Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 169 insertions, 0 deletions

diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S
new file mode 100644
index 000000000..538652866
--- /dev/null
+++ b/arch/arm/kvm/init.S
@@ -0,0 +1,169 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.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, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/unified.h>
+#include <asm/asm-offsets.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+#include <asm/virt.h>
+
+/********************************************************************
+ * Hypervisor initialization
+ *   - should be called with:
+ *       r0 = top of Hyp stack (kernel VA)
+ *       r1 = pointer to hyp vectors
+ *       r2,r3 = Hypervisor pgd pointer
+ *
+ * The init scenario is:
+ * - We jump in HYP with 3 parameters: runtime HYP pgd, runtime stack,
+ *   runtime vectors
+ * - Invalidate TLBs
+ * - Set stack and vectors
+ * - Setup the page tables
+ * - Enable the MMU
+ * - Profit! (or eret, if you only care about the code).
+ *
+ * Another possibility is to get a HYP stub hypercall.
+ * We discriminate between the two by checking if r0 contains a value
+ * that is less than HVC_STUB_HCALL_NR.
+ */
+
+	.text
+	.pushsection    .hyp.idmap.text,"ax"
+	.align 5
+__kvm_hyp_init:
+	.globl __kvm_hyp_init
+
+	@ Hyp-mode exception vector
+	W(b)	.
+	W(b)	.
+	W(b)	.
+	W(b)	.
+	W(b)	.
+	W(b)	__do_hyp_init
+	W(b)	.
+	W(b)	.
+
+__do_hyp_init:
+	@ Check for a stub hypercall
+	cmp	r0, #HVC_STUB_HCALL_NR
+	blo	__kvm_handle_stub_hvc
+
+	@ Set stack pointer
+	mov	sp, r0
+
+	@ Set HVBAR to point to the HYP vectors
+	mcr	p15, 4, r1, c12, c0, 0	@ HVBAR
+
+	@ Set the HTTBR to point to the hypervisor PGD pointer passed
+	mcrr	p15, 4, rr_lo_hi(r2, r3), c2
+
+	@ Set the HTCR and VTCR to the same shareability and cacheability
+	@ settings as the non-secure TTBCR and with T0SZ == 0.
+	mrc	p15, 4, r0, c2, c0, 2	@ HTCR
+	ldr	r2, =HTCR_MASK
+	bic	r0, r0, r2
+	mrc	p15, 0, r1, c2, c0, 2	@ TTBCR
+	and	r1, r1, #(HTCR_MASK & ~TTBCR_T0SZ)
+	orr	r0, r0, r1
+	mcr	p15, 4, r0, c2, c0, 2	@ HTCR
+
+	@ Use the same memory attributes for hyp. accesses as the kernel
+	@ (copy MAIRx ro HMAIRx).
+	mrc	p15, 0, r0, c10, c2, 0
+	mcr	p15, 4, r0, c10, c2, 0
+	mrc	p15, 0, r0, c10, c2, 1
+	mcr	p15, 4, r0, c10, c2, 1
+
+	@ Invalidate the stale TLBs from Bootloader
+	mcr	p15, 4, r0, c8, c7, 0	@ TLBIALLH
+	dsb	ish
+
+	@ Set the HSCTLR to:
+	@  - ARM/THUMB exceptions: Kernel config (Thumb-2 kernel)
+	@  - Endianness: Kernel config
+	@  - Fast Interrupt Features: Kernel config
+	@  - Write permission implies XN: disabled
+	@  - Instruction cache: enabled
+	@  - Data/Unified cache: enabled
+	@  - MMU: enabled (this code must be run from an identity mapping)
+	mrc	p15, 4, r0, c1, c0, 0	@ HSCR
+	ldr	r2, =HSCTLR_MASK
+	bic	r0, r0, r2
+	mrc	p15, 0, r1, c1, c0, 0	@ SCTLR
+	ldr	r2, =(HSCTLR_EE | HSCTLR_FI | HSCTLR_I | HSCTLR_C)
+	and	r1, r1, r2
+ ARM(	ldr	r2, =(HSCTLR_M)					)
+ THUMB(	ldr	r2, =(HSCTLR_M | HSCTLR_TE)			)
+	orr	r1, r1, r2
+	orr	r0, r0, r1
+	mcr	p15, 4, r0, c1, c0, 0	@ HSCR
+	isb
+
+	eret
+
+ENTRY(__kvm_handle_stub_hvc)
+	cmp	r0, #HVC_SOFT_RESTART
+	bne	1f
+
+	/* The target is expected in r1 */
+	msr	ELR_hyp, r1
+	mrs	r0, cpsr
+	bic	r0, r0, #MODE_MASK
+	orr	r0, r0, #HYP_MODE
+THUMB(	orr	r0, r0, #PSR_T_BIT	)
+	msr	spsr_cxsf, r0
+	b	reset
+
+1:	cmp	r0, #HVC_RESET_VECTORS
+	bne	1f
+
+reset:
+	/* We're now in idmap, disable MMU */
+	mrc	p15, 4, r1, c1, c0, 0	@ HSCTLR
+	ldr	r0, =(HSCTLR_M | HSCTLR_A | HSCTLR_C | HSCTLR_I)
+	bic	r1, r1, r0
+	mcr	p15, 4, r1, c1, c0, 0	@ HSCTLR
+
+	/*
+	 * Install stub vectors, using ardb's VA->PA trick.
+	 */
+0:	adr	r0, 0b					@ PA(0)
+	movw	r1, #:lower16:__hyp_stub_vectors - 0b   @ VA(stub) - VA(0)
+	movt	r1, #:upper16:__hyp_stub_vectors - 0b
+	add	r1, r1, r0				@ PA(stub)
+	mcr	p15, 4, r1, c12, c0, 0	@ HVBAR
+	b	exit
+
+1:	ldr	r0, =HVC_STUB_ERR
+	eret
+
+exit:
+	mov	r0, #0
+	eret
+ENDPROC(__kvm_handle_stub_hvc)
+
+	.ltorg
+
+	.globl __kvm_hyp_init_end
+__kvm_hyp_init_end:
+
+	.popsection