diff mbox series

[v5,1/7] mei: bus: add client dma interface

Message ID 20210727065134.3902-1-emmanuel.grumbach@intel.com
State Superseded
Headers show
Series [v5,1/7] mei: bus: add client dma interface | expand

Commit Message

Emmanuel Grumbach July 27, 2021, 6:51 a.m. UTC 
From: Alexander Usyskin <alexander.usyskin@intel.com>

Expose the client dma mapping via mei client bus interface.
The client dma has to be mapped before the device is enabled,
therefore we need to create device linking already during mapping
and we need to unmap after the client is disable hence we need to
postpone the unlink and flush till unmapping or when
destroying the device.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Co-developed-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210420172755.12178-1-emmanuel.grumbach@intel.com
---
 drivers/misc/mei/bus.c     | 67 ++++++++++++++++++++++++++++++++++++--
 drivers/misc/mei/client.c  |  3 ++
 drivers/misc/mei/hw.h      |  5 +++
 include/linux/mei_cl_bus.h |  3 ++
 4 files changed, 75 insertions(+), 3 deletions(-)

Comments

Emmanuel Grumbach Aug. 2, 2021, 6:33 p.m. UTC | #1 
Hi Kalle,

> 

> From: Alexander Usyskin <alexander.usyskin@intel.com>

> 

> Expose the client dma mapping via mei client bus interface.

> The client dma has to be mapped before the device is enabled, therefore we

> need to create device linking already during mapping and we need to unmap

> after the client is disable hence we need to postpone the unlink and flush till

> unmapping or when destroying the device.

> 

> Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>

> Co-developed-by: Tomas Winkler <tomas.winkler@intel.com>

> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>

> Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

> Link: https://lore.kernel.org/r/20210420172755.12178-1-

> emmanuel.grumbach@intel.com

> ---


This series is assigned to Luca on patchwork besides this patch and the one with
the vendor commands which are assigned to Johannes.
I am a bit confused because you seemed to say you want to look at them, so maybe
they should be assigned to you?
Moreover the vendor commands patch is meant to be routed through the drivers'
tree.

Thank you.
Coelho, Luciano Aug. 2, 2021, 6:54 p.m. UTC | #2 
On Mon, 2021-08-02 at 18:33 +0000, Grumbach, Emmanuel wrote:
> Hi Kalle,

> 

> > 

> > From: Alexander Usyskin <alexander.usyskin@intel.com>

> > 

> > Expose the client dma mapping via mei client bus interface.

> > The client dma has to be mapped before the device is enabled, therefore we

> > need to create device linking already during mapping and we need to unmap

> > after the client is disable hence we need to postpone the unlink and flush till

> > unmapping or when destroying the device.

> > 

> > Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>

> > Co-developed-by: Tomas Winkler <tomas.winkler@intel.com>

> > Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>

> > Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

> > Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

> > Link: https://lore.kernel.org/r/20210420172755.12178-1-

> > emmanuel.grumbach@intel.com

> > ---

> 

> This series is assigned to Luca on patchwork besides this patch and the one with

> the vendor commands which are assigned to Johannes.

> I am a bit confused because you seemed to say you want to look at them, so maybe

> they should be assigned to you?

> Moreover the vendor commands patch is meant to be routed through the drivers'

> tree.


Emmanuel, the assignment is done automatically depending on the files
changed.

Since Kalle earlier said that he wants to review and apply these
patches directly to his tree, I'll assign the entire series to him now.

--
Cheers,
Luca.
diff mbox series

Patch

diff --git a/drivers/misc/mei/bus.c b/drivers/misc/mei/bus.c
index 935acc6bbf3c..7a325572ad1d 100644
--- a/drivers/misc/mei/bus.c
+++ b/drivers/misc/mei/bus.c
@@ -643,6 +643,64 @@  static void mei_cl_bus_vtag_free(struct mei_cl_device *cldev)
 	kfree(cl_vtag);
 }
 
