MIPS: mm: init: Add free_init_pages() callback for EVA

A core in EVA mode can have any possible segment mapping, so the
default free_initmem_default() function may not always work as expected.
Therefore, add a callback that platforms can use to free up the init section.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

arch/mips/include/asm/bootinfo.h

@@ -112,6 +112,8 @@ extern void prom_free_prom_memory(void);
 extern void free_init_pages(const char *what,
 			    unsigned long begin, unsigned long end);
 
+extern void (*free_init_pages_eva)(void *begin, void *end);
+
 /*
  * Initial kernel command line, usually setup by prom_init()
  */

arch/mips/mm/init.c

@@ -422,10 +422,20 @@ void free_initrd_mem(unsigned long start, unsigned long end)
 }
 #endif
 
+void (*free_init_pages_eva)(void *begin, void *end) = NULL;
+
 void __init_refok free_initmem(void)
 {
 	prom_free_prom_memory();
-	free_initmem_default(POISON_FREE_INITMEM);
+	/*
+	 * Let the platform define a specific function to free the
+	 * init section since EVA may have used any possible mapping
+	 * between virtual and physical addresses.
+	 */
+	if (free_init_pages_eva)
+		free_init_pages_eva((void *)&__init_begin, (void *)&__init_end);
+	else
+		free_initmem_default(POISON_FREE_INITMEM);
 }
 
 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT