diff mbox

[05/15] cxl: Allow a default context to be associated with an external pci_dev

Message ID 1468237822-26276-6-git-send-email-imunsie@au.ibm.com (mailing list archive)
State Superseded
Headers show

Commit Message

Ian Munsie July 11, 2016, 11:50 a.m. UTC 
From: Ian Munsie <imunsie@au1.ibm.com>

The cxl kernel API has a concept of a default context associated with
each PCI device under the virtual PHB. The Mellanox CX4 will also use
the cxl kernel API, but it does not use a virtual PHB - rather, the AFU
appears as a physical function as a peer to the networking functions.

In order to allow the kernel API to work with those networking
functions, we will need to associate a default context with them as
well. To this end, refactor the corresponding code to do this in vphb.c
and export it so that it can be called from the PHB code.

Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
---
 drivers/misc/cxl/base.c | 35 +++++++++++++++++++++++++++++++++++
 drivers/misc/cxl/cxl.h  |  6 ++++++
 drivers/misc/cxl/main.c |  2 ++
 drivers/misc/cxl/vphb.c | 37 +++++++++++++++++++++++--------------
 include/misc/cxl-base.h |  6 ++++++
 5 files changed, 72 insertions(+), 14 deletions(-)

Comments

Andrew Donnellan July 13, 2016, 5:52 a.m. UTC | #1 
On 11/07/16 21:50, Ian Munsie wrote:
> From: Ian Munsie <imunsie@au1.ibm.com>
>
> The cxl kernel API has a concept of a default context associated with
> each PCI device under the virtual PHB. The Mellanox CX4 will also use
> the cxl kernel API, but it does not use a virtual PHB - rather, the AFU
> appears as a physical function as a peer to the networking functions.
>
> In order to allow the kernel API to work with those networking
> functions, we will need to associate a default context with them as
> well. To this end, refactor the corresponding code to do this in vphb.c
> and export it so that it can be called from the PHB code.
>
> Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
> Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>

Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>

> diff --git a/drivers/misc/cxl/vphb.c b/drivers/misc/cxl/vphb.c
> index 012b6aa..c5b9c201 100644
> --- a/drivers/misc/cxl/vphb.c
> +++ b/drivers/misc/cxl/vphb.c
> @@ -40,11 +40,28 @@ static void cxl_teardown_msi_irqs(struct pci_dev *pdev)
>  	 */
>  }
>
> +bool _cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu)

If we're sharing these functions between the vPHB and peer models, do we 
have a better place than vphb.c for them?

> +{
> +	struct cxl_context *ctx;
> +
> +	/*
> +	 * Allocate a context to do cxl things too. This is used for interrupts

s/too/to/?
Ian Munsie July 13, 2016, 9:05 p.m. UTC | #2 
Excerpts from andrew.donnellan's message of 2016-07-13 15:52:45 +1000:
> > +bool _cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu)
> 
> If we're sharing these functions between the vPHB and peer models, do we 
> have a better place than vphb.c for them?

Sure, I might split them out into a new phb.c for V3. It just seemed a
little pointless to create a new file for two functions at the time, but
you are right that they don't really belong in vphb.c. I guess an
alternative would be to rename vphb.c to phb.c, but 90% of that file is
vphb specific... I'll split these out.

> > +{
> > +    struct cxl_context *ctx;
> > +
> > +    /*
> > +     * Allocate a context to do cxl things too. This is used for interrupts
> 
> s/too/to/?

Heh, the one part of the comment that I didn't change from Mikey's code ;-P

Will fix.

Cheers,
-Ian
diff mbox

Patch

diff --git a/drivers/misc/cxl/base.c b/drivers/misc/cxl/base.c
index d7dcf5b..1c3e737f 100644
--- a/drivers/misc/cxl/base.c
+++ b/drivers/misc/cxl/base.c
@@ -106,6 +106,41 @@  int cxl_update_properties(struct device_node *dn,
 }
 EXPORT_SYMBOL_GPL(cxl_update_properties);
 
+/*
+ * API calls into the driver that may be called from the PHB code and must be
+ * built in.
+ */
+bool cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu)
+{
+	bool ret;
+	struct cxl_calls *calls;
+
+	calls = cxl_calls_get();
+	if (!calls)
+		return false;
+
+	ret = calls->cxl_pci_associate_default_context(dev, afu);
+
+	cxl_calls_put(calls);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cxl_pci_associate_default_context);
+
+void cxl_pci_disable_device(struct pci_dev *dev)
+{
+	struct cxl_calls *calls;
+
+	calls = cxl_calls_get();
+	if (!calls)
+		return;
+
+	calls->cxl_pci_disable_device(dev);
+
+	cxl_calls_put(calls);
+}
+EXPORT_SYMBOL_GPL(cxl_pci_disable_device);
+
 static int __init cxl_base_init(void)
 {
 	struct device_node *np = NULL;
diff --git a/drivers/misc/cxl/cxl.h b/drivers/misc/cxl/cxl.h
index d4aae6f..b81f476 100644
--- a/drivers/misc/cxl/cxl.h
+++ b/drivers/misc/cxl/cxl.h
@@ -719,9 +719,15 @@  static inline u64 cxl_p2n_read(struct cxl_afu *afu, cxl_p2n_reg_t reg)
 ssize_t cxl_pci_afu_read_err_buffer(struct cxl_afu *afu, char *buf,
 				loff_t off, size_t count);
 
