diff mbox series

[v2,1/4] staging/vc04_services: Use correct cache line size

Message ID 1536931375-48769-2-git-send-email-phil@raspberrypi.org (mailing list archive)
State Superseded, archived
Headers show
Series Improve VCHIQ cache line size handling | expand

Commit Message

Phil Elwell Sept. 14, 2018, 1:22 p.m. UTC
Use the compatible string in the DTB to select the correct cache line
size for the SoC - 32 for BCM2835, and 64 for BCM2836 and BCM2837.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
---
 .../interface/vchiq_arm/vchiq_2835_arm.c           |  4 ++-
 .../vc04_services/interface/vchiq_arm/vchiq_arm.c  | 36 ++++++++++++++++------
 .../vc04_services/interface/vchiq_arm/vchiq_arm.h  |  5 +++
 3 files changed, 34 insertions(+), 11 deletions(-)

Comments

Phil Elwell Sept. 14, 2018, 3:22 p.m. UTC | #1
On 14/09/2018 14:22, Phil Elwell wrote:
> Use the compatible string in the DTB to select the correct cache line
> size for the SoC - 32 for BCM2835, and 64 for BCM2836 and BCM2837.
> 
> Signed-off-by: Phil Elwell <phil@raspberrypi.org>
> ---
>   .../interface/vchiq_arm/vchiq_2835_arm.c           |  4 ++-
>   .../vc04_services/interface/vchiq_arm/vchiq_arm.c  | 36 ++++++++++++++++------
>   .../vc04_services/interface/vchiq_arm/vchiq_arm.h  |  5 +++
>   3 files changed, 34 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
> index e767209..83d740f 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
> @@ -109,7 +109,8 @@ free_pagelist(struct vchiq_pagelist_info *pagelistinfo,
>   int vchiq_platform_init(struct platform_device *pdev, VCHIQ_STATE_T *state)
>   {
>   	struct device *dev = &pdev->dev;
> -	struct rpi_firmware *fw = platform_get_drvdata(pdev);
> +	struct vchiq_drvdata *drvdata = platform_get_drvdata(pdev);
> +	struct rpi_firmware *fw = drvdata->fw;
>   	VCHIQ_SLOT_ZERO_T *vchiq_slot_zero;
>   	struct resource *res;
>   	void *slot_mem;
> @@ -127,6 +128,7 @@ int vchiq_platform_init(struct platform_device *pdev, VCHIQ_STATE_T *state)
>   	if (err < 0)
>   		return err;
>   
> +	g_cache_line_size = drvdata->cache_line_size;
>   	g_fragments_size = 2 * g_cache_line_size;
>   
>   	/* Allocate space for the channels in coherent memory */
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> index bc05c69..b2ae9259 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> @@ -170,6 +170,14 @@ static struct device *vchiq_dev;
>   static DEFINE_SPINLOCK(msg_queue_spinlock);
