[PATCH V2 1/3] Documentation: DT: qcom_hidma: bump HW revision for the bugfixed HW

[PATCH V2 1/3] Documentation: DT: qcom_hidma: bump HW revision for the bugfixed HW

[Sinan Kaya]

A new version of the HIDMA IP has been released with bug fixes. Bumping the
hardware version to differentiate from others.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
 Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt b/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt
index 55492c2..5d93d6d 100644
--- a/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt
+++ b/Documentation/devicetree/bindings/dma/qcom_hidma_mgmt.txt
@@ -47,8 +47,8 @@ When the OS is not in control of the management interface (i.e. it's a guest),
 the channel nodes appear on their own, not under a management node.
 
 Required properties:
-- compatible: must contain "qcom,hidma-1.0" for initial HW or "qcom,hidma-1.1"
-for MSI capable HW.
+- compatible: must contain "qcom,hidma-1.0" for initial HW or
+  "qcom,hidma-1.1"/"qcom,hidma-1.2" for MSI capable HW.
 - reg: Addresses for the transfer and event channel
 - interrupts: Should contain the event interrupt
 - desc-count: Number of asynchronous requests this channel can handle
-- 
1.9.1

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Sinan Kaya]

Add support for probing the newer HW and also organize MSI capable hardware
into an array for maintenance reasons.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
 drivers/dma/qcom/hidma.c | 41 +++++++++++++++++++++++++++++------------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
index e366985..4ef7d6f 100644
--- a/drivers/dma/qcom/hidma.c
+++ b/drivers/dma/qcom/hidma.c
@@ -50,6 +50,7 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/of_dma.h>
+#include <linux/of_device.h>
 #include <linux/property.h>
 #include <linux/delay.h>
 #include <linux/acpi.h>
@@ -104,6 +105,26 @@ static void hidma_free(struct hidma_dev *dmadev)
 module_param(nr_desc_prm, uint, 0644);
 MODULE_PARM_DESC(nr_desc_prm, "number of descriptors (default: 0)");
 
+#define HIDMA_MAX_DEV_MATCH 10
+
+struct hidma_cap {
+	const struct of_device_id of[HIDMA_MAX_DEV_MATCH];
+	const struct acpi_device_id acpi[HIDMA_MAX_DEV_MATCH];
+};
+
+static struct hidma_cap hidma_msi_cap = {
+	.of = {
+		{.compatible = "qcom,hidma-1.1",},
+		{.compatible = "qcom,hidma-1.2",},
+		{},
+	},
+
+	.acpi = {
+		{"QCOM8062"},
+		{"QCOM8063"},
+		{},
+	}
+};
 
 /* process completed descriptors */
 static void hidma_process_completed(struct hidma_chan *mchan)
@@ -739,22 +760,16 @@ static int hidma_request_msi(struct hidma_dev *dmadev,
 static bool hidma_msi_capable(struct device *dev)
 {
 	struct acpi_device *adev = ACPI_COMPANION(dev);
-	const char *of_compat;
-	int ret = -EINVAL;
-
-	if (!adev || acpi_disabled) {
-		ret = device_property_read_string(dev, "compatible",
-						  &of_compat);
-		if (ret)
-			return false;
+	int ret;
 
-		ret = strcmp(of_compat, "qcom,hidma-1.1");
-	} else {
+	if (!adev || acpi_disabled)
+		ret = of_match_device(hidma_msi_cap.of, dev) != NULL;
+	else {
 #ifdef CONFIG_ACPI
-		ret = strcmp(acpi_device_hid(adev), "QCOM8062");
+		ret = acpi_match_device(hidma_msi_cap.acpi, dev) != NULL;
 #endif
 	}
-	return ret == 0;
+	return ret;
 }
 
 static int hidma_probe(struct platform_device *pdev)
@@ -954,6 +969,7 @@ static int hidma_remove(struct platform_device *pdev)
 static const struct acpi_device_id hidma_acpi_ids[] = {
 	{"QCOM8061"},
 	{"QCOM8062"},
+	{"QCOM8063"},
 	{},
 };
 MODULE_DEVICE_TABLE(acpi, hidma_acpi_ids);
@@ -962,6 +978,7 @@ static int hidma_remove(struct platform_device *pdev)
 static const struct of_device_id hidma_match[] = {
 	{.compatible = "qcom,hidma-1.0",},
 	{.compatible = "qcom,hidma-1.1",},
+	{.compatible = "qcom,hidma-1.2",},
 	{},
 };
 MODULE_DEVICE_TABLE(of, hidma_match);
-- 
1.9.1

