diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index 640108402ae9..da2f757cd9bc 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h
@@ -59,6 +59,18 @@ extern void vc_no_ghcb(void);
 extern void vc_boot_ghcb(void);
 extern bool handle_vc_boot_ghcb(struct pt_regs *regs);
 
+/* AMD SEV Confidential computing blob structure */
+#define CC_BLOB_SEV_HDR_MAGIC	0x45444d41
+struct cc_blob_sev_info {
+	u32 magic;
+	u16 version;
+	u16 reserved;
+	u64 secrets_phys;
+	u32 secrets_len;
+	u64 cpuid_phys;
+	u32 cpuid_len;
+};
+
 /* Software defined (when rFlags.CF = 1) */
 #define PVALIDATE_FAIL_NOUPDATE		255
 
diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h
index c0152186a008..bd64f2b98ac7 100644
--- a/arch/x86/include/uapi/asm/svm.h
+++ b/arch/x86/include/uapi/asm/svm.h
@@ -109,6 +109,7 @@
 #define SVM_VMGEXIT_SET_AP_JUMP_TABLE		0
 #define SVM_VMGEXIT_GET_AP_JUMP_TABLE		1
 #define SVM_VMGEXIT_PSC				0x80000010
+#define SVM_VMGEXIT_GUEST_REQUEST		0x80000011
 #define SVM_VMGEXIT_AP_CREATION			0x80000013
 #define SVM_VMGEXIT_AP_CREATE_ON_INIT		0
 #define SVM_VMGEXIT_AP_CREATE			1
@@ -222,6 +223,7 @@
 	{ SVM_VMGEXIT_AP_JUMP_TABLE,	"vmgexit_ap_jump_table" }, \
 	{ SVM_VMGEXIT_PSC,		"vmgexit_page_state_change" }, \
 	{ SVM_VMGEXIT_AP_CREATION,	"vmgexit_ap_creation" }, \
+	{ SVM_VMGEXIT_GUEST_REQUEST,	"vmgexit_guest_request" }, \
 	{ SVM_EXIT_ERR,         "invalid_guest_state" }
 
 
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index 8f7ef35a25ef..8aae1166f52e 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -9,6 +9,7 @@
 
 #define pr_fmt(fmt)	"SEV-ES: " fmt
 
+#include <linux/platform_device.h>
 #include <linux/sched/debug.h>	/* For show_regs() */
 #include <linux/percpu-defs.h>
 #include <linux/mem_encrypt.h>
@@ -16,10 +17,13 @@
 #include <linux/printk.h>
 #include <linux/mm_types.h>
 #include <linux/set_memory.h>
+#include <linux/sev-guest.h>
 #include <linux/memblock.h>
 #include <linux/kernel.h>
+#include <linux/efi.h>
 #include <linux/mm.h>
 #include <linux/cpumask.h>
+#include <linux/io.h>
 
 #include <asm/cpu_entry_area.h>
 #include <asm/stacktrace.h>
@@ -33,6 +37,7 @@
 #include <asm/smp.h>
 #include <asm/cpu.h>
 #include <asm/apic.h>
+#include <asm/setup.h>		/* For struct boot_params */
 
 #include "sev-internal.h"
 
@@ -47,6 +52,8 @@ static struct ghcb boot_ghcb_page __bss_decrypted __aligned(PAGE_SIZE);
  */
 static struct ghcb __initdata *boot_ghcb;
 
+static unsigned long snp_secrets_phys;
+
 /* #VC handler runtime per-CPU data */
 struct sev_es_runtime_data {
 	struct ghcb ghcb_page;
@@ -105,6 +112,10 @@ struct ghcb_state {
 	struct ghcb *ghcb;
 };
 
+#ifdef CONFIG_EFI
+extern unsigned long cc_blob_phys;
+#endif
+
 static DEFINE_PER_CPU(struct sev_es_runtime_data*, runtime_data);
 DEFINE_STATIC_KEY_FALSE(sev_es_enable_key);
 
