[PATCH v2 18/21] riscv: link ELF image into PBL

[Sascha Hauer <s.hauer@pengutronix.de>]

Instead of linking the raw binary barebox proper image into the PBL link
the ELF image into the PBL. With this barebox proper starts with a properly
linked and fully initialized C environment, so the calls to
relocate_to_adr() and setup_c() can be removed from barebox proper.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 arch/riscv/Kconfig           |  1 +
 arch/riscv/boot/start.c      |  6 ------
 arch/riscv/boot/uncompress.c | 21 ++++++++++++++++++++-
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 96d013d8514ac12de5c34a426262d85f8cf021b9..d9794354f4ed2e8bf7276e03b968c566002c2ec6 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -17,6 +17,7 @@ config RISCV
 	select HAS_KALLSYMS
 	select RISCV_TIMER if RISCV_SBI
 	select HW_HAS_PCI
+	select PBL_IMAGE_ELF
 	select HAVE_ARCH_BOARD_GENERIC_DT
 	select HAVE_ARCH_BOOTM_OFTREE
 
diff --git a/arch/riscv/boot/start.c b/arch/riscv/boot/start.c
index 5091340c8a374fc360ab732ba01ec8516e82a83d..002ab3eccb4292d8d88a95f8b93163c970cb1d64 100644
--- a/arch/riscv/boot/start.c
+++ b/arch/riscv/boot/start.c
@@ -123,12 +123,6 @@ void barebox_non_pbl_start(unsigned long membase, unsigned long memsize,
 	unsigned long barebox_size = barebox_image_size + MAX_BSS_SIZE;
 	unsigned long barebox_base = riscv_mem_barebox_image(membase, endmem, barebox_size);
 
-	relocate_to_current_adr();
-
-	setup_c();
-
-	barrier();
-
 	irq_init_vector(riscv_mode());
 
 	pr_debug("memory at 0x%08lx, size 0x%08lx\n", membase, memsize);
diff --git a/arch/riscv/boot/uncompress.c b/arch/riscv/boot/uncompress.c
index 84142acf9c66fe1fcceb6ae63d15ac078ccddee7..fba04cf4fb6ed450d80b83a8a595346a3186f1e7 100644
--- a/arch/riscv/boot/uncompress.c
+++ b/arch/riscv/boot/uncompress.c
@@ -32,6 +32,8 @@ void __noreturn barebox_pbl_start(unsigned long membase, unsigned long memsize,
 	unsigned long barebox_base;
 	void *pg_start, *pg_end;
 	unsigned long pc = get_pc();
+	struct elf_image elf;
+	int ret;
 
 	irq_init_vector(riscv_mode());
 
@@ -68,7 +70,24 @@ void __noreturn barebox_pbl_start(unsigned long membase, unsigned long memsize,
 
 	sync_caches_for_execution();
 
-	barebox = (void *)barebox_base;
+	ret = elf_open_binary_into(&elf, (void *)barebox_base);
+	if (ret) {
+		pr_err("Failed to open ELF binary: %d\n", ret);
+		hang();
+	}
+
+	ret = elf_load_inplace(&elf);
+	if (ret) {
+		pr_err("Failed to relocate ELF: %d\n", ret);
+		hang();
+	}
+
+	/*
+	 * TODO: Add pbl_mmu_setup_from_elf() call when RISC-V PBL
+	 * MMU support is implemented, similar to ARM
+	 */
+
+	barebox = (void *)elf.entry;
 
 	pr_debug("jumping to uncompressed image at 0x%p. dtb=0x%p\n", barebox, fdt);
 

-- 
2.47.3