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Timur Tabi]

On 11/08/2017 10:29 AM, Sinan Kaya wrote:
> +#define HIDMA_MAX_DEV_MATCH 10
> +
> +struct hidma_cap {
> +	const struct of_device_id of[HIDMA_MAX_DEV_MATCH];
> +	const struct acpi_device_id acpi[HIDMA_MAX_DEV_MATCH];
> +};

This seems wrong.  You're defining an array of size 10, but it only has 
three elements.  And the third element is a sentinel, which is typically 
used to avoid specifying the size of the array.

-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Sinan Kaya]

On 11/8/2017 11:49 AM, Timur Tabi wrote:
> On 11/08/2017 10:29 AM, Sinan Kaya wrote:
>> +#define HIDMA_MAX_DEV_MATCH 10
>> +
>> +struct hidma_cap {
>> +??? const struct of_device_id of[HIDMA_MAX_DEV_MATCH];
>> +??? const struct acpi_device_id acpi[HIDMA_MAX_DEV_MATCH];
>> +};
> 
> This seems wrong.? You're defining an array of size 10, but it only has three elements.? And the third element is a sentinel, which is typically used to avoid specifying the size of the array.
> 

It is true that I define an array of size 10. It is just some arbitrary number
with forward thinking. I don't really have to use it to the maximum today as long
as I satisfy the calling conventions.

What is important is that the of_device_match() and acpi_device_match() functions
will stop searching only if they find an empty element. The {} element.

That's the calling semantics of of_device_match() and acpi_device_match().

Besides, C compiler also won't let me put two arrays together like this.

struct my_struct {
	struct some_struct array1[]
	struct some_struct array2[]
}

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Timur Tabi]

On 11/08/2017 10:58 AM, Sinan Kaya wrote:
> Besides, C compiler also won't let me put two arrays together like this.
> 
> struct my_struct {
> 	struct some_struct array1[]
> 	struct some_struct array2[]
> }

Why not this:

const struct of_device_id hidma_msi_of_ids[] = {
	{.compatible = "qcom,hidma-1.1",},
	{.compatible = "qcom,hidma-1.2",},
	{},
},

static const struct acpi_device_id hidma_msi_acpi_ids[] = {
	{"QCOM8001", QDF2XXX_V1},
	{"QCOM8002", QDF2XXX_V2},
	{},
};

struct hidma_cap {
	const struct of_device_id *of;
	const struct acpi_device_id *acpi;
};

static struct hidma_cap hidma_msi_cap = {
	hidma_msi_of_ids,
	hidma_msi_acpi_ids
}

Keep in mind that you also need to add MODULE_DEVICE_TABLE entries, 
which you can't really do with your approach.

MODULE_DEVICE_TABLE(of, hidma_msi_of_ids);
MODULE_DEVICE_TABLE(acpi, hidma_msi_acpi_ids);

-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Sinan Kaya]

On 11/8/2017 12:12 PM, Timur Tabi wrote:
> On 11/08/2017 10:58 AM, Sinan Kaya wrote:
>> Besides, C compiler also won't let me put two arrays together like this.
>>
>> struct my_struct {
>> ????struct some_struct array1[]
>> ????struct some_struct array2[]
>> }
> 
> Why not this:
> 
> const struct of_device_id hidma_msi_of_ids[] = {
> ????{.compatible = "qcom,hidma-1.1",},
> ????{.compatible = "qcom,hidma-1.2",},
> ????{},
> },
> 
> static const struct acpi_device_id hidma_msi_acpi_ids[] = {
> ????{"QCOM8001", QDF2XXX_V1},
> ????{"QCOM8002", QDF2XXX_V2},
> ????{},
> };
> 
> struct hidma_cap {
> ????const struct of_device_id *of;
> ????const struct acpi_device_id *acpi;
> };
> 
> static struct hidma_cap hidma_msi_cap = {
> ????hidma_msi_of_ids,
> ????hidma_msi_acpi_ids
> }
> 

I think we are talking styles here. I started with your proposal and wanted to group
the settings together as much as I can for maintenance reasons only because 
I don't have to remember that there are two different arrays that I need to take care
of when I add a new HW in the future.

