From b739f22a99c96d5a295f083125505b5b5ec2f8b6 Mon Sep 17 00:00:00 2001 From: Achin Gupta Date: Sat, 18 Jan 2014 16:50:09 +0000 Subject: [PATCH] Setup VBAR_EL3 incrementally This patch ensures that VBAR_EL3 points to the simple stack-less 'early_exceptions' when the C runtime stack is not correctly setup to use the more complex 'runtime_exceptions'. It is initialised to 'runtime_exceptions' once this is done. This patch also moves all exception vectors into a '.vectors' section and modifies linker scripts to place all such sections together. This will minimize space wastage from alignment restrictions. Change-Id: I8c3e596ea3412c8bd582af9e8d622bb1cb2e049d --- bl1/aarch64/early_exceptions.S | 9 +++++---- bl1/bl1.ld.S | 1 + bl2/bl2.ld.S | 1 + bl31/aarch64/bl31_entrypoint.S | 10 +++++++++- bl31/aarch64/runtime_exceptions.S | 4 ++-- bl31/bl31.ld.S | 1 + bl31/bl31.mk | 3 ++- common/psci/psci_afflvl_on.c | 1 - common/psci/psci_afflvl_suspend.c | 2 -- common/psci/psci_entry.S | 21 +++++++++++++++++++++ include/aarch64/arch.h | 1 - 11 files changed, 42 insertions(+), 12 deletions(-) diff --git a/bl1/aarch64/early_exceptions.S b/bl1/aarch64/early_exceptions.S index ef47f9e3..84bdae16 100644 --- a/bl1/aarch64/early_exceptions.S +++ b/bl1/aarch64/early_exceptions.S @@ -37,12 +37,12 @@ .globl early_exceptions .weak display_boot_progress - .section .text, "ax"; .align 11 + .section .vectors, "ax"; .align 11 /* ----------------------------------------------------- - * Very simple exception handlers used by BL1 and BL2. - * Apart from one SMC exception all other traps loop - * endlessly. + * Very simple stackless exception handlers used by all + * bootloader stages. BL31 uses them before stacks are + * setup. BL1/BL2 use them throughout. * ----------------------------------------------------- */ .align 7 @@ -164,6 +164,7 @@ SErrorA32: .align 7 + .section .text, "ax" process_exception: sub sp, sp, #0x40 stp x0, x1, [sp, #0x0] diff --git a/bl1/bl1.ld.S b/bl1/bl1.ld.S index 969b8c27..ac52e529 100644 --- a/bl1/bl1.ld.S +++ b/bl1/bl1.ld.S @@ -45,6 +45,7 @@ SECTIONS *bl1_entrypoint.o(.text) *(.text) *(.rodata*) + *(.vectors) __RO_END__ = .; } >ROM diff --git a/bl2/bl2.ld.S b/bl2/bl2.ld.S index 849297a7..77eb2010 100644 --- a/bl2/bl2.ld.S +++ b/bl2/bl2.ld.S @@ -49,6 +49,7 @@ SECTIONS *bl2_entrypoint.o(.text) *(.text) *(.rodata*) + *(.vectors) __RO_END_UNALIGNED__ = .; /* * Memory page(s) mapped to this section will be marked as diff --git a/bl31/aarch64/bl31_entrypoint.S b/bl31/aarch64/bl31_entrypoint.S index 57f65515..cd0c0235 100644 --- a/bl31/aarch64/bl31_entrypoint.S +++ b/bl31/aarch64/bl31_entrypoint.S @@ -58,7 +58,7 @@ bl31_entrypoint: ; .type bl31_entrypoint, %function * Set the exception vector to something sane. * --------------------------------------------- */ - adr x1, runtime_exceptions + adr x1, early_exceptions msr vbar_el3, x1 /* --------------------------------------------------------------------- @@ -154,6 +154,14 @@ bl31_entrypoint: ; .type bl31_entrypoint, %function mov x0, x19 bl platform_set_stack + /* --------------------------------------------- + * Use the more complex exception vectors now + * the stacks are setup. + * --------------------------------------------- + */ + adr x1, runtime_exceptions + msr vbar_el3, x1 + /* --------------------------------------------- * Use SP_EL0 to initialize BL31. It allows us * to jump to the next image without having to diff --git a/bl31/aarch64/runtime_exceptions.S b/bl31/aarch64/runtime_exceptions.S index ce0af744..92835dcb 100644 --- a/bl31/aarch64/runtime_exceptions.S +++ b/bl31/aarch64/runtime_exceptions.S @@ -37,8 +37,8 @@ #include - .section .text, "ax"; .align 