>   static struct platform_device *bcm2835_camera;
>   
> +static struct vchiq_drvdata bcm2835_drvdata = {
> +	.cache_line_size = 32,
> +};
> +
> +static struct vchiq_drvdata bcm2836_drvdata = {
> +	.cache_line_size = 64,
> +};
> +
>   static const char *const ioctl_names[] = {
>   	"CONNECT",
>   	"SHUTDOWN",
> @@ -3573,12 +3581,26 @@ void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
>   	}
>   }
>   
> +static const struct of_device_id vchiq_of_match[] = {
> +	{ .compatible = "brcm,bcm2835-vchiq", .data = &bcm2835_drvdata },
> +	{ .compatible = "brcm,bcm2836-vchiq", .data = &bcm2836_drvdata },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, vchiq_of_match);
> +
>   static int vchiq_probe(struct platform_device *pdev)
>   {
>   	struct device_node *fw_node;
> -	struct rpi_firmware *fw;
> +	const struct of_device_id *of_id;
> +	struct vchiq_drvdata *drvdata;
>   	int err;
>   
> +	snd_rpi_simple.dev = &pdev->dev;
> +	of_id = of_match_node(vchiq_of_match, pdev->dev.of_node);
> +	drvdata = of_id->data;
> +	if (!drvdata)
> +		return -EINVAL;
> +
>   	fw_node = of_find_compatible_node(NULL, NULL,
>   					  "raspberrypi,bcm2835-firmware");
>   	if (!fw_node) {
> @@ -3586,12 +3608,12 @@ static int vchiq_probe(struct platform_device *pdev)
>   		return -ENOENT;
>   	}
>   
> -	fw = rpi_firmware_get(fw_node);
> +	drvdata->fw = rpi_firmware_get(fw_node);
>   	of_node_put(fw_node);
> -	if (!fw)
> +	if (!drvdata->fw)
>   		return -EPROBE_DEFER;
>   
> -	platform_set_drvdata(pdev, fw);
> +	platform_set_drvdata(pdev, drvdata);
>   
>   	err = vchiq_platform_init(pdev, &g_state);
>   	if (err != 0)
> @@ -3661,12 +3683,6 @@ static int vchiq_remove(struct platform_device *pdev)
>   	return 0;
>   }
>   
> -static const struct of_device_id vchiq_of_match[] = {
> -	{ .compatible = "brcm,bcm2835-vchiq", },
> -	{},
> -};
> -MODULE_DEVICE_TABLE(of, vchiq_of_match);
> -
>   static struct platform_driver vchiq_driver = {
>   	.driver = {
>   		.name = "bcm2835_vchiq",
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> index 40bb0c6..2f3ebc9 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> @@ -123,6 +123,11 @@ typedef struct vchiq_arm_state_struct {
>   
>   } VCHIQ_ARM_STATE_T;
>   
> +struct vchiq_drvdata {
> +	const unsigned int cache_line_size;
> +	struct rpi_firmware *fw;
> +};
> +
>   extern int vchiq_arm_log_level;
>   extern int vchiq_susp_log_level;
>   
> 

