aarch32: use lr as bl32 boot argument on aarch32 only systems

Add 'lr_svc' as a boot parameter in AArch32 bl1. This is used by Optee
and Trusty to get the non-secure entry point on AArch32 platforms.

This change is not ported in AArch64 mode where the BL31, not BL32,
is in charge of booting the non secure image (BL33).

Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

diff --git a/bl1/aarch32/bl1_exceptions.S b/bl1/aarch32/bl1_exceptions.S
index f73db4022d97e93cb30797fff2c2e3b1736717e4..a1e32f06fd9de378fdcf479cbd73f731981b8b12 100644 (file)
--- a/bl1/aarch32/bl1_exceptions.S
+++ b/bl1/aarch32/bl1_exceptions.S
@@ -73,6 +73,11 @@ debug_loop:
        ldr     r1, [r8, #(ENTRY_POINT_INFO_PC_OFFSET + 4)]
        msr     spsr, r1
 
+       /* Some BL32 stages expect lr_svc to provide the BL33 entry address */
+       cps     #MODE32_svc
+       ldr     lr, [r8, #ENTRY_POINT_INFO_LR_SVC_OFFSET]
+       cps     #MODE32_mon
+
        add     r8, r8, #ENTRY_POINT_INFO_ARGS_OFFSET
        ldm     r8, {r0, r1, r2, r3}
        eret

diff --git a/include/common/ep_info.h b/include/common/ep_info.h
index 3f6213f047968e423ac83f8f28616a6cd63358e2..3c2fe4443339accd4f1044c8c753aa86d982cfb0 100644 (file)
--- a/include/common/ep_info.h
+++ b/include/common/ep_info.h
@@ -20,7 +20,8 @@
  ******************************************************************************/
 #define ENTRY_POINT_INFO_PC_OFFSET     U(0x08)
 #ifdef AARCH32
-#define ENTRY_POINT_INFO_ARGS_OFFSET   U(0x10)
+#define ENTRY_POINT_INFO_LR_SVC_OFFSET U(0x10)
+#define ENTRY_POINT_INFO_ARGS_OFFSET   U(0x14)
 #else
 #define ENTRY_POINT_INFO_ARGS_OFFSET   U(0x18)
 #endif
@@ -93,6 +94,7 @@ typedef struct entry_point_info {
        uintptr_t pc;
        uint32_t spsr;
 #ifdef AARCH32
+       uintptr_t lr_svc;
        aapcs32_params_t args;
 #else
        aapcs64_params_t args;
@@ -108,6 +110,12 @@ CASSERT(ENTRY_POINT_INFO_PC_OFFSET ==
                __builtin_offsetof(entry_point_info_t, pc), \
                assert_BL31_pc_offset_mismatch);
 
+#ifdef AARCH32
+CASSERT(ENTRY_POINT_INFO_LR_SVC_OFFSET ==
+               __builtin_offsetof(entry_point_info_t, lr_svc),
+               assert_entrypoint_lr_offset_error);
+#endif
+
 CASSERT(ENTRY_POINT_INFO_ARGS_OFFSET == \
                __builtin_offsetof(entry_point_info_t, args), \
                assert_BL31_args_offset_mismatch);