+static struct hidma_cap hidma_msi_cap = {
+	.of = {
+		{.compatible = "qcom,hidma-1.1",},
+		{.compatible = "qcom,hidma-1.2",},
+		{},
+	},
+
+	.acpi = {
+		{"QCOM8062"},
+		{"QCOM8063"},
+		{},
+	}
+};

I like this better than what you are proposing.

> Keep in mind that you also need to add MODULE_DEVICE_TABLE entries, which you can't really do with your approach.
> 
> MODULE_DEVICE_TABLE(of, hidma_msi_of_ids);
> MODULE_DEVICE_TABLE(acpi, hidma_msi_acpi_ids);
> 

HIDMA capable devices are a subset of the devices that need to be probed. That's also
why I don't touch the device_table.

In the end both approaches work. It is a choice between what is more manageable. That
was the initial objection. I tried to close on this request.

-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Timur Tabi]

On 11/08/2017 11:37 AM, Sinan Kaya wrote:
> I think we are talking styles here.

I don't think my suggestions are stylistic.  Your version wastes space.

However, if you really insist on your approach, that's fine with me. 
I'm not the maintainer.

-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Robin Murphy]

On 08/11/17 16:29, Sinan Kaya wrote:
> Add support for probing the newer HW and also organize MSI capable hardware
> into an array for maintenance reasons.
> 
> Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
> ---
>   drivers/dma/qcom/hidma.c | 41 +++++++++++++++++++++++++++++------------
>   1 file changed, 29 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
> index e366985..4ef7d6f 100644
> --- a/drivers/dma/qcom/hidma.c
> +++ b/drivers/dma/qcom/hidma.c
> @@ -50,6 +50,7 @@
>   #include <linux/slab.h>
>   #include <linux/spinlock.h>
>   #include <linux/of_dma.h>
> +#include <linux/of_device.h>
>   #include <linux/property.h>
>   #include <linux/delay.h>
>   #include <linux/acpi.h>
> @@ -104,6 +105,26 @@ static void hidma_free(struct hidma_dev *dmadev)
>   module_param(nr_desc_prm, uint, 0644);
>   MODULE_PARM_DESC(nr_desc_prm, "number of descriptors (default: 0)");
>   
> +#define HIDMA_MAX_DEV_MATCH 10
> +
> +struct hidma_cap {
> +	const struct of_device_id of[HIDMA_MAX_DEV_MATCH];
> +	const struct acpi_device_id acpi[HIDMA_MAX_DEV_MATCH];
> +};
> +
> +static struct hidma_cap hidma_msi_cap = {
> +	.of = {
> +		{.compatible = "qcom,hidma-1.1",},
> +		{.compatible = "qcom,hidma-1.2",},
> +		{},
> +	},
> +
> +	.acpi = {
> +		{"QCOM8062"},
> +		{"QCOM8063"},
> +		{},
> +	}
> +};

Yikes, I dread to imagine where this is going...

Apologies if I wasn't very clear, but what I meant to imply by dropping 
the of_device_get_match_data() hint was to follow one of the common 
patterns where you either just have some version token:

	enum foo_ver {
		FOO_V1,
		...
	}

	struct acpi_device_id foo_acpi_ids[] = {
		{ "_FOO0001", FOO_V1 },
		...
	}

	struct of_device_id foo_of_match[] = {
		{ .compatible = "foo,v1", .data = (void *)FOO_V1 },
		...
	}

	int foo_probe(struct device *dev) {
		...
		foodev->version = (enum foo_ver)
				of_device_get_match_data(&dev->of_node)
		...
	}

	int foo_reset(struct foodev *foodev) {
		if (foodev->version == FOO_V1)
			writel(0, foodev->base + 0x20);
		else
			writel(0, foodev->base + 0x30);
	}

or if it fits the code better, encapsulate the relevant details directly:

	struct foodata {
		.offset = 0x20,
	} foo_v1_data;

	struct acpi_device_id foo_acpi_ids[] = {
		{ "_FOO0001", (unsigned long)&foo_v1_data },
		...
	}

	struct of_device_id foo_of_match[] = {
		{ .compatible = "foo,v1", .data = &foo_v1_data },
		...
	}

	int foo_probe(struct device *dev) {
		...
		foodev->data = of_device_get_match_data(dev->of_node)
		...
	}

	int foo_reset(struct foodev *foodev) {
		writel(0, foodev->base + foodev->data->offset);
	}
			
Creating multiple sets of match tables seems completely backwards, and 
frankly looks worse than the open-coded strcmps IMO.

