diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index c2da92f19ccd..fae1fd45eccd 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -29,6 +29,7 @@
 
 #include <asm/smp.h>
 #include <asm/cacheflush.h>
+#include <asm/e820/types.h>
 
 #include "psp-dev.h"
 #include "sev-dev.h"
@@ -37,6 +38,10 @@
 #define SEV_FW_FILE		"amd/sev.fw"
 #define SEV_FW_NAME_SIZE	64
 
+/* Minimum firmware version required for the SEV-SNP support */
+#define SNP_MIN_API_MAJOR	1
+#define SNP_MIN_API_MINOR	51
+
 static DEFINE_MUTEX(sev_cmd_mutex);
 static struct sev_misc_dev *misc_dev;
 
@@ -80,6 +85,14 @@ static void *sev_es_tmr;
 #define NV_LENGTH (32 * 1024)
 static void *sev_init_ex_buffer;
 
+/*
+ * SEV_DATA_RANGE_LIST:
+ *   Array containing range of pages that firmware transitions to HV-fixed
+ *   page state.
+ */
+struct sev_data_range_list *snp_range_list;
+static int __sev_snp_init_locked(int *error);
+
 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
 {
 	struct sev_device *sev = psp_master->sev_data;
@@ -466,9 +479,9 @@ static inline int __sev_do_init_locked(int *psp_ret)
 		return __sev_init_locked(psp_ret);
 }
 
-static int __sev_platform_init_locked(int *error)
+static int ___sev_platform_init_locked(int *error, bool probe)
 {
-	int rc = 0, psp_ret = SEV_RET_NO_FW_CALL;
+	int rc, psp_ret = SEV_RET_NO_FW_CALL;
 	struct psp_device *psp = psp_master;
 	struct sev_device *sev;
 
@@ -480,6 +493,34 @@ static int __sev_platform_init_locked(int *error)
 	if (sev->state == SEV_STATE_INIT)
 		return 0;
 
+	/*
+	 * Legacy guests cannot be running while SNP_INIT(_EX) is executing,
+	 * so perform SEV-SNP initialization at probe time.
+	 */
+	rc = __sev_snp_init_locked(error);
+	if (rc && rc != -ENODEV) {
+		/*
+		 * Don't abort the probe if SNP INIT failed,
+		 * continue to initialize the legacy SEV firmware.
+		 */
+		dev_err(sev->dev, "SEV-SNP: failed to INIT rc %d, error %#x\n", rc, *error);
+	}
+
+	/* Delay SEV/SEV-ES support initialization */
+	if (probe && !psp_init_on_probe)
+		return 0;
+
+	if (!sev_es_tmr) {
+		/* Obtain the TMR memory area for SEV-ES use */
+		sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
+		if (sev_es_tmr)
+			/* Must flush the cache before giving it to the firmware */
+			clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE);
+		else
+			dev_warn(sev->dev,
+				 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
+		}
+
 	if (sev_init_ex_buffer) {
 		rc = sev_read_init_ex_file();
 		if (rc)
@@ -522,6 +563,11 @@ static int __sev_platform_init_locked(int *error)
 	return 0;
 }
 
+static int __sev_platform_init_locked(int *error)
+{
+	return ___sev_platform_init_locked(error, false);
+}
+
 int sev_platform_init(int *error)
 {
 	int rc;
@@ -534,6 +580,17 @@ int sev_platform_init(int *error)
 }
 EXPORT_SYMBOL_GPL(sev_platform_init);
 
+static int sev_platform_init_on_probe(int *error)
+{
+	int rc;
+
+	mutex_lock(&sev_cmd_mutex);
+	rc = ___sev_platform_init_locked(error, true);
+	mutex_unlock(&sev_cmd_mutex);
+
+	return rc;
+}
+
 static int __sev_platform_shutdown_locked(int *error)
 {
 	struct sev_device *sev = psp_master->sev_data;
@@ -838,6 +895,191 @@ static int sev_update_firmware(struct device *dev)
 	return ret;
 }
 
