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>

9 files changed, 1753 insertions, 0 deletions

diff --git a/doc/README.nvme b/doc/README.nvme
new file mode 100644
index 0000000..d2b917d
--- /dev/null
+++ b/doc/README.nvme
@@ -0,0 +1,42 @@
+#
+# Copyright (C) 2017 NXP Semiconductors
+# Copyright (C) 2017 Bin Meng <bmeng.cn@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+What is NVMe
+============
+
+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. It is a scalable host controller interface designed to
+address the needs of enterprise and client systems that utilize PCI express
+based solid state drives (SSD). The interface provides optimized command
+submission and completion paths. It includes support for parallel operation by
+supporting up to 64K I/O queues with up to 64K commands per I/O queue.
+
+The device is comprised of some number of controllers, where each controller
+is comprised of some number of namespaces, where each namespace is comprised
+of some number of logical blocks. A namespace is a quantity of non-volatile
+memory that is formatted into logical blocks. An NVMe namespace is equivalent
+to a SCSI LUN. Each namespace is operated as an independent "device".
+
+How it works
+------------
+There is an NVMe uclass driver (driver name "nvme"), an NVMe host controller
+driver (driver name "nvme") and an NVMe namespace block driver (driver name
+"nvme-blk"). The host controller driver is supposed to probe the hardware and
+do necessary initialization to put the controller into a ready state at which
+it is able to scan all available namespaces attached to it. Scanning namespace
+is triggered by the NVMe uclass driver and the actual work is done in the NVMe
+namespace block driver.
+
+Status
+------
+It only support basic block read/write functions in the NVMe driver.
+
+Config options
+--------------
+CONFIG_NVME	Enable NVMe device support
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 2e03133..613e602 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -50,6 +50,8 @@ source "drivers/mtd/Kconfig"
 
 source "drivers/net/Kconfig"
 
+source "drivers/nvme/Kconfig"
+
 source "drivers/pci/Kconfig"
 
 source "drivers/pcmcia/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index e4a9cb4..0cbfa5d 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -78,6 +78,7 @@ obj-y += firmware/
 obj-$(CONFIG_FPGA) += fpga/
 obj-y += misc/
 obj-$(CONFIG_MMC) += mmc/
+obj-$(CONFIG_NVME) += nvme/
 obj-y += pcmcia/
 obj-y += dfu/
 obj-$(CONFIG_X86) += pch/
diff --git a/drivers/nvme/Kconfig b/drivers/nvme/Kconfig
new file mode 100644
index 0000000..cad8dbc
--- /dev/null
+++ b/drivers/nvme/Kconfig
@@ -0,0 +1,12 @@
+#
+# Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+config NVME
+	bool "NVM Express device support"
+	depends on BLK && PCI
+	help
+	  This option enables support for NVM Express devices.
+	  It supports basic functions of NVMe (read/write).
diff --git a/drivers/nvme/Makefile b/drivers/nvme/Makefile
new file mode 100644
index 0000000..7bd9fa4
--- /dev/null
+++ b/drivers/nvme/Makefile
@@ -0,0 +1,7 @@
+#
+# Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += nvme-uclass.o nvme.o
diff --git a/drivers/nvme/nvme-uclass.c b/drivers/nvme/nvme-uclass.c
new file mode 100644
index 0000000..0895bc9
--- /dev/null
+++ b/drivers/nvme/nvme-uclass.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2017 NXP Semiconductors
+ * Copyright (C) 2017 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <dm.h>
+#include <dm/device.h>
+#include "nvme.h"
+
+static int nvme_info_init(struct uclass *uc)
+{
+	struct nvme_info *info = (struct nvme_info *)uc->priv;
+
+	info->ns_num = 0;
+	info->ndev_num = 0;
+	INIT_LIST_HEAD(&info->dev_list);
+	nvme_info = info;
+
+	return 0;
+}
+
+static int nvme_uclass_post_probe(struct udevice *udev)
+{
+	char name[20];
+	char *str;
+	struct udevice *ns_udev;
+	int i, ret;
+	struct nvme_dev *ndev = dev_get_priv(udev);
+
+	/* Create a blk device for each namespace */
+	for (i = 0; i < ndev->nn; i++) {
+		sprintf(name, "nvme-blk#%d", nvme_info->ns_num);
+		str = strdup(name);
+		if (!str)
+			return -ENOMEM;
+
+		/* The real blksz and size will be set by nvme_blk_probe() */
+		ret = blk_create_device(udev, "nvme-blk", str, IF_TYPE_NVME,
+					nvme_info->ns_num++, 512, 0, &ns_udev);
+		if (ret) {
+			free(str);
+			nvme_info->ns_num--;
+
+			return ret;
+		}
+		device_set_name_alloced(ns_udev);
+	}
+
+	return 0;
+}
+
+UCLASS_DRIVER(nvme) = {
+	.name	= "nvme",
+	.id	= UCLASS_NVME,
+	.init	= nvme_info_init,
+	.post_probe = nvme_uclass_post_probe,
+	.priv_auto_alloc_size = sizeof(struct nvme_info),
+};
diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c
new file mode 100644
index 0000000..a60682a
--- /dev/null
+++ b/drivers/nvme/nvme.c
@@ -0,0 +1,839 @@
+/*
+ * Copyright (C) 2017 NXP Semiconductors
+ * Copyright (C) 2017 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <memalign.h>
+#include <pci.h>
+#include <dm/device-internal.h>
+#include "nvme.h"
+
+struct nvme_info *nvme_info;
+
+#define NVME_Q_DEPTH		2
+#define NVME_AQ_DEPTH		2
+#define NVME_SQ_SIZE(depth)	(depth * sizeof(struct nvme_command))
+#define NVME_CQ_SIZE(depth)	(depth * sizeof(struct nvme_completion))
+#define ADMIN_TIMEOUT		60
+#define IO_TIMEOUT		30
+#define MAX_PRP_POOL		512
+
+/*
+ * An NVM Express queue. Each device has at least two (one for admin
+ * commands and one for I/O commands).
