From: Ira Weiny <[email protected]>
Memory devices need the CDAT data from the device. This data is read
from a DOE mailbox which supports the CDAT protocol.
Search the DOE auxiliary devices for the one which supports the CDAT
protocol. Cache that device to be used for future queries.
Signed-off-by: Ira Weiny <[email protected]>
---
drivers/cxl/cxl.h | 3 +++
drivers/cxl/cxlmem.h | 2 ++
drivers/cxl/pci.c | 43 ++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 47 insertions(+), 1 deletion(-)
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 962629c5775f..7169101db553 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -90,6 +90,9 @@ static inline int cxl_hdm_decoder_count(u32 cap_hdr)
#define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
#define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
+#define CXL_DOE_PROTOCOL_COMPLIANCE 0
+#define CXL_DOE_PROTOCOL_TABLE_ACCESS 2
+
/*
* Using struct_group() allows for per register-block-type helper routines,
* without requiring block-type agnostic code to include the prefix.
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 5d33ce24fe09..0fefe43951e3 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -117,6 +117,7 @@ struct cxl_endpoint_dvsec_info {
* Currently only memory devices are represented.
*
* @dev: The device associated with this CXL state
+ * @cdat_doe: Auxiliary DOE device capabile of reading CDAT
* @regs: Parsed register blocks
* @cxl_dvsec: Offset to the PCIe device DVSEC
* @payload_size: Size of space for payload
@@ -149,6 +150,7 @@ struct cxl_endpoint_dvsec_info {
struct cxl_dev_state {
struct device *dev;
+ struct pci_doe_dev *cdat_doe;
struct cxl_regs regs;
int cxl_dvsec;
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index d4ae79b62a14..dcc55c4efd85 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -536,12 +536,53 @@ static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds)
return rc;
}
+static int cxl_match_cdat_doe_device(struct device *dev, const void *data)
+{
+ const struct cxl_dev_state *cxlds = data;
+ struct auxiliary_device *adev;
+ struct pci_doe_dev *doe_dev;
+
+ /* First determine if this auxiliary device belongs to the cxlds */
+ if (cxlds->dev != dev->parent)
+ return 0;
+
+ adev = to_auxiliary_dev(dev);
+ doe_dev = container_of(adev, struct pci_doe_dev, adev);
+
+ /* If it is one of ours check for the CDAT protocol */
+ if (pci_doe_supports_prot(doe_dev, PCI_DVSEC_VENDOR_ID_CXL,
+ CXL_DOE_PROTOCOL_TABLE_ACCESS))
+ return 1;
+
+ return 0;
+}
+
static int cxl_setup_doe_devices(struct cxl_dev_state *cxlds)
{
struct device *dev = cxlds->dev;
struct pci_dev *pdev = to_pci_dev(dev);
+ struct auxiliary_device *adev;
+ int rc;
- return pci_doe_create_doe_devices(pdev);
+ rc = pci_doe_create_doe_devices(pdev);
+ if (rc)
+ return rc;
+
+ adev = auxiliary_find_device(NULL, cxlds, &cxl_match_cdat_doe_device);
+
+ if (adev) {
+ struct pci_doe_dev *doe_dev = container_of(adev,
+ struct pci_doe_dev,
+ adev);
+
+ /*
+ * No reference need be taken. The DOE device lifetime is
+ * longer that the CXL device state lifetime
+ */
+ cxlds->cdat_doe = doe_dev;
+ }
+
+ return 0;
}
static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
--
2.31.1
On 22-01-31 23:19:48, [email protected] wrote:
> From: Ira Weiny <[email protected]>
>
> Memory devices need the CDAT data from the device. This data is read
> from a DOE mailbox which supports the CDAT protocol.
>
> Search the DOE auxiliary devices for the one which supports the CDAT
> protocol. Cache that device to be used for future queries.
