[PATCH 2/2] nvme: improve cmb sysfs reporting

Stephen Bates
2016-12-16T19:19:52Z

Add more information to the NVMe CMB sysfs entry. This includes
information about the CMB size, location and capabilities.

Signed-off-by: Stephen Bates <sbates@raithlin.com>
---
drivers/nvme/host/pci.c | 31 +++++++++++++++++++++++++++++--
include/linux/nvme.h | 8 ++++++++
2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index be10860..1f70630 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -98,6 +98,7 @@ struct nvme_dev {
void __iomem *cmb;
dma_addr_t cmb_dma_addr;
u64 cmb_size;
+ u64 cmb_offset;
u32 cmbsz;
u32 cmbloc;
struct nvme_ctrl ctrl;
@@ -1326,14 +1327,39 @@ static int nvme_create_io_queues(struct nvme_dev *dev)
return ret >= 0 ? 0 : ret;
}

+static const char * const cmb_caps[] = {
+ [NVME_CMB_CAP_SQS] = "SQS",
+ [NVME_CMB_CAP_CQS] = "CQS",
+ [NVME_CMB_CAP_LISTS] = "LISTS",
+ [NVME_CMB_CAP_RDS] = "RDS",
+ [NVME_CMB_CAP_WDS] = "WDS",
+};
+
static ssize_t nvme_cmb_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct nvme_dev *ndev = to_nvme_dev(dev_get_drvdata(dev));
+ unsigned int i, len = 0;
+
+ len += scnprintf(buf+len, PAGE_SIZE-len,
+ "cmbloc : 0x%08x\ncmbsz : 0x%08x\n\n",
+ ndev->cmbloc, ndev->cmbsz);
+
+ len += scnprintf(buf+len, PAGE_SIZE-len,
+ "OFFSET : 0x%016llx\nSIZE : %llu Bytes\n" \
+ "DMA ADDR : %pad\n\n",
+ ndev->cmb_offset, ndev->cmb_size,
+ &ndev->cmb_dma_addr);
+
+ for (i = NVME_CMB_CAP_SQS; i <= NVME_CMB_CAP_WDS; i++)
+ len += scnprintf(buf+len, PAGE_SIZE-len, "%-7s: %s\n",
+ cmb_caps[i],
+ ((ndev->cmbsz) & (1<<i)) ? "SUPPORTED" :
+ "NOT SUPPORTED");
+
+ return len;

- return scnprintf(buf, PAGE_SIZE, "cmbloc : x%08x\ncmbsz : x%08x\n",
- ndev->cmbloc, ndev->cmbsz);
}
static DEVICE_ATTR(cmb, S_IRUGO, nvme_cmb_show, NULL);

@@ -1376,6 +1402,7 @@ static void __iomem *nvme_map_cmb(struct nvme_dev *dev)

dev->cmb_dma_addr = dma_addr;
dev->cmb_size = size;
+ dev->cmb_offset = offset;
return cmb;
}

diff --git a/include/linux/nvme.h b/include/linux/nvme.h
index fc3c242..cd0d324 100644
--- a/include/linux/nvme.h
+++ b/include/linux/nvme.h
@@ -121,6 +121,14 @@ enum {
#define NVME_CMB_CQS(cmbsz) ((cmbsz) & 0x2)
#define NVME_CMB_SQS(cmbsz) ((cmbsz) & 0x1)

+enum {
+ NVME_CMB_CAP_SQS = 0,
+ NVME_CMB_CAP_CQS,
+ NVME_CMB_CAP_LISTS,
+ NVME_CMB_CAP_RDS,
+ NVME_CMB_CAP_WDS,
+};
+
/*
* Submission and Completion Queue Entry Sizes for the NVM command set.
* (In bytes and specified as a power of two (2^n)).
--
2.1.4