+void *mei_cldev_dma_map(struct mei_cl_device *cldev, u8 buffer_id, size_t size)
+{
+	struct mei_device *bus;
+	struct mei_cl *cl;
+	int ret;
+
+	if (!cldev || !buffer_id || !size)
+		return ERR_PTR(-EINVAL);
+
+	if (!IS_ALIGNED(size, MEI_FW_PAGE_SIZE)) {
+		dev_err(&cldev->dev, "Map size should be aligned to %lu\n",
+			MEI_FW_PAGE_SIZE);
+		return ERR_PTR(-EINVAL);
+	}
+
+	cl = cldev->cl;
+	bus = cldev->bus;
+
+	mutex_lock(&bus->device_lock);
+	if (cl->state == MEI_FILE_UNINITIALIZED) {
+		ret = mei_cl_link(cl);
+		if (ret)
+			goto out;
+		/* update pointers */
+		cl->cldev = cldev;
+	}
+
+	ret = mei_cl_dma_alloc_and_map(cl, NULL, buffer_id, size);
+out:
+	mutex_unlock(&bus->device_lock);
+	if (ret)
+		return ERR_PTR(ret);
+	return cl->dma.vaddr;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_dma_map);
+
+int mei_cldev_dma_unmap(struct mei_cl_device *cldev)
+{
+	struct mei_device *bus;
+	struct mei_cl *cl;
+	int ret;
+
+	if (!cldev)
+		return -EINVAL;
+
+	cl = cldev->cl;
+	bus = cldev->bus;
+
+	mutex_lock(&bus->device_lock);
+	ret = mei_cl_dma_unmap(cl, NULL);
+
+	mei_cl_flush_queues(cl, NULL);
+	mei_cl_unlink(cl);
+	mutex_unlock(&bus->device_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(mei_cldev_dma_unmap);
+
 /**
  * mei_cldev_enable - enable me client device
  *     create connection with me client
@@ -753,9 +811,11 @@  int mei_cldev_disable(struct mei_cl_device *cldev)
 		dev_err(bus->dev, "Could not disconnect from the ME client\n");
 
 out:
-	/* Flush queues and remove any pending read */
-	mei_cl_flush_queues(cl, NULL);
-	mei_cl_unlink(cl);
+	/* Flush queues and remove any pending read unless we have mapped DMA */
+	if (!cl->dma_mapped) {
+		mei_cl_flush_queues(cl, NULL);
+		mei_cl_unlink(cl);
+	}
 
 	mutex_unlock(&bus->device_lock);
 	return err;
@@ -1054,6 +1114,7 @@  static void mei_cl_bus_dev_release(struct device *dev)
 	if (!cldev)
 		return;
 
+	mei_cl_flush_queues(cldev->cl, NULL);
 	mei_me_cl_put(cldev->me_cl);
 	mei_dev_bus_put(cldev->bus);
 	mei_cl_unlink(cldev->cl);
diff --git a/drivers/misc/mei/client.c b/drivers/misc/mei/client.c
index 96f4e59c32a5..0e90591235a6 100644
--- a/drivers/misc/mei/client.c
+++ b/drivers/misc/mei/client.c
@@ -700,6 +700,9 @@  int mei_cl_unlink(struct mei_cl *cl)
 
 	cl_dbg(dev, cl, "unlink client");
 
+	if (cl->state == MEI_FILE_UNINITIALIZED)
+		return 0;
+
 	if (dev->open_handle_count > 0)
 		dev->open_handle_count--;
 
diff --git a/drivers/misc/mei/hw.h b/drivers/misc/mei/hw.h
index dfd60c916da0..b46077b17114 100644
--- a/drivers/misc/mei/hw.h
+++ b/drivers/misc/mei/hw.h
@@ -22,6 +22,11 @@ 
 #define MEI_D0I3_TIMEOUT            5  /* D0i3 set/unset max response time */
 #define MEI_HBM_TIMEOUT             1  /* 1 second */
 
+/*
+ * FW page size for DMA allocations
+ */
+#define MEI_FW_PAGE_SIZE 4096UL
+
 /*
  * MEI Version
  */
diff --git a/include/linux/mei_cl_bus.h b/include/linux/mei_cl_bus.h
index 07f5ef8fc456..8c8d46ba33bf 100644
--- a/include/linux/mei_cl_bus.h
+++ b/include/linux/mei_cl_bus.h
@@ -116,4 +116,7 @@  int mei_cldev_enable(struct mei_cl_device *cldev);
 int mei_cldev_disable(struct mei_cl_device *cldev);
 bool mei_cldev_enabled(struct mei_cl_device *cldev);
 
+void *mei_cldev_dma_map(struct mei_cl_device *cldev, u8 buffer_id, size_t size);
+int mei_cldev_dma_unmap(struct mei_cl_device *cldev);
+
 #endif /* _LINUX_MEI_CL_BUS_H */