plat/arm: Save BL2 descriptors to reserved memory.
On ARM platforms, the BL2 memory can be overlaid by BL31/BL32. The memory
descriptors describing the list of executable images are created in BL2
R/W memory, which could be possibly corrupted later on by BL31/BL32 due
to overlay. This patch creates a reserved location in SRAM for these
descriptors and are copied over by BL2 before handing over to next BL
image.
Also this patch increases the PLAT_ARM_MAX_BL2_SIZE for juno when TBBR
is enabled.
Fixes ARM-Software/tf-issues#626
Change-Id: I755735706fa702024b4032f51ed4895b3687377f
Signed-off-by: Sathees Balya <sathees.balya@arm.com>
diff --git a/plat/arm/common/arm_image_load.c b/plat/arm/common/arm_image_load.c
index bf1fbfd..74018d2 100644
--- a/plat/arm/common/arm_image_load.c
+++ b/plat/arm/common/arm_image_load.c
@@ -4,6 +4,7 @@
* SPDX-License-Identifier: BSD-3-Clause
*/
+#include <assert.h>
#include <common/bl_common.h>
#include <common/desc_image_load.h>
#include <plat/common/platform.h>
@@ -14,6 +15,7 @@
#pragma weak plat_get_bl_image_load_info
#pragma weak plat_get_next_bl_params
+static bl_params_t *next_bl_params_cpy_ptr;
/*******************************************************************************
* This function flushes the data structures so that they are visible
@@ -21,7 +23,11 @@
******************************************************************************/
void plat_flush_next_bl_params(void)
{
- flush_bl_params_desc();
+ assert(next_bl_params_cpy_ptr != NULL);
+
+ flush_bl_params_desc_args(bl_mem_params_desc_ptr,
+ bl_mem_params_desc_num,
+ next_bl_params_cpy_ptr);
}
/*******************************************************************************
@@ -33,12 +39,53 @@
}
/*******************************************************************************
- * This function returns the list of executable images.
+ * ARM helper function to return the list of executable images.Since the default
+ * descriptors are allocated within BL2 RW memory, this prevents BL31/BL32
+ * overlay of BL2 memory. Hence this function also copies the descriptors to a
+ * pre-allocated memory indicated by ARM_BL2_MEM_DESC_BASE.
+ ******************************************************************************/
+struct bl_params *arm_get_next_bl_params(void)
+{
+ bl_mem_params_node_t *bl2_mem_params_descs_cpy
+ = (bl_mem_params_node_t *)ARM_BL2_MEM_DESC_BASE;
+ const bl_params_t *next_bl_params;
+
+ next_bl_params_cpy_ptr =
+ (bl_params_t *)(ARM_BL2_MEM_DESC_BASE +
+ (bl_mem_params_desc_num * sizeof(bl_mem_params_node_t)));
+
+ /*
+ * Copy the memory descriptors to ARM_BL2_MEM_DESC_BASE area.
+ */
+ (void) memcpy(bl2_mem_params_descs_cpy, bl_mem_params_desc_ptr,
+ (bl_mem_params_desc_num * sizeof(bl_mem_params_node_t)));
+
+ /*
+ * Modify the global 'bl_mem_params_desc_ptr' to point to the
+ * copied location.
+ */
+ bl_mem_params_desc_ptr = bl2_mem_params_descs_cpy;
+
+ next_bl_params = get_next_bl_params_from_mem_params_desc();
+ assert(next_bl_params != NULL);
+
+ /*
+ * Copy 'next_bl_params' to the reserved location after the copied
+ * memory descriptors.
+ */
+ (void) memcpy(next_bl_params_cpy_ptr, next_bl_params,
+ (sizeof(bl_params_t)));
+
+ populate_next_bl_params_config(next_bl_params_cpy_ptr);
+
+ return next_bl_params_cpy_ptr;
+}
+
+/*******************************************************************************
+ * This function returns the list of executable images
******************************************************************************/
struct bl_params *plat_get_next_bl_params(void)
{
- bl_params_t *next_bl_params = get_next_bl_params_from_mem_params_desc();
-
- populate_next_bl_params_config(next_bl_params);
- return next_bl_params;
+ return arm_get_next_bl_params();
}
+