arm/lib/bootm.c: keep ARM v7M in thumb mode during boot_jump_linux()

On ARM v7M, the processor will return to ARM mode when executing
a blx instruction with bit 0 of the address == 0. Always set it
to 1 to stay in thumb mode.

Tested on STM32f746-disco board

Similar commit:
f99993c10882f7dc8ec35993d5febe59aac01e6a
Author: Matt Porter <mporter@konsulko.com>

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>

diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
index 426bee6..4dbe6a5 100644 (file)
--- a/arch/arm/lib/bootm.c
+++ b/arch/arm/lib/bootm.c
@@ -356,7 +356,10 @@ static void boot_jump_linux(bootm_headers_t *images, int flag)
        int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
 
        kernel_entry = (void (*)(int, int, uint))images->ep;
-
+#ifdef CONFIG_CPU_V7M
+       ulong addr = (ulong)kernel_entry | 1;
+       kernel_entry = (void *)addr;
+#endif
        s = getenv("machid");
        if (s) {
                if (strict_strtoul(s, 16, &machid) < 0) {