>
> Signed-off-by: Ira Weiny <[email protected]>
> ---
> drivers/cxl/cxl.h | 3 +++
> drivers/cxl/cxlmem.h | 2 ++
> drivers/cxl/pci.c | 43 ++++++++++++++++++++++++++++++++++++++++++-
> 3 files changed, 47 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index 962629c5775f..7169101db553 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -90,6 +90,9 @@ static inline int cxl_hdm_decoder_count(u32 cap_hdr)
> #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
> #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
>
> +#define CXL_DOE_PROTOCOL_COMPLIANCE 0
> +#define CXL_DOE_PROTOCOL_TABLE_ACCESS 2
> +
> /*
> * Using struct_group() allows for per register-block-type helper routines,
> * without requiring block-type agnostic code to include the prefix.
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index 5d33ce24fe09..0fefe43951e3 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -117,6 +117,7 @@ struct cxl_endpoint_dvsec_info {
> * Currently only memory devices are represented.
> *
> * @dev: The device associated with this CXL state
> + * @cdat_doe: Auxiliary DOE device capabile of reading CDAT
> * @regs: Parsed register blocks
> * @cxl_dvsec: Offset to the PCIe device DVSEC
> * @payload_size: Size of space for payload
> @@ -149,6 +150,7 @@ struct cxl_endpoint_dvsec_info {
> struct cxl_dev_state {
> struct device *dev;
>
> + struct pci_doe_dev *cdat_doe;
> struct cxl_regs regs;
> int cxl_dvsec;
>
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index d4ae79b62a14..dcc55c4efd85 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -536,12 +536,53 @@ static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds)
> return rc;
> }
>
> +static int cxl_match_cdat_doe_device(struct device *dev, const void *data)
> +{
> + const struct cxl_dev_state *cxlds = data;
> + struct auxiliary_device *adev;
> + struct pci_doe_dev *doe_dev;
> +
> + /* First determine if this auxiliary device belongs to the cxlds */
> + if (cxlds->dev != dev->parent)
> + return 0;
I don't understand auxiliary bus but I'm wondering why it's checking the parent
of the device?
> +
> + adev = to_auxiliary_dev(dev);
> + doe_dev = container_of(adev, struct pci_doe_dev, adev);
> +
> + /* If it is one of ours check for the CDAT protocol */
> + if (pci_doe_supports_prot(doe_dev, PCI_DVSEC_VENDOR_ID_CXL,
> + CXL_DOE_PROTOCOL_TABLE_ACCESS))
> + return 1;
> +
> + return 0;
> +}
> +
> static int cxl_setup_doe_devices(struct cxl_dev_state *cxlds)
> {
> struct device *dev = cxlds->dev;
> struct pci_dev *pdev = to_pci_dev(dev);
> + struct auxiliary_device *adev;
> + int rc;
>
> - return pci_doe_create_doe_devices(pdev);
> + rc = pci_doe_create_doe_devices(pdev);
> + if (rc)
> + return rc;
> +
> + adev = auxiliary_find_device(NULL, cxlds, &cxl_match_cdat_doe_device);
> +
> + if (adev) {
> + struct pci_doe_dev *doe_dev = container_of(adev,
> + struct pci_doe_dev,
> + adev);
> +
> + /*
> + * No reference need be taken. The DOE device lifetime is
> + * longer that the CXL device state lifetime
> + */
You're holding a reference to the adev here. Did you mean to drop it?
> + cxlds->cdat_doe = doe_dev;
> + }
> +
> + return 0;
> }
>
> static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> --
> 2.31.1
>
On Tue, Feb 01, 2022 at 10:49:47AM -0800, Widawsky, Ben wrote:
> On 22-01-31 23:19:48, [email protected] wrote:
> > From: Ira Weiny <[email protected]>
> >
> > Memory devices need the CDAT data from the device. This data is read
> > from a DOE mailbox which supports the CDAT protocol.
> >
> > Search the DOE auxiliary devices for the one which supports the CDAT
> > protocol. Cache that device to be used for future queries.