This version doesn't compile (wrong defconfig used when building), but any criticism of the
approach before v3 is welcome.

Phil
Stefan Wahren Sept. 14, 2018, 4:46 p.m. UTC | #2
Hi Phil,

> Phil Elwell <phil@raspberrypi.org> hat am 14. September 2018 um 17:22 geschrieben:
> 
> 
> On 14/09/2018 14:22, Phil Elwell wrote:
> > Use the compatible string in the DTB to select the correct cache line
> > size for the SoC - 32 for BCM2835, and 64 for BCM2836 and BCM2837.
> > 
> > Signed-off-by: Phil Elwell <phil@raspberrypi.org>
> > ---
> >   .../interface/vchiq_arm/vchiq_2835_arm.c           |  4 ++-
> >   .../vc04_services/interface/vchiq_arm/vchiq_arm.c  | 36 ++++++++++++++++------
> >   .../vc04_services/interface/vchiq_arm/vchiq_arm.h  |  5 +++
> >   3 files changed, 34 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
> > index e767209..83d740f 100644
> > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
> > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
> > @@ -109,7 +109,8 @@ free_pagelist(struct vchiq_pagelist_info *pagelistinfo,
> >   int vchiq_platform_init(struct platform_device *pdev, VCHIQ_STATE_T *state)
> >   {
> >   	struct device *dev = &pdev->dev;
> > -	struct rpi_firmware *fw = platform_get_drvdata(pdev);
> > +	struct vchiq_drvdata *drvdata = platform_get_drvdata(pdev);
> > +	struct rpi_firmware *fw = drvdata->fw;
> >   	VCHIQ_SLOT_ZERO_T *vchiq_slot_zero;
> >   	struct resource *res;
> >   	void *slot_mem;
> > @@ -127,6 +128,7 @@ int vchiq_platform_init(struct platform_device *pdev, VCHIQ_STATE_T *state)
> >   	if (err < 0)
> >   		return err;
> >   
> > +	g_cache_line_size = drvdata->cache_line_size;
> >   	g_fragments_size = 2 * g_cache_line_size;
> >   
> >   	/* Allocate space for the channels in coherent memory */
> > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> > index bc05c69..b2ae9259 100644
> > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> > @@ -170,6 +170,14 @@ static struct device *vchiq_dev;
> >   static DEFINE_SPINLOCK(msg_queue_spinlock);
> >   static struct platform_device *bcm2835_camera;
> >   
> > +static struct vchiq_drvdata bcm2835_drvdata = {
> > +	.cache_line_size = 32,
> > +};
> > +
> > +static struct vchiq_drvdata bcm2836_drvdata = {
> > +	.cache_line_size = 64,
> > +};
> > +
> >   static const char *const ioctl_names[] = {
> >   	"CONNECT",
> >   	"SHUTDOWN",
> > @@ -3573,12 +3581,26 @@ void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
> >   	}
> >   }
> >   
> > +static const struct of_device_id vchiq_of_match[] = {
> > +	{ .compatible = "brcm,bcm2835-vchiq", .data = &bcm2835_drvdata },
> > +	{ .compatible = "brcm,bcm2836-vchiq", .data = &bcm2836_drvdata },
> > +	{},
> > +};
> > +MODULE_DEVICE_TABLE(of, vchiq_of_match);
> > +
> >   static int vchiq_probe(struct platform_device *pdev)
> >   {
> >   	struct device_node *fw_node;
> > -	struct rpi_firmware *fw;
> > +	const struct of_device_id *of_id;
> > +	struct vchiq_drvdata *drvdata;
> >   	int err;
> >   
> > +	snd_rpi_simple.dev = &pdev->dev;
> > +	of_id = of_match_node(vchiq_of_match, pdev->dev.of_node);
> > +	drvdata = of_id->data;
> > +	if (!drvdata)
> > +		return -EINVAL;
> > +
> >   	fw_node = of_find_compatible_node(NULL, NULL,
> >   					  "raspberrypi,bcm2835-firmware");
> >   	if (!fw_node) {
> > @@ -3586,12 +3608,12 @@ static int vchiq_probe(struct platform_device *pdev)
> >   		return -ENOENT;
> >   	}
> >   
> > -	fw = rpi_firmware_get(fw_node);
> > +	drvdata->fw = rpi_firmware_get(fw_node);
> >   	of_node_put(fw_node);
> > -	if (!fw)
> > +	if (!drvdata->fw)
> >   		return -EPROBE_DEFER;
> >   
> > -	platform_set_drvdata(pdev, fw);
> > +	platform_set_drvdata(pdev, drvdata);
> >   
> >   	err = vchiq_platform_init(pdev, &g_state);
> >   	if (err != 0)
> > @@ -3661,12 +3683,6 @@ static int vchiq_remove(struct platform_device *pdev)
> >   	return 0;
> >   }
> >   
> > -static const struct of_device_id vchiq_of_match[] = {
> > -	{ .compatible = "brcm,bcm2835-vchiq", },
> > -	{},
> > -};
> > -MODULE_DEVICE_TABLE(of, vchiq_of_match);
> > -
> >   static struct platform_driver vchiq_driver = {
> >   	.driver = {
> >   		.name = "bcm2835_vchiq",
> > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> > index 40bb0c6..2f3ebc9 100644
> > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> > @@ -123,6 +123,11 @@ typedef struct vchiq_arm_state_struct {
> >   
> >   } VCHIQ_ARM_STATE_T;
> >   
> > +struct vchiq_drvdata {
> > +	const unsigned int cache_line_size;
> > +	struct rpi_firmware *fw;
> > +};
> > +
> >   extern int vchiq_arm_log_level;
> >   extern int vchiq_susp_log_level;
> >   
> > 
> 
> This version doesn't compile (wrong defconfig used when building), but any criticism of the
> approach before v3 is welcome.

no need to hurry, my pull requests for 4.20 are already out. Please take the time to test this properly.