+ */
+struct nvme_queue {
+	struct nvme_dev *dev;
+	struct nvme_command *sq_cmds;
+	struct nvme_completion *cqes;
+	wait_queue_head_t sq_full;
+	u32 __iomem *q_db;
+	u16 q_depth;
+	s16 cq_vector;
+	u16 sq_head;
+	u16 sq_tail;
+	u16 cq_head;
+	u16 qid;
+	u8 cq_phase;
+	u8 cqe_seen;
+	unsigned long cmdid_data[];
+};
+
+static int nvme_wait_ready(struct nvme_dev *dev, bool enabled)
+{
+	u32 bit = enabled ? NVME_CSTS_RDY : 0;
+
+	while ((readl(&dev->bar->csts) & NVME_CSTS_RDY) != bit)
+		udelay(10000);
+
+	return 0;
+}
+
+static int nvme_setup_prps(struct nvme_dev *dev, u64 *prp2,
+			   int total_len, u64 dma_addr)
+{
+	u32 page_size = dev->page_size;
+	int offset = dma_addr & (page_size - 1);
+	u64 *prp_pool;
+	int length = total_len;
+	int i, nprps;
+	length -= (page_size - offset);
+
+	if (length <= 0) {
+		*prp2 = 0;
+		return 0;
+	}
+
+	if (length)
+		dma_addr += (page_size - offset);
+
+	if (length <= page_size) {
+		*prp2 = dma_addr;
+		return 0;
+	}
+
+	nprps = DIV_ROUND_UP(length, page_size);
+
+	if (nprps > dev->prp_entry_num) {
+		free(dev->prp_pool);
+		dev->prp_pool = malloc(nprps << 3);
+		if (!dev->prp_pool) {
+			printf("Error: malloc prp_pool fail\n");
+			return -ENOMEM;
+		}
+		dev->prp_entry_num = nprps;
+	}
+
+	prp_pool = dev->prp_pool;
+	i = 0;
+	while (nprps) {
+		if (i == ((page_size >> 3) - 1)) {
+			*(prp_pool + i) = cpu_to_le64((ulong)prp_pool +
+					page_size);
+			i = 0;
+			prp_pool += page_size;
+		}
+		*(prp_pool + i++) = cpu_to_le64(dma_addr);
+		dma_addr += page_size;
+		nprps--;
+	}
+	*prp2 = (ulong)dev->prp_pool;
+
+	return 0;
+}
+
+static __le16 nvme_get_cmd_id(void)
+{
+	static unsigned short cmdid;
+
+	return cpu_to_le16((cmdid < USHRT_MAX) ? cmdid++ : 0);
+}
+
+static u16 nvme_read_completion_status(struct nvme_queue *nvmeq, u16 index)
+{
+	u64 start = (ulong)&nvmeq->cqes[index];
+	u64 stop = start + sizeof(struct nvme_completion);
+
+	invalidate_dcache_range(start, stop);
+
+	return le16_to_cpu(readw(&(nvmeq->cqes[index].status)));
+}
+
+/**
+ * nvme_submit_cmd() - copy a command into a queue and ring the doorbell
+ *
+ * @nvmeq:	The queue to use
+ * @cmd:	The command to send
+ */
+static void nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
+{
+	u16 tail = nvmeq->sq_tail;
+
+	memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
+	flush_dcache_range((ulong)&nvmeq->sq_cmds[tail],
+			   (ulong)&nvmeq->sq_cmds[tail] + sizeof(*cmd));
+
+	if (++tail == nvmeq->q_depth)
+		tail = 0;
+	writel(tail, nvmeq->q_db);
+	nvmeq->sq_tail = tail;
+}
+
+static int nvme_submit_sync_cmd(struct nvme_queue *nvmeq,
+				struct nvme_command *cmd,
+				u32 *result, unsigned timeout)
+{
+	u16 head = nvmeq->cq_head;
+	u16 phase = nvmeq->cq_phase;
+	u16 status;
+	ulong start_time;
+	ulong timeout_us = timeout * 100000;
+
+	cmd->common.command_id = nvme_get_cmd_id();
+	nvme_submit_cmd(nvmeq, cmd);
+
+	start_time = timer_get_us();
+
+	for (;;) {
+		status = nvme_read_completion_status(nvmeq, head);
+		if ((status & 0x01) == phase)
+			break;
+		if (timeout_us > 0 && (timer_get_us() - start_time)
+		    >= timeout_us)
+			return -ETIMEDOUT;
+	}
+
+	status >>= 1;
+	if (status) {
+		printf("ERROR: status = %x, phase = %d, head = %d\n",
+		       status, phase, head);
+		status = 0;
+		if (++head == nvmeq->q_depth) {
+			head = 0;
+			phase = !phase;
+		}
+		writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
+		nvmeq->cq_head = head;
+		nvmeq->cq_phase = phase;
+
+		return -EIO;
+	}
+
+	if (result)
+		*result = le32_to_cpu(readl(&(nvmeq->cqes[head].result)));
+
+	if (++head == nvmeq->q_depth) {
+		head = 0;
+		phase = !phase;
+	}
+	writel(head, nvmeq->q_db + nvmeq->dev->db_stride);
+	nvmeq->cq_head = head;
+	nvmeq->cq_phase = phase;
+
+	return status;
+}
+
+static int nvme_submit_admin_cmd(struct nvme_dev *dev, struct nvme_command *cmd,
+				 u32 *result)
+{
+	return nvme_submit_sync_cmd(dev->queues[0], cmd, result, ADMIN_TIMEOUT);
+}
+
+static struct nvme_queue *nvme_alloc_queue(struct nvme_dev *dev,
+					   int qid, int depth)
+{
+	struct nvme_queue *nvmeq = malloc(sizeof(*nvmeq));
+	if (!nvmeq)
+		return NULL;
+	memset(nvmeq, 0, sizeof(*nvmeq));
+
+	nvmeq->cqes = (void *)memalign(4096, NVME_CQ_SIZE(depth));
+	if (!nvmeq->cqes)
+		goto free_nvmeq;
+	memset((void *)nvmeq->cqes, 0, NVME_CQ_SIZE(depth));
+
+	nvmeq->sq_cmds = (void *)memalign(4096, NVME_SQ_SIZE(depth));
+	if (!nvmeq->sq_cmds)
+		goto free_queue;
+	memset((void *)nvmeq->sq_cmds, 0, NVME_SQ_SIZE(depth));
+
+	nvmeq->dev = dev;
+
+	nvmeq->cq_head = 0;
+	nvmeq->cq_phase = 1;
+	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
+	nvmeq->q_depth = depth;
+	nvmeq->qid = qid;
+	dev->queue_count++;
+	dev->queues[qid] = nvmeq;
+
+	return nvmeq;
+
+ free_queue:
+	free((void *)nvmeq->cqes);
+ free_nvmeq:
+	free(nvmeq);
+
+	return NULL;
+}
+
+static int nvme_delete_queue(struct nvme_dev *dev, u8 opcode, u16 id)
+{
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+	c.delete_queue.opcode = opcode;
+	c.delete_queue.qid = cpu_to_le16(id);
+
+	return nvme_submit_admin_cmd(dev, &c, NULL);
+}
+
+static int nvme_delete_sq(struct nvme_dev *dev, u16 sqid)
+{
+	return nvme_delete_queue(dev, nvme_admin_delete_sq, sqid);
+}
+
+static int nvme_delete_cq(struct nvme_dev *dev, u16 cqid)
+{
+	return nvme_delete_queue(dev, nvme_admin_delete_cq, cqid);
+}
+
+static int nvme_enable_ctrl(struct nvme_dev *dev)
+{
+	dev->ctrl_config &= ~NVME_CC_SHN_MASK;
+	dev->ctrl_config |= NVME_CC_ENABLE;
+	writel(cpu_to_le32(dev->ctrl_config), &dev->bar->cc);
+
+	return nvme_wait_ready(dev, true);
+}
+
+static int nvme_disable_ctrl(struct nvme_dev *dev)
+{
+	dev->ctrl_config &= ~NVME_CC_SHN_MASK;
+	dev->ctrl_config &= ~NVME_CC_ENABLE;
+	writel(cpu_to_le32(dev->ctrl_config), &dev->bar->cc);
+
+	return nvme_wait_ready(dev, false);
+}
+
+static void nvme_free_queue(struct nvme_queue *nvmeq)
+{
+	free((void *)nvmeq->cqes);
+	free(nvmeq->sq_cmds);
+	free(nvmeq);
+}
+
+static void nvme_free_queues(struct nvme_dev *dev, int lowest)
+{
+	int i;
+
+	for (i = dev->queue_count - 1; i >= lowest; i--) {
+		struct nvme_queue *nvmeq = dev->queues[i];
+		dev->queue_count--;
+		dev->queues[i] = NULL;
+		nvme_free_queue(nvmeq);
+	}
+}
+
+static void nvme_init_queue(struct nvme_queue *nvmeq, u16 qid)
+{
+	struct nvme_dev *dev = nvmeq->dev;
+
+	nvmeq->sq_tail = 0;
+	nvmeq->cq_head = 0;
+	nvmeq->cq_phase = 1;
+	nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];
