feat(plat/rcar3): add optional support for gzip-compressed BL33

The BL33 size on this platform is limited to 1 MiB, add optional
support for decompressing and starting gzip-compressed BL33, which
may help with this size limitation. This functionality is disabled
by default, set RCAR_GEN3_BL33_GZIP=1 during build to enable it.

The BL33 at 0x50000000 should then be gzip compressed, however if
the BL33 does not have a valid gzip header, it is copied to the
correct location and started as-is, this is a fallback for legacy
systems and systems which update to gzip-compressed BL33.
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Change-Id: Id93f1c7e6f17db1ffb952ea086562993473f6efa

plat/renesas/common/include/platform_def.h

@@ -151,7 +151,8 @@
  * BL33
  ******************************************************************************/
 #define BL33_BASE		DRAM1_NS_BASE
-
+#define BL33_COMP_SIZE		U(0x200000)
+#define BL33_COMP_BASE		(BL33_BASE - BL33_COMP_SIZE)
 
 /*******************************************************************************
  * Platform specific page table and MMU setup constants

plat/renesas/rcar/bl2_plat_setup.c

@@ -15,12 +15,16 @@
 #include <common/bl_common.h>
 #include <common/debug.h>
 #include <common/desc_image_load.h>
+#include <common/image_decompress.h>
 #include <drivers/console.h>
 #include <drivers/io/io_driver.h>
 #include <drivers/io/io_storage.h>
 #include <lib/mmio.h>
 #include <lib/xlat_tables/xlat_tables_defs.h>
 #include <plat/common/platform.h>
+#if RCAR_GEN3_BL33_GZIP == 1
+#include <tf_gunzip.h>
+#endif
 
 #include "avs_driver.h"
 #include "boot_init_dram.h"
@@ -357,16 +361,29 @@ static uint32_t is_ddr_backup_mode(void)
 #endif
 }
 
+#if RCAR_GEN3_BL33_GZIP == 1
+void bl2_plat_preload_setup(void)
+{
+	image_decompress_init(BL33_COMP_BASE, BL33_COMP_SIZE, gunzip);
+}
+#endif
+
 int bl2_plat_handle_pre_image_load(unsigned int image_id)
 {
 	u_register_t *boot_kind = (void *) BOOT_KIND_BASE;
 	bl_mem_params_node_t *bl_mem_params;
 
+	bl_mem_params = get_bl_mem_params_node(image_id);
+
+#if RCAR_GEN3_BL33_GZIP == 1
+	if (image_id == BL33_IMAGE_ID) {
+		image_decompress_prepare(&bl_mem_params->image_info);
+	}
+#endif
+
 	if (image_id != BL31_IMAGE_ID)
 		return 0;
 
-	bl_mem_params = get_bl_mem_params_node(image_id);
-
 	if (is_ddr_backup_mode() == RCAR_COLD_BOOT)
 		goto cold_boot;
 
@@ -433,6 +450,19 @@ int bl2_plat_handle_post_image_load(unsigned int image_id)
 			sizeof(entry_point_info_t));
 		break;
 	case BL33_IMAGE_ID:
+#if RCAR_GEN3_BL33_GZIP == 1
+		if ((mmio_read_32(BL33_COMP_BASE) & 0xffff) == 0x8b1f) {
+			/* decompress gzip-compressed image */
+			ret = image_decompress(&bl_mem_params->image_info);
+			if (ret != 0) {
+				return ret;
+			}
+		} else {
+			/* plain image, copy it in place */
+			memcpy((void *)BL33_BASE, (void *)BL33_COMP_BASE,
+				bl_mem_params->image_info.image_size);
+		}
+#endif
 		memcpy(&params->bl33_ep_info, &bl_mem_params->ep_info,
 			sizeof(entry_point_info_t));
 		break;

plat/renesas/rcar/platform.mk

@@ -280,6 +280,11 @@ RCAR_SYSTEM_RESET_KEEPON_DDR := 0
 endif
 $(eval $(call add_define,RCAR_SYSTEM_RESET_KEEPON_DDR))
 
+ifndef RCAR_GEN3_BL33_GZIP
+RCAR_GEN3_BL33_GZIP := 0
+endif
+$(eval $(call add_define,RCAR_GEN3_BL33_GZIP))
+
 # RCAR_SYSTEM_RESET_KEEPON_DDR requires power control of PMIC etc.
 # When executing SYSTEM_SUSPEND other than Salvator-X, Salvator-XS and Ebisu,
 # processing equivalent to that implemented in PMIC_ROHM_BD9571 is necessary.
@@ -315,6 +320,13 @@ PLAT_INCLUDES	+=	-Idrivers/renesas/common/ddr		\
 BL2_SOURCES	+=	plat/renesas/rcar/bl2_plat_setup.c	\
 			drivers/renesas/rcar/board/board.c
 
+ifeq (${RCAR_GEN3_BL33_GZIP},1)
+include lib/zlib/zlib.mk
+
+BL2_SOURCES	+=	common/image_decompress.c               \
+			$(ZLIB_SOURCES)
+endif
+
 ifeq (${RCAR_GEN3_ULCB},1)
 BL31_SOURCES		+=	drivers/renesas/rcar/cpld/ulcb_cpld.c
 endif