nvme: Get rid of the global variable nvme_info

At present the NVMe uclass driver uses a global variable nvme_info
to store global information like namespace id, and NVMe controller
driver's priv struct has a blk_dev_start that is used to calculate
the namespace id based on the global information from nvme_info.

This is not a good design in the DM world and can be replaced with
the following changes:

- Encode the namespace id in the NVMe block device name during
  the NVMe uclass post probe
- Extract the namespace id from the device name during the NVMe
  block device probe
- Let BLK uclass calculate the devnum for us by passing -1 to
  blk_create_devicef() as the devnum

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>

drivers/nvme/nvme-uclass.c

@@ -11,18 +11,6 @@
 #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];
@@ -32,16 +20,17 @@ static int nvme_uclass_post_probe(struct udevice *udev)
 
 	/* Create a blk device for each namespace */
 	for (i = 0; i < ndev->nn; i++) {
-		sprintf(name, "blk#%d", nvme_info->ns_num);
+		/*
+		 * Encode the namespace id to the device name so that
+		 * we can extract it when doing the probe.
+		 */
+		sprintf(name, "blk#%d", i);
 
 		/* The real blksz and size will be set by nvme_blk_probe() */
 		ret = blk_create_devicef(udev, "nvme-blk", name, IF_TYPE_NVME,
-					 nvme_info->ns_num++, 512, 0, &ns_udev);
-		if (ret) {
-			nvme_info->ns_num--;
-
+					 -1, 512, 0, &ns_udev);
+		if (ret)
 			return ret;
-		}
 	}
 
 	return 0;
@@ -50,7 +39,5 @@ static int nvme_uclass_post_probe(struct udevice *udev)
 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),
 };

drivers/nvme/nvme.c

@@ -13,8 +13,6 @@
 #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))
@@ -650,7 +648,8 @@ static int nvme_blk_probe(struct udevice *udev)
 
 	memset(ns, 0, sizeof(*ns));
 	ns->dev = ndev;
-	ns->ns_id = desc->devnum - ndev->blk_dev_start + 1;
+	/* extract the namespace id from the block device name */
+	ns->ns_id = trailing_strtol(udev->name) + 1;
 	if (nvme_identify(ndev, ns->ns_id, 0, (dma_addr_t)id))
 		return -EIO;
 
@@ -762,8 +761,10 @@ U_BOOT_DRIVER(nvme_blk) = {
 
 static int nvme_bind(struct udevice *udev)
 {
+	static int ndev_num;
 	char name[20];
-	sprintf(name, "nvme#%d", nvme_info->ndev_num++);
+
+	sprintf(name, "nvme#%d", ndev_num++);
 
 	return device_set_name(udev, name);
 }
@@ -815,8 +816,6 @@ static int nvme_probe(struct udevice *udev)
 		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;
 

drivers/nvme/nvme.h

@@ -628,13 +628,6 @@ struct nvme_dev {
 	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;
 };
 
 /*
@@ -652,6 +645,4 @@ struct nvme_ns {
 	u32 mode_select_block_len;
 };
 
-extern struct nvme_info *nvme_info;
-
 #endif /* __DRIVER_NVME_H__ */