This adds routines to add hyp mode vectors and switch back to HYP mode from SVC. This is needed in both the PBL and Barebox proper. Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx> Tested-by: Roland Hieber <r.hieber@xxxxxxxxxxxxxx> --- v3: - fix whitespace - use __BARE_INIT --- arch/arm/cpu/Makefile | 3 + arch/arm/cpu/hyp.S | 116 ++++++++++++++++++++++++++++++++++ arch/arm/cpu/sm_as.S | 11 ---- arch/arm/include/asm/secure.h | 3 + 4 files changed, 122 insertions(+), 11 deletions(-) create mode 100644 arch/arm/cpu/hyp.S diff --git a/arch/arm/cpu/Makefile b/arch/arm/cpu/Makefile index 374b7cda4c77..45de2728d01a 100644 --- a/arch/arm/cpu/Makefile +++ b/arch/arm/cpu/Makefile @@ -4,6 +4,9 @@ obj-$(CONFIG_ARM_EXCEPTIONS) += exceptions$(S64).o interrupts$(S64).o obj-$(CONFIG_MMU) += mmu$(S64).o lwl-y += lowlevel$(S64).o obj-pbl-$(CONFIG_MMU) += mmu-early$(S64).o +obj-pbl-y += hyp.o +AFLAGS_hyp.o :=-Wa,-march=armv7-a -Wa,-mcpu=all +AFLAGS_pbl-hyp.o :=-Wa,-march=armv7-a -Wa,-mcpu=all obj-y += start.o entry.o diff --git a/arch/arm/cpu/hyp.S b/arch/arm/cpu/hyp.S new file mode 100644 index 000000000000..1314b56eab25 --- /dev/null +++ b/arch/arm/cpu/hyp.S @@ -0,0 +1,116 @@ +#include <linux/linkage.h> +#include <asm/system.h> +#include <asm/opcodes-virt.h> +#include <init.h> + +.arch_extension sec +.arch_extension virt + +__BARE_INIT + +.data + .align 2 +ENTRY(__boot_cpu_mode) + .long 0 +.text + +ENTRY(__hyp_install) + mrs r12, cpsr + and r12, r12, #MODE_MASK + + @ Save the initial CPU state + adr r0, .L__boot_cpu_mode_offset + ldr r1, [r0] + str r12, [r0, r1] + + cmp r12, #HYP_MODE + movne pc, lr @ give up if the CPU is not in HYP mode + + @ Now install the hypervisor stub: + adr r12, __hyp_vectors + mcr p15, 4, r12, c12, c0, 0 @ set hypervisor vector base (HVBAR) + + @ Disable all traps, so we don't get any nasty surprise + mov r12, #0 + mcr p15, 4, r12, c1, c1, 0 @ HCR + mcr p15, 4, r12, c1, c1, 2 @ HCPTR + mcr p15, 4, r12, c1, c1, 3 @ HSTR + +THUMB( orr r12, #(1 << 30) ) @ HSCTLR.TE + mcr p15, 4, r12, c1, c0, 0 @ HSCTLR + + mrc p15, 4, r12, c1, c1, 1 @ HDCR + and r12, #0x1f @ Preserve HPMN + mcr p15, 4, r12, c1, c1, 1 @ HDCR + + @ Make sure NS-SVC is initialised appropriately + mrc p15, 0, r12, c1, c0, 0 @ SCTLR + orr r12, #(1 << 5) @ CP15 barriers enabled + bic r12, #(3 << 7) @ Clear SED/ITD for v8 (RES0 for v7) + bic r12, #(3 << 19) @ WXN and UWXN disabled + mcr p15, 0, r12, c1, c0, 0 @ SCTLR + + mrc p15, 0, r12, c0, c0, 0 @ MIDR + mcr p15, 4, r12, c0, c0, 0 @ VPIDR + + mrc p15, 0, r12, c0, c0, 5 @ MPIDR + mcr p15, 4, r12, c0, c0, 5 @ VMPIDR + bx lr +ENDPROC(__hyp_install) + +ENTRY(armv7_hyp_install) + mov r2, lr + + bl __hyp_install + + /* set the cpu to SVC32 mode, mask irq and fiq */ + mrs r12, cpsr + eor r12, r12, #HYP_MODE + tst r12, #MODE_MASK + bic r12, r12, #MODE_MASK + orr r12, r12, #(PSR_I_BIT | PSR_F_BIT | SVC_MODE) +THUMB( orr r12, r12, #PSR_T_BIT ) + bne 1f + orr r12, r12, #PSR_A_BIT + adr lr, 2f + msr spsr_cxsf, r12 + __MSR_ELR_HYP(14) + __ERET +1: msr cpsr_c, r12 +2: + mov pc, r2 +ENDPROC(armv7_hyp_install) + +ENTRY(armv7_switch_to_hyp) + mov r0, lr + mov r1, sp @ save SVC copy of LR and SP + isb + hvc #0 @ for older asm: .byte 0x70, 0x00, 0x40, 0xe1 + mov sp, r1 + mov lr, r0 @ restore SVC copy of LR and SP + + bx lr +ENDPROC(armv7_switch_to_hyp) + +.align 2 +.L__boot_cpu_mode_offset: + .long __boot_cpu_mode - . + +/* The HYP trap is crafted to match armv7_switch_to_hyp() */ +__hyp_do_trap: + mov lr, r0 + mov sp, r1 + bx lr +ENDPROC(__hyp_do_trap) + +.align 5 +__hyp_vectors: +__hyp_reset: W(b) . +__hyp_und: W(b) . +__hyp_svc: W(b) . +__hyp_pabort: W(b) . +__hyp_dabort: W(b) . +__hyp_trap: W(b) __hyp_do_trap +__hyp_irq: W(b) . +__hyp_fiq: W(b) . +ENDPROC(__hyp_vectors) diff --git a/arch/arm/cpu/sm_as.S b/arch/arm/cpu/sm_as.S index 0d01e1bf2435..de6cd0406f4f 100644 --- a/arch/arm/cpu/sm_as.S +++ b/arch/arm/cpu/sm_as.S @@ -148,17 +148,6 @@ hyp_trap: mov pc, lr @ do no switch modes, but @ return to caller -ENTRY(armv7_switch_to_hyp) - mov r0, lr - mov r1, sp @ save SVC copy of LR and SP - isb - hvc #0 @ for older asm: .byte 0x70, 0x00, 0x40, 0xe1 - mov sp, r1 - mov lr, r0 @ restore SVC copy of LR and SP - - bx lr -ENDPROC(armv7_switch_to_hyp) - ENTRY(psci_cpu_entry) mrc p15, 0, r0, c1, c0, 1 @ ACTLR orr r0, r0, #(1 << 6) @ Set SMP bit diff --git a/arch/arm/include/asm/secure.h b/arch/arm/include/asm/secure.h index a4cb1f6c1c44..663d81ea27dd 100644 --- a/arch/arm/include/asm/secure.h +++ b/arch/arm/include/asm/secure.h @@ -5,9 +5,12 @@ int armv7_secure_monitor_install(void); int __armv7_secure_monitor_install(void); + void armv7_switch_to_hyp(void); +void armv7_hyp_install(void); extern unsigned char secure_monitor_init_vectors[]; +extern int __boot_cpu_mode; enum arm_security_state { ARM_STATE_SECURE, -- 2.19.1 _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox