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Diffstat (limited to 'arch/arm64/kvm/hyp/s2-setup.c')
-rw-r--r--arch/arm64/kvm/hyp/s2-setup.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/s2-setup.c b/arch/arm64/kvm/hyp/s2-setup.c
new file mode 100644
index 000000000..bcbe761a5
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+++ b/arch/arm64/kvm/hyp/s2-setup.c
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2016 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/types.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_hyp.h>
+
+u32 __hyp_text __init_stage2_translation(void)
+{
+ u64 val = VTCR_EL2_FLAGS;
+ u64 parange;
+ u64 tmp;
+
+ /*
+ * Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS
+ * bits in VTCR_EL2. Amusingly, the PARange is 4 bits, while
+ * PS is only 3. Fortunately, bit 19 is RES0 in VTCR_EL2...
+ */
+ parange = read_sysreg(id_aa64mmfr0_el1) & 7;
+ val |= parange << 16;
+
+ /* Compute the actual PARange... */
+ switch (parange) {
+ case 0:
+ parange = 32;
+ break;
+ case 1:
+ parange = 36;
+ break;
+ case 2:
+ parange = 40;
+ break;
+ case 3:
+ parange = 42;
+ break;
+ case 4:
+ parange = 44;
+ break;
+ case 5:
+ default:
+ parange = 48;
+ break;
+ }
+
+ /*
+ * ... and clamp it to 40 bits, unless we have some braindead
+ * HW that implements less than that. In all cases, we'll
+ * return that value for the rest of the kernel to decide what
+ * to do.
+ */
+ val |= 64 - (parange > 40 ? 40 : parange);
+
+ /*
+ * Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS
+ * bit in VTCR_EL2.
+ */
+ tmp = (read_sysreg(id_aa64mmfr1_el1) >> ID_AA64MMFR1_VMIDBITS_SHIFT) & 0xf;
+ val |= (tmp == ID_AA64MMFR1_VMIDBITS_16) ?
+ VTCR_EL2_VS_16BIT :
+ VTCR_EL2_VS_8BIT;
+
+ write_sysreg(val, vtcr_el2);
+
+ return parange;
+}