---
drivers/cxl/core/hdm.c | 5
drivers/cxl/core/port.c | 2
drivers/cxl/core/region.c | 496 ++++++++++++++++++++++++++++++++++++++++++++-
drivers/cxl/cxl.h | 16 +
drivers/cxl/port.c | 26 ++
5 files changed, 531 insertions(+), 14 deletions(-)
diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
index dcc16d7cb8f3..174cddfec6e8 100644
--- a/drivers/cxl/core/hdm.c
+++ b/drivers/cxl/core/hdm.c
@@ -674,7 +674,7 @@ static int cxl_decoder_reset(struct cxl_decoder *cxld)
up_read(&cxl_dpa_rwsem);
port->commit_end--;
- cxld->flags &= ~CXL_DECODER_F_ENABLE;
+ cxld->flags &= ~(CXL_DECODER_F_ENABLE | CXL_DECODER_F_AUTO);
return 0;
}
@@ -719,7 +719,7 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
/* decoders are enabled if committed */
if (committed) {
- cxld->flags |= CXL_DECODER_F_ENABLE;
+ cxld->flags |= CXL_DECODER_F_ENABLE | CXL_DECODER_F_AUTO;
if (ctrl & CXL_HDM_DECODER0_CTRL_LOCK)
cxld->flags |= CXL_DECODER_F_LOCK;
if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl))
@@ -783,6 +783,7 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld,
return rc;
}
*dpa_base += dpa_size + skip;
+
return 0;
}
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 47e450c3a5a9..8130430ffbcf 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -446,6 +446,7 @@ bool is_endpoint_decoder(struct device *dev)
{
return dev->type == &cxl_decoder_endpoint_type;
}
+EXPORT_SYMBOL_NS_GPL(is_endpoint_decoder, CXL);
bool is_root_decoder(struct device *dev)
{
@@ -1622,6 +1623,7 @@ struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
}
cxlrd->calc_hb = calc_hb;
+ mutex_init(&cxlrd->range_lock);
cxld = &cxlsd->cxld;
cxld->dev.type = &cxl_decoder_root_type;
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index 34cf95217901..6fe8c70790df 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -6,6 +6,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/uuid.h>
+#include <linux/sort.h>
#include <linux/idr.h>
#include <cxlmem.h>
#include <cxl.h>
@@ -520,7 +521,12 @@ static void cxl_region_iomem_release(struct cxl_region *cxlr)
if (device_is_registered(&cxlr->dev))
lockdep_assert_held_write(&cxl_region_rwsem);
if (p->res) {
- remove_resource(p->res);
+ /*
+ * Autodiscovered regions may not have been able to insert their
+ * resource.
+ */
+ if (p->res->parent)
+ remove_resource(p->res);
kfree(p->res);
p->res = NULL;
}
@@ -1101,12 +1107,35 @@ static int cxl_port_setup_targets(struct cxl_port *port,
return rc;
}
- cxld->interleave_ways = iw;
- cxld->interleave_granularity = ig;
- cxld->hpa_range = (struct range) {
- .start = p->res->start,
- .end = p->res->end,
- };
+ if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) {
+ if (cxld->interleave_ways != iw ||
+ cxld->interleave_granularity != ig ||
+ cxld->hpa_range.start != p->res->start ||
+ cxld->hpa_range.end != p->res->end ||
+ ((cxld->flags & CXL_DECODER_F_ENABLE) == 0)) {
+ dev_err(&cxlr->dev,
+ "%s:%s %s expected iw: %d ig: %d %pr\n",
+ dev_name(port->uport), dev_name(&port->dev),
+ __func__, iw, ig, p->res);
+ dev_err(&cxlr->dev,
+ "%s:%s %s got iw: %d ig: %d state: %s %#llx:%#llx\n",
+ dev_name(port->uport), dev_name(&port->dev),
+ __func__, cxld->interleave_ways,
+ cxld->interleave_granularity,
+ (cxld->flags & CXL_DECODER_F_ENABLE) ?