11 - + .section .vectors, "ax"; .align 11 + .align 7 runtime_exceptions: /* ----------------------------------------------------- diff --git a/bl31/bl31.ld.S b/bl31/bl31.ld.S index 7cc85273..2583c9a3 100644 --- a/bl31/bl31.ld.S +++ b/bl31/bl31.ld.S @@ -50,6 +50,7 @@ SECTIONS *bl31_entrypoint.o(.text) *(.text) *(.rodata*) + *(.vectors) __RO_END_UNALIGNED__ = .; /* * Memory page(s) mapped to this section will be marked as read-only, diff --git a/bl31/bl31.mk b/bl31/bl31.mk index 5c374aa1..f7c21688 100644 --- a/bl31/bl31.mk +++ b/bl31/bl31.mk @@ -62,7 +62,8 @@ BL31_OBJS += bl31_arch_setup.o \ spinlock.o \ gic_v3_sysregs.o \ bakery_lock.o \ - runtime_svc.o + runtime_svc.o \ + early_exceptions.o BL31_ENTRY_POINT := bl31_entrypoint BL31_MAPFILE := bl31.map diff --git a/common/psci/psci_afflvl_on.c b/common/psci/psci_afflvl_on.c index 83d47d57..14f524c8 100644 --- a/common/psci/psci_afflvl_on.c +++ b/common/psci/psci_afflvl_on.c @@ -353,7 +353,6 @@ static unsigned int psci_afflvl0_on_finish(unsigned long mpidr, /* * Arch. management: Turn on mmu & restore architectural state */ - write_vbar((unsigned long) runtime_exceptions); enable_mmu(); /* diff --git a/common/psci/psci_afflvl_suspend.c b/common/psci/psci_afflvl_suspend.c index 2abcafb3..f3748402 100644 --- a/common/psci/psci_afflvl_suspend.c +++ b/common/psci/psci_afflvl_suspend.c @@ -115,7 +115,6 @@ static int psci_afflvl0_suspend(unsigned long mpidr, psci_suspend_context[index].sec_sysregs.mair = read_mair(); psci_suspend_context[index].sec_sysregs.tcr = read_tcr(); psci_suspend_context[index].sec_sysregs.ttbr = read_ttbr0(); - psci_suspend_context[index].sec_sysregs.vbar = read_vbar(); psci_suspend_context[index].sec_sysregs.pstate = read_daif() & (DAIF_ABT_BIT | DAIF_DBG_BIT); @@ -424,7 +423,6 @@ static unsigned int psci_afflvl0_suspend_finish(unsigned long mpidr, * Arch. management: Restore the stashed secure architectural * context in the right order. */ - write_vbar(psci_suspend_context[index].sec_sysregs.vbar); write_daif(read_daif() | psci_suspend_context[index].sec_sysregs.pstate); write_mair(psci_suspend_context[index].sec_sysregs.mair); write_tcr(psci_suspend_context[index].sec_sysregs.tcr); diff --git a/common/psci/psci_entry.S b/common/psci/psci_entry.S index a6a1a6f0..28a41436 100644 --- a/common/psci/psci_entry.S +++ b/common/psci/psci_entry.S @@ -63,6 +63,17 @@ psci_aff_suspend_finish_entry: psci_aff_common_finish_entry: adr x22, psci_afflvl_power_on_finish + + /* --------------------------------------------- + * Exceptions should not occur at this point. + * Set VBAR in order to handle and report any + * that do occur + * --------------------------------------------- + */ + adr x0, early_exceptions + msr vbar_el3, x0 + isb + bl read_mpidr mov x19, x0 bl platform_set_coherent_stack @@ -90,6 +101,16 @@ psci_aff_common_finish_entry: mov x0, x19 bl platform_set_stack + /* --------------------------------------------- + * Now that the execution stack has been set + * up, enable full runtime exception handling. + * Since we're just about to leave this EL with + * ERET, we don't need an ISB here + * --------------------------------------------- + */ + adr x0, runtime_exceptions + msr vbar_el3, x0 + /* -------------------------------------------- * Use the size of the general purpose register * context to restore the register state diff --git a/include/aarch64/arch.h b/include/aarch64/arch.h index 10d2adb7..f40e1487 100644 --- a/include/aarch64/arch.h +++ b/include/aarch64/arch.h @@ -326,7 +326,6 @@ typedef struct { unsigned long mair; unsigned long tcr; unsigned long ttbr; - unsigned long vbar; unsigned long pstate; } sysregs_context; -- 2.30.2