[RFC PATCH 12/14] cxl: Add basic debugging
From: Ben Widawsky
Date: Tue Dec 08 2020 - 19:28:09 EST
Provide a standard debug function for use throughout the driver.
Signed-off-by: Ben Widawsky <ben.widawsky@xxxxxxxxx>
---
drivers/cxl/cxl.h | 3 +++
drivers/cxl/mem.c | 26 +++++++++++++++++++++++++-
2 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 77c2dee6843c..e5afb89dab0b 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -9,6 +9,9 @@
#include <linux/bitops.h>
#include <linux/io.h>
+#define cxl_debug(fmt, ...) \
+ pr_debug("CXL DEBUG: %s: " fmt, __func__, ##__VA_ARGS__)
+
#define CXL_SET_FIELD(value, field) \
({ \
WARN_ON(!FIELD_FIT(field##_MASK, value)); \
diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index a2cea7ac7cc6..6b2f8d3776b5 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -122,9 +122,12 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
{
const int timeout = msecs_to_jiffies(2000);
const unsigned long start = jiffies;
+ unsigned long end = start;
while (cxl_doorbell_busy(cxlm)) {
- if (time_after(jiffies, start + timeout)) {
+ end = jiffies;
+
+ if (time_after(end, start + timeout)) {
/* Check again in case preempted before timeout test */
if (!cxl_doorbell_busy(cxlm))
break;
@@ -133,6 +136,8 @@ static int cxl_mem_wait_for_doorbell(struct cxl_mem *cxlm)
cpu_relax();
}
+ cxl_debug("Doorbell wait took %dms",
+ jiffies_to_msecs(end) - jiffies_to_msecs(start));
return 0;
}
@@ -180,6 +185,8 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm,
}
/* #4 */
+ cxl_debug("Sending command to %s\n",
+ dev_driver_string(&cxlm->pdev->dev));
cxl_write_mbox_reg32(cxlm, CXLDEV_MB_CTRL_OFFSET,
CXLDEV_MB_CTRL_DOORBELL);
@@ -308,6 +315,8 @@ static int cxl_mem_open(struct inode *inode, struct file *file)
if (!cxlmd)
return -ENXIO;
+ cxl_debug("Opened %pD\n", file);
+
file->private_data = cxlmd;
return 0;
@@ -383,6 +392,10 @@ static int handle_mailbox_cmd_from_user(struct cxl_memdev *cxlmd,
.size_in = cmd->info.size_in,
.size_out = size_out,
};
+ cxl_debug("Submitting command for user\n"
+ "\topcode: %x\n"
+ "\tsize: %zub/%zub\n",
+ mbox_cmd.opcode, mbox_cmd.size_in, mbox_cmd.size_out);
rc = cxl_mem_mbox_send_cmd(cxlmd->cxlm, &mbox_cmd);
cxl_mem_mbox_put(cxlmd->cxlm);
if (rc)
@@ -479,6 +492,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
u32 n_commands;
int i, j;
+ cxl_debug("Query IOCTL\n");
+
if (get_user(n_commands, (u32 __user *)arg))
return -EFAULT;
@@ -511,6 +526,8 @@ static long cxl_mem_ioctl(struct file *file, unsigned int cmd, unsigned long arg
struct cxl_mem_command c;
int rc;
+ cxl_debug("Send IOCTL\n");
+
rc = cxl_validate_cmd_from_user(u, &c);
if (rc)
return rc;
@@ -843,6 +860,13 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
id = (struct cxl_mbox_identify *)mbox_cmd.payload;
+ cxl_debug("Driver identify command\n"
+ "\tFirmware Version: %s\n"
+ "\tTotal Capacity: %llu (%llu persistent)\n"
+ "\tLSA size: %u\n",
+ id->fw_revision, id->total_capacity, id->persistent_capacity,
+ id->lsa_size);
+
/*
* TODO: enumerate DPA map, as 'ram' and 'pmem' do not alias.
* For now, only the capacity is exported in sysfs
--
2.29.2