+/* Internal functions wrapped in cxl_base to allow PHB to call them */
+bool _cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu);
+void _cxl_pci_disable_device(struct pci_dev *dev);
 
 struct cxl_calls {
 	void (*cxl_slbia)(struct mm_struct *mm);
+	bool (*cxl_pci_associate_default_context)(struct pci_dev *dev, struct cxl_afu *afu);
+	void (*cxl_pci_disable_device)(struct pci_dev *dev);
+
 	struct module *owner;
 };
 int register_cxl_calls(struct cxl_calls *calls);
diff --git a/drivers/misc/cxl/main.c b/drivers/misc/cxl/main.c
index ae68c32..4e5474b 100644
--- a/drivers/misc/cxl/main.c
+++ b/drivers/misc/cxl/main.c
@@ -110,6 +110,8 @@  static inline void cxl_slbia_core(struct mm_struct *mm)
 
 static struct cxl_calls cxl_calls = {
 	.cxl_slbia = cxl_slbia_core,
+	.cxl_pci_associate_default_context = _cxl_pci_associate_default_context,
+	.cxl_pci_disable_device = _cxl_pci_disable_device,
 	.owner = THIS_MODULE,
 };
 
diff --git a/drivers/misc/cxl/vphb.c b/drivers/misc/cxl/vphb.c
index 012b6aa..c5b9c201 100644
--- a/drivers/misc/cxl/vphb.c
+++ b/drivers/misc/cxl/vphb.c
@@ -40,11 +40,28 @@  static void cxl_teardown_msi_irqs(struct pci_dev *pdev)
 	 */
 }
 
+bool _cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu)
+{
+	struct cxl_context *ctx;
+
+	/*
+	 * Allocate a context to do cxl things too. This is used for interrupts
+	 * in the peer model using a real phb, and if we eventually do DMA ops
+	 * in the virtual phb, we'll need a default context to attach them to.
+	 */
+	ctx = cxl_dev_context_init(dev);
+	if (!ctx)
+		return false;
+	dev->dev.archdata.cxl_ctx = ctx;
+
+	return (cxl_ops->afu_check_and_enable(afu) == 0);
+}
+/* exported via cxl_base */
+
 static bool cxl_pci_enable_device_hook(struct pci_dev *dev)
 {
 	struct pci_controller *phb;
 	struct cxl_afu *afu;
-	struct cxl_context *ctx;
 
 	phb = pci_bus_to_host(dev->bus);
 	afu = (struct cxl_afu *)phb->private_data;
@@ -57,19 +74,10 @@  static bool cxl_pci_enable_device_hook(struct pci_dev *dev)
 	set_dma_ops(&dev->dev, &dma_direct_ops);
 	set_dma_offset(&dev->dev, PAGE_OFFSET);
 
-	/*
-	 * Allocate a context to do cxl things too.  If we eventually do real
-	 * DMA ops, we'll need a default context to attach them to
-	 */
-	ctx = cxl_dev_context_init(dev);
-	if (!ctx)
-		return false;
-	dev->dev.archdata.cxl_ctx = ctx;
-
-	return (cxl_ops->afu_check_and_enable(afu) == 0);
+	return _cxl_pci_associate_default_context(dev, afu);
 }
 
-static void cxl_pci_disable_device(struct pci_dev *dev)
+void _cxl_pci_disable_device(struct pci_dev *dev)
 {
 	struct cxl_context *ctx = cxl_get_context(dev);
 
@@ -82,6 +90,7 @@  static void cxl_pci_disable_device(struct pci_dev *dev)
 		cxl_release_context(ctx);
 	}
 }
+/* exported via cxl_base */
 
 static resource_size_t cxl_pci_window_alignment(struct pci_bus *bus,
 						unsigned long type)
@@ -197,8 +206,8 @@  static struct pci_controller_ops cxl_pci_controller_ops =
 {
 	.probe_mode = cxl_pci_probe_mode,
 	.enable_device_hook = cxl_pci_enable_device_hook,
-	.disable_device = cxl_pci_disable_device,
-	.release_device = cxl_pci_disable_device,
+	.disable_device = _cxl_pci_disable_device,
+	.release_device = _cxl_pci_disable_device,
 	.window_alignment = cxl_pci_window_alignment,
 	.reset_secondary_bus = cxl_pci_reset_secondary_bus,
 	.setup_msi_irqs = cxl_setup_msi_irqs,
diff --git a/include/misc/cxl-base.h b/include/misc/cxl-base.h
index f53808f..bb7e629 100644
--- a/include/misc/cxl-base.h
+++ b/include/misc/cxl-base.h
@@ -10,6 +10,8 @@ 
 #ifndef _MISC_CXL_BASE_H
 #define _MISC_CXL_BASE_H
 
+#include <misc/cxl.h>
+
 #ifdef CONFIG_CXL_BASE
 
 #define CXL_IRQ_RANGES 4
@@ -39,6 +41,8 @@  static inline void cxl_ctx_put(void)
 struct cxl_afu *cxl_afu_get(struct cxl_afu *afu);
 void cxl_afu_put(struct cxl_afu *afu);
 void cxl_slbia(struct mm_struct *mm);
+bool cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu);
+void cxl_pci_disable_device(struct pci_dev *dev);
 
 #else /* CONFIG_CXL_BASE */
 
@@ -46,6 +50,8 @@  static inline bool cxl_ctx_in_use(void) { return false; }
 static inline struct cxl_afu *cxl_afu_get(struct cxl_afu *afu) { return NULL; }
 static inline void cxl_afu_put(struct cxl_afu *afu) {}
 static inline void cxl_slbia(struct mm_struct *mm) {}
+static inline bool cxl_pci_associate_default_context(struct pci_dev *dev, struct cxl_afu *afu) { return false; }
+static inline void cxl_pci_disable_device(struct pci_dev *dev) {}
 
 #endif /* CONFIG_CXL_BASE */