On 22-06-04 17:50:45, ira.weiny@xxxxxxxxx wrote: > From: Ira Weiny <ira.weiny@xxxxxxxxx> > > Each CXL device may have multiple DOE mailbox capabilities and each > mailbox may support multiple protocols. CXL port devices need to query > the CDAT information specifically. > > Search the DOE mailboxes for one which supports the CDAT protocol. > Cache that mailbox to be used for future queries. > > Only support memory devices at this time. > > Cc: Ben Widawsky <ben.widawsky@xxxxxxxxx> > Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx> > > --- > Changes from V9 > Ben Widawsky > s/cxl_find_cdat_mb/cxl_cache_cdat_mb/; add kdoc > Jonathan Cameron > Move cache_cdat to port probe [Not 100% necessary but it > goes along with reading the cdat data.] > > Changes from V8 > Incorporate feedback from Jonathan > Move all this to the cxl_port object > > Changes from V7 > Minor code clean ups > > Changes from V6 > Adjust for aux devices being a CXL only concept > Update commit msg. > Ensure devices iterated by auxiliary_find_device() are checked > to be DOE devices prior to checking for the CDAT > protocol > From Ben > Ensure reference from auxiliary_find_device() is dropped > --- > drivers/cxl/core/pci.c | 35 +++++++++++++++++++++++++++++++++++ > drivers/cxl/cxl.h | 2 ++ > drivers/cxl/cxlpci.h | 1 + > drivers/cxl/port.c | 2 ++ > 4 files changed, 40 insertions(+) > > diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c > index c4c99ff7b55e..d814d8317975 100644 > --- a/drivers/cxl/core/pci.c > +++ b/drivers/cxl/core/pci.c > @@ -4,11 +4,14 @@ > #include <linux/device.h> > #include <linux/delay.h> > #include <linux/pci.h> > +#include <linux/pci-doe.h> > #include <cxlpci.h> > #include <cxlmem.h> > #include <cxl.h> > #include "core.h" > > +#define CXL_DOE_PROTOCOL_TABLE_ACCESS 2 > + > /** > * DOC: cxl core pci > * > @@ -458,3 +461,35 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm) > return 0; > } > EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, CXL); > + > +/** > + * cxl_cache_cdat_mb() -- cache the DOE mailbox which suports the CDAT protocol > + * > + * @port: Port to containing DOE Mailboxes > + * > + * Cache a pointer to the doe mailbox which supports CDAT. > + */ > +void cxl_cache_cdat_mb(struct cxl_port *port) > +{ > + struct device *dev = port->uport; > + struct cxl_memdev *cxlmd; > + struct cxl_dev_state *cxlds; > + int i; > + > + if (!is_cxl_memdev(dev)) > + return; > + > + cxlmd = to_cxl_memdev(dev); > + cxlds = cxlmd->cxlds; > + > + for (i = 0; i < cxlds->num_mbs; i++) { > + struct pci_doe_mb *cur = cxlds->doe_mbs[i]; > + > + if (pci_doe_supports_prot(cur, PCI_DVSEC_VENDOR_ID_CXL, > + CXL_DOE_PROTOCOL_TABLE_ACCESS)) { > + port->cdat_mb = cur; What happens if cxl_pci is unloaded after this? Would it be better to copy out the CDAT info? Otherwise, I think you need to hold a ref on the PCI device (though I only took a quick look). > + return; > + } > + } > +} > +EXPORT_SYMBOL_NS_GPL(cxl_cache_cdat_mb, CXL); > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h > index 140dc3278cde..0a86be589ffc 100644 > --- a/drivers/cxl/cxl.h > +++ b/drivers/cxl/cxl.h > @@ -267,6 +267,7 @@ struct cxl_nvdimm { > * @component_reg_phys: component register capability base address (optional) > * @dead: last ep has been removed, force port re-creation > * @depth: How deep this port is relative to the root. depth 0 is the root. > + * @cdat_mb: Mailbox which supports the CDAT protocol > */ > struct cxl_port { > struct device dev; > @@ -278,6 +279,7 @@ struct cxl_port { > resource_size_t component_reg_phys; > bool dead; > unsigned int depth; > + struct pci_doe_mb *cdat_mb; > }; > > /** > diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h > index fce1c11729c2..ddbb8b77752e 100644 > --- a/drivers/cxl/cxlpci.h > +++ b/drivers/cxl/cxlpci.h > @@ -74,4 +74,5 @@ static inline resource_size_t cxl_regmap_to_base(struct pci_dev *pdev, > int devm_cxl_port_enumerate_dports(struct cxl_port *port); > struct cxl_dev_state; > int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm); > +void cxl_cache_cdat_mb(struct cxl_port *port); > #endif /* __CXL_PCI_H__ */ > diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c > index 3cf308f114c4..04f3d1fc6e07 100644 > --- a/drivers/cxl/port.c > +++ b/drivers/cxl/port.c > @@ -49,6 +49,8 @@ static int cxl_port_probe(struct device *dev) > if (IS_ERR(cxlhdm)) > return PTR_ERR(cxlhdm); > > + cxl_cache_cdat_mb(port); > + > if (is_cxl_endpoint(port)) { > struct cxl_memdev *cxlmd = to_cxl_memdev(port->uport); > struct cxl_dev_state *cxlds = cxlmd->cxlds; > -- > 2.35.1 >