[PATCH] cxl: add option to enable -DDEBUG

[PATCH] cxl: add option to enable -DDEBUG

[Andrew Donnellan]

Developers working on AFUs and AFU drivers often find it useful to see the
pr_devel() and dev_dbg() messages from cxl. Give them an easy way to enable
-DDEBUG by adding a Kconfig option, CONFIG_CXL_DEBUG.

Inspired-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
---
 drivers/misc/cxl/Kconfig  | 12 ++++++++++++
 drivers/misc/cxl/Makefile |  1 +
 2 files changed, 13 insertions(+)

diff --git a/drivers/misc/cxl/Kconfig b/drivers/misc/cxl/Kconfig
index b75cf83..88ad9f1 100644
--- a/drivers/misc/cxl/Kconfig
+++ b/drivers/misc/cxl/Kconfig
@@ -36,3 +36,15 @@ config CXL_BIMODAL
 	help
 	  Select this option to enable support for bi-modal CAPI cards, such as
 	  the Mellanox CX-4.
+
+config CXL_DEBUG
+	bool "Enable additional CXL debug output"
+	depends on CXL
+	default n
+	help
+	  Select this option to enable additional debug output from the cxl
+	  driver. This may be useful if you're developing or debugging a CAPI
+	  Accelerator Function Unit or cxl-dependent device driver, but is
+	  generally not useful for end users.
+
+	  If unsure, say N.
diff --git a/drivers/misc/cxl/Makefile b/drivers/misc/cxl/Makefile
index 8a55c1a..620b132 100644
--- a/drivers/misc/cxl/Makefile
+++ b/drivers/misc/cxl/Makefile
@@ -1,5 +1,6 @@
 ccflags-y			:= $(call cc-disable-warning, unused-const-variable)
 ccflags-$(CONFIG_PPC_WERROR)	+= -Werror
+ccflags-$(CONFIG_CXL_DEBUG)	+= -DDEBUG
 
 cxl-y				+= main.o file.o irq.o fault.o native.o
 cxl-y				+= context.o sysfs.o debugfs.o pci.o trace.o
-- 
Andrew Donnellan              OzLabs, ADL Canberra
andrew.donnellan@au1.ibm.com  IBM Australia Limited

Re: [PATCH] cxl: add option to enable -DDEBUG

[Ian Munsie]

Acked-by: Ian Munsie <imunsie@au1.ibm.com>

Re: [PATCH] cxl: add option to enable -DDEBUG

[Michael Ellerman]

Andrew Donnellan <andrew.donnellan@au1.ibm.com> writes:

> Developers working on AFUs and AFU drivers often find it useful to see the
> pr_devel() and dev_dbg() messages from cxl. Give them an easy way to enable
> -DDEBUG by adding a Kconfig option, CONFIG_CXL_DEBUG.

Another option is to use DYNAMIC_DEBUG. If you turn that on the
dev_dbg()'s can be enabled at runtime, and you could en masse or
selectively convert the pr_devel()s to pr_debug() to get the same
result.

cheers

Re: [PATCH] cxl: add option to enable -DDEBUG

[Uma Krishnan]

On 7/18/2016 5:49 AM, Michael Ellerman wrote:
> Andrew Donnellan <andrew.donnellan@au1.ibm.com> writes:
>
>> Developers working on AFUs and AFU drivers often find it useful to see the
>> pr_devel() and dev_dbg() messages from cxl. Give them an easy way to enable
>> -DDEBUG by adding a Kconfig option, CONFIG_CXL_DEBUG.
>
> Another option is to use DYNAMIC_DEBUG. If you turn that on the
> dev_dbg()'s can be enabled at runtime, and you could en masse or
> selectively convert the pr_devel()s to pr_debug() to get the same
> result.
>
> cheers
>

Andrew, DYNAMIC_DEBUG would be more useful for us because it can be 
enabled at runtime just like we do for cxlflash.