+	memset((void *)nvmeq->cqes, 0, NVME_CQ_SIZE(nvmeq->q_depth));
+	flush_dcache_range((ulong)nvmeq->cqes,
+			   (ulong)nvmeq->cqes + NVME_CQ_SIZE(nvmeq->q_depth));
+	dev->online_queues++;
+}
+
+static int nvme_configure_admin_queue(struct nvme_dev *dev)
+{
+	int result;
+	u32 aqa;
+	u64 cap = nvme_readq(&dev->bar->cap);
+	struct nvme_queue *nvmeq;
+	/* most architectures use 4KB as the page size */
+	unsigned page_shift = 12;
+	unsigned dev_page_min = NVME_CAP_MPSMIN(cap) + 12;
+	unsigned dev_page_max = NVME_CAP_MPSMAX(cap) + 12;
+
+	if (page_shift < dev_page_min) {
+		debug("Device minimum page size (%u) too large for host (%u)\n",
+		      1 << dev_page_min, 1 << page_shift);
+		return -ENODEV;
+	}
+
+	if (page_shift > dev_page_max) {
+		debug("Device maximum page size (%u) smaller than host (%u)\n",
+		      1 << dev_page_max, 1 << page_shift);
+		page_shift = dev_page_max;
+	}
+
+	result = nvme_disable_ctrl(dev);
+	if (result < 0)
+		return result;
+
+	nvmeq = dev->queues[0];
+	if (!nvmeq) {
+		nvmeq = nvme_alloc_queue(dev, 0, NVME_AQ_DEPTH);
+		if (!nvmeq)
+			return -ENOMEM;
+	}
+
+	aqa = nvmeq->q_depth - 1;
+	aqa |= aqa << 16;
+	aqa |= aqa << 16;
+
+	dev->page_size = 1 << page_shift;
+
+	dev->ctrl_config = NVME_CC_CSS_NVM;
+	dev->ctrl_config |= (page_shift - 12) << NVME_CC_MPS_SHIFT;
+	dev->ctrl_config |= NVME_CC_ARB_RR | NVME_CC_SHN_NONE;
+	dev->ctrl_config |= NVME_CC_IOSQES | NVME_CC_IOCQES;
+
+	writel(aqa, &dev->bar->aqa);
+	nvme_writeq((ulong)nvmeq->sq_cmds, &dev->bar->asq);
+	nvme_writeq((ulong)nvmeq->cqes, &dev->bar->acq);
+
+	result = nvme_enable_ctrl(dev);
+	if (result)
+		goto free_nvmeq;
+
+	nvmeq->cq_vector = 0;
+
+	nvme_init_queue(dev->queues[0], 0);
+
+	return result;
+
+ free_nvmeq:
+	nvme_free_queues(dev, 0);
+
+	return result;
+}
+
+static int nvme_alloc_cq(struct nvme_dev *dev, u16 qid,
+			    struct nvme_queue *nvmeq)
+{
+	struct nvme_command c;
+	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_CQ_IRQ_ENABLED;
+
+	memset(&c, 0, sizeof(c));
+	c.create_cq.opcode = nvme_admin_create_cq;
+	c.create_cq.prp1 = cpu_to_le64((ulong)nvmeq->cqes);
+	c.create_cq.cqid = cpu_to_le16(qid);
+	c.create_cq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
+	c.create_cq.cq_flags = cpu_to_le16(flags);
+	c.create_cq.irq_vector = cpu_to_le16(nvmeq->cq_vector);
+
+	return nvme_submit_admin_cmd(dev, &c, NULL);
+}
+
+static int nvme_alloc_sq(struct nvme_dev *dev, u16 qid,
+			    struct nvme_queue *nvmeq)
+{
+	struct nvme_command c;
+	int flags = NVME_QUEUE_PHYS_CONTIG | NVME_SQ_PRIO_MEDIUM;
+
+	memset(&c, 0, sizeof(c));
+	c.create_sq.opcode = nvme_admin_create_sq;
+	c.create_sq.prp1 = cpu_to_le64((ulong)nvmeq->sq_cmds);
+	c.create_sq.sqid = cpu_to_le16(qid);
+	c.create_sq.qsize = cpu_to_le16(nvmeq->q_depth - 1);
+	c.create_sq.sq_flags = cpu_to_le16(flags);
+	c.create_sq.cqid = cpu_to_le16(qid);
+
+	return nvme_submit_admin_cmd(dev, &c, NULL);
+}
+
+int nvme_identify(struct nvme_dev *dev, unsigned nsid,
+		  unsigned cns, dma_addr_t dma_addr)
+{
+	struct nvme_command c;
+	u32 page_size = dev->page_size;
+	int offset = dma_addr & (page_size - 1);
+	int length = sizeof(struct nvme_id_ctrl);
+
+	memset(&c, 0, sizeof(c));
