MIPS: Add CONFIG_SKIP_LOWLEVEL_INIT

This patch adds the CONFIG_SKIP_LOWLEVEL_INIT option to start.S. This
enables support for boards where the lowlevel initialization is
already done when U-Boot runs (e.g. via OnChip ROM).

This will be used in the upcoming VCTH board support.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>

diff --git a/cpu/mips/start.S b/cpu/mips/start.S
index 6a22302..f6069b3 100644 (file)
--- a/cpu/mips/start.S
+++ b/cpu/mips/start.S
@@ -243,9 +243,11 @@ reset:
        mtc0    zero, CP0_COUNT
        mtc0    zero, CP0_COMPARE
 
+#if !defined(CONFIG_SKIP_LOWLEVEL_INIT)
        /* CONFIG0 register */
        li      t0, CONF_CM_UNCACHED
        mtc0    t0, CP0_CONFIG
+#endif /* !CONFIG_SKIP_LOWLEVEL_INIT */
 
        /* Initialize $gp.
         */
@@ -255,6 +257,7 @@ reset:
 1:
        lw      gp, 0(ra)
 
+#if !defined(CONFIG_SKIP_LOWLEVEL_INIT)
        /* Initialize any external memory.
         */
        la      t9, lowlevel_init
@@ -271,6 +274,7 @@ reset:
         */
        li      t0, CONF_CM_CACHABLE_NONCOHERENT
        mtc0    t0, CP0_CONFIG
+#endif /* !CONFIG_SKIP_LOWLEVEL_INIT */
 
        /* Set up temporary stack.
         */