Patch 2-4 are:

Acked-by: Stefan Wahren <stefan.wahren@i2se.com>

> 
> Phil
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Florian Fainelli Sept. 14, 2018, 5:03 p.m. UTC | #3
On 09/14/2018 06:22 AM, Phil Elwell wrote:
> Use the compatible string in the DTB to select the correct cache line
> size for the SoC - 32 for BCM2835, and 64 for BCM2836 and BCM2837.
> 
> Signed-off-by: Phil Elwell <phil@raspberrypi.org>
> ---

[snip]

> @@ -170,6 +170,14 @@ static struct device *vchiq_dev;
>  static DEFINE_SPINLOCK(msg_queue_spinlock);
>  static struct platform_device *bcm2835_camera;
>  
> +static struct vchiq_drvdata bcm2835_drvdata = {
> +	.cache_line_size = 32,
> +};
> +
> +static struct vchiq_drvdata bcm2836_drvdata = {
> +	.cache_line_size = 64,
> +};

Those two structures could probably be marked const. Other than that,
the approach definitively looks good to me.
Phil Elwell Sept. 14, 2018, 6:12 p.m. UTC | #4
On 14/09/2018 18:03, Florian Fainelli wrote:
> On 09/14/2018 06:22 AM, Phil Elwell wrote:
>> Use the compatible string in the DTB to select the correct cache line
>> size for the SoC - 32 for BCM2835, and 64 for BCM2836 and BCM2837.
>>
>> Signed-off-by: Phil Elwell <phil@raspberrypi.org>
>> ---
> 
> [snip]
> 
>> @@ -170,6 +170,14 @@ static struct device *vchiq_dev;
>>   static DEFINE_SPINLOCK(msg_queue_spinlock);
>>   static struct platform_device *bcm2835_camera;
>>   
>> +static struct vchiq_drvdata bcm2835_drvdata = {
>> +	.cache_line_size = 32,
>> +};
>> +
>> +static struct vchiq_drvdata bcm2836_drvdata = {
>> +	.cache_line_size = 64,
>> +};
> 
> Those two structures could probably be marked const. Other than that,
> the approach definitively looks good to me.

The mutability is intentional - the structure pointer to the firmware is also
stored there. This isn't the only piece of mutable static data in a driver
that will only have a single instance, so allocating and initialising a
per-instance structure seems needlessly complicated.

Thanks for the feedback.

Phil
Florian Fainelli Sept. 14, 2018, 6:20 p.m. UTC | #5
On 09/14/2018 11:12 AM, Phil Elwell wrote:
> On 14/09/2018 18:03, Florian Fainelli wrote:
>> On 09/14/2018 06:22 AM, Phil Elwell wrote:
>>> Use the compatible string in the DTB to select the correct cache line
>>> size for the SoC - 32 for BCM2835, and 64 for BCM2836 and BCM2837.
>>>
>>> Signed-off-by: Phil Elwell <phil@raspberrypi.org>
>>> ---
>>
>> [snip]
>>
>>> @@ -170,6 +170,14 @@ static struct device *vchiq_dev;
>>>   static DEFINE_SPINLOCK(msg_queue_spinlock);
>>>   static struct platform_device *bcm2835_camera;
>>>   +static struct vchiq_drvdata bcm2835_drvdata = {
>>> +    .cache_line_size = 32,
>>> +};
>>> +
>>> +static struct vchiq_drvdata bcm2836_drvdata = {
>>> +    .cache_line_size = 64,
>>> +};
>>
>> Those two structures could probably be marked const. Other than that,
>> the approach definitively looks good to me.
> 
> The mutability is intentional - the structure pointer to the firmware is
> also
> stored there. This isn't the only piece of mutable static data in a driver
> that will only have a single instance, so allocating and initialising a
> per-instance structure seems needlessly complicated.

