) {
+                case PRID_REV_LOONGSON2E:
+                        cpu_clock_freq = 533080000;
+                        break;
+                case PRID_REV_LOONGSON2F:
+                        cpu_clock_freq = 797000000;
+                        break;
+                default:
+                        cpu_clock_freq = 100000000;
+                        break;
+                }
+        }
 
         pr_info("busclock=%ld, cpuclock=%ld, memsize=%ld, highmemsize=%ld\n",
                 bus_clock, cpu_clock_freq, memsize, highmemsize);