nvme: Add NVM Express driver support

NVM Express (NVMe) is a register level interface that allows host
software to communicate with a non-volatile memory subsystem. This
interface is optimized for enterprise and client solid state drives,
typically attached to the PCI express interface.

This adds a U-Boot driver support of devices that follow the NVMe
standard [1] and supports basic read/write operations.

Tested with a 400GB Intel SSD 750 series NVMe card with controller
id 8086:0953.

[1] http://www.nvmexpress.org/resources/specifications/

Signed-off-by: Zhikang Zhang <zhikang.zhang@nxp.com>
Signed-off-by: Wenbin Song <wenbin.song@nxp.com>
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/nvme/nvme.h b/drivers/nvme/nvme.h
new file mode 100644
index 0000000..b7fdd0b
--- /dev/null
+++ b/drivers/nvme/nvme.h
@@ -0,0 +1,717 @@
+/*
+ * Copyright (C) 2017 NXP Semiconductors
+ * Copyright (C) 2017 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __DRIVER_NVME_H__
+#define __DRIVER_NVME_H__
+
+#include <asm/io.h>
+
+struct nvme_id_power_state {
+	__le16			max_power;	/* centiwatts */
+	__u8			rsvd2;
+	__u8			flags;
+	__le32			entry_lat;	/* microseconds */
+	__le32			exit_lat;	/* microseconds */
+	__u8			read_tput;
+	__u8			read_lat;
+	__u8			write_tput;
+	__u8			write_lat;
+	__le16			idle_power;
+	__u8			idle_scale;
+	__u8			rsvd19;
+	__le16			active_power;
+	__u8			active_work_scale;
+	__u8			rsvd23[9];
+};
+
+enum {
+	NVME_PS_FLAGS_MAX_POWER_SCALE	= 1 << 0,
+	NVME_PS_FLAGS_NON_OP_STATE	= 1 << 1,
+};
+
+struct nvme_id_ctrl {
+	__le16			vid;
+	__le16			ssvid;
+	char			sn[20];
+	char			mn[40];
+	char			fr[8];
+	__u8			rab;
+	__u8			ieee[3];
+	__u8			mic;
+	__u8			mdts;
+	__u16			cntlid;
+	__u32			ver;
+	__u8			rsvd84[172];
+	__le16			oacs;
+	__u8			acl;
+	__u8			aerl;
+	__u8			frmw;
+	__u8			lpa;
+	__u8			elpe;
+	__u8			npss;
+	__u8			avscc;
+	__u8			apsta;
+	__le16			wctemp;
+	__le16			cctemp;
+	__u8			rsvd270[242];
+	__u8			sqes;
+	__u8			cqes;
+	__u8			rsvd514[2];
+	__le32			nn;
+	__le16			oncs;
+	__le16			fuses;
+	__u8			fna;
+	__u8			vwc;
+	__le16			awun;
+	__le16			awupf;
+	__u8			nvscc;
+	__u8			rsvd531;
+	__le16			acwu;
+	__u8			rsvd534[2];
+	__le32			sgls;
+	__u8			rsvd540[1508];
+	struct nvme_id_power_state	psd[32];
+	__u8			vs[1024];
+};
+
+enum {
+	NVME_CTRL_ONCS_COMPARE			= 1 << 0,
+	NVME_CTRL_ONCS_WRITE_UNCORRECTABLE	= 1 << 1,
