[PATCH 3/4] imx: bootaux: get stack from elf file

Peng Fan (OSS)
2022-04-29T07:22:05Z

To i.MX8, M core stack is pre-coded in source code, so need to get it
before kicking M core. The stack pointer is stored in the first word of
the first PT_LOAD section __isr_vector. So use a num to index the
section loading.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
arch/arm/mach-imx/imx_bootaux.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-imx/imx_bootaux.c b/arch/arm/mach-imx/imx_bootaux.c
index 3c6a5c09b7d..8115bf40f1a 100644
--- a/arch/arm/mach-imx/imx_bootaux.c
+++ b/arch/arm/mach-imx/imx_bootaux.c
@@ -42,10 +42,11 @@ static const struct rproc_att *get_host_mapping(unsigned long auxcore)
* is valid, returns the entry point address.
* Translates load addresses in the elf file to the U-Boot address space.
*/
-static unsigned long load_elf_image_m_core_phdr(unsigned long addr)
+static unsigned long load_elf_image_m_core_phdr(unsigned long addr, ulong *stack)
{
Elf32_Ehdr *ehdr; /* ELF header structure pointer */
Elf32_Phdr *phdr; /* Program header structure pointer */
+ int num = 0;
int i;

ehdr = (Elf32_Ehdr *)addr;
@@ -71,8 +72,13 @@ static unsigned long load_elf_image_m_core_phdr(unsigned long addr)
debug("Loading phdr %i to 0x%p (%i bytes)\n",
i, dst, phdr->p_filesz);

- if (phdr->p_filesz)
+ if (phdr->p_filesz) {
memcpy(dst, src, phdr->p_filesz);
+ /* Stack in __isr_vector is the first section/word */
+ if (!num)
+ *stack = *(uint32_t *)src;
+ num++;
+ }
if (phdr->p_filesz != phdr->p_memsz)
memset(dst + phdr->p_filesz, 0x00,
phdr->p_memsz - phdr->p_filesz);
@@ -96,11 +102,12 @@ int arch_auxiliary_core_up(u32 core_id, ulong addr)
* isn't supported yet.
*/
if (valid_elf_image(addr)) {
- stack = 0x0;
- pc = load_elf_image_m_core_phdr(addr);
+ pc = load_elf_image_m_core_phdr(addr, &stack);
if (!pc)
return CMD_RET_FAILURE;

+ if (!CONFIG_IS_ENABLED(ARM64))
+ stack = 0x0;
} else {
/*
* Assume binary file with vector table at the beginning.
--
2.36.0