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.nsid = cpu_to_le32(nsid);
+	c.identify.prp1 = cpu_to_le64(dma_addr);
+
+	length -= (page_size - offset);
+	if (length <= 0) {
+		c.identify.prp2 = 0;
+	} else {
+		dma_addr += (page_size - offset);
+		c.identify.prp2 = dma_addr;
+	}
+
+	c.identify.cns = cpu_to_le32(cns);
+
+	return nvme_submit_admin_cmd(dev, &c, NULL);
+}
+
+int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid,
+		      dma_addr_t dma_addr, u32 *result)
+{
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+	c.features.opcode = nvme_admin_get_features;
+	c.features.nsid = cpu_to_le32(nsid);
+	c.features.prp1 = cpu_to_le64(dma_addr);
+	c.features.fid = cpu_to_le32(fid);
+
+	return nvme_submit_admin_cmd(dev, &c, result);
+}
+
+int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11,
+		      dma_addr_t dma_addr, u32 *result)
+{
+	struct nvme_command c;
+
+	memset(&c, 0, sizeof(c));
+	c.features.opcode = nvme_admin_set_features;
+	c.features.prp1 = cpu_to_le64(dma_addr);
+	c.features.fid = cpu_to_le32(fid);
+	c.features.dword11 = cpu_to_le32(dword11);
+
+	return nvme_submit_admin_cmd(dev, &c, result);
+}
+
+static int nvme_create_queue(struct nvme_queue *nvmeq, int qid)
+{
+	struct nvme_dev *dev = nvmeq->dev;
+	int result;
+
+	nvmeq->cq_vector = qid - 1;
+	result = nvme_alloc_cq(dev, qid, nvmeq);
+	if (result < 0)
+		goto release_cq;
+
+	result = nvme_alloc_sq(dev, qid, nvmeq);
+	if (result < 0)
+		goto release_sq;
+
+	nvme_init_queue(nvmeq, qid);
+
+	return result;
+
+ release_sq:
+	nvme_delete_sq(dev, qid);
+ release_cq:
+	nvme_delete_cq(dev, qid);
+
+	return result;
+}
+
+static int nvme_set_queue_count(struct nvme_dev *dev, int count)
+{
+	int status;
+	u32 result;
+	u32 q_count = (count - 1) | ((count - 1) << 16);
+
+	status = nvme_set_features(dev, NVME_FEAT_NUM_QUEUES,
+			q_count, 0, &result);
+
+	if (status < 0)
+		return status;
+	if (status > 1)
+		return 0;
+
+	return min(result & 0xffff, result >> 16) + 1;
+}
+
+static void nvme_create_io_queues(struct nvme_dev *dev)
+{
+	unsigned int i;
+
+	for (i = dev->queue_count; i <= dev->max_qid; i++)
+		if (!nvme_alloc_queue(dev, i, dev->q_depth))
+			break;
+
+	for (i = dev->online_queues; i <= dev->queue_count - 1; i++)
+		if (nvme_create_queue(dev->queues[i], i))
+			break;
+}
+
+static int nvme_setup_io_queues(struct nvme_dev *dev)
+{
+	int nr_io_queues;
+	int result;
+
+	nr_io_queues = 1;
+	result = nvme_set_queue_count(dev, nr_io_queues);
+	if (result <= 0)
+		return result;
+
+	if (result < nr_io_queues)
+		nr_io_queues = result;
+
+	dev->max_qid = nr_io_queues;
+
+	/* Free previously allocated queues */
+	nvme_free_queues(dev, nr_io_queues + 1);
+	nvme_create_io_queues(dev);
+
+	return 0;
+}
+
+static int nvme_get_info_from_identify(struct nvme_dev *dev)
+{
+	u16 vendor, device;
+	struct nvme_id_ctrl buf, *ctrl = &buf;
+	int ret;
+	int shift = NVME_CAP_MPSMIN(nvme_readq(&dev->bar->cap)) + 12;
+
+	ret = nvme_identify(dev, 0, 1, (dma_addr_t)ctrl);
+	if (ret)
+		return -EIO;
+
+	dev->nn = le32_to_cpu(ctrl->nn);
+	dev->vwc = ctrl->vwc;
+	memcpy(dev->serial, ctrl->sn, sizeof(ctrl->sn));
+	memcpy(dev->model, ctrl->mn, sizeof(ctrl->mn));