+	NVME_CTRL_ONCS_DSM			= 1 << 2,
+	NVME_CTRL_VWC_PRESENT			= 1 << 0,
+};
+
+struct nvme_lbaf {
+	__le16			ms;
+	__u8			ds;
+	__u8			rp;
+};
+
+struct nvme_id_ns {
+	__le64			nsze;
+	__le64			ncap;
+	__le64			nuse;
+	__u8			nsfeat;
+	__u8			nlbaf;
+	__u8			flbas;
+	__u8			mc;
+	__u8			dpc;
+	__u8			dps;
+	__u8			nmic;
+	__u8			rescap;
+	__u8			fpi;
+	__u8			rsvd33;
+	__le16			nawun;
+	__le16			nawupf;
+	__le16			nacwu;
+	__le16			nabsn;
+	__le16			nabo;
+	__le16			nabspf;
+	__u16			rsvd46;
+	__le64			nvmcap[2];
+	__u8			rsvd64[40];
+	__u8			nguid[16];
+	__u8			eui64[8];
+	struct nvme_lbaf	lbaf[16];
+	__u8			rsvd192[192];
+	__u8			vs[3712];
+};
+
+enum {
+	NVME_NS_FEAT_THIN	= 1 << 0,
+	NVME_NS_FLBAS_LBA_MASK	= 0xf,
+	NVME_NS_FLBAS_META_EXT	= 0x10,
+	NVME_LBAF_RP_BEST	= 0,
+	NVME_LBAF_RP_BETTER	= 1,
+	NVME_LBAF_RP_GOOD	= 2,
+	NVME_LBAF_RP_DEGRADED	= 3,
+	NVME_NS_DPC_PI_LAST	= 1 << 4,
+	NVME_NS_DPC_PI_FIRST	= 1 << 3,
+	NVME_NS_DPC_PI_TYPE3	= 1 << 2,
+	NVME_NS_DPC_PI_TYPE2	= 1 << 1,
+	NVME_NS_DPC_PI_TYPE1	= 1 << 0,
+	NVME_NS_DPS_PI_FIRST	= 1 << 3,
+	NVME_NS_DPS_PI_MASK	= 0x7,
+	NVME_NS_DPS_PI_TYPE1	= 1,
+	NVME_NS_DPS_PI_TYPE2	= 2,
+	NVME_NS_DPS_PI_TYPE3	= 3,
+};
+
+struct nvme_smart_log {
+	__u8			critical_warning;
+	__u8			temperature[2];
+	__u8			avail_spare;
+	__u8			spare_thresh;
+	__u8			percent_used;
+	__u8			rsvd6[26];
+	__u8			data_units_read[16];
+	__u8			data_units_written[16];
+	__u8			host_reads[16];
+	__u8			host_writes[16];
+	__u8			ctrl_busy_time[16];
+	__u8			power_cycles[16];
+	__u8			power_on_hours[16];
+	__u8			unsafe_shutdowns[16];
+	__u8			media_errors[16];
+	__u8			num_err_log_entries[16];
+	__le32			warning_temp_time;
+	__le32			critical_comp_time;
+	__le16			temp_sensor[8];
+	__u8			rsvd216[296];
+};
+
+enum {
+	NVME_SMART_CRIT_SPARE		= 1 << 0,
+	NVME_SMART_CRIT_TEMPERATURE	= 1 << 1,
+	NVME_SMART_CRIT_RELIABILITY	= 1 << 2,
+	NVME_SMART_CRIT_MEDIA		= 1 << 3,
+	NVME_SMART_CRIT_VOLATILE_MEMORY	= 1 << 4,
+};
+
+struct nvme_lba_range_type {
+	__u8			type;
+	__u8			attributes;
+	__u8			rsvd2[14];
+	__u64			slba;
+	__u64			nlb;
+	__u8			guid[16];
+	__u8			rsvd48[16];
+};
+
+enum {
+	NVME_LBART_TYPE_FS	= 0x01,
+	NVME_LBART_TYPE_RAID	= 0x02,
+	NVME_LBART_TYPE_CACHE	= 0x03,
+	NVME_LBART_TYPE_SWAP	= 0x04,
+
+	NVME_LBART_ATTRIB_TEMP	= 1 << 0,
+	NVME_LBART_ATTRIB_HIDE	= 1 << 1,
+};
+
+struct nvme_reservation_status {
+	__le32	gen;
+	__u8	rtype;
