| Message ID | 20220610202259.3544623-8-ira.weiny@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | CXL: Read CDAT and DSMAS data | expand |
On Fri, Jun 10, 2022 at 01:22:58PM -0700, Ira Weiny wrote: > From: Ira Weiny <ira.weiny@intel.com> > > The CDAT read may fail for a number of reasons but mainly it is possible > to get different parts of a valid state. The checksum in the CDAT table > protects against this. > > Now that the cdat data is validated, issue a retry if the CDAT read > fails. For now 5 retries are implemented. > > Reviewed-by: Ben Widawsky <bwidawsk@kernel.org> > Signed-off-by: Ira Weiny <ira.weiny@intel.com> > Reviewed-by: Alison Schofield <alison.schofield@intel.com> > --- > Changes from V10 > Pick up review tag and fix commit message > > Changes from V9 > Alison Schofield/Davidlohr Bueso > Print debug on each iteration and error only after failure > > Changes from V8 > Move code to cxl/core/pci.c > > Changes from V6 > Move to pci.c > Fix retries count > Change to 5 retries > > Changes from V5: > New patch -- easy to push off or drop. > --- > drivers/cxl/core/pci.c | 40 +++++++++++++++++++++++++++++++--------- > 1 file changed, 31 insertions(+), 9 deletions(-) > > diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c > index cb70287e2984..fd02bc7c0d97 100644 > --- a/drivers/cxl/core/pci.c > +++ b/drivers/cxl/core/pci.c > @@ -617,19 +617,13 @@ static int cxl_cdat_read_table(struct device *dev, > return rc; > } > > -/** > - * read_cdat_data - Read the CDAT data on this port > - * @port: Port to read data from > - * > - * This call will sleep waiting for responses from the DOE mailbox. > - */ > -void read_cdat_data(struct cxl_port *port) > +static int __read_cdat_data(struct cxl_port *port) > { > static struct pci_doe_mb *cdat_mb; > struct device *dev = &port->dev; > struct device *uport = port->uport; > size_t cdat_length; > - int ret; > + int ret = 0; > > /* > * Ensure a reference on the underlying uport device which has the > @@ -640,17 +634,21 @@ void read_cdat_data(struct cxl_port *port) > cdat_mb = find_cdat_mb(uport); > if (!cdat_mb) { > dev_dbg(dev, "No CDAT mailbox\n"); > + ret = -EIO; > goto out; > } > > if (cxl_cdat_get_length(dev, cdat_mb, &cdat_length)) { > dev_dbg(dev, "No CDAT length\n"); > + ret = -EIO; > goto out; > } > > port->cdat.table = devm_kzalloc(dev, cdat_length, GFP_KERNEL); > - if (!port->cdat.table) > + if (!port->cdat.table) { > + ret = -ENOMEM; > goto out; > + } > > port->cdat.length = cdat_length; > ret = cxl_cdat_read_table(dev, cdat_mb, &port->cdat); > @@ -664,5 +662,29 @@ void read_cdat_data(struct cxl_port *port) > > out: > put_device(uport); > + return ret; > +} > + > +/** > + * read_cdat_data - Read the CDAT data on this port > + * @port: Port to read data from > + * > + * This call will sleep waiting for responses from the DOE mailbox. > + */ > +void read_cdat_data(struct cxl_port *port) > +{ > + int retries = 5; > + int rc; > + > + while (retries--) { > + rc = __read_cdat_data(port); > + if (!rc) > + return; > + dev_dbg(&port->dev, > + "CDAT data read error rc=%d (retries %d)\n", > + rc, retries); > + } > + dev_err(&port->dev, "CDAT data read failed after %d retries\n", > + retries); > } > EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL); > -- > 2.35.1 >
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index cb70287e2984..fd02bc7c0d97 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -617,19 +617,13 @@ static int cxl_cdat_read_table(struct device *dev, return rc; } -/** - * read_cdat_data - Read the CDAT data on this port - * @port: Port to read data from - * - * This call will sleep waiting for responses from the DOE mailbox. - */ -void read_cdat_data(struct cxl_port *port) +static int __read_cdat_data(struct cxl_port *port) { static struct pci_doe_mb *cdat_mb; struct device *dev = &port->dev; struct device *uport = port->uport; size_t cdat_length; - int ret; + int ret = 0; /* * Ensure a reference on the underlying uport device which has the @@ -640,17 +634,21 @@ void read_cdat_data(struct cxl_port *port) cdat_mb = find_cdat_mb(uport); if (!cdat_mb) { dev_dbg(dev, "No CDAT mailbox\n"); + ret = -EIO; goto out; } if (cxl_cdat_get_length(dev, cdat_mb, &cdat_length)) { dev_dbg(dev, "No CDAT length\n"); + ret = -EIO; goto out; } port->cdat.table = devm_kzalloc(dev, cdat_length, GFP_KERNEL); - if (!port->cdat.table) + if (!port->cdat.table) { + ret = -ENOMEM; goto out; + } port->cdat.length = cdat_length; ret = cxl_cdat_read_table(dev, cdat_mb, &port->cdat); @@ -664,5 +662,29 @@ void read_cdat_data(struct cxl_port *port) out: put_device(uport); + return ret; +} + +/** + * read_cdat_data - Read the CDAT data on this port + * @port: Port to read data from + * + * This call will sleep waiting for responses from the DOE mailbox. + */ +void read_cdat_data(struct cxl_port *port) +{ + int retries = 5; + int rc; + + while (retries--) { + rc = __read_cdat_data(port); + if (!rc) + return; + dev_dbg(&port->dev, + "CDAT data read error rc=%d (retries %d)\n", + rc, retries); + } + dev_err(&port->dev, "CDAT data read failed after %d retries\n", + retries); } EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL);