diff mbox

[v1,6/6] rpmsg: virtio_rpmsg: set buffer configuration to virtio

Message ID 1481142941-15616-7-git-send-email-loic.pallardy@st.com (mailing list archive)
State Superseded
Headers show

Commit Message

Loic PALLARDY Dec. 7, 2016, 8:35 p.m. UTC
Rpmsg is allocating buffer one dedicated communication link
with some specificity like number of buffers, size of one buffer...
These characteristics should be shared with remote coprocessor to
guarantee communication link coherency.

Proposal is to update rpmsg configuration fields in coprocessor firmware
resource table if it exists.

This is possible thanks to virtio set interface which allows to update
cfg fields of struct fw_rsc_vdev.

Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
---
 drivers/rpmsg/virtio_rpmsg_bus.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

Comments

Suman Anna Jan. 14, 2017, 2:41 a.m. UTC | #1
On 12/07/2016 02:35 PM, Loic Pallardy wrote:
> Rpmsg is allocating buffer one dedicated communication link
> with some specificity like number of buffers, size of one buffer...
> These characteristics should be shared with remote coprocessor to
> guarantee communication link coherency.
> 
> Proposal is to update rpmsg configuration fields in coprocessor firmware
> resource table if it exists.
> 
> This is possible thanks to virtio set interface which allows to update
> cfg fields of struct fw_rsc_vdev.
> 
> Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
> ---
>  drivers/rpmsg/virtio_rpmsg_bus.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
> index b12fe2a..5527b65 100644
> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> @@ -924,6 +924,23 @@ static int virtio_rpmsg_get_config(struct virtio_device *vdev)
>  
>  }
>  
> +static void virtio_rpmsg_set_config(struct virtio_device *vdev)
> +{
> +	struct virtio_rpmsg_cfg virtio_cfg;
> +	struct virtproc_info *vrp = vdev->priv;
> +
> +	/* fill virtio_cfg struct */
> +	memset(&virtio_cfg, 0, sizeof(virtio_cfg));
> +	virtio_cfg.id = VIRTIO_ID_RPMSG;
> +	virtio_cfg.da = vrp->bufs_dma;

Hmm, I would expect this to fail if the device was behind an IOMMU.

regards
Suman

> +	virtio_cfg.pa =	vrp->bufs_dma;
> +	virtio_cfg.len = vrp->num_bufs * vrp->buf_size;
> +	virtio_cfg.buf_size = vrp->buf_size;
> +
> +	vdev->config->set(vdev, RPMSG_CONFIG_OFFSET, &virtio_cfg,
> +			  sizeof(virtio_cfg));
> +}
> +
>  static int rpmsg_probe(struct virtio_device *vdev)
>  {
>  	vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
> @@ -934,6 +951,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  	int err = 0, i;
>  	size_t total_buf_space;
>  	bool notify;
> +	bool has_cfg = false;
>  
>  	vrp = kzalloc(sizeof(*vrp), GFP_KERNEL);
>  	if (!vrp)
> @@ -973,6 +991,9 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  	if (err < 0)
>  		goto free_vrp;
>  
> +	if (err)
> +		has_cfg = true;
> +
>  	/* Allocate buffer if none provided by low level platform driver */
>  	if (!vrp->ext_buffer) {
>  		total_buf_space = vrp->num_bufs * vrp->buf_size;
> @@ -993,6 +1014,10 @@ static int rpmsg_probe(struct virtio_device *vdev)
>  
>  		/* and half is dedicated for TX */
>  		vrp->sbufs = bufs_va + total_buf_space / 2;
> +
> +		/* Notify configuration to coprocessor */
> +		if (has_cfg)
> +			virtio_rpmsg_set_config(vdev);
>  	}
>  
>  	/* set up the receive buffers */
> 