+	__u8	regctl[2];
+	__u8	resv5[2];
+	__u8	ptpls;
+	__u8	resv10[13];
+	struct {
+		__le16	cntlid;
+		__u8	rcsts;
+		__u8	resv3[5];
+		__le64	hostid;
+		__le64	rkey;
+	} regctl_ds[];
+};
+
+/* I/O commands */
+
+enum nvme_opcode {
+	nvme_cmd_flush		= 0x00,
+	nvme_cmd_write		= 0x01,
+	nvme_cmd_read		= 0x02,
+	nvme_cmd_write_uncor	= 0x04,
+	nvme_cmd_compare	= 0x05,
+	nvme_cmd_write_zeroes	= 0x08,
+	nvme_cmd_dsm		= 0x09,
+	nvme_cmd_resv_register	= 0x0d,
+	nvme_cmd_resv_report	= 0x0e,
+	nvme_cmd_resv_acquire	= 0x11,
+	nvme_cmd_resv_release	= 0x15,
+};
+
+struct nvme_common_command {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__le32			cdw2[2];
+	__le64			metadata;
+	__le64			prp1;
+	__le64			prp2;
+	__le32			cdw10[6];
+};
+
+struct nvme_rw_command {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd2;
+	__le64			metadata;
+	__le64			prp1;
+	__le64			prp2;
+	__le64			slba;
+	__le16			length;
+	__le16			control;
+	__le32			dsmgmt;
+	__le32			reftag;
+	__le16			apptag;
+	__le16			appmask;
+};
+
+enum {
+	NVME_RW_LR			= 1 << 15,
+	NVME_RW_FUA			= 1 << 14,
+	NVME_RW_DSM_FREQ_UNSPEC		= 0,
+	NVME_RW_DSM_FREQ_TYPICAL	= 1,
+	NVME_RW_DSM_FREQ_RARE		= 2,
+	NVME_RW_DSM_FREQ_READS		= 3,
+	NVME_RW_DSM_FREQ_WRITES		= 4,
+	NVME_RW_DSM_FREQ_RW		= 5,
+	NVME_RW_DSM_FREQ_ONCE		= 6,
+	NVME_RW_DSM_FREQ_PREFETCH	= 7,
+	NVME_RW_DSM_FREQ_TEMP		= 8,
+	NVME_RW_DSM_LATENCY_NONE	= 0 << 4,
+	NVME_RW_DSM_LATENCY_IDLE	= 1 << 4,
+	NVME_RW_DSM_LATENCY_NORM	= 2 << 4,
+	NVME_RW_DSM_LATENCY_LOW		= 3 << 4,
+	NVME_RW_DSM_SEQ_REQ		= 1 << 6,
+	NVME_RW_DSM_COMPRESSED		= 1 << 7,
+	NVME_RW_PRINFO_PRCHK_REF	= 1 << 10,
+	NVME_RW_PRINFO_PRCHK_APP	= 1 << 11,
+	NVME_RW_PRINFO_PRCHK_GUARD	= 1 << 12,
+	NVME_RW_PRINFO_PRACT		= 1 << 13,
+};
+
+struct nvme_dsm_cmd {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd2[2];
+	__le64			prp1;
+	__le64			prp2;
+	__le32			nr;
+	__le32			attributes;
+	__u32			rsvd12[4];
+};
+
+enum {
+	NVME_DSMGMT_IDR		= 1 << 0,
+	NVME_DSMGMT_IDW		= 1 << 1,
+	NVME_DSMGMT_AD		= 1 << 2,
+};
+
+struct nvme_dsm_range {
+	__le32			cattr;
+	__le32			nlb;
+	__le64			slba;
+};
+
+/* Admin commands */
+
+enum nvme_admin_opcode {
+	nvme_admin_delete_sq		= 0x00,
+	nvme_admin_create_sq		= 0x01,
+	nvme_admin_get_log_page		= 0x02,
+	nvme_admin_delete_cq		= 0x04,
+	nvme_admin_create_cq		= 0x05,
+	nvme_admin_identify		= 0x06,
+	nvme_admin_abort_cmd		= 0x08,
+	nvme_admin_set_features		= 0x09,
