diff options
Diffstat (limited to 'drivers/cxl/core/region.c')
| -rw-r--r-- | drivers/cxl/core/region.c | 62 |
1 files changed, 46 insertions, 16 deletions
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index ce0e2d82bb2b4c..4c7fd2d5cccb29 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -730,12 +730,17 @@ static int match_auto_decoder(struct device *dev, void *data) return 0; } -static struct cxl_decoder *cxl_region_find_decoder(struct cxl_port *port, - struct cxl_region *cxlr) +static struct cxl_decoder * +cxl_region_find_decoder(struct cxl_port *port, + struct cxl_endpoint_decoder *cxled, + struct cxl_region *cxlr) { struct device *dev; int id = 0; + if (port == cxled_to_port(cxled)) + return &cxled->cxld; + if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) dev = device_find_child(&port->dev, &cxlr->params, match_auto_decoder); @@ -753,8 +758,31 @@ static struct cxl_decoder *cxl_region_find_decoder(struct cxl_port *port, return to_cxl_decoder(dev); } -static struct cxl_region_ref *alloc_region_ref(struct cxl_port *port, - struct cxl_region *cxlr) +static bool auto_order_ok(struct cxl_port *port, struct cxl_region *cxlr_iter, + struct cxl_decoder *cxld) +{ + struct cxl_region_ref *rr = cxl_rr_load(port, cxlr_iter); + struct cxl_decoder *cxld_iter = rr->decoder; + + /* + * Allow the out of order assembly of auto-discovered regions. + * Per CXL Spec 3.1 8.2.4.20.12 software must commit decoders + * in HPA order. Confirm that the decoder with the lesser HPA + * starting address has the lesser id. + */ + dev_dbg(&cxld->dev, "check for HPA violation %s:%d < %s:%d\n", + dev_name(&cxld->dev), cxld->id, + dev_name(&cxld_iter->dev), cxld_iter->id); + + if (cxld_iter->id > cxld->id) + return true; + + return false; +} + +static struct cxl_region_ref * +alloc_region_ref(struct cxl_port *port, struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled) { struct cxl_region_params *p = &cxlr->params; struct cxl_region_ref *cxl_rr, *iter; @@ -764,16 +792,21 @@ static struct cxl_region_ref *alloc_region_ref(struct cxl_port *port, xa_for_each(&port->regions, index, iter) { struct cxl_region_params *ip = &iter->region->params; - if (!ip->res) + if (!ip->res || ip->res->start < p->res->start) continue; - if (ip->res->start > p->res->start) { - dev_dbg(&cxlr->dev, - "%s: HPA order violation %s:%pr vs %pr\n", - dev_name(&port->dev), - dev_name(&iter->region->dev), ip->res, p->res); - return ERR_PTR(-EBUSY); + if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) { + struct cxl_decoder *cxld; + + cxld = cxl_region_find_decoder(port, cxled, cxlr); + if (auto_order_ok(port, iter->region, cxld)) + continue; } + dev_dbg(&cxlr->dev, "%s: HPA order violation %s:%pr vs %pr\n", + dev_name(&port->dev), + dev_name(&iter->region->dev), ip->res, p->res); + + return ERR_PTR(-EBUSY); } cxl_rr = kzalloc(sizeof(*cxl_rr), GFP_KERNEL); @@ -853,10 +886,7 @@ static int cxl_rr_alloc_decoder(struct cxl_port *port, struct cxl_region *cxlr, { struct cxl_decoder *cxld; - if (port == cxled_to_port(cxled)) - cxld = &cxled->cxld; - else - cxld = cxl_region_find_decoder(port, cxlr); + cxld = cxl_region_find_decoder(port, cxled, cxlr); if (!cxld) { dev_dbg(&cxlr->dev, "%s: no decoder available\n", dev_name(&port->dev)); @@ -953,7 +983,7 @@ static int cxl_port_attach_region(struct cxl_port *port, nr_targets_inc = true; } } else { - cxl_rr = alloc_region_ref(port, cxlr); + cxl_rr = alloc_region_ref(port, cxlr, cxled); if (IS_ERR(cxl_rr)) { dev_dbg(&cxlr->dev, "%s: failed to allocate region reference\n", |