+static void snp_set_hsave_pa(void *arg)
+{
+	wrmsrl(MSR_VM_HSAVE_PA, 0);
+}
+
+static int snp_filter_reserved_mem_regions(struct resource *rs, void *arg)
+{
+	struct sev_data_range_list *range_list = arg;
+	struct sev_data_range *range = &range_list->ranges[range_list->num_elements];
+	size_t size;
+
+	if ((range_list->num_elements * sizeof(struct sev_data_range) +
+	     sizeof(struct sev_data_range_list)) > PAGE_SIZE)
+		return -E2BIG;
+
+	switch (rs->desc) {
+	case E820_TYPE_RESERVED:
+	case E820_TYPE_PMEM:
+	case E820_TYPE_ACPI:
+		range->base = rs->start & PAGE_MASK;
+		size = (rs->end + 1) - rs->start;
+		range->page_count = size >> PAGE_SHIFT;
+		range_list->num_elements++;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int __sev_snp_init_locked(int *error)
+{
+	struct psp_device *psp = psp_master;
+	struct sev_data_snp_init_ex data;
+	struct sev_device *sev;
+	int rc = 0;
+
+	if (!cpu_feature_enabled(X86_FEATURE_SEV_SNP))
+		return -ENODEV;
+
+	if (!psp || !psp->sev_data)
+		return -ENODEV;
+
+	sev = psp->sev_data;
+
+	if (sev->snp_initialized)
+		return 0;
+
+	if (!sev_version_greater_or_equal(SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR)) {
+		dev_dbg(sev->dev, "SEV-SNP support requires firmware version >= %d:%d\n",
+			SNP_MIN_API_MAJOR, SNP_MIN_API_MINOR);
+		return 0;
+	}
+
+	/*
+	 * The SNP_INIT requires the MSR_VM_HSAVE_PA must be set to 0h
+	 * across all cores.
+	 */
+	on_each_cpu(snp_set_hsave_pa, NULL, 1);
+
+	/*
+	 * Starting in SNP firmware v1.52, the SNP_INIT_EX command takes a list of
+	 * system physical address ranges to convert into the HV-fixed page states
+	 * during the RMP initialization.  For instance, the memory that UEFI
+	 * reserves should be included in the range list. This allows system
+	 * components that occasionally write to memory (e.g. logging to UEFI
+	 * reserved regions) to not fail due to RMP initialization and SNP enablement.
+	 */
+	if (sev_version_greater_or_equal(SNP_MIN_API_MAJOR, 52)) {
+		/*
+		 * Firmware checks that the pages containing the ranges enumerated
+		 * in the RANGES structure are either in the Default page state or in the
+		 * firmware page state.
+		 */
+		snp_range_list = kzalloc(PAGE_SIZE, GFP_KERNEL);
+		if (!snp_range_list) {
+			dev_err(sev->dev,
+				"SEV: SNP_INIT_EX range list memory allocation failed\n");
+			return -ENOMEM;
+		}
+
+		/*
+		 * Retrieve all reserved memory regions setup by UEFI from the e820 memory map
+		 * to be setup as HV-fixed pages.
+		 */
+
+		rc = walk_iomem_res_desc(IORES_DESC_NONE, IORESOURCE_MEM, 0, ~0,
+					 snp_range_list, snp_filter_reserved_mem_regions);
+		if (rc) {
+			dev_err(sev->dev,
+				"SEV: SNP_INIT_EX walk_iomem_res_desc failed rc = %d\n", rc);
+			return rc;
+		}
+
+		memset(&data, 0, sizeof(data));
+		data.init_rmp = 1;
+		data.list_paddr_en = 1;
+		data.list_paddr = __psp_pa(snp_range_list);
+
+		/*
+		 * Before invoking SNP_INIT_EX with INIT_RMP=1, make sure that
+		 * all dirty cache lines containing the RMP are flushed.
+		 *
+		 * NOTE: that includes writes via RMPUPDATE instructions, which
+		 * are also cacheable writes.
+		 */
+		wbinvd_on_all_cpus();
+
+		rc = __sev_do_cmd_locked(SEV_CMD_SNP_INIT_EX, &data, error);
+		if (rc)
+			return rc;
+	} else {
+		/*
+		 * SNP_INIT is equivalent to SNP_INIT_EX with INIT_RMP=1, so
+		 * just as with that case, make sure all dirty cache lines
+		 * containing the RMP are flushed.
+		 */
+		wbinvd_on_all_cpus();
+
+		rc = __sev_do_cmd_locked(SEV_CMD_SNP_INIT, NULL, error);
+		if (rc)
+			return rc;
+	}
+
+	/* Prepare for first SNP guest launch after INIT */
+	wbinvd_on_all_cpus();
+	rc = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, error);
+	if (rc)
+		return rc;
+
+	sev->snp_initialized = true;
+	dev_dbg(sev->dev, "SEV-SNP firmware initialized\n");
+
+	return rc;
+}
+
+static int __sev_snp_shutdown_locked(int *error)
+{
+	struct sev_device *sev = psp_master->sev_data;
+	struct sev_data_snp_shutdown_ex data;
+	int ret;
+
+	if (!sev->snp_initialized)
+		return 0;
+
+	memset(&data, 0, sizeof(data));
+	data.length = sizeof(data);
+	data.iommu_snp_shutdown = 1;
+
+	wbinvd_on_all_cpus();
+
+retry:
+	ret = __sev_do_cmd_locked(SEV_CMD_SNP_SHUTDOWN_EX, &data, error);
+	/* SHUTDOWN may require DF_FLUSH */
+	if (*error == SEV_RET_DFFLUSH_REQUIRED) {
+		ret = __sev_do_cmd_locked(SEV_CMD_SNP_DF_FLUSH, NULL, NULL);
+		if (ret) {
+			dev_err(sev->dev, "SEV-SNP DF_FLUSH failed\n");
+			return ret;
+		}
+		goto retry;
+	}
+	if (ret) {
+		dev_err(sev->dev, "SEV-SNP firmware shutdown failed\n");
+		return ret;
+	}
+
+	sev->snp_initialized = false;
+	dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
+
+	return ret;
+}
+
+static int sev_snp_shutdown(int *error)
+{
+	int rc;
+
+	mutex_lock(&sev_cmd_mutex);
+	rc = __sev_snp_shutdown_locked(error);
+	mutex_unlock(&sev_cmd_mutex);
+
+	return rc;
+}
+
 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
 {
 	struct sev_device *sev = psp_master->sev_data;
@@ -1285,6 +1527,8 @@ int sev_dev_init(struct psp_device *psp)
 
