MIPS: Alchemy: Simple cpu subtype detector

Extract the alchemy chip variant from c0_prid register.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/14/
Patchwork: http://patchwork.linux-mips.org/patch/707/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/arch/mips/include/asm/mach-au1x00/au1000.h b/arch/mips/include/asm/mach-au1x00/au1000.h
index fceeca883359..2dc87d3b0428 100644
--- a/arch/mips/include/asm/mach-au1x00/au1000.h
+++ b/arch/mips/include/asm/mach-au1x00/au1000.h
@@ -130,6 +130,37 @@ static inline int au1xxx_cpu_needs_config_od(void)
         return 0;
 }
 
+#define ALCHEMY_CPU_UNKNOWN     -1
+#define ALCHEMY_CPU_AU1000      0
+#define ALCHEMY_CPU_AU1500      1
+#define ALCHEMY_CPU_AU1100      2
+#define ALCHEMY_CPU_AU1550      3
+#define ALCHEMY_CPU_AU1200      4
+
+static inline int alchemy_get_cputype(void)
+{
+        switch (read_c0_prid() & 0xffff0000) {
+        case 0x00030000:
+                return ALCHEMY_CPU_AU1000;
+                break;
+        case 0x01030000:
+                return ALCHEMY_CPU_AU1500;
+                break;
+        case 0x02030000:
+                return ALCHEMY_CPU_AU1100;
+                break;
+        case 0x03030000:
+                return ALCHEMY_CPU_AU1550;
+                break;
+        case 0x04030000:
+        case 0x05030000:
+                return ALCHEMY_CPU_AU1200;
+                break;
+        }
+
+        return ALCHEMY_CPU_UNKNOWN;
+}
+
 /* arch/mips/au1000/common/clocks.c */
 extern void set_au1x00_speed(unsigned int new_freq);
 extern unsigned int get_au1x00_speed(void);