+	nvme_admin_get_features		= 0x0a,
+	nvme_admin_async_event		= 0x0c,
+	nvme_admin_activate_fw		= 0x10,
+	nvme_admin_download_fw		= 0x11,
+	nvme_admin_format_nvm		= 0x80,
+	nvme_admin_security_send	= 0x81,
+	nvme_admin_security_recv	= 0x82,
+};
+
+enum {
+	NVME_QUEUE_PHYS_CONTIG	= (1 << 0),
+	NVME_CQ_IRQ_ENABLED	= (1 << 1),
+	NVME_SQ_PRIO_URGENT	= (0 << 1),
+	NVME_SQ_PRIO_HIGH	= (1 << 1),
+	NVME_SQ_PRIO_MEDIUM	= (2 << 1),
+	NVME_SQ_PRIO_LOW	= (3 << 1),
+	NVME_FEAT_ARBITRATION	= 0x01,
+	NVME_FEAT_POWER_MGMT	= 0x02,
+	NVME_FEAT_LBA_RANGE	= 0x03,
+	NVME_FEAT_TEMP_THRESH	= 0x04,
+	NVME_FEAT_ERR_RECOVERY	= 0x05,
+	NVME_FEAT_VOLATILE_WC	= 0x06,
+	NVME_FEAT_NUM_QUEUES	= 0x07,
+	NVME_FEAT_IRQ_COALESCE	= 0x08,
+	NVME_FEAT_IRQ_CONFIG	= 0x09,
+	NVME_FEAT_WRITE_ATOMIC	= 0x0a,
+	NVME_FEAT_ASYNC_EVENT	= 0x0b,
+	NVME_FEAT_AUTO_PST	= 0x0c,
+	NVME_FEAT_SW_PROGRESS	= 0x80,
+	NVME_FEAT_HOST_ID	= 0x81,
+	NVME_FEAT_RESV_MASK	= 0x82,
+	NVME_FEAT_RESV_PERSIST	= 0x83,
+	NVME_LOG_ERROR		= 0x01,
+	NVME_LOG_SMART		= 0x02,
+	NVME_LOG_FW_SLOT	= 0x03,
+	NVME_LOG_RESERVATION	= 0x80,
+	NVME_FWACT_REPL		= (0 << 3),
+	NVME_FWACT_REPL_ACTV	= (1 << 3),
+	NVME_FWACT_ACTV		= (2 << 3),
+};
+
+struct nvme_identify {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd2[2];
+	__le64			prp1;
+	__le64			prp2;
+	__le32			cns;
+	__u32			rsvd11[5];
+};
+
+struct nvme_features {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd2[2];
+	__le64			prp1;
+	__le64			prp2;
+	__le32			fid;
+	__le32			dword11;
+	__u32			rsvd12[4];
+};
+
+struct nvme_create_cq {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[5];
+	__le64			prp1;
+	__u64			rsvd8;
+	__le16			cqid;
+	__le16			qsize;
+	__le16			cq_flags;
+	__le16			irq_vector;
+	__u32			rsvd12[4];
+};
+
+struct nvme_create_sq {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[5];
+	__le64			prp1;
+	__u64			rsvd8;
+	__le16			sqid;
+	__le16			qsize;
+	__le16			sq_flags;
+	__le16			cqid;
+	__u32			rsvd12[4];
+};
+
+struct nvme_delete_queue {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[9];
+	__le16			qid;
+	__u16			rsvd10;
+	__u32			rsvd11[5];
+};
+
+struct nvme_abort_cmd {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[9];
+	__le16			sqid;
+	__u16			cid;
+	__u32			rsvd11[5];
+};
+
+struct nvme_download_firmware {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__u32			rsvd1[5];
+	__le64			prp1;
+	__le64			prp2;
+	__le32			numd;
