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authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-15 10:56:56 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-15 10:56:56 -0800
commitc9b012e5f4a1d01dfa8abc6318211a67ba7d5db2 (patch)
tree97b2f1c654fc4333e9e3111f76a26ec5503ee5b9 /arch/arm64/kernel/head.S
parentb293fca43be544483b6488d33ad4b3ed55881064 (diff)
parent6cfa7cc46b1a7a15d81d5389c99cfca633c12b8e (diff)
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon: "The big highlight is support for the Scalable Vector Extension (SVE) which required extensive ABI work to ensure we don't break existing applications by blowing away their signal stack with the rather large new vector context (<= 2 kbit per vector register). There's further work to be done optimising things like exception return, but the ABI is solid now. Much of the line count comes from some new PMU drivers we have, but they're pretty self-contained and I suspect we'll have more of them in future. Plenty of acronym soup here: - initial support for the Scalable Vector Extension (SVE) - improved handling for SError interrupts (required to handle RAS events) - enable GCC support for 128-bit integer types - remove kernel text addresses from backtraces and register dumps - use of WFE to implement long delay()s - ACPI IORT updates from Lorenzo Pieralisi - perf PMU driver for the Statistical Profiling Extension (SPE) - perf PMU driver for Hisilicon's system PMUs - misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits) arm64: Make ARMV8_DEPRECATED depend on SYSCTL arm64: Implement __lshrti3 library function arm64: support __int128 on gcc 5+ arm64/sve: Add documentation arm64/sve: Detect SVE and activate runtime support arm64/sve: KVM: Hide SVE from CPU features exposed to guests arm64/sve: KVM: Treat guest SVE use as undefined instruction execution arm64/sve: KVM: Prevent guests from using SVE arm64/sve: Add sysctl to set the default vector length for new processes arm64/sve: Add prctl controls for userspace vector length management arm64/sve: ptrace and ELF coredump support arm64/sve: Preserve SVE registers around EFI runtime service calls arm64/sve: Preserve SVE registers around kernel-mode NEON use arm64/sve: Probe SVE capabilities and usable vector lengths arm64: cpufeature: Move sys_caps_initialised declarations arm64/sve: Backend logic for setting the vector length arm64/sve: Signal handling support arm64/sve: Support vector length resetting for new processes arm64/sve: Core task context handling arm64/sve: Low-level CPU setup ...
Diffstat (limited to 'arch/arm64/kernel/head.S')
-rw-r--r--arch/arm64/kernel/head.S30
1 files changed, 24 insertions, 6 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 0b243ecaf7ac..67e86a0f57ac 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -480,14 +480,21 @@ set_hcr:
/* Statistical profiling */
ubfx x0, x1, #32, #4 // Check ID_AA64DFR0_EL1 PMSVer
- cbz x0, 6f // Skip if SPE not present
- cbnz x2, 5f // VHE?
+ cbz x0, 7f // Skip if SPE not present
+ cbnz x2, 6f // VHE?
+ mrs_s x4, SYS_PMBIDR_EL1 // If SPE available at EL2,
+ and x4, x4, #(1 << SYS_PMBIDR_EL1_P_SHIFT)
+ cbnz x4, 5f // then permit sampling of physical
+ mov x4, #(1 << SYS_PMSCR_EL2_PCT_SHIFT | \
+ 1 << SYS_PMSCR_EL2_PA_SHIFT)
+ msr_s SYS_PMSCR_EL2, x4 // addresses and physical counter
+5:
mov x1, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)
orr x3, x3, x1 // If we don't have VHE, then
- b 6f // use EL1&0 translation.
-5: // For VHE, use EL2 translation
+ b 7f // use EL1&0 translation.
+6: // For VHE, use EL2 translation
orr x3, x3, #MDCR_EL2_TPMS // and disable access from EL1
-6:
+7:
msr mdcr_el2, x3 // Configure debug traps
/* Stage-2 translation */
@@ -517,8 +524,19 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems
mov x0, #0x33ff
msr cptr_el2, x0 // Disable copro. traps to EL2
+ /* SVE register access */
+ mrs x1, id_aa64pfr0_el1
+ ubfx x1, x1, #ID_AA64PFR0_SVE_SHIFT, #4
+ cbz x1, 7f
+
+ bic x0, x0, #CPTR_EL2_TZ // Also disable SVE traps
+ msr cptr_el2, x0 // Disable copro. traps to EL2
+ isb
+ mov x1, #ZCR_ELx_LEN_MASK // SVE: Enable full vector
+ msr_s SYS_ZCR_EL2, x1 // length for EL1.
+
/* Hypervisor stub */
- adr_l x0, __hyp_stub_vectors
+7: adr_l x0, __hyp_stub_vectors
msr vbar_el2, x0
/* spsr */