Robin.

>   
>   /* process completed descriptors */
>   static void hidma_process_completed(struct hidma_chan *mchan)
> @@ -739,22 +760,16 @@ static int hidma_request_msi(struct hidma_dev *dmadev,
>   static bool hidma_msi_capable(struct device *dev)
>   {
>   	struct acpi_device *adev = ACPI_COMPANION(dev);
> -	const char *of_compat;
> -	int ret = -EINVAL;
> -
> -	if (!adev || acpi_disabled) {
> -		ret = device_property_read_string(dev, "compatible",
> -						  &of_compat);
> -		if (ret)
> -			return false;
> +	int ret;
>   
> -		ret = strcmp(of_compat, "qcom,hidma-1.1");
> -	} else {
> +	if (!adev || acpi_disabled)
> +		ret = of_match_device(hidma_msi_cap.of, dev) != NULL;
> +	else {
>   #ifdef CONFIG_ACPI
> -		ret = strcmp(acpi_device_hid(adev), "QCOM8062");
> +		ret = acpi_match_device(hidma_msi_cap.acpi, dev) != NULL;
>   #endif
>   	}
> -	return ret == 0;
> +	return ret;
>   }
>   
>   static int hidma_probe(struct platform_device *pdev)
> @@ -954,6 +969,7 @@ static int hidma_remove(struct platform_device *pdev)
>   static const struct acpi_device_id hidma_acpi_ids[] = {
>   	{"QCOM8061"},
>   	{"QCOM8062"},
> +	{"QCOM8063"},
>   	{},
>   };
>   MODULE_DEVICE_TABLE(acpi, hidma_acpi_ids);
> @@ -962,6 +978,7 @@ static int hidma_remove(struct platform_device *pdev)
>   static const struct of_device_id hidma_match[] = {
>   	{.compatible = "qcom,hidma-1.0",},
>   	{.compatible = "qcom,hidma-1.1",},
> +	{.compatible = "qcom,hidma-1.2",},
>   	{},
>   };
>   MODULE_DEVICE_TABLE(of, hidma_match);
> 

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Sinan Kaya]

+linux-acpi, +Rafael for context

On 11/8/2017 12:51 PM, Robin Murphy wrote:
> Apologies if I wasn't very clear, but what I meant to imply by dropping the of_device_get_match_data() hint was to follow one of the common patterns where you either just have some version token:
> 
> ????enum foo_ver {
> ??????? FOO_V1,
> ??????? ...
> ????}
> 
> ????struct acpi_device_id foo_acpi_ids[] = {
> ??????? { "_FOO0001", FOO_V1 },
> ??????? ...
> ????}
> 
> ????struct of_device_id foo_of_match[] = {
> ??????? { .compatible = "foo,v1", .data = (void *)FOO_V1 },
> ??????? ...
> ????}
> 
> ????int foo_probe(struct device *dev) {
> ??????? ...
> ??????? foodev->version = (enum foo_ver)
> ??????????????? of_device_get_match_data(&dev->of_node)
> ??????? ...
> ????}
> 
> ????int foo_reset(struct foodev *foodev) {
> ??????? if (foodev->version == FOO_V1)
> ??????????? writel(0, foodev->base + 0x20);
> ??????? else
> ??????????? writel(0, foodev->base + 0x30);
> ????}

I did post v3 with this approach. However, I could not really find a ACPI function that
returns the driver data very similar to of_device_get_match_data(). The only thing
that is closer is acpi_match_device().

I introduced this new function as part of the v3 series. 

Let me know if I'm missing something.


-- 
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Timur Tabi]

On 11/10/2017 08:03 AM, Sinan Kaya wrote:
> I did post v3 with this approach. However, I could not really find a ACPI function that
> returns the driver data very similar to of_device_get_match_data(). The only thing
> that is closer is acpi_match_device().

This is what I do in the EMAC driver:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c#n245

-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.