> >
> > Signed-off-by: Ira Weiny <[email protected]>
[snip]
> >
> > diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> > index d4ae79b62a14..dcc55c4efd85 100644
> > --- a/drivers/cxl/pci.c
> > +++ b/drivers/cxl/pci.c
> > @@ -536,12 +536,53 @@ static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds)
> > return rc;
> > }
> >
> > +static int cxl_match_cdat_doe_device(struct device *dev, const void *data)
> > +{
> > + const struct cxl_dev_state *cxlds = data;
> > + struct auxiliary_device *adev;
> > + struct pci_doe_dev *doe_dev;
> > +
> > + /* First determine if this auxiliary device belongs to the cxlds */
> > + if (cxlds->dev != dev->parent)
> > + return 0;
>
> I don't understand auxiliary bus but I'm wondering why it's checking the parent
> of the device?
auxiliary_find_device() iterates all the auxiliary devices in the system. This
check was a way for the match function to know if the auxiliary device belongs
to the cxlds we are interested in...
But now that I think about it we could have other auxiliary devices attached
which are not DOE... :-/ So this check is not complete.
FWIW I'm not thrilled with the way auxiliary_find_device() is defined. And now
that I look at it I think the only user of it currently is wrong. They too
have a check like this but it is after another check... :-/
I was hoping to avoid having a list of DOE devices in the cxlds and simply let
the auxiliary bus infrastructure do that somehow. IIRC Jonathan was thinking
along the same lines. I think he actually suggested auxiliary_find_device()...
It would be nice if I could have an aux_find_child() or something which
iterated the auxiliary devices attached to a particular parent device. I've
just not figured out exactly how to implement that better than what I did here.
>
> > +
> > + adev = to_auxiliary_dev(dev);
> > + doe_dev = container_of(adev, struct pci_doe_dev, adev);
> > +
> > + /* If it is one of ours check for the CDAT protocol */
> > + if (pci_doe_supports_prot(doe_dev, PCI_DVSEC_VENDOR_ID_CXL,
> > + CXL_DOE_PROTOCOL_TABLE_ACCESS))
> > + return 1;
> > +
> > + return 0;
> > +}
> > +
> > static int cxl_setup_doe_devices(struct cxl_dev_state *cxlds)
> > {
> > struct device *dev = cxlds->dev;
> > struct pci_dev *pdev = to_pci_dev(dev);
> > + struct auxiliary_device *adev;
> > + int rc;
> >
> > - return pci_doe_create_doe_devices(pdev);
> > + rc = pci_doe_create_doe_devices(pdev);
> > + if (rc)
> > + return rc;
> > +
> > + adev = auxiliary_find_device(NULL, cxlds, &cxl_match_cdat_doe_device);
> > +
> > + if (adev) {
> > + struct pci_doe_dev *doe_dev = container_of(adev,
> > + struct pci_doe_dev,
> > + adev);
> > +
> > + /*
> > + * No reference need be taken. The DOE device lifetime is
> > + * longer that the CXL device state lifetime
> > + */
>
> You're holding a reference to the adev here. Did you mean to drop it?
Does find device get a reference? ... Ah shoot I did not see that.
Yea the reference should be dropped somewhere.
Thanks,
Ira
>
> > + cxlds->cdat_doe = doe_dev;
> > + }
> > +
> > + return 0;
> > }
> >
> > static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> > --
> > 2.31.1
> >
On Tue, 1 Feb 2022 14:18:41 -0800
Ira Weiny <[email protected]> wrote:
> On Tue, Feb 01, 2022 at 10:49:47AM -0800, Widawsky, Ben wrote:
> > On 22-01-31 23:19:48, [email protected] wrote:
> > > From: Ira Weiny <[email protected]>
> > >
> > > Memory devices need the CDAT data from the device. This data is read
> > > from a DOE mailbox which supports the CDAT protocol.
> > >
> > > Search the DOE auxiliary devices for the one which supports the CDAT
> > > protocol. Cache that device to be used for future queries.