@@ -1909,3 +1920,168 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs)
 	while (true)
 		halt();
 }
+
+static struct resource guest_req_res[0];
+static struct platform_device guest_req_device = {
+	.name		= "snp-guest",
+	.id		= -1,
+	.resource	= guest_req_res,
+	.num_resources	= 1,
+};
+
+static struct snp_secrets_page_layout *snp_map_secrets_page(void)
+{
+	u16 __iomem *secrets;
+
+	if (!snp_secrets_phys || !sev_feature_enabled(SEV_SNP))
+		return NULL;
+
+	secrets = ioremap_encrypted(snp_secrets_phys, PAGE_SIZE);
+	if (!secrets)
+		return NULL;
+
+	return (struct snp_secrets_page_layout *)secrets;
+}
+
+u64 snp_msg_seqno(void)
+{
+	struct snp_secrets_page_layout *layout;
+	u64 count;
+
+	layout = snp_map_secrets_page();
+	if (layout == NULL)
+		return 0;
+
+	/* Read the current message sequence counter from secrets pages */
+	count = readl(&layout->os_area.msg_seqno_0);
+
+	iounmap(layout);
+
+	/*
+	 * The message sequence counter for the SNP guest request is a 64-bit value
+	 * but the version 2 of GHCB specification defines the 32-bit storage for the
+	 * it.
+	 */
+	if ((count + 1) >= INT_MAX)
+		return 0;
+
+	return count + 1;
+}
+EXPORT_SYMBOL_GPL(snp_msg_seqno);
+
+static void snp_gen_msg_seqno(void)
+{
+	struct snp_secrets_page_layout *layout;
+	u64 count;
+
+	layout = snp_map_secrets_page();
+	if (layout == NULL)
+		return;
+
+	/* Increment the sequence counter by 2 and save in secrets page. */
+	count = readl(&layout->os_area.msg_seqno_0);
+	count += 2;
+
+	writel(count, &layout->os_area.msg_seqno_0);
+	iounmap(layout);
+}
+
+static int get_snp_secrets_resource(struct resource *res)
+{
+	struct setup_header *hdr = &boot_params.hdr;
+	struct cc_blob_sev_info *info;
+	unsigned long paddr;
+	int ret = -ENODEV;
+
+	/*
+	 * The secret page contains the VM encryption key used for encrypting the
+	 * messages between the guest and the PSP. The secrets page location is
+	 * available either through the setup_data or EFI configuration table.
+	 */
+	if (hdr->cc_blob_address) {
+		paddr = hdr->cc_blob_address;
+	} else if (efi_enabled(EFI_CONFIG_TABLES)) {
+#ifdef CONFIG_EFI
+		paddr = cc_blob_phys;
+#else
+		return -ENODEV;
+#endif
+	} else {
+		return -ENODEV;
+	}
+
+	info = memremap(paddr, sizeof(*info), MEMREMAP_WB);
+	if (!info)
+		return -ENOMEM;
+
+	/* Verify the header that its a valid SEV_SNP CC header */
+	if ((info->magic == CC_BLOB_SEV_HDR_MAGIC) &&
+	    info->secrets_phys &&
+	    (info->secrets_len == PAGE_SIZE)) {
+		res->start = info->secrets_phys;
+		res->end = info->secrets_phys + info->secrets_len;
+		res->flags = IORESOURCE_MEM;
+		snp_secrets_phys = info->secrets_phys;
+		ret = 0;
+	}
+
+	memunmap(info);
+	return ret;
+}
+
+static int __init add_snp_guest_request(void)
+{
+	if (!sev_feature_enabled(SEV_SNP))
+		return -ENODEV;
+
+	if (get_snp_secrets_resource(&guest_req_res[0]))
+		return -ENODEV;
+
+	platform_device_register(&guest_req_device);
+	dev_info(&guest_req_device.dev, "registered [secret 0x%llx - 0x%llx]\n",
+		guest_req_res[0].start, guest_req_res[0].end);
+
+	return 0;
+}
+device_initcall(add_snp_guest_request);
+
+unsigned long snp_issue_guest_request(int type, struct snp_guest_request_data *input)
+{
+	struct ghcb_state state;
+	struct ghcb *ghcb;
+	unsigned long id;
+	int ret;
+
+	if (!sev_feature_enabled(SEV_SNP))
+		return -ENODEV;
+
+	if (type == GUEST_REQUEST)
+		id = SVM_VMGEXIT_GUEST_REQUEST;
+	else
+		return -EINVAL;
+
+	ghcb = sev_es_get_ghcb(&state);
+	if (!ghcb)
+		return -ENODEV;
+
+	vc_ghcb_invalidate(ghcb);
+	ghcb_set_rax(ghcb, input->data_gpa);
+	ghcb_set_rbx(ghcb, input->data_npages);
+
+	ret = sev_es_ghcb_hv_call(ghcb, NULL, id, input->req_gpa, input->resp_gpa);
+	if (ret)
+		goto e_put;
+
+	if (ghcb->save.sw_exit_info_2) {
+		ret = ghcb->save.sw_exit_info_2;
+		goto e_put;
+	}
+
+	/* Command was successful, increment the message sequence counter. */
+	snp_gen_msg_seqno();
+
+e_put:
+	sev_es_put_ghcb(&state);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(snp_issue_guest_request);
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 8a26e705cb06..2cca9ee6e1d4 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -57,6 +57,7 @@ static unsigned long efi_systab_phys __initdata;
 static unsigned long prop_phys = EFI_INVALID_TABLE_ADDR;
 static unsigned long uga_phys = EFI_INVALID_TABLE_ADDR;
 static unsigned long efi_runtime, efi_nr_tables;
+unsigned long cc_blob_phys;
 
 unsigned long efi_fw_vendor, efi_config_table;
 