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Loic PALLARDY Jan. 14, 2017, 7:36 p.m. UTC | #2
> -----Original Message-----
> From: Suman Anna [mailto:s-anna@ti.com]
> Sent: Saturday, January 14, 2017 3:41 AM
> To: Loic PALLARDY <loic.pallardy@st.com>; bjorn.andersson@linaro.org;
> ohad@wizery.com; lee.jones@linaro.org; Patrice CHOTARD
> <patrice.chotard@st.com>
> Cc: linux-remoteproc@vger.kernel.org; kernel@stlinux.com
> Subject: Re: [PATCH v1 6/6] rpmsg: virtio_rpmsg: set buffer configuration to
> virtio
> 
> On 12/07/2016 02:35 PM, Loic Pallardy wrote:
> > Rpmsg is allocating buffer one dedicated communication link with some
> > specificity like number of buffers, size of one buffer...
> > These characteristics should be shared with remote coprocessor to
> > guarantee communication link coherency.
> >
> > Proposal is to update rpmsg configuration fields in coprocessor
> > firmware resource table if it exists.
> >
> > This is possible thanks to virtio set interface which allows to update
> > cfg fields of struct fw_rsc_vdev.
> >
> > Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
> > ---
> >  drivers/rpmsg/virtio_rpmsg_bus.c | 25 +++++++++++++++++++++++++
> >  1 file changed, 25 insertions(+)
> >
> > diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c
> > b/drivers/rpmsg/virtio_rpmsg_bus.c
> > index b12fe2a..5527b65 100644
> > --- a/drivers/rpmsg/virtio_rpmsg_bus.c
> > +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
> > @@ -924,6 +924,23 @@ static int virtio_rpmsg_get_config(struct
> > virtio_device *vdev)
> >
> >  }
> >
> > +static void virtio_rpmsg_set_config(struct virtio_device *vdev) {
> > +	struct virtio_rpmsg_cfg virtio_cfg;
> > +	struct virtproc_info *vrp = vdev->priv;
> > +
> > +	/* fill virtio_cfg struct */
> > +	memset(&virtio_cfg, 0, sizeof(virtio_cfg));
> > +	virtio_cfg.id = VIRTIO_ID_RPMSG;
> > +	virtio_cfg.da = vrp->bufs_dma;
> 
> Hmm, I would expect this to fail if the device was behind an IOMMU.
I think so. I think I did the same vring. I need to check.
Perhaps better to set virtio_cfg.da to ANY_ADDRESS (-1) and add a comment about adding IOMMU support.
What do you think?

Regards,
Loic
> 
> regards
> Suman
> 
> > +	virtio_cfg.pa =	vrp->bufs_dma;
> > +	virtio_cfg.len = vrp->num_bufs * vrp->buf_size;
> > +	virtio_cfg.buf_size = vrp->buf_size;
> > +
> > +	vdev->config->set(vdev, RPMSG_CONFIG_OFFSET, &virtio_cfg,
> > +			  sizeof(virtio_cfg));
> > +}
> > +
> >  static int rpmsg_probe(struct virtio_device *vdev)  {
> >  	vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
> @@
> > -934,6 +951,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
> >  	int err = 0, i;
> >  	size_t total_buf_space;
> >  	bool notify;
> > +	bool has_cfg = false;
> >
> >  	vrp = kzalloc(sizeof(*vrp), GFP_KERNEL);
> >  	if (!vrp)
> > @@ -973,6 +991,9 @@ static int rpmsg_probe(struct virtio_device *vdev)
> >  	if (err < 0)
> >  		goto free_vrp;
> >
> > +	if (err)
> > +		has_cfg = true;
> > +
> >  	/* Allocate buffer if none provided by low level platform driver */
> >  	if (!vrp->ext_buffer) {
> >  		total_buf_space = vrp->num_bufs * vrp->buf_size; @@ -
> 993,6 +1014,10
> > @@ static int rpmsg_probe(struct virtio_device *vdev)
> >
> >  		/* and half is dedicated for TX */
> >  		vrp->sbufs = bufs_va + total_buf_space / 2;
> > +
> > +		/* Notify configuration to coprocessor */
> > +		if (has_cfg)
> > +			virtio_rpmsg_set_config(vdev);
> >  	}
> >
> >  	/* set up the receive buffers */
> >

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Suman Anna Jan. 16, 2017, 3:59 p.m. UTC | #3
On 01/14/2017 01:36 PM, Loic PALLARDY wrote:
> 
> 
>> -----Original Message-----
>> From: Suman Anna [mailto:s-anna@ti.com]
>> Sent: Saturday, January 14, 2017 3:41 AM
>> To: Loic PALLARDY <loic.pallardy@st.com>; bjorn.andersson@linaro.org;
>> ohad@wizery.com; lee.jones@linaro.org; Patrice CHOTARD
>> <patrice.chotard@st.com>
>> Cc: linux-remoteproc@vger.kernel.org; kernel@stlinux.com
>> Subject: Re: [PATCH v1 6/6] rpmsg: virtio_rpmsg: set buffer configuration to
>> virtio
>>
>> On 12/07/2016 02:35 PM, Loic Pallardy wrote:
>>> Rpmsg is allocating buffer one dedicated communication link with some
>>> specificity like number of buffers, size of one buffer...
>>> These characteristics should be shared with remote coprocessor to
>>> guarantee communication link coherency.
>>>
>>> Proposal is to update rpmsg configuration fields in coprocessor
>>> firmware resource table if it exists.
>>>
>>> This is possible thanks to virtio set interface which allows to update
>>> cfg fields of struct fw_rsc_vdev.
>>>
>>> Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
>>> ---
>>>  drivers/rpmsg/virtio_rpmsg_bus.c | 25 +++++++++++++++++++++++++
>>>  1 file changed, 25 insertions(+)
>>>
>>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c
>>> b/drivers/rpmsg/virtio_rpmsg_bus.c
>>> index b12fe2a..5527b65 100644
>>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c
>>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c
>>> @@ -924,6 +924,23 @@ static int virtio_rpmsg_get_config(struct
>>> virtio_device *vdev)
>>>
>>>  }
>>>
>>> +static void virtio_rpmsg_set_config(struct virtio_device *vdev) {
>>> +	struct virtio_rpmsg_cfg virtio_cfg;
>>> +	struct virtproc_info *vrp = vdev->priv;
>>> +
>>> +	/* fill virtio_cfg struct */
>>> +	memset(&virtio_cfg, 0, sizeof(virtio_cfg));
>>> +	virtio_cfg.id = VIRTIO_ID_RPMSG;
>>> +	virtio_cfg.da = vrp->bufs_dma;
>>
>> Hmm, I would expect this to fail if the device was behind an IOMMU.
> I think so. I think I did the same vring. I need to check.
> Perhaps better to set virtio_cfg.da to ANY_ADDRESS (-1) and add a comment about adding IOMMU support.
> What do you think?

