[PATCH v4 06/21] arm64: Move VHE-specific SPE setup to mutate_to_vhe()

Marc Zyngier
2021-01-18T10:07:17Z

There isn't much that a VHE kernel needs on top of whatever has
been done for nVHE, so let's move the little we need to the
VHE stub (the SPE setup), and drop the init_el2_state macro.

No expected functional change.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kernel/hyp-stub.S | 28 +++++++++++++++++++++++++---
1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S
index 52b29c54a9f7..59820f9b8522 100644
--- a/arch/arm64/kernel/hyp-stub.S
+++ b/arch/arm64/kernel/hyp-stub.S
@@ -89,9 +89,6 @@ SYM_CODE_START_LOCAL(mutate_to_vhe)
msr hcr_el2, x0
isb

- // Doesn't do much on VHE, but still, worth a shot
- init_el2_state vhe
-
// Use the EL1 allocated stack, per-cpu offset
mrs x0, sp_el1
mov sp, x0
@@ -104,6 +101,31 @@ SYM_CODE_START_LOCAL(mutate_to_vhe)
mrs_s x0, SYS_VBAR_EL12
msr vbar_el1, x0

+ // Fixup SPE configuration, if supported...
+ mrs x1, id_aa64dfr0_el1
+ ubfx x1, x1, #ID_AA64DFR0_PMSVER_SHIFT, #4
+ mov x2, xzr
+ cbz x1, skip_spe
+
+ // ... and not owned by EL3
+ mrs_s x0, SYS_PMBIDR_EL1
+ and x0, x0, #(1 << SYS_PMBIDR_EL1_P_SHIFT)
+ cbnz x0, skip_spe
+
+ // Let the SPE driver in control of the sampling
+ mrs_s x0, SYS_PMSCR_EL1
+ bic x0, x0, #(1 << SYS_PMSCR_EL2_PCT_SHIFT)
+ bic x0, x0, #(1 << SYS_PMSCR_EL2_PA_SHIFT)
+ msr_s SYS_PMSCR_EL1, x0
+ mov x2, #MDCR_EL2_TPMS
+
+skip_spe:
+ // For VHE, use EL2 translation and disable access from EL1
+ mrs x0, mdcr_el2
+ bic x0, x0, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)
+ orr x0, x0, x2
+ msr mdcr_el2, x0
+
// Transfer the MM state from EL1 to EL2
mrs_s x0, SYS_TCR_EL12
msr tcr_el1, x0
--
2.29.2