From: Keith Busch <keith.busch@intel.com>
Date: Mon, 2 Feb 2015 16:57:49 +0000 (-0700)
Subject: NVMe: Add show registers command
X-Git-Tag: v0.1~82
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=08290ca94abc89faa3b5aebf368370d04b25958a;p=users%2Fsagi%2Fnvme-cli.git

NVMe: Add show registers command

This prints out the controller registers in human readable format. It uses
knowledge of the sysfs layout to map a character device to a pci resource.

Signed-off-by: Keith Busch <keith.busch@intel.com>
---

diff --git a/Documentation/nvme-show-regs.txt b/Documentation/nvme-show-regs.txt
new file mode 100644
index 00000000..fff4460d
--- /dev/null
+++ b/Documentation/nvme-show-regs.txt
@@ -0,0 +1,34 @@
+nvme-id-ns(1)
+=============
+
+NAME
+----
+nvme-show-regs - Reads and shows the defined NVMe controller registers.
+
+SYNOPSIS
+--------
+[verse]
+'nvme show-regs' <device>
+
+DESCRIPTION
+-----------
+For the NVMe device given, sends an identify namespace command and
+provides the result and returned structure.
+
+The <device> parameter is mandatory and must be the nvme admin character
+device (ex: /dev/nvme0). The program uses knowledge of the sysfs layout
+to map the device to the pci resource stored there and mmaps the memory
+to get access to the registers.
+
+EXAMPLES
+--------
+* Has the program map the nvme pci controller registers and prints them
+in a human readable format:
++
+------------
+# nvme show-regs /dev/nvme0
+------------
+
+NVME
+----
+Part of the nvme-user suite
diff --git a/linux/nvme.h b/linux/nvme.h
index b2130dcb..97364836 100644
--- a/linux/nvme.h
+++ b/linux/nvme.h
@@ -568,6 +568,22 @@ struct nvme_passthru_cmd {
 	__u32	result;
 };
 
+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			nssr;	/* NVM Subsystem Reset */
+	__u32			aqa;	/* Admin Queue Attributes */
+	__u64			asq;	/* Admin SQ Base Address */
+	__u64			acq;	/* Admin CQ Base Address */
+	__u32			cmbloc;	/* Controller Memory Buffer Location */
+	__u32			cmbsz;	/* Controller Memory Buffer Size */
+};
+
 #define nvme_admin_cmd nvme_passthru_cmd
 
 #define NVME_IOCTL_ID		_IO('N', 0x40)
diff --git a/nvme.c b/nvme.c
index 38351007..bdcb2312 100644
--- a/nvme.c
+++ b/nvme.c
@@ -34,6 +34,7 @@
 #include <linux/fs.h>
 
 #include <sys/ioctl.h>
+#include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 
@@ -67,6 +68,7 @@ static const char *devicename;
 	ENTRY(RESV_REPORT, "resv-report", "Submit a Reservation Report, return results", resv_report) \
 	ENTRY(FLUSH, "flush", "Submit a Flush command, return results", flush) \
 	ENTRY(COMPARE, "compare", "Submit a Comapre command, return results", compare) \
+	ENTRY(REGISTERS, "show-regs", "Shows the controller registers. Requires admin character device", show_registers) \
 	ENTRY(HELP, "help", "Display this help", help)
 
 #define ENTRY(i, n, h, f) \
@@ -1073,6 +1075,54 @@ static int fw_activate(int argc, char **argv)
 	return err;
 }
 
+static int show_registers(int argc, char **argv)
+{
+	int opt, long_index, pci_fd;
+	char *base, path[512];
+	void *membase;
+	struct nvme_bar *bar;
+	static struct option opts[] = {};
+
+	while ((opt = getopt_long(argc, (char **)argv, "", opts,
+					&long_index)) != -1);
+	get_dev(optind, argc, argv);
+
+	if (!S_ISCHR(nvme_stat.st_mode)) {
+		fprintf(stderr, "%s is not character device\n", devicename);
+		exit(ENODEV);
+	}
+
+	base = basename(devicename);
+	sprintf(path, "/sys/class/misc/%s/device/resource0", base);
+	pci_fd = open(path, O_RDONLY);
+	if (pci_fd < 0) {
+		fprintf(stderr, "%s did not find a pci resource\n", devicename);
+		exit(ENODEV);
+	}
+
+	membase = mmap(0, getpagesize(), PROT_READ, MAP_SHARED, pci_fd, 0);
+	if (!membase) {
+		fprintf(stderr, "%s failed to map\n", devicename);
+		exit(ENODEV);
+	}
+
+	bar = membase;
+	printf("cap     : %"PRIx64"\n", (uint64_t)bar->cap);
+	printf("version : %x\n", bar->vs);
+	printf("intms   : %x\n", bar->intms);
+	printf("intmc   : %x\n", bar->intmc);
+	printf("cc      : %x\n", bar->cc);
+	printf("csts    : %x\n", bar->csts);
+	printf("nssr    : %x\n", bar->nssr);
+	printf("aqa     : %x\n", bar->aqa);
+	printf("asq     : %"PRIx64"\n", (uint64_t)bar->asq);
+	printf("acq     : %"PRIx64"\n", (uint64_t)bar->acq);
+	printf("cmbloc  : %x\n", bar->cmbloc);
+	printf("cmbsz   : %x\n", bar->cmbsz);
+
+	return 0;
+}
+
 static int format(int argc, char **argv)
 {
 	int opt, err, long_index;
@@ -1091,7 +1141,6 @@ static int format(int argc, char **argv)
 
 	while ((opt = getopt_long(argc, (char **)argv, "n:l:s:p:i:m:", opts,
 							&long_index)) != -1) {
-		
 		switch (opt) {
 		case 'n': get_int(optarg, &nsid); break;
 		case 'l': get_byte(optarg, &lbaf); break;