Yeah, that is a better interim change.

regards
Suman

> 
> Regards,
> Loic
>>
>> regards
>> Suman
>>
>>> +	virtio_cfg.pa =	vrp->bufs_dma;
>>> +	virtio_cfg.len = vrp->num_bufs * vrp->buf_size;
>>> +	virtio_cfg.buf_size = vrp->buf_size;
>>> +
>>> +	vdev->config->set(vdev, RPMSG_CONFIG_OFFSET, &virtio_cfg,
>>> +			  sizeof(virtio_cfg));
>>> +}
>>> +
>>>  static int rpmsg_probe(struct virtio_device *vdev)  {
>>>  	vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
>> @@
>>> -934,6 +951,7 @@ static int rpmsg_probe(struct virtio_device *vdev)
>>>  	int err = 0, i;
>>>  	size_t total_buf_space;
>>>  	bool notify;
>>> +	bool has_cfg = false;
>>>
>>>  	vrp = kzalloc(sizeof(*vrp), GFP_KERNEL);
>>>  	if (!vrp)
>>> @@ -973,6 +991,9 @@ static int rpmsg_probe(struct virtio_device *vdev)
>>>  	if (err < 0)
>>>  		goto free_vrp;
>>>
>>> +	if (err)
>>> +		has_cfg = true;
>>> +
>>>  	/* Allocate buffer if none provided by low level platform driver */
>>>  	if (!vrp->ext_buffer) {
>>>  		total_buf_space = vrp->num_bufs * vrp->buf_size; @@ -
>> 993,6 +1014,10
>>> @@ static int rpmsg_probe(struct virtio_device *vdev)
>>>
>>>  		/* and half is dedicated for TX */
>>>  		vrp->sbufs = bufs_va + total_buf_space / 2;
>>> +
>>> +		/* Notify configuration to coprocessor */
>>> +		if (has_cfg)
>>> +			virtio_rpmsg_set_config(vdev);
>>>  	}
>>>
>>>  	/* set up the receive buffers */
>>>
> 

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diff mbox

Patch

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index b12fe2a..5527b65 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -924,6 +924,23 @@  static int virtio_rpmsg_get_config(struct virtio_device *vdev)
 
 }
 
+static void virtio_rpmsg_set_config(struct virtio_device *vdev)
+{
+	struct virtio_rpmsg_cfg virtio_cfg;
+	struct virtproc_info *vrp = vdev->priv;
+
+	/* fill virtio_cfg struct */
+	memset(&virtio_cfg, 0, sizeof(virtio_cfg));
+	virtio_cfg.id = VIRTIO_ID_RPMSG;
+	virtio_cfg.da = vrp->bufs_dma;
+	virtio_cfg.pa =	vrp->bufs_dma;
+	virtio_cfg.len = vrp->num_bufs * vrp->buf_size;
+	virtio_cfg.buf_size = vrp->buf_size;
+
+	vdev->config->set(vdev, RPMSG_CONFIG_OFFSET, &virtio_cfg,
+			  sizeof(virtio_cfg));
+}
+
 static int rpmsg_probe(struct virtio_device *vdev)
 {
 	vq_callback_t *vq_cbs[] = { rpmsg_recv_done, rpmsg_xmit_done };
@@ -934,6 +951,7 @@  static int rpmsg_probe(struct virtio_device *vdev)
 	int err = 0, i;
 	size_t total_buf_space;
 	bool notify;
+	bool has_cfg = false;
 
 	vrp = kzalloc(sizeof(*vrp), GFP_KERNEL);
 	if (!vrp)
@@ -973,6 +991,9 @@  static int rpmsg_probe(struct virtio_device *vdev)
 	if (err < 0)
 		goto free_vrp;
 
+	if (err)
+		has_cfg = true;
+
 	/* Allocate buffer if none provided by low level platform driver */
 	if (!vrp->ext_buffer) {
 		total_buf_space = vrp->num_bufs * vrp->buf_size;
@@ -993,6 +1014,10 @@  static int rpmsg_probe(struct virtio_device *vdev)
 
 		/* and half is dedicated for TX */
 		vrp->sbufs = bufs_va + total_buf_space / 2;
+
+		/* Notify configuration to coprocessor */
+		if (has_cfg)
+			virtio_rpmsg_set_config(vdev);
 	}
 
 	/* set up the receive buffers */