[PATCH V2 2/3] dmaengine: qcom_hidma: add support for the new revision

[Robin Murphy]

On 10/11/17 14:03, Sinan Kaya wrote:
> +linux-acpi, +Rafael for context
> 
> On 11/8/2017 12:51 PM, Robin Murphy wrote:
>> Apologies if I wasn't very clear, but what I meant to imply by dropping the of_device_get_match_data() hint was to follow one of the common patterns where you either just have some version token:
>>
>>  ????enum foo_ver {
>>  ??????? FOO_V1,
>>  ??????? ...
>>  ????}
>>
>>  ????struct acpi_device_id foo_acpi_ids[] = {
>>  ??????? { "_FOO0001", FOO_V1 },
>>  ??????? ...
>>  ????}
>>
>>  ????struct of_device_id foo_of_match[] = {
>>  ??????? { .compatible = "foo,v1", .data = (void *)FOO_V1 },
>>  ??????? ...
>>  ????}
>>
>>  ????int foo_probe(struct device *dev) {
>>  ??????? ...
>>  ??????? foodev->version = (enum foo_ver)
>>  ??????????????? of_device_get_match_data(&dev->of_node)
>>  ??????? ...
>>  ????}
>>
>>  ????int foo_reset(struct foodev *foodev) {
>>  ??????? if (foodev->version == FOO_V1)
>>  ??????????? writel(0, foodev->base + 0x20);
>>  ??????? else
>>  ??????????? writel(0, foodev->base + 0x30);
>>  ????}
> 
> I did post v3 with this approach. However, I could not really find a ACPI function that
> returns the driver data very similar to of_device_get_match_data(). The only thing
> that is closer is acpi_match_device().

Yeah, I left the "follow the status quo and open-code it" part out of 
the above example for brevity ;)

Probably 95% of the calls to acpi_match_device() are only doing so to 
retrieve the driver_data, so the helper could provide scope for further 
cleanup if anyone wants, too.

> I introduced this new function as part of the v3 series.
> 
> Let me know if I'm missing something.
v3 looks good, thanks for persevering - I'll leave the rest up to Vinod 
and Rafael.

Cheers,
Robin.

[PATCH V2 3/3] dmaengine: qcom_hidma: add identity register support

[Sinan Kaya]

The location for destination event channel register has been relocated from
offset 0x28 to 0x40. Update the code accordingly.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
 drivers/dma/qcom/hidma.c | 33 ++++++++++++++++++++++++++++++++-
 1 file changed, 32 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/qcom/hidma.c b/drivers/dma/qcom/hidma.c
index 4ef7d6f..e8b7be0 100644
--- a/drivers/dma/qcom/hidma.c
+++ b/drivers/dma/qcom/hidma.c
@@ -126,6 +126,18 @@ struct hidma_cap {
 	}
 };
 
+static struct hidma_cap hidma_identity_cap = {
+	.of = {
+		{.compatible = "qcom,hidma-1.2",},
+		{},
+	},
+
+	.acpi = {
+		{"QCOM8063"},
+		{},
+	}
+};
+
 /* process completed descriptors */
 static void hidma_process_completed(struct hidma_chan *mchan)
 {
@@ -772,6 +784,22 @@ static bool hidma_msi_capable(struct device *dev)
 	return ret;
 }
 
+static bool hidma_identity_capable(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	int ret;
+
+	if (!adev || acpi_disabled)
+		ret = of_match_device(hidma_identity_cap.of, dev) != NULL;
+	else {
+#ifdef CONFIG_ACPI
+		ret = acpi_match_device(hidma_identity_cap.acpi, dev) != NULL;
+#endif
+	}
+
+	return ret;
+}
+
 static int hidma_probe(struct platform_device *pdev)
 {
 	struct hidma_dev *dmadev;
@@ -863,7 +891,10 @@ static int hidma_probe(struct platform_device *pdev)
 	if (!dmadev->nr_descriptors)
 		dmadev->nr_descriptors = HIDMA_NR_DEFAULT_DESC;
 
-	dmadev->chidx = readl(dmadev->dev_trca + 0x28);
+	if (hidma_identity_capable(&pdev->dev))
+		dmadev->chidx = readl(dmadev->dev_trca + 0x40);
+	else
+		dmadev->chidx = readl(dmadev->dev_trca + 0x28);
 
 	/* Set DMA mask to 64 bits. */
 	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
-- 
1.9.1