ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/x86/mm/mem_encrypt_boot.S b/marvell/linux/arch/x86/mm/mem_encrypt_boot.S
new file mode 100644
index 0000000..6d71481
--- /dev/null
+++ b/marvell/linux/arch/x86/mm/mem_encrypt_boot.S
@@ -0,0 +1,156 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AMD Memory Encryption Support
+ *
+ * Copyright (C) 2016 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ */
+
+#include <linux/linkage.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/processor-flags.h>
+#include <asm/msr-index.h>
+#include <asm/nospec-branch.h>
+
+ .text
+ .code64
+ENTRY(sme_encrypt_execute)
+
+ /*
+ * Entry parameters:
+ * RDI - virtual address for the encrypted mapping
+ * RSI - virtual address for the decrypted mapping
+ * RDX - length to encrypt
+ * RCX - virtual address of the encryption workarea, including:
+ * - stack page (PAGE_SIZE)
+ * - encryption routine page (PAGE_SIZE)
+ * - intermediate copy buffer (PMD_PAGE_SIZE)
+ * R8 - physcial address of the pagetables to use for encryption
+ */
+
+ push %rbp
+ movq %rsp, %rbp /* RBP now has original stack pointer */
+
+ /* Set up a one page stack in the non-encrypted memory area */
+ movq %rcx, %rax /* Workarea stack page */
+ leaq PAGE_SIZE(%rax), %rsp /* Set new stack pointer */
+ addq $PAGE_SIZE, %rax /* Workarea encryption routine */
+
+ push %r12
+ movq %rdi, %r10 /* Encrypted area */
+ movq %rsi, %r11 /* Decrypted area */
+ movq %rdx, %r12 /* Area length */
+
+ /* Copy encryption routine into the workarea */
+ movq %rax, %rdi /* Workarea encryption routine */
+ leaq __enc_copy(%rip), %rsi /* Encryption routine */
+ movq $(.L__enc_copy_end - __enc_copy), %rcx /* Encryption routine length */
+ rep movsb
+
+ /* Setup registers for call */
+ movq %r10, %rdi /* Encrypted area */
+ movq %r11, %rsi /* Decrypted area */
+ movq %r8, %rdx /* Pagetables used for encryption */
+ movq %r12, %rcx /* Area length */
+ movq %rax, %r8 /* Workarea encryption routine */
+ addq $PAGE_SIZE, %r8 /* Workarea intermediate copy buffer */
+
+ ANNOTATE_RETPOLINE_SAFE
+ call *%rax /* Call the encryption routine */
+
+ pop %r12
+
+ movq %rbp, %rsp /* Restore original stack pointer */
+ pop %rbp
+
+ ret
+ENDPROC(sme_encrypt_execute)
+
+ENTRY(__enc_copy)
+/*
+ * Routine used to encrypt memory in place.
+ * This routine must be run outside of the kernel proper since
+ * the kernel will be encrypted during the process. So this
+ * routine is defined here and then copied to an area outside
+ * of the kernel where it will remain and run decrypted
+ * during execution.
+ *
+ * On entry the registers must be:
+ * RDI - virtual address for the encrypted mapping
+ * RSI - virtual address for the decrypted mapping
+ * RDX - address of the pagetables to use for encryption
+ * RCX - length of area
+ * R8 - intermediate copy buffer
+ *
+ * RAX - points to this routine
+ *
+ * The area will be encrypted by copying from the non-encrypted
+ * memory space to an intermediate buffer and then copying from the
+ * intermediate buffer back to the encrypted memory space. The physical
+ * addresses of the two mappings are the same which results in the area
+ * being encrypted "in place".
+ */
+ /* Enable the new page tables */
+ mov %rdx, %cr3
+
+ /* Flush any global TLBs */
+ mov %cr4, %rdx
+ andq $~X86_CR4_PGE, %rdx
+ mov %rdx, %cr4
+ orq $X86_CR4_PGE, %rdx
+ mov %rdx, %cr4
+
+ push %r15
+ push %r12
+
+ movq %rcx, %r9 /* Save area length */
+ movq %rdi, %r10 /* Save encrypted area address */
+ movq %rsi, %r11 /* Save decrypted area address */
+
+ /* Set the PAT register PA5 entry to write-protect */
+ movl $MSR_IA32_CR_PAT, %ecx
+ rdmsr
+ mov %rdx, %r15 /* Save original PAT value */
+ andl $0xffff00ff, %edx /* Clear PA5 */
+ orl $0x00000500, %edx /* Set PA5 to WP */
+ wrmsr
+
+ wbinvd /* Invalidate any cache entries */
+
+ /* Copy/encrypt up to 2MB at a time */
+ movq $PMD_PAGE_SIZE, %r12
+1:
+ cmpq %r12, %r9
+ jnb 2f
+ movq %r9, %r12
+
+2:
+ movq %r11, %rsi /* Source - decrypted area */
+ movq %r8, %rdi /* Dest - intermediate copy buffer */
+ movq %r12, %rcx
+ rep movsb
+
+ movq %r8, %rsi /* Source - intermediate copy buffer */
+ movq %r10, %rdi /* Dest - encrypted area */
+ movq %r12, %rcx
+ rep movsb
+
+ addq %r12, %r11
+ addq %r12, %r10
+ subq %r12, %r9 /* Kernel length decrement */
+ jnz 1b /* Kernel length not zero? */
+
+ /* Restore PAT register */
+ movl $MSR_IA32_CR_PAT, %ecx
+ rdmsr
+ mov %r15, %rdx /* Restore original PAT value */
+ wrmsr
+
+ pop %r12
+ pop %r15
+
+ ret
+.L__enc_copy_end:
+ENDPROC(__enc_copy)