arm: Allow cleanup_before_linux() without disabling caches

This function is used before jumping to U-Boot, but in that case we don't
always want to disable caches.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>

arch/arm/cpu/armv7/cpu.c

@@ -24,7 +24,7 @@
 
 void __weak cpu_cache_initialization(void){}
 
-int cleanup_before_linux(void)
+int cleanup_before_linux_select(int flags)
 {
 	/*
 	 * this function is called just before we call linux
@@ -42,24 +42,30 @@ int cleanup_before_linux(void)
 	icache_disable();
 	invalidate_icache_all();
 
-	/*
-	 * turn off D-cache
-	 * dcache_disable() in turn flushes the d-cache and disables MMU
-	 */
-	dcache_disable();
-	v7_outer_cache_disable();
+	if (flags & CBL_DISABLE_CACHES) {
+		/*
+		* turn off D-cache
+		* dcache_disable() in turn flushes the d-cache and disables MMU
+		*/
+		dcache_disable();
+		v7_outer_cache_disable();
 
-	/*
-	 * After D-cache is flushed and before it is disabled there may
-	 * be some new valid entries brought into the cache. We are sure
-	 * that these lines are not dirty and will not affect our execution.
-	 * (because unwinding the call-stack and setting a bit in CP15 SCTLR
-	 * is all we did during this. We have not pushed anything on to the
-	 * stack. Neither have we affected any static data)
-	 * So just invalidate the entire d-cache again to avoid coherency
-	 * problems for kernel
-	 */
-	invalidate_dcache_all();
+		/*
+		* After D-cache is flushed and before it is disabled there may
+		* be some new valid entries brought into the cache. We are
+		* sure that these lines are not dirty and will not affect our
+		* execution. (because unwinding the call-stack and setting a
+		* bit in CP15 SCTRL is all we did during this. We have not
+		* pushed anything on to the stack. Neither have we affected
+		* any static data) So just invalidate the entire d-cache again
+		* to avoid coherency problems for kernel
+		*/
+		invalidate_dcache_all();
+	} else {
+		flush_dcache_all();
+		invalidate_icache_all();
+		icache_enable();
+	}
 
 	/*
 	 * Some CPU need more cache attention before starting the kernel.
@@ -68,3 +74,8 @@ int cleanup_before_linux(void)
 
 	return 0;
 }
+
+int cleanup_before_linux(void)
+{
+	return cleanup_before_linux_select(CBL_ALL);
+}

include/common.h

@@ -714,6 +714,21 @@ void	invalidate_dcache_range(unsigned long start, unsigned long stop);
 void	invalidate_dcache_all(void);
 void	invalidate_icache_all(void);
 
+enum {
+	/* Disable caches (else flush caches but leave them active) */
+	CBL_DISABLE_CACHES		= 1 << 0,
+	CBL_SHOW_BOOTSTAGE_REPORT	= 1 << 1,
+
+	CBL_ALL				= 3,
+};
+
+/**
+ * Clean up ready for linux
+ *
+ * @param flags		Flags to control what is done
+ */
+int cleanup_before_linux_select(int flags);
+
 /* arch/$(ARCH)/lib/ticks.S */
 uint64_t get_ticks(void);
 void	wait_ticks    (unsigned long);