+	memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr));
+	if (ctrl->mdts)
+		dev->max_transfer_shift = (ctrl->mdts + shift);
+
+	/* Apply quirk stuff */
+	dm_pci_read_config16(dev->pdev, PCI_VENDOR_ID, &vendor);
+	dm_pci_read_config16(dev->pdev, PCI_DEVICE_ID, &device);
+	if ((vendor == PCI_VENDOR_ID_INTEL) &&
+	    (device == 0x0953) && ctrl->vs[3]) {
+		unsigned int max_transfer_shift;
+		dev->stripe_size = (ctrl->vs[3] + shift);
+		max_transfer_shift = (ctrl->vs[3] + 18);
+		if (dev->max_transfer_shift) {
+			dev->max_transfer_shift = min(max_transfer_shift,
+						      dev->max_transfer_shift);
+		} else {
+			dev->max_transfer_shift = max_transfer_shift;
+		}
+	}
+
+	return 0;
+}
+
+int nvme_scan_namespace(void)
+{
+	struct uclass *uc;
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_get(UCLASS_NVME, &uc);
+	if (ret)
+		return ret;
+
+	uclass_foreach_dev(dev, uc) {
+		ret = device_probe(dev);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int nvme_blk_probe(struct udevice *udev)
+{
+	struct nvme_dev *ndev = dev_get_priv(udev->parent);
+	struct blk_desc *desc = dev_get_uclass_platdata(udev);
+	struct nvme_ns *ns = dev_get_priv(udev);
+	u8 flbas;
+	u16 vendor;
+	struct nvme_id_ns buf, *id = &buf;
+
+	memset(ns, 0, sizeof(*ns));
+	ns->dev = ndev;
+	ns->ns_id = desc->devnum - ndev->blk_dev_start + 1;
+	if (nvme_identify(ndev, ns->ns_id, 0, (dma_addr_t)id))
+		return -EIO;
+
+	flbas = id->flbas & NVME_NS_FLBAS_LBA_MASK;
+	ns->flbas = flbas;
+	ns->lba_shift = id->lbaf[flbas].ds;
+	ns->mode_select_num_blocks = le64_to_cpu(id->nuse);
+	ns->mode_select_block_len = 1 << ns->lba_shift;
+	list_add(&ns->list, &ndev->namespaces);
+
+	desc->lba = ns->mode_select_num_blocks;
+	desc->log2blksz = ns->lba_shift;
+	desc->blksz = 1 << ns->lba_shift;
+	desc->bdev = udev;
+	dm_pci_read_config16(ndev->pdev, PCI_VENDOR_ID, &vendor);
+	sprintf(desc->vendor, "0x%.4x", vendor);
+	memcpy(desc->product, ndev->serial, sizeof(ndev->serial));
+	memcpy(desc->revision, ndev->firmware_rev, sizeof(ndev->firmware_rev));
+	part_init(desc);
+
+	return 0;
+}
+
+static ulong nvme_blk_read(struct udevice *udev, lbaint_t blknr,
+			   lbaint_t blkcnt, void *buffer)
+{
+	struct nvme_ns *ns = dev_get_priv(udev);
+	struct nvme_dev *dev = ns->dev;
+	struct nvme_command c;
+	struct blk_desc *desc = dev_get_uclass_platdata(udev);
+	int status;
+	u64 prp2;
+	u64 total_len = blkcnt << desc->log2blksz;
+	u64 temp_len = total_len;
+
+	u64 slba = blknr;
+	u16 lbas = 1 << (dev->max_transfer_shift - ns->lba_shift);
+	u64 total_lbas = blkcnt;
+
+	c.rw.opcode = nvme_cmd_read;
+	c.rw.flags = 0;
+	c.rw.nsid = cpu_to_le32(ns->ns_id);
+	c.rw.control = 0;
+	c.rw.dsmgmt = 0;
+	c.rw.reftag = 0;
+	c.rw.apptag = 0;
+	c.rw.appmask = 0;
+	c.rw.metadata = 0;
+
+	while (total_lbas) {
+		if (total_lbas < lbas) {
+			lbas = (u16)total_lbas;
+			total_lbas = 0;
+		} else {
+			total_lbas -= lbas;
+		}
+
+		if (nvme_setup_prps
+		   (dev, &prp2, lbas << ns->lba_shift, (ulong)buffer))
+			return -EIO;
+		c.rw.slba = cpu_to_le64(slba);
+		slba += lbas;
+		c.rw.length = cpu_to_le16(lbas - 1);
+		c.rw.prp1 = cpu_to_le64((ulong)buffer);
+		c.rw.prp2 = cpu_to_le64(prp2);
+		status = nvme_submit_sync_cmd(dev->queues[1],
