[PATCH 2/4] mips: add KSEG1 wrapper for change_k0_cca

[Daniel Schwierzeck]

change_k0_cca() is called multiple times. Move the code for
changing to KSEG1 to a macro to avoid code duplication.

Also fix missing change to KSEG1 when changing to CONF_CM_CACHABLE_COW.

Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>
---

 arch/mips/lib/cache_init.S | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/arch/mips/lib/cache_init.S b/arch/mips/lib/cache_init.S
index cfad1d9c8a..2233d27137 100644
--- a/arch/mips/lib/cache_init.S
+++ b/arch/mips/lib/cache_init.S
@@ -79,6 +79,21 @@
 	.set	pop
 	.endm
 
+	/*
+	 * The changing of Kernel mode cacheability must be done from KSEG1.
+	 * If the code is executing from KSEG0, jump to KSEG1 during the execution
+	 * of change_k0_cca. change_k0_cca itself clears all hazards when returning.
+	 */
+	.macro change_k0_cca_kseg1 mode
+	PTR_LA	t0, change_k0_cca
+	li	t1, CPHYSADDR(~0)
+	and	t0, t0, t1
+	PTR_LI	t1, CKSEG1
+	or	t0, t0, t1
+	li	a0, \mode
+	jalr	t0
+	.endm
+
 /*
  * mips_cache_reset - low level initialisation of the primary caches
  *
@@ -317,18 +332,9 @@ l1_init:
 	sync
 
 	/*
-	 * Enable use of the I-cache by setting Config.K0. The code for this
-	 * must be executed from KSEG1. Jump from KSEG0 to KSEG1 to do this.
-	 * Jump back to KSEG0 after caches are enabled and insert an
-	 * instruction hazard barrier.
+	 * Enable use of the I-cache by setting Config.K0.
 	 */
-	PTR_LA		t0, change_k0_cca
-	li		t1, CPHYSADDR(~0)
-	and		t0, t0, t1
-	PTR_LI		t1, CKSEG1
-	or		t0, t0, t1
-	li		a0, CONF_CM_CACHABLE_NONCOHERENT
-	jalr.hb		t0
+	change_k0_cca_kseg1 CONF_CM_CACHABLE_NONCOHERENT
 
 	/*
 	 * then initialize D-cache.
@@ -388,9 +394,7 @@ l2_unbypass:
 	beqz		t0, 2f
 
 	/* Change Config.K0 to a coherent CCA */
-	PTR_LA		t0, change_k0_cca
-	li		a0, CONF_CM_CACHABLE_COW
-	jalr		t0
+	change_k0_cca_kseg1 CONF_CM_CACHABLE_COW
 
 	/*
 	 * Join the coherent domain such that the caches of this core are kept
-- 
2.27.0