target/linux/bcm4908/patches-6.6/301-arm64-don-t-issue-HVC-on-boot.patch

   1 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
   2 Date: Thu, 12 Aug 2021 11:52:42 +0200
   3 Subject: [PATCH] arm64: don't issue HVC on boot
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   7
   8 Broadcom's CFE loader seems to miss setting SCR_EL3.HCE which results in
   9 generating an UNDEF and kernel panic on the first HVC.
  10
  11 HVC gets issued by kernels 5.12+ while booting, by kexec and KVM. Until
  12 someone finds a workaround we have to avoid all above.
  13
  14 Workarounds: 0c93df9622d4 ("arm64: Initialise as nVHE before switching to VHE")
  15 Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
  16 ---
  17  arch/arm64/kernel/hyp-stub.S | 2 +-
  18  1 file changed, 1 insertion(+), 1 deletion(-)
  19
  20 --- a/arch/arm64/kernel/hyp-stub.S
  21 +++ b/arch/arm64/kernel/hyp-stub.S
  22 @@ -252,7 +252,7 @@ SYM_FUNC_START(finalise_el2)
  23         b.ne    1f
  24
  25         mov     x0, #HVC_FINALISE_EL2
  26 -       hvc     #0
  27 +//     hvc     #0
  28  1:
  29         ret
  30  SYM_FUNC_END(finalise_el2)