diff options
Diffstat (limited to 'drivers/cxl/core/bus.c')
| -rw-r--r-- | drivers/cxl/core/bus.c | 80 |
1 files changed, 69 insertions, 11 deletions
diff --git a/drivers/cxl/core/bus.c b/drivers/cxl/core/bus.c index 9a8fa88b634c..6dfdeaf999f0 100644 --- a/drivers/cxl/core/bus.c +++ b/drivers/cxl/core/bus.c @@ -453,11 +453,38 @@ err: } EXPORT_SYMBOL_GPL(cxl_add_dport); +static int decoder_populate_targets(struct device *host, + struct cxl_decoder *cxld, + struct cxl_port *port, int *target_map, + int nr_targets) +{ + int rc = 0, i; + + if (!target_map) + return 0; + + device_lock(&port->dev); + for (i = 0; i < nr_targets; i++) { + struct cxl_dport *dport = find_dport(port, target_map[i]); + + if (!dport) { + rc = -ENXIO; + break; + } + dev_dbg(host, "%s: target: %d\n", dev_name(dport->dport), i); + cxld->target[i] = dport; + } + device_unlock(&port->dev); + + return rc; +} + static struct cxl_decoder * -cxl_decoder_alloc(struct cxl_port *port, int nr_targets, resource_size_t base, - resource_size_t len, int interleave_ways, - int interleave_granularity, enum cxl_decoder_type type, - unsigned long flags) +cxl_decoder_alloc(struct device *host, struct cxl_port *port, int nr_targets, + resource_size_t base, resource_size_t len, + int interleave_ways, int interleave_granularity, + enum cxl_decoder_type type, unsigned long flags, + int *target_map) { struct cxl_decoder *cxld; struct device *dev; @@ -493,10 +520,10 @@ cxl_decoder_alloc(struct cxl_port *port, int nr_targets, resource_size_t base, .target_type = type, }; - /* handle implied target_list */ - if (interleave_ways == 1) - cxld->target[0] = - list_first_entry(&port->dports, struct cxl_dport, list); + rc = decoder_populate_targets(host, cxld, port, target_map, nr_targets); + if (rc) + goto err; + dev = &cxld->dev; device_initialize(dev); device_set_pm_not_required(dev); @@ -519,14 +546,19 @@ struct cxl_decoder * devm_cxl_add_decoder(struct device *host, struct cxl_port *port, int nr_targets, resource_size_t base, resource_size_t len, int interleave_ways, int interleave_granularity, - enum cxl_decoder_type type, unsigned long flags) + enum cxl_decoder_type type, unsigned long flags, + int *target_map) { struct cxl_decoder *cxld; struct device *dev; int rc; - cxld = cxl_decoder_alloc(port, nr_targets, base, len, interleave_ways, - interleave_granularity, type, flags); + if (nr_targets > CXL_DECODER_MAX_INTERLEAVE) + return ERR_PTR(-EINVAL); + + cxld = cxl_decoder_alloc(host, port, nr_targets, base, len, + interleave_ways, interleave_granularity, type, + flags, target_map); if (IS_ERR(cxld)) return cxld; @@ -550,6 +582,32 @@ err: } EXPORT_SYMBOL_GPL(devm_cxl_add_decoder); +/* + * Per the CXL specification (8.2.5.12 CXL HDM Decoder Capability Structure) + * single ported host-bridges need not publish a decoder capability when a + * passthrough decode can be assumed, i.e. all transactions that the uport sees + * are claimed and passed to the single dport. Default the range a 0-base + * 0-length until the first CXL region is activated. + */ +struct cxl_decoder *devm_cxl_add_passthrough_decoder(struct device *host, + struct cxl_port *port) +{ + struct cxl_dport *dport; + int target_map[1]; + + device_lock(&port->dev); + dport = list_first_entry_or_null(&port->dports, typeof(*dport), list); + device_unlock(&port->dev); + + if (!dport) + return ERR_PTR(-ENXIO); + + target_map[0] = dport->port_id; + return devm_cxl_add_decoder(host, port, 1, 0, 0, 1, PAGE_SIZE, + CXL_DECODER_EXPANDER, 0, target_map); +} +EXPORT_SYMBOL_GPL(devm_cxl_add_passthrough_decoder); + /** * __cxl_driver_register - register a driver for the cxl bus * @cxl_drv: cxl driver structure to attach |