 static void sev_firmware_shutdown(struct sev_device *sev)
 {
+	int error;
+
 	sev_platform_shutdown(NULL);
 
 	if (sev_es_tmr) {
@@ -1301,6 +1545,13 @@ static void sev_firmware_shutdown(struct sev_device *sev)
 			   get_order(NV_LENGTH));
 		sev_init_ex_buffer = NULL;
 	}
+
+	if (snp_range_list) {
+		kfree(snp_range_list);
+		snp_range_list = NULL;
+	}
+
+	sev_snp_shutdown(&error);
 }
 
 void sev_dev_destroy(struct psp_device *psp)
@@ -1356,24 +1607,15 @@ void sev_pci_init(void)
 		}
 	}
 
-	/* Obtain the TMR memory area for SEV-ES use */
-	sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
-	if (sev_es_tmr)
-		/* Must flush the cache before giving it to the firmware */
-		clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE);
-	else
-		dev_warn(sev->dev,
-			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
-
-	if (!psp_init_on_probe)
-		return;
-
 	/* Initialize the platform */
-	rc = sev_platform_init(&error);
+	rc = sev_platform_init_on_probe(&error);
 	if (rc)
 		dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n",
 			error, rc);
 
+	dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_initialized ?
+		"-SNP" : "", sev->api_major, sev->api_minor, sev->build);
+
 	return;
 
 err:
diff --git a/drivers/crypto/ccp/sev-dev.h b/drivers/crypto/ccp/sev-dev.h
index 778c95155e74..85506325051a 100644
--- a/drivers/crypto/ccp/sev-dev.h
+++ b/drivers/crypto/ccp/sev-dev.h
@@ -52,6 +52,8 @@ struct sev_device {
 	u8 build;
 
 	void *cmd_buf;
+
+	bool snp_initialized;
 };
 
 int sev_dev_init(struct psp_device *psp);
