sparc32,leon: fix leon bootup

head_32.S failed to set cputypval for leon, causing boot to fail.
The boot failed because we failed to recognize this was a LEON
cpu so we did not preoperly run-time patch the the kernel.
This resulted in an early crash.

Reported-by: Daniel Hellstrom <daniel@gaisler.com>
Tested-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Konrad Eisele <konrad@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 41 insertions, 32 deletions

diff --git a/arch/sparc/kernel/head_32.S b/arch/sparc/kernel/head_32.S
index cdc7f29ba17b..5364a05177c2 100644
--- a/arch/sparc/kernel/head_32.S
+++ b/arch/sparc/kernel/head_32.S
@@ -372,36 +372,9 @@ execute_in_high_mem:
                 sethi   %hi(linux_dbvec), %g1
                 st      %o1, [%g1 + %lo(linux_dbvec)]
 
-                /* Check if this is a LEON CPU.
-                 * Skip getprops call if it is
+                /* Get the machine type via the romvec
+                 * getprops node operation
                  */
-                srl     %g3, PSR_IMPL_SHIFT, %g3
-                and     %g3, PSR_IMPL_SHIFTED_MASK, %g3
-                cmp     %g3, PSR_IMPL_LEON
-                 bne    get_cputype
-
-
-                /* LEON CPU - set boot_cpu_id */
-                sethi   %hi(boot_cpu_id), %g2   ! boot-cpu index
-
-#ifdef CONFIG_SMP
-                ldub    [%g2 + %lo(boot_cpu_id)], %g1
-                cmp     %g1, 0xff               ! unset means first CPU
-                bne     leon_smp_cpu_startup    ! continue only with master
-                 nop
-#endif
-                /* Get CPU-ID from most significant 4-bit of ASR17 */
-                rd     %asr17, %g1
-                srl    %g1, 28, %g1
-
-                /* Update boot_cpu_id only on boot cpu */
-                stub    %g1, [%g2 + %lo(boot_cpu_id)]
-
-                ba continue_boot
-                 nop
-
-/* Get the machine type via the mysterious romvec node operations. */
-get_cputype:
                 add     %g7, 0x1c, %l1
                 ld      [%l1], %l0
                 ld      [%l0], %l0
@@ -420,10 +393,26 @@ get_cputype:
                                                 ! to a buf where above string
                                                 ! will get stored by the prom.
 
-/* Check to cputype. We may be booted on a sun4u (64 bit box),
- * and sun4d needs special treatment.
- */
+
+                /* Check value of "compatible" property.
+                 * "value" => "model"
+                 * leon => sparc_leon
+                 * sun4m => sun4m
+                 * sun4s => sun4m
+                 * sun4d => sun4d
+                 * sun4e => "no_sun4e_here"
+                 * '*'   => "no_sun4u_here"
+                 * Check single letters only
+                 */
+
                 set     cputypval, %o2
+                /* If cputypval[0] == 'l' (lower case letter L) this is leon */
+                ldub    [%o2], %l1
+                cmp     %l1, 'l'
+                be      leon_init
+                 nop
+
+                /* Check cputypval[4] to find the sun model */
                 ldub    [%o2 + 0x4], %l1
 
                 cmp     %l1, 'm'
@@ -438,6 +427,26 @@ get_cputype:
                 b       no_sun4u_here           ! AIEEE, a V9 sun4u... Get our BIG BROTHER kernel :))
                  nop
 
+leon_init:
+                /* LEON CPU - set boot_cpu_id */
+                sethi   %hi(boot_cpu_id), %g2   ! boot-cpu index
+
+#ifdef CONFIG_SMP
+                ldub    [%g2 + %lo(boot_cpu_id)], %g1
+                cmp     %g1, 0xff               ! unset means first CPU
+                bne     leon_smp_cpu_startup    ! continue only with master
+                 nop
+#endif
+                /* Get CPU-ID from most significant 4-bit of ASR17 */
+                rd     %asr17, %g1
+                srl    %g1, 28, %g1
+
+                /* Update boot_cpu_id only on boot cpu */
+                stub    %g1, [%g2 + %lo(boot_cpu_id)]
+
+                ba continue_boot
+                 nop
+
 /* CPUID in bootbus can be found at PA 0xff0140000 */
 #define SUN4D_BOOTBUS_CPUID     0xf0140000