> > >
> > > Signed-off-by: Ira Weiny <[email protected]>
>
> [snip]
>
> > >
> > > diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> > > index d4ae79b62a14..dcc55c4efd85 100644
> > > --- a/drivers/cxl/pci.c
> > > +++ b/drivers/cxl/pci.c
> > > @@ -536,12 +536,53 @@ static int cxl_dvsec_ranges(struct cxl_dev_state *cxlds)
> > > return rc;
> > > }
> > >
> > > +static int cxl_match_cdat_doe_device(struct device *dev, const void *data)
> > > +{
> > > + const struct cxl_dev_state *cxlds = data;
> > > + struct auxiliary_device *adev;
> > > + struct pci_doe_dev *doe_dev;
> > > +
> > > + /* First determine if this auxiliary device belongs to the cxlds */
> > > + if (cxlds->dev != dev->parent)
> > > + return 0;
> >
> > I don't understand auxiliary bus but I'm wondering why it's checking the parent
> > of the device?
>
> auxiliary_find_device() iterates all the auxiliary devices in the system. This
> check was a way for the match function to know if the auxiliary device belongs
> to the cxlds we are interested in...
>
> But now that I think about it we could have other auxiliary devices attached
> which are not DOE... :-/ So this check is not complete.
>
> FWIW I'm not thrilled with the way auxiliary_find_device() is defined. And now
> that I look at it I think the only user of it currently is wrong. They too
> have a check like this but it is after another check... :-/
>
> I was hoping to avoid having a list of DOE devices in the cxlds and simply let
> the auxiliary bus infrastructure do that somehow. IIRC Jonathan was thinking
> along the same lines. I think he actually suggested auxiliary_find_device()...
Ah.. I think I'd been thinking it was scoped to a single parent rather than
all devices in the system. Definitely rather horrible.
Can we do something with device_for_each_child() instead with a match on
bus type to check its an auxilliary bus device then I guess a name based
check on whether that is a doe. etc.
>
> It would be nice if I could have an aux_find_child() or something which
> iterated the auxiliary devices attached to a particular parent device. I've
> just not figured out exactly how to implement that better than what I did here.
>
> >
> > > +
> > > + adev = to_auxiliary_dev(dev);
> > > + doe_dev = container_of(adev, struct pci_doe_dev, adev);
> > > +
> > > + /* If it is one of ours check for the CDAT protocol */
> > > + if (pci_doe_supports_prot(doe_dev, PCI_DVSEC_VENDOR_ID_CXL,
> > > + CXL_DOE_PROTOCOL_TABLE_ACCESS))
> > > + return 1;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > static int cxl_setup_doe_devices(struct cxl_dev_state *cxlds)
> > > {
> > > struct device *dev = cxlds->dev;
> > > struct pci_dev *pdev = to_pci_dev(dev);
> > > + struct auxiliary_device *adev;
> > > + int rc;
> > >
> > > - return pci_doe_create_doe_devices(pdev);
> > > + rc = pci_doe_create_doe_devices(pdev);
> > > + if (rc)
> > > + return rc;
> > > +
> > > + adev = auxiliary_find_device(NULL, cxlds, &cxl_match_cdat_doe_device);
> > > +
> > > + if (adev) {
> > > + struct pci_doe_dev *doe_dev = container_of(adev,
> > > + struct pci_doe_dev,
> > > + adev);
> > > +
> > > + /*
> > > + * No reference need be taken. The DOE device lifetime is
> > > + * longer that the CXL device state lifetime
> > > + */
> >
> > You're holding a reference to the adev here. Did you mean to drop it?
>
> Does find device get a reference? ... Ah shoot I did not see that.
>
> Yea the reference should be dropped somewhere.
>
> Thanks,
> Ira
>
> >
> > > + cxlds->cdat_doe = doe_dev;
> > > + }
> > > +
> > > + return 0;
> > > }
> > >
> > > static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> > > --
> > > 2.31.1
> > >