On Tue, 24 Aug 2021 09:07:39 -0700 Dan Williams <[email protected]> wrote:
> As found by cxl_test, the implementation populated the target_list for > the single dport exceptional case, it missed populating the target_list > for the typical multi-dport case. Description makes this sound like a fix, rather than what I think it is which is implementing a new feature... > > Walk the hosting port's dport list and populate based on the passed in > map. > > Move devm_cxl_add_passthrough_decoder() out of line now that it does the > work of generating a target_map. > > Before: > $ cat /sys/bus/cxl/devices/root2/decoder*/target_list > 0 > > 0 > > > After: > $ cat /sys/bus/cxl/devices/root2/decoder*/target_list > 0 > 0,1,2,3 > 0 > 0,1,2,3 > > Where root2 is a CXL topology root object generated by 'cxl_test'. > > Acked-by: Ben Widawsky <[email protected]> > Signed-off-by: Dan Williams <[email protected]> one trivial inline. Otherwise looks fine to me. Reviewed-by: Jonathan Cameron <[email protected]> J > --- > drivers/cxl/acpi.c | 13 +++++++++- > drivers/cxl/core/bus.c | 65 > +++++++++++++++++++++++++++++++++++++++--------- > drivers/cxl/cxl.h | 25 +++++++----------- > 3 files changed, 75 insertions(+), 28 deletions(-) > > diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c > index 3fcb704c647f..6aea27c8fd4c 100644 > --- a/drivers/cxl/acpi.c > +++ b/drivers/cxl/acpi.c > @@ -52,6 +52,12 @@ static int cxl_acpi_cfmws_verify(struct device *dev, > return -EINVAL; > } > > + if (CFMWS_INTERLEAVE_WAYS(cfmws) > CXL_DECODER_MAX_INTERLEAVE) { > + dev_err(dev, "CFMWS Interleave Ways (%d) too large\n", > + CFMWS_INTERLEAVE_WAYS(cfmws)); > + return -EINVAL; > + } > + > expected_len = struct_size((cfmws), interleave_targets, > CFMWS_INTERLEAVE_WAYS(cfmws)); > > @@ -71,6 +77,7 @@ static int cxl_acpi_cfmws_verify(struct device *dev, > static void cxl_add_cfmws_decoders(struct device *dev, > struct cxl_port *root_port) > { > + int target_map[CXL_DECODER_MAX_INTERLEAVE]; > struct acpi_cedt_cfmws *cfmws; > struct cxl_decoder *cxld; > acpi_size len, cur = 0; > @@ -83,6 +90,7 @@ static void cxl_add_cfmws_decoders(struct device *dev, > > while (cur < len) { > struct acpi_cedt_header *c = cedt_subtable + cur; > + int i; > > if (c->type != ACPI_CEDT_TYPE_CFMWS) { > cur += c->length; > @@ -108,6 +116,9 @@ static void cxl_add_cfmws_decoders(struct device *dev, > continue; > } > > + for (i = 0; i < CFMWS_INTERLEAVE_WAYS(cfmws); i++) > + target_map[i] = cfmws->interleave_targets[i]; > + > flags = cfmws_to_decoder_flags(cfmws->restrictions); > cxld = devm_cxl_add_decoder(dev, root_port, > CFMWS_INTERLEAVE_WAYS(cfmws), > @@ -115,7 +126,7 @@ static void cxl_add_cfmws_decoders(struct device *dev, > CFMWS_INTERLEAVE_WAYS(cfmws), > CFMWS_INTERLEAVE_GRANULARITY(cfmws), > CXL_DECODER_EXPANDER, > - flags); > + flags, target_map); > > if (IS_ERR(cxld)) { > dev_err(dev, "Failed to add decoder for %#llx-%#llx\n", > diff --git a/drivers/cxl/core/bus.c b/drivers/cxl/core/bus.c > index 8073354ba232..9a755a37eadf 100644 > --- a/drivers/cxl/core/bus.c > +++ b/drivers/cxl/core/bus.c > @@ -454,14 +454,15 @@ int cxl_add_dport(struct cxl_port *port, struct device > *dport_dev, int port_id, > EXPORT_SYMBOL_GPL(cxl_add_dport); > > 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; > - int rc = 0; > + int rc = 0, i; > > if (interleave_ways < 1) > return ERR_PTR(-EINVAL); > @@ -493,10 +494,19 @@ 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); > + device_lock(&port->dev); > + for (i = 0; target_map && i < nr_targets; i++) { Perhaps move target map check much earlier rather than putting it int he loop condition? I don't think the loop is modifying it... > + struct cxl_dport *dport = find_dport(port, target_map[i]); > + > + if (!dport) { > + rc = -ENXIO; > + goto err; > + } > + dev_dbg(host, "%s: target: %d\n", dev_name(dport->dport), i); > + cxld->target[i] = dport; > + } > + device_unlock(&port->dev); > + > dev = &cxld->dev; > device_initialize(dev); > device_set_pm_not_required(dev); > @@ -519,14 +529,19 @@ 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 +565,32 @@ devm_cxl_add_decoder(struct device *host, struct > cxl_port *port, int nr_targets, > } > 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 > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h > index a9d4051722bf..1064427e3eb5 100644 > --- a/drivers/cxl/cxl.h > +++ b/drivers/cxl/cxl.h > @@ -180,6 +180,12 @@ enum cxl_decoder_type { > CXL_DECODER_EXPANDER = 3, > }; > > +/* > + * Current specification goes up to 8, double that seems a reasonable > + * software max for the foreseeable future > + */ > +#define CXL_DECODER_MAX_INTERLEAVE 16 > + > /** > * struct cxl_decoder - CXL address range decode configuration > * @dev: this decoder's device > @@ -284,22 +290,11 @@ 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); > - > -/* > - * 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. > - */ > -static inline struct cxl_decoder * > -devm_cxl_add_passthrough_decoder(struct device *host, struct cxl_port *port) > -{ > - return devm_cxl_add_decoder(host, port, 1, 0, 0, 1, PAGE_SIZE, > - CXL_DECODER_EXPANDER, 0); > -} > + enum cxl_decoder_type type, unsigned long flags, > + int *target_map); > > +struct cxl_decoder *devm_cxl_add_passthrough_decoder(struct device *host, > + struct cxl_port *port); > extern struct bus_type cxl_bus_type; > > struct cxl_driver { >
