Hi Grygorii,

Thanks for reviewing this!

On 03/28/2018 03:01 PM, Grygorii Strashko wrote:

Hi Murali,

On 03/27/2018 11:31 AM, Murali Karicheri wrote:

quoted

Navigator Subsystem (NSS) available on K2G SoC has a cut down
version of QMSS with less number of queues, internal linking ram
with lesser number of buffers etc.  It doesn't have status and
explicit push register space as in QMSS available on other K2 SoCs.
So define reg indices specific to QMSS on K2G. This patch introduces
"keystone-navigator-qmss-l" compatibility to identify QMSS on
K2G NSS (QMSS Lite) and to customize the dts handling code. Per
Device manual, descriptors with index less than or equal to
regions0_size is in region 0 in the case of QMSS where as for
QMSS Lite, descriptors with index less than regions0_size is in
region 0. So update the size accordingly in the regions0_size bits
of the linking ram size 0 register.

Signed-off-by: Murali Karicheri <redacted>
Signed-off-by: WingMan Kwok <redacted>
---
  .../bindings/soc/ti/keystone-navigator-qmss.txt    |  7 ++
  drivers/soc/ti/knav_qmss.h                         |  6 ++
  drivers/soc/ti/knav_qmss_queue.c                   | 90 ++++++++++++++++------
  3 files changed, 81 insertions(+), 22 deletions(-)

diff --git a/Documentation/devicetree/bindings/soc/ti/keystone-navigator-qmss.txt b/Documentation/devicetree/bindings/soc/ti/keystone-navigator-qmss.txt
index 77cd42c..1b0878a 100644
--- a/Documentation/devicetree/bindings/soc/ti/keystone-navigator-qmss.txt
+++ b/Documentation/devicetree/bindings/soc/ti/keystone-navigator-qmss.txt

@@ -18,6 +18,7 @@ pool management.
  
  Required properties:
  - compatible	: Must be "ti,keystone-navigator-qmss";
+		: Must be "ti,keystone-navigator-qmss-l" for NSS Lite

I think, It will be more accurate to add K2G specific compat string
like "ti,66ak2g-navss-qm":

compatible = "ti,66ak2g-navss-qm", "ti,keystone-navigator-qmss";

because 66ak2g TRM doesn't mention "Navss light" and this Navss version is used
only in 66ak2g Soc. As result, 66ak2g Navss QM is subset of of keystone 2 Navss QM 
which should be defined in DT by adding more specific compat string in addition
to generic one.  

As I have mentioned in the commit description, it is not a subset of the K2
registers. There are some differences that makes it not compatible with K2 QMSS.
See my description, 

quoted

It doesn't have status and explicit push register space as in QMSS available on
other K2 SoCs.

And also

quoted

Per Device manual, descriptors with index less than or equal to
regions0_size is in region 0 in the case of QMSS where as for
QMSS Lite, descriptors with index less than regions0_size is in
region 0. So update the size accordingly in the regions0_size bits
of the linking ram size 0 register

So will have to use a specific compatible = "ti,66ak2g-navss-qm" for this QM IMO.

Murali

quoted

  - clocks	: phandle to the reference clock for this device.
  - queue-range	: <start number> total range of queue numbers for the device.
  - linkram0	: <address size> for internal link ram, where size is the total

@@ -39,6 +40,12 @@ Required properties:
  			  - Descriptor memory setup region.
  			  - Queue Management/Queue Proxy region for queue Push.
  			  - Queue Management/Queue Proxy region for queue Pop.
+
+For NSS lite, following QMSS reg indexes are used in that order

For 66AK2G NAVSS QM..

quoted

+			  - Queue Peek region.
+			  - Queue configuration region.
+			  - Queue Management/Queue Proxy region for queue Push/Pop.
+
  - queue-pools	: child node classifying the queue ranges into pools.
  		  Queue ranges are grouped into 3 type of pools:
  		  - qpend	    : pool of qpend(interruptible) queues

diff --git a/drivers/soc/ti/knav_qmss.h b/drivers/soc/ti/knav_qmss.h
index 905b974..5fa1ce6 100644
--- a/drivers/soc/ti/knav_qmss.h
+++ b/drivers/soc/ti/knav_qmss.h

@@ -292,6 +292,11 @@ struct knav_queue {
  	struct list_head		list;
  };
  
+enum qmss_version {
+	QMSS,
+	QMSS_LITE,

QMSS_66AK2G

quoted

+};
+
  struct knav_device {
  	struct device				*dev;
  	unsigned				base_id;

@@ -305,6 +310,7 @@ struct knav_device {
  	struct list_head			pools;
  	struct list_head			pdsps;
  	struct list_head			qmgrs;
+	enum qmss_version			version;
  };
  

[...]

quoted

  }
  
+/* Match table for of_platform binding */
+static const struct of_device_id keystone_qmss_of_match[] = {
+	{
+		.compatible = "ti,keystone-navigator-qmss",

		.data	= (void *)QMSS,

quoted

+	},
+	{
+		.compatible = "ti,keystone-navigator-qmss-l",
+		.data	= (void *)QMSS_LITE,
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, keystone_qmss_of_match);
+
  static int knav_queue_probe(struct platform_device *pdev)
  {
  	struct device_node *node = pdev->dev.of_node;
  	struct device_node *qmgrs, *queue_pools, *regions, *pdsps;
+	const struct of_device_id *match;
  	struct device *dev = &pdev->dev;
  	u32 temp[2];
  	int ret;

@@ -1700,6 +1749,10 @@ static int knav_queue_probe(struct platform_device *pdev)
  		return -ENOMEM;
  	}
  
+	match = of_match_device(of_match_ptr(keystone_qmss_of_match), dev);
+	if (match && match->data)
+		kdev->version = QMSS_LITE;

	if (match)
		kdev->version = match->data;
	else
		error?
[...]

-- 
Murali Karicheri
Linux Kernel, Keystone