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Diffstat (limited to 'arch/arm64/include/asm/el2_setup.h')
-rw-r--r--arch/arm64/include/asm/el2_setup.h181
1 files changed, 181 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h
new file mode 100644
index 000000000000..a7f5a1bbc8ac
--- /dev/null
+++ b/arch/arm64/include/asm/el2_setup.h
@@ -0,0 +1,181 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012,2013 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ */
+
+#ifndef __ARM_KVM_INIT_H__
+#define __ARM_KVM_INIT_H__
+
+#ifndef __ASSEMBLY__
+#error Assembly-only header
+#endif
+
+#include <asm/kvm_arm.h>
+#include <asm/ptrace.h>
+#include <asm/sysreg.h>
+#include <linux/irqchip/arm-gic-v3.h>
+
+.macro __init_el2_sctlr
+ mov_q x0, INIT_SCTLR_EL2_MMU_OFF
+ msr sctlr_el2, x0
+ isb
+.endm
+
+/*
+ * Allow Non-secure EL1 and EL0 to access physical timer and counter.
+ * This is not necessary for VHE, since the host kernel runs in EL2,
+ * and EL0 accesses are configured in the later stage of boot process.
+ * Note that when HCR_EL2.E2H == 1, CNTHCTL_EL2 has the same bit layout
+ * as CNTKCTL_EL1, and CNTKCTL_EL1 accessing instructions are redefined
+ * to access CNTHCTL_EL2. This allows the kernel designed to run at EL1
+ * to transparently mess with the EL0 bits via CNTKCTL_EL1 access in
+ * EL2.
+ */
+.macro __init_el2_timers mode
+.ifeqs "\mode", "nvhe"
+ mrs x0, cnthctl_el2
+ orr x0, x0, #3 // Enable EL1 physical timers
+ msr cnthctl_el2, x0
+.endif
+ msr cntvoff_el2, xzr // Clear virtual offset
+.endm
+
+.macro __init_el2_debug mode
+ mrs x1, id_aa64dfr0_el1
+ sbfx x0, x1, #ID_AA64DFR0_PMUVER_SHIFT, #4
+ cmp x0, #1
+ b.lt 1f // Skip if no PMU present
+ mrs x0, pmcr_el0 // Disable debug access traps
+ ubfx x0, x0, #11, #5 // to EL2 and allow access to
+1:
+ csel x2, xzr, x0, lt // all PMU counters from EL1
+
+ /* Statistical profiling */
+ ubfx x0, x1, #ID_AA64DFR0_PMSVER_SHIFT, #4
+ cbz x0, 3f // Skip if SPE not present
+
+.ifeqs "\mode", "nvhe"
+ mrs_s x0, SYS_PMBIDR_EL1 // If SPE available at EL2,
+ and x0, x0, #(1 << SYS_PMBIDR_EL1_P_SHIFT)
+ cbnz x0, 2f // then permit sampling of physical
+ mov x0, #(1 << SYS_PMSCR_EL2_PCT_SHIFT | \
+ 1 << SYS_PMSCR_EL2_PA_SHIFT)
+ msr_s SYS_PMSCR_EL2, x0 // addresses and physical counter
+2:
+ mov x0, #(MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT)
+ orr x2, x2, x0 // If we don't have VHE, then
+ // use EL1&0 translation.
+.else
+ orr x2, x2, #MDCR_EL2_TPMS // For VHE, use EL2 translation
+ // and disable access from EL1
+.endif
+
+3:
+ msr mdcr_el2, x2 // Configure debug traps
+.endm
+
+/* LORegions */
+.macro __init_el2_lor
+ mrs x1, id_aa64mmfr1_el1
+ ubfx x0, x1, #ID_AA64MMFR1_LOR_SHIFT, 4
+ cbz x0, 1f
+ msr_s SYS_LORC_EL1, xzr
+1:
+.endm
+
+/* Stage-2 translation */
+.macro __init_el2_stage2
+ msr vttbr_el2, xzr
+.endm
+
+/* GICv3 system register access */
+.macro __init_el2_gicv3
+ mrs x0, id_aa64pfr0_el1
+ ubfx x0, x0, #ID_AA64PFR0_GIC_SHIFT, #4
+ cbz x0, 1f
+
+ mrs_s x0, SYS_ICC_SRE_EL2
+ orr x0, x0, #ICC_SRE_EL2_SRE // Set ICC_SRE_EL2.SRE==1
+ orr x0, x0, #ICC_SRE_EL2_ENABLE // Set ICC_SRE_EL2.Enable==1
+ msr_s SYS_ICC_SRE_EL2, x0
+ isb // Make sure SRE is now set
+ mrs_s x0, SYS_ICC_SRE_EL2 // Read SRE back,
+ tbz x0, #0, 1f // and check that it sticks
+ msr_s SYS_ICH_HCR_EL2, xzr // Reset ICC_HCR_EL2 to defaults
+1:
+.endm
+
+.macro __init_el2_hstr
+ msr hstr_el2, xzr // Disable CP15 traps to EL2
+.endm
+
+/* Virtual CPU ID registers */
+.macro __init_el2_nvhe_idregs
+ mrs x0, midr_el1
+ mrs x1, mpidr_el1
+ msr vpidr_el2, x0
+ msr vmpidr_el2, x1
+.endm
+
+/* Coprocessor traps */
+.macro __init_el2_nvhe_cptr
+ mov x0, #0x33ff
+ msr cptr_el2, x0 // Disable copro. traps to EL2
+.endm
+
+/* SVE register access */
+.macro __init_el2_nvhe_sve
+ mrs x1, id_aa64pfr0_el1
+ ubfx x1, x1, #ID_AA64PFR0_SVE_SHIFT, #4
+ cbz x1, 1f
+
+ 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.
+1:
+.endm
+
+.macro __init_el2_nvhe_prepare_eret
+ mov x0, #INIT_PSTATE_EL1
+ msr spsr_el2, x0
+.endm
+
+/**
+ * Initialize EL2 registers to sane values. This should be called early on all
+ * cores that were booted in EL2.
+ *
+ * Regs: x0, x1 and x2 are clobbered.
+ */
+.macro init_el2_state mode
+.ifnes "\mode", "vhe"
+.ifnes "\mode", "nvhe"
+.error "Invalid 'mode' argument"
+.endif
+.endif
+
+ __init_el2_sctlr
+ __init_el2_timers \mode
+ __init_el2_debug \mode
+ __init_el2_lor
+ __init_el2_stage2
+ __init_el2_gicv3
+ __init_el2_hstr
+
+ /*
+ * When VHE is not in use, early init of EL2 needs to be done here.
+ * When VHE _is_ in use, EL1 will not be used in the host and
+ * requires no configuration, and all non-hyp-specific EL2 setup
+ * will be done via the _EL1 system register aliases in __cpu_setup.
+ */
+.ifeqs "\mode", "nvhe"
+ __init_el2_nvhe_idregs
+ __init_el2_nvhe_cptr
+ __init_el2_nvhe_sve
+ __init_el2_nvhe_prepare_eret
+.endif
+.endm
+
+#endif /* __ARM_KVM_INIT_H__ */