+	__le32			offset;
+	__u32			rsvd12[4];
+};
+
+struct nvme_format_cmd {
+	__u8			opcode;
+	__u8			flags;
+	__u16			command_id;
+	__le32			nsid;
+	__u64			rsvd2[4];
+	__le32			cdw10;
+	__u32			rsvd11[5];
+};
+
+struct nvme_command {
+	union {
+		struct nvme_common_command common;
+		struct nvme_rw_command rw;
+		struct nvme_identify identify;
+		struct nvme_features features;
+		struct nvme_create_cq create_cq;
+		struct nvme_create_sq create_sq;
+		struct nvme_delete_queue delete_queue;
+		struct nvme_download_firmware dlfw;
+		struct nvme_format_cmd format;
+		struct nvme_dsm_cmd dsm;
+		struct nvme_abort_cmd abort;
+	};
+};
+
+enum {
+	NVME_SC_SUCCESS			= 0x0,
+	NVME_SC_INVALID_OPCODE		= 0x1,
+	NVME_SC_INVALID_FIELD		= 0x2,
+	NVME_SC_CMDID_CONFLICT		= 0x3,
+	NVME_SC_DATA_XFER_ERROR		= 0x4,
+	NVME_SC_POWER_LOSS		= 0x5,
+	NVME_SC_INTERNAL		= 0x6,
+	NVME_SC_ABORT_REQ		= 0x7,
+	NVME_SC_ABORT_QUEUE		= 0x8,
+	NVME_SC_FUSED_FAIL		= 0x9,
+	NVME_SC_FUSED_MISSING		= 0xa,
+	NVME_SC_INVALID_NS		= 0xb,
+	NVME_SC_CMD_SEQ_ERROR		= 0xc,
+	NVME_SC_SGL_INVALID_LAST	= 0xd,
+	NVME_SC_SGL_INVALID_COUNT	= 0xe,
+	NVME_SC_SGL_INVALID_DATA	= 0xf,
+	NVME_SC_SGL_INVALID_METADATA	= 0x10,
+	NVME_SC_SGL_INVALID_TYPE	= 0x11,
+	NVME_SC_LBA_RANGE		= 0x80,
+	NVME_SC_CAP_EXCEEDED		= 0x81,
+	NVME_SC_NS_NOT_READY		= 0x82,
+	NVME_SC_RESERVATION_CONFLICT	= 0x83,
+	NVME_SC_CQ_INVALID		= 0x100,
+	NVME_SC_QID_INVALID		= 0x101,
+	NVME_SC_QUEUE_SIZE		= 0x102,
+	NVME_SC_ABORT_LIMIT		= 0x103,
+	NVME_SC_ABORT_MISSING		= 0x104,
+	NVME_SC_ASYNC_LIMIT		= 0x105,
+	NVME_SC_FIRMWARE_SLOT		= 0x106,
+	NVME_SC_FIRMWARE_IMAGE		= 0x107,
+	NVME_SC_INVALID_VECTOR		= 0x108,
+	NVME_SC_INVALID_LOG_PAGE	= 0x109,
+	NVME_SC_INVALID_FORMAT		= 0x10a,
+	NVME_SC_FIRMWARE_NEEDS_RESET	= 0x10b,
+	NVME_SC_INVALID_QUEUE		= 0x10c,
+	NVME_SC_FEATURE_NOT_SAVEABLE	= 0x10d,
+	NVME_SC_FEATURE_NOT_CHANGEABLE	= 0x10e,
+	NVME_SC_FEATURE_NOT_PER_NS	= 0x10f,
+	NVME_SC_FW_NEEDS_RESET_SUBSYS	= 0x110,
+	NVME_SC_BAD_ATTRIBUTES		= 0x180,
+	NVME_SC_INVALID_PI		= 0x181,
+	NVME_SC_READ_ONLY		= 0x182,
+	NVME_SC_WRITE_FAULT		= 0x280,
+	NVME_SC_READ_ERROR		= 0x281,
+	NVME_SC_GUARD_CHECK		= 0x282,
+	NVME_SC_APPTAG_CHECK		= 0x283,
+	NVME_SC_REFTAG_CHECK		= 0x284,
+	NVME_SC_COMPARE_FAILED		= 0x285,
+	NVME_SC_ACCESS_DENIED		= 0x286,
+	NVME_SC_DNR			= 0x4000,
+};
+
+struct nvme_completion {
+	__le32	result;		/* Used by admin commands to return data */