+				&c, NULL, IO_TIMEOUT);
+		if (status)
+			break;
+		temp_len -= lbas << ns->lba_shift;
+		buffer += lbas << ns->lba_shift;
+	}
+
+	return (total_len - temp_len) >> desc->log2blksz;
+}
+
+static ulong nvme_blk_write(struct udevice *udev, lbaint_t blknr,
+			    lbaint_t blkcnt, const void *buffer)
+{
+	struct nvme_ns *ns = dev_get_priv(udev);
+	struct nvme_dev *dev = ns->dev;
+	struct nvme_command c;
+	struct blk_desc *desc = dev_get_uclass_platdata(udev);
+	int status;
+	u64 prp2;
+	u64 total_len = blkcnt << desc->log2blksz;
+	u64 temp_len = total_len;
+
+	u64 slba = blknr;
+	u16 lbas = 1 << (dev->max_transfer_shift - ns->lba_shift);
+	u64 total_lbas = blkcnt;
+
+	c.rw.opcode = nvme_cmd_write;
+	c.rw.flags = 0;
+	c.rw.nsid = cpu_to_le32(ns->ns_id);
+	c.rw.control = 0;
+	c.rw.dsmgmt = 0;
+	c.rw.reftag = 0;
+	c.rw.apptag = 0;
+	c.rw.appmask = 0;
+	c.rw.metadata = 0;
+
+	while (total_lbas) {
+		if (total_lbas < lbas) {
+			lbas = (u16)total_lbas;
+			total_lbas = 0;
+		} else {
+			total_lbas -= lbas;
+		}
+
+		if (nvme_setup_prps
+		   (dev, &prp2, lbas << ns->lba_shift, (ulong)buffer))
+			return -EIO;
+		c.rw.slba = cpu_to_le64(slba);
+		slba += lbas;
+		c.rw.length = cpu_to_le16(lbas - 1);
+		c.rw.prp1 = cpu_to_le64((ulong)buffer);
+		c.rw.prp2 = cpu_to_le64(prp2);
+		status = nvme_submit_sync_cmd(dev->queues[1],
+				&c, NULL, IO_TIMEOUT);
+		if (status)
+			break;
+		temp_len -= lbas << ns->lba_shift;
+		buffer += lbas << ns->lba_shift;
+	}
+
+	return (total_len - temp_len) >> desc->log2blksz;
+}
+
+static const struct blk_ops nvme_blk_ops = {
+	.read	= nvme_blk_read,
+	.write	= nvme_blk_write,
+};
+
+U_BOOT_DRIVER(nvme_blk) = {
+	.name	= "nvme-blk",
+	.id	= UCLASS_BLK,
+	.probe	= nvme_blk_probe,
+	.ops	= &nvme_blk_ops,
+	.priv_auto_alloc_size = sizeof(struct nvme_ns),
+};
+
+static int nvme_bind(struct udevice *udev)
+{
+	char name[20];
+	sprintf(name, "nvme#%d", nvme_info->ndev_num++);
+
+	return device_set_name(udev, name);
+}
+
+static int nvme_probe(struct udevice *udev)
+{
+	int ret;
+	struct nvme_dev *ndev = dev_get_priv(udev);
+	u64 cap;
+
+	ndev->pdev = pci_get_controller(udev);
+	ndev->instance = trailing_strtol(udev->name);
+
+	INIT_LIST_HEAD(&ndev->namespaces);
+	ndev->bar = dm_pci_map_bar(udev, PCI_BASE_ADDRESS_0,
+			PCI_REGION_MEM);
+	if (readl(&ndev->bar->csts) == -1) {
+		ret = -ENODEV;
+		printf("Error: %s: Out of memory!\n", udev->name);
+		goto free_nvme;
+	}
+
+	ndev->queues = malloc(2 * sizeof(struct nvme_queue));
+	if (!ndev->queues) {
+		ret = -ENOMEM;
+		printf("Error: %s: Out of memory!\n", udev->name);
+		goto free_nvme;
+	}
+	memset(ndev->queues, 0, sizeof(2 * sizeof(struct nvme_queue)));
+
+	ndev->prp_pool = malloc(MAX_PRP_POOL);
+	if (!ndev->prp_pool) {
+		ret = -ENOMEM;
+		printf("Error: %s: Out of memory!\n", udev->name);
+		goto free_nvme;
+	}
+	ndev->prp_entry_num = MAX_PRP_POOL >> 3;
+
+	cap = nvme_readq(&ndev->bar->cap);
+	ndev->q_depth = min_t(int, NVME_CAP_MQES(cap) + 1, NVME_Q_DEPTH);
+	ndev->db_stride = 1 << NVME_CAP_STRIDE(cap);
+	ndev->dbs = ((void __iomem *)ndev->bar) + 4096;
+
+	ret = nvme_configure_admin_queue(ndev);
+	if (ret)
+		goto free_queue;
+
+	ret = nvme_setup_io_queues(ndev);