@@ -66,6 +67,7 @@ static const efi_config_table_type_t arch_tables[] __initconst = {
 #ifdef CONFIG_X86_UV
 	{UV_SYSTEM_TABLE_GUID,		&uv_systab_phys,	"UVsystab"	},
 #endif
+	{EFI_CC_BLOB_GUID,		&cc_blob_phys,		"CC blob"	},
 	{},
 };
 
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 6b5d36babfcc..75aeb2a56888 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -344,6 +344,7 @@ void efi_native_runtime_setup(void);
 #define EFI_CERT_SHA256_GUID			EFI_GUID(0xc1c41626, 0x504c, 0x4092, 0xac, 0xa9, 0x41, 0xf9, 0x36, 0x93, 0x43, 0x28)
 #define EFI_CERT_X509_GUID			EFI_GUID(0xa5c059a1, 0x94e4, 0x4aa7, 0x87, 0xb5, 0xab, 0x15, 0x5c, 0x2b, 0xf0, 0x72)
 #define EFI_CERT_X509_SHA256_GUID		EFI_GUID(0x3bd2a492, 0x96c0, 0x4079, 0xb4, 0x20, 0xfc, 0xf9, 0x8e, 0xf1, 0x03, 0xed)
+#define EFI_CC_BLOB_GUID			EFI_GUID(0x067b1f5f, 0xcf26, 0x44c5, 0x85, 0x54, 0x93, 0xd7, 0x77, 0x91, 0x2d, 0x42)
 
 /*
  * This GUID is used to pass to the kernel proper the struct screen_info
diff --git a/include/linux/sev-guest.h b/include/linux/sev-guest.h
new file mode 100644
index 000000000000..51277448a108
--- /dev/null
+++ b/include/linux/sev-guest.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * AMD Secure Encrypted Virtualization (SEV) guest driver interface
+ *
+ * Copyright (C) 2021 Advanced Micro Devices, Inc.
+ *
+ * Author: Brijesh Singh <brijesh.singh@amd.com>
+ *
+ */
+
+#ifndef __LINUX_SEV_GUEST_H_
+#define __LINUX_SEV_GUEST_H_
+
+#include <linux/types.h>
+
+enum vmgexit_type {
+	GUEST_REQUEST,
+
+	GUEST_REQUEST_MAX
+};
+
+/*
+ * The secrets page contains 96-bytes of reserved field that can be used by
+ * the guest OS. The guest OS uses the area to save the message sequence
+ * number for each VMPL level.
+ *
+ * See the GHCB spec section Secret page layout for the format for this area.
+ */
+struct secrets_os_area {
+	u32 msg_seqno_0;
+	u32 msg_seqno_1;
+	u32 msg_seqno_2;
+	u32 msg_seqno_3;
+	u64 ap_jump_table_pa;
+	u8 rsvd[40];
+	u8 guest_usage[32];
+} __packed;
+
+#define VMPCK_KEY_LEN		32
+
+/* See the SNP spec secrets page layout section for the structure */
+struct snp_secrets_page_layout {
+	u32 version;
+	u32 imiEn	: 1,
+	    rsvd1	: 31;
+	u32 fms;
+	u32 rsvd2;
+	u8 gosvw[16];
+	u8 vmpck0[VMPCK_KEY_LEN];
+	u8 vmpck1[VMPCK_KEY_LEN];
+	u8 vmpck2[VMPCK_KEY_LEN];
+	u8 vmpck3[VMPCK_KEY_LEN];
+	struct secrets_os_area os_area;
+	u8 rsvd3[3840];
+} __packed;
+
+struct snp_guest_request_data {
+	unsigned long req_gpa;
+	unsigned long resp_gpa;
+	unsigned long data_gpa;
+	unsigned int data_npages;
+};
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+unsigned long snp_issue_guest_request(int vmgexit_type, struct snp_guest_request_data *input);
+u64 snp_msg_seqno(void);
+#else
+
+static inline unsigned long snp_issue_guest_request(int type,
+						    struct snp_guest_request_data *input)
+{
+	return -ENODEV;
+}
+static inline u64 snp_msg_seqno(void) { return 0; }
+#endif /* CONFIG_AMD_MEM_ENCRYPT */
+#endif /* __LINUX_SEV_GUEST_H__ */