+	__u32	rsvd;
+	__le16	sq_head;	/* how much of this queue may be reclaimed */
+	__le16	sq_id;		/* submission queue that generated this entry */
+	__u16	command_id;	/* of the command which completed */
+	__le16	status;		/* did the command fail, and if so, why? */
+};
+
+struct nvme_user_io {
+	__u8	opcode;
+	__u8	flags;
+	__u16	control;
+	__u16	nblocks;
+	__u16	rsvd;
+	__u64	metadata;
+	__u64	addr;
+	__u64	slba;
+	__u32	dsmgmt;
+	__u32	reftag;
+	__u16	apptag;
+	__u16	appmask;
+};
+
+struct nvme_passthru_cmd {
+	__u8	opcode;
+	__u8	flags;
+	__u16	rsvd1;
+	__u32	nsid;
+	__u32	cdw2;
+	__u32	cdw3;
+	__u64	metadata;
+	__u64	addr;
+	__u32	metadata_len;
+	__u32	data_len;
+	__u32	cdw10;
+	__u32	cdw11;
+	__u32	cdw12;
+	__u32	cdw13;
+	__u32	cdw14;
+	__u32	cdw15;
+	__u32	timeout_ms;
+	__u32	result;
+};
+
+/*
+ * Registers should always be accessed with double word or quad word
+ * accesses. Registers with 64-bit address pointers should be written
+ * to with dword accesses by writing the low dword first (ptr[0]),
+ * then the high dword (ptr[1]) second.
+ */
+static inline u64 nvme_readq(__le64 volatile *regs)
+{
+#if BITS_PER_LONG == 64
+	return readq(regs);
+#else
+	__u32 *ptr = (__u32 *)regs;
+	u64 val_lo = readl(ptr);
+	u64 val_hi = readl(ptr + 1);
+
+	return val_lo + (val_hi << 32);
+#endif
+}
+
+static inline void nvme_writeq(const u64 val, __le64 volatile *regs)
+{
+#if BITS_PER_LONG == 64
+	writeq(val, regs);
+#else
+	__u32 *ptr = (__u32 *)regs;
+	u32 val_lo = lower_32_bits(val);
+	u32 val_hi = upper_32_bits(val);
+	writel(val_lo, ptr);
+	writel(val_hi, ptr + 1);
+#endif
+}
+
+struct nvme_bar {
+	__u64 cap;	/* Controller Capabilities */
+	__u32 vs;	/* Version */
+	__u32 intms;	/* Interrupt Mask Set */
+	__u32 intmc;	/* Interrupt Mask Clear */
+	__u32 cc;	/* Controller Configuration */
+	__u32 rsvd1;	/* Reserved */
+	__u32 csts;	/* Controller Status */
+	__u32 rsvd2;	/* Reserved */
+	__u32 aqa;	/* Admin Queue Attributes */
+	__u64 asq;	/* Admin SQ Base Address */
+	__u64 acq;	/* Admin CQ Base Address */
+};
+
+#define NVME_CAP_MQES(cap)	((cap) & 0xffff)
+#define NVME_CAP_TIMEOUT(cap)	(((cap) >> 24) & 0xff)
+#define NVME_CAP_STRIDE(cap)	(((cap) >> 32) & 0xf)
+#define NVME_CAP_MPSMIN(cap)	(((cap) >> 48) & 0xf)
+#define NVME_CAP_MPSMAX(cap)	(((cap) >> 52) & 0xf)
+
+#define NVME_VS(major, minor)	(((major) << 16) | ((minor) << 8))
+
+enum {