+	if (ret)
+		goto free_queue;
+
+	nvme_get_info_from_identify(ndev);
+	ndev->blk_dev_start = nvme_info->ns_num;
+	list_add(&ndev->node, &nvme_info->dev_list);
+
+	return 0;
+
+free_queue:
+	free((void *)ndev->queues);
+free_nvme:
+	return ret;
+}
+
+U_BOOT_DRIVER(nvme) = {
+	.name	= "nvme",
+	.id	= UCLASS_NVME,
+	.bind	= nvme_bind,
+	.probe	= nvme_probe,
+	.priv_auto_alloc_size = sizeof(struct nvme_dev),
+};
+
+struct pci_device_id nvme_supported[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0953) },
+	{}
+};
+
+U_BOOT_PCI_DEVICE(nvme, nvme_supported);
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__ */
diff --git a/include/nvme.h b/include/nvme.h
new file mode 100644
index 0000000..3624408
--- /dev/null
+++ b/include/nvme.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2017 NXP Semiconductors
+ * Copyright (C) 2017 Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __NVME_H__
+#define __NVME_H__
+
+struct nvme_dev;
+
+/**
+ * nvme_identify - identify controller or namespace capabilities and status
+ *
+ * This issues an identify command to the NVMe controller to return a data
+ * buffer that describes the controller or namespace capabilities and status.
+ *
+ * @dev:	NVMe controller device
+ * @nsid:	0 for controller, namespace id for namespace to identify
+ * @cns:	1 for controller, 0 for namespace
+ * @dma_addr:	dma buffer address to store the identify result
+ * @return:	0 on success, -ETIMEDOUT on command execution timeout,
+ *		-EIO on command execution fails
+ */
+int nvme_identify(struct nvme_dev *dev, unsigned nsid,
+		  unsigned cns, dma_addr_t dma_addr);
+
+/**
+ * nvme_get_features - retrieve the attributes of the feature specified
+ *
+ * This retrieves the attributes of the feature specified.
+ *
+ * @dev:	NVMe controller device
+ * @fid:	feature id to provide data
+ * @nsid:	namespace id the command applies to
+ * @dma_addr:	data structure used as part of the specified feature
+ * @result:	command-specific result in the completion queue entry
+ * @return:	0 on success, -ETIMEDOUT on command execution timeout,
+ *		-EIO on command execution fails
+ */
+int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid,
+		      dma_addr_t dma_addr, u32 *result);
+
+/**
+ * nvme_set_features - specify the attributes of the feature indicated
+ *
+ * This specifies the attributes of the feature indicated.
+ *
+ * @dev:	NVMe controller device
+ * @fid:	feature id to provide data
+ * @dword11:	command-specific input parameter
+ * @dma_addr:	data structure used as part of the specified feature
+ * @result:	command-specific result in the completion queue entry
+ * @return:	0 on success, -ETIMEDOUT on command execution timeout,
+ *		-EIO on command execution fails
+ */
+int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11,
+		      dma_addr_t dma_addr, u32 *result);
+
+/**
+ * nvme_scan_namespace - scan all namespaces attached to NVMe controllers
+ *
+ * This probes all registered NVMe uclass device drivers in the system,
+ * and tries to find all namespaces attached to the NVMe controllers.
+ *
+ * @return:	0 on success, -ve on error
+ */
+int nvme_scan_namespace(void);
+
+#endif /* __NVME_H__ */