[3/9] hw/arm/boot: If booting a kernel in EL2, set SCR_EL3.HCE

Message ID 20180313153458.26822-4-peter.maydell@linaro.org
State Superseded
Headers show
Series
  • raspi3: various fixes for Linux booting
Related show

Commit Message

Peter Maydell March 13, 2018, 3:34 p.m.
If we're directly booting a Linux kernel and the CPU supports both
EL3 and EL2, we start the kernel in EL2, as it expects. We must also
set the SCR_EL3.HCE bit in this situation, so that the HVC
instruction is enabled rather than UNDEFing. Otherwise at least some
kernels will panic when trying to initialize KVM in the guest.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

---
 hw/arm/boot.c | 5 +++++
 1 file changed, 5 insertions(+)

-- 
2.16.2

Patch

diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index e21a92f972..9319b12fcd 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -729,6 +729,11 @@  static void do_cpu_reset(void *opaque)
                     assert(!info->secure_board_setup);
                 }
 
+                if (arm_feature(env, ARM_FEATURE_EL2)) {
+                    /* If we have EL2 then Linux expects the HVC insn to work */
+                    env->cp15.scr_el3 |= SCR_HCE;
+                }
+
                 /* Set to non-secure if not a secure boot */
                 if (!info->secure_boot &&
                     (cs != first_cpu || !info->secure_board_setup)) {