Fair enough, thanks for the explanation.
diff mbox series

Patch

diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
index e767209..83d740f 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_2835_arm.c
@@ -109,7 +109,8 @@  free_pagelist(struct vchiq_pagelist_info *pagelistinfo,
 int vchiq_platform_init(struct platform_device *pdev, VCHIQ_STATE_T *state)
 {
 	struct device *dev = &pdev->dev;
-	struct rpi_firmware *fw = platform_get_drvdata(pdev);
+	struct vchiq_drvdata *drvdata = platform_get_drvdata(pdev);
+	struct rpi_firmware *fw = drvdata->fw;
 	VCHIQ_SLOT_ZERO_T *vchiq_slot_zero;
 	struct resource *res;
 	void *slot_mem;
@@ -127,6 +128,7 @@  int vchiq_platform_init(struct platform_device *pdev, VCHIQ_STATE_T *state)
 	if (err < 0)
 		return err;
 
+	g_cache_line_size = drvdata->cache_line_size;
 	g_fragments_size = 2 * g_cache_line_size;
 
 	/* Allocate space for the channels in coherent memory */
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index bc05c69..b2ae9259 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -170,6 +170,14 @@  static struct device *vchiq_dev;
 static DEFINE_SPINLOCK(msg_queue_spinlock);
 static struct platform_device *bcm2835_camera;
 
+static struct vchiq_drvdata bcm2835_drvdata = {
+	.cache_line_size = 32,
+};
+
+static struct vchiq_drvdata bcm2836_drvdata = {
+	.cache_line_size = 64,
+};
+
 static const char *const ioctl_names[] = {
 	"CONNECT",
 	"SHUTDOWN",
@@ -3573,12 +3581,26 @@  void vchiq_platform_conn_state_changed(VCHIQ_STATE_T *state,
 	}
 }
 
+static const struct of_device_id vchiq_of_match[] = {
+	{ .compatible = "brcm,bcm2835-vchiq", .data = &bcm2835_drvdata },
+	{ .compatible = "brcm,bcm2836-vchiq", .data = &bcm2836_drvdata },
+	{},
+};
+MODULE_DEVICE_TABLE(of, vchiq_of_match);
+
 static int vchiq_probe(struct platform_device *pdev)
 {
 	struct device_node *fw_node;
-	struct rpi_firmware *fw;
+	const struct of_device_id *of_id;
+	struct vchiq_drvdata *drvdata;
 	int err;
 
+	snd_rpi_simple.dev = &pdev->dev;
+	of_id = of_match_node(vchiq_of_match, pdev->dev.of_node);
+	drvdata = of_id->data;
+	if (!drvdata)
+		return -EINVAL;
+
 	fw_node = of_find_compatible_node(NULL, NULL,
 					  "raspberrypi,bcm2835-firmware");
 	if (!fw_node) {
@@ -3586,12 +3608,12 @@  static int vchiq_probe(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
-	fw = rpi_firmware_get(fw_node);
+	drvdata->fw = rpi_firmware_get(fw_node);
 	of_node_put(fw_node);
-	if (!fw)
+	if (!drvdata->fw)
 		return -EPROBE_DEFER;
 
-	platform_set_drvdata(pdev, fw);
+	platform_set_drvdata(pdev, drvdata);
 
 	err = vchiq_platform_init(pdev, &g_state);
 	if (err != 0)
@@ -3661,12 +3683,6 @@  static int vchiq_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id vchiq_of_match[] = {
-	{ .compatible = "brcm,bcm2835-vchiq", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, vchiq_of_match);
-
 static struct platform_driver vchiq_driver = {
 	.driver = {
 		.name = "bcm2835_vchiq",
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
index 40bb0c6..2f3ebc9 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
@@ -123,6 +123,11 @@  typedef struct vchiq_arm_state_struct {
 
 } VCHIQ_ARM_STATE_T;
 
+struct vchiq_drvdata {
+	const unsigned int cache_line_size;
+	struct rpi_firmware *fw;
+};
+
 extern int vchiq_arm_log_level;
 extern int vchiq_susp_log_level;