+	NVME_CC_ENABLE		= 1 << 0,
+	NVME_CC_CSS_NVM		= 0 << 4,
+	NVME_CC_MPS_SHIFT	= 7,
+	NVME_CC_ARB_RR		= 0 << 11,
+	NVME_CC_ARB_WRRU	= 1 << 11,
+	NVME_CC_ARB_VS		= 7 << 11,
+	NVME_CC_SHN_NONE	= 0 << 14,
+	NVME_CC_SHN_NORMAL	= 1 << 14,
+	NVME_CC_SHN_ABRUPT	= 2 << 14,
+	NVME_CC_SHN_MASK	= 3 << 14,
+	NVME_CC_IOSQES		= 6 << 16,
+	NVME_CC_IOCQES		= 4 << 20,
+	NVME_CSTS_RDY		= 1 << 0,
+	NVME_CSTS_CFS		= 1 << 1,
+	NVME_CSTS_SHST_NORMAL	= 0 << 2,
+	NVME_CSTS_SHST_OCCUR	= 1 << 2,
+	NVME_CSTS_SHST_CMPLT	= 2 << 2,
+	NVME_CSTS_SHST_MASK	= 3 << 2,
+};
+
+/* Represents an NVM Express device. Each nvme_dev is a PCI function. */
+struct nvme_dev {
+	struct list_head node;
+	struct nvme_queue **queues;
+	u32 __iomem *dbs;
+	unsigned int cardnum;
+	struct udevice *pdev;
+	pci_dev_t pci_dev;
+	int instance;
+	uint8_t *hw_addr;
+	unsigned queue_count;
+	unsigned online_queues;
+	unsigned max_qid;
+	int q_depth;
+	u32 db_stride;
+	u32 ctrl_config;
+	struct nvme_bar __iomem *bar;
+	struct list_head namespaces;
+	const char *name;
+	char serial[20];
+	char model[40];
+	char firmware_rev[8];
+	u32 max_transfer_shift;
+	u32 stripe_size;
+	u32 page_size;
+	u16 oncs;
+	u16 abort_limit;
+	u8 event_limit;
+	u8 vwc;
+	u64 *prp_pool;
+	u32 prp_entry_num;
+	u32 nn;
+	u32 blk_dev_start;
+};
+
+struct nvme_info {
+	int ns_num;	/*the number of nvme namespaces*/
+	int ndev_num;	/*the number of nvme devices*/
+	struct list_head dev_list;
+};
+
+/*
+ * The nvme_iod describes the data in an I/O, including the list of PRP
+ * entries.  You can't see it in this data structure because C doesn't let
+ * me express that.  Use nvme_alloc_iod to ensure there's enough space
+ * allocated to store the PRP list.
+ */
+struct nvme_iod {
+	unsigned long private;	/* For the use of the submitter of the I/O */
+	int npages;		/* In the PRP list. 0 means small pool in use */
+	int offset;		/* Of PRP list */
+	int nents;		/* Used in scatterlist */
+	int length;		/* Of data, in bytes */
+	dma_addr_t first_dma;
+};
+
+/*
+ * An NVM Express namespace is equivalent to a SCSI LUN.
+ * Each namespace is operated as an independent "device".
+ */
+struct nvme_ns {
+	struct list_head list;
+	struct nvme_dev *dev;
+	unsigned ns_id;
+	int devnum;
+	int lba_shift;
+	u16 ms;
+	u8 flbas;
+	u8 pi_type;
+	u64 mode_select_num_blocks;
+	u32 mode_select_block_len;
+};
+
+extern struct nvme_info *nvme_info;
+
+#endif /* __DRIVER_NVME_H__ */