+ "enabled" :
+ "disabled",
+ cxld->hpa_range.start, cxld->hpa_range.end);
+ return -ENXIO;
+ }
+ } else {
+ cxld->interleave_ways = iw;
+ cxld->interleave_granularity = ig;
+ cxld->hpa_range = (struct range) {
+ .start = p->res->start,
+ .end = p->res->end,
+ };
+ }
dev_dbg(&cxlr->dev, "%s:%s iw: %d ig: %d\n", dev_name(port->uport),
dev_name(&port->dev), iw, ig);
add_target:
@@ -1117,7 +1146,17 @@ static int cxl_port_setup_targets(struct cxl_port *port,
dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), pos);
return -ENXIO;
}
- cxlsd->target[cxl_rr->nr_targets_set] = ep->dport;
+ if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) {
+ if (cxlsd->target[cxl_rr->nr_targets_set] != ep->dport) {
+ dev_dbg(&cxlr->dev, "%s:%s: %s expected %s at %d\n",
+ dev_name(port->uport), dev_name(&port->dev),
+ dev_name(&cxlsd->cxld.dev),
+ dev_name(ep->dport->dport),
+ cxl_rr->nr_targets_set);
+ return -ENXIO;
+ }
+ } else
+ cxlsd->target[cxl_rr->nr_targets_set] = ep->dport;
inc = 1;
out_target_set:
cxl_rr->nr_targets_set += inc;
@@ -1159,6 +1198,13 @@ static void cxl_region_teardown_targets(struct cxl_region *cxlr)
struct cxl_ep *ep;
int i;
+ /*
+ * In the auto-discovery case skip automatic teardown since the
+ * address space is already active
+ */
+ if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags))
+ return;
+
for (i = 0; i < p->nr_targets; i++) {
cxled = p->targets[i];
cxlmd = cxled_to_memdev(cxled);
@@ -1191,8 +1237,8 @@ static int cxl_region_setup_targets(struct cxl_region *cxlr)
iter = to_cxl_port(iter->dev.parent);
/*
- * Descend the topology tree programming targets while
- * looking for conflicts.
+ * Descend the topology tree programming / validating
+ * targets while looking for conflicts.
*/
for (ep = cxl_ep_load(iter, cxlmd); iter;
iter = ep->next, ep = cxl_ep_load(iter, cxlmd)) {
@@ -1287,6 +1333,182 @@ static int cxl_region_attach_position(struct cxl_region *cxlr,
return rc;
}
+static int cxl_region_attach_auto(struct cxl_region *cxlr,
+ struct cxl_endpoint_decoder *cxled, int pos)
+{
+ struct cxl_region_params *p = &cxlr->params;
+
+ if (!(cxled->cxld.flags & CXL_DECODER_F_AUTO)) {
+ dev_err(&cxlr->dev,
+ "%s: unable to add decoder to autodetected region\n",
+ dev_name(&cxled->cxld.dev));
+ return -EINVAL;
+ }
+
+ if (pos >= 0) {
+ dev_dbg(&cxlr->dev, "%s: expected auto position, not %d\n",
+ dev_name(&cxled->cxld.dev), pos);
+ return -EINVAL;
+ }
+
+ if (p->nr_targets >= p->interleave_ways) {
+ dev_err(&cxlr->dev, "%s: no more target slots available\n",
+ dev_name(&cxled->cxld.dev));
+ return -ENXIO;
+ }
+
+ /*
+ * Temporarily record the endpoint decoder into the target array. Yes,
+ * this means that userspace can view devices in the wrong position
+ * before the region activates, and must be careful to understand when
+ * it might be racing region autodiscovery.
+ */
+ pos = p->nr_targets;
+ p->targets[pos] = cxled;
+ cxled->pos = pos;
+ p->nr_targets++;
+
+ return 0;
+}
+
+static struct cxl_port *next_port(struct cxl_port *port)
+{
+ if (!port->parent_dport)
+ return NULL;
+ return port->parent_dport->port;
+}
+
+static int decoder_match_range(struct device *dev, void *data)
+{
+ struct cxl_endpoint_decoder *cxled = data;
+ struct cxl_switch_decoder *cxlsd;
+
+ if (!is_switch_decoder(dev))
+ return 0;
+
+ cxlsd = to_cxl_switch_decoder(dev);
+ return range_contains(&cxlsd->cxld.hpa_range, &cxled->cxld.hpa_range);
+}
+
+static void find_positions(const struct cxl_switch_decoder *cxlsd,
+ const struct cxl_port *iter_a,
+ const struct cxl_port *iter_b, int *a_pos,
+ int *b_pos)
+{
+ int i;
+
+ for (i = 0, *a_pos = -1, *b_pos = -1; i < cxlsd->nr_targets; i++) {
+ if (cxlsd->target[i] == iter_a->parent_dport)
+ *a_pos = i;
+ else if (cxlsd->target[i] == iter_b->parent_dport)
+ *b_pos = i;
+ if (*a_pos >= 0 && *b_pos >= 0)
+ break;
+ }
+}
+
+static int cmp_decode_pos(const void *a, const void *b)
+{
+ struct cxl_endpoint_decoder *cxled_a = *(typeof(cxled_a) *)a;
+ struct cxl_endpoint_decoder *cxled_b = *(typeof(cxled_b) *)b;
+ struct cxl_memdev *cxlmd_a = cxled_to_memdev(cxled_a);
+ struct cxl_memdev *cxlmd_b = cxled_to_memdev(cxled_b);
+ struct cxl_port *port_a = cxled_to_port(cxled_a);
+ struct cxl_port *port_b = cxled_to_port(cxled_b);
+ struct cxl_port *iter_a, *iter_b;
+
+ /* Exit early if any prior sorting failed */
+ if (cxled_a->pos < 0 || cxled_b->pos < 0)
+ return 0;
+
+ /*
+ * Walk up the hierarchy to find a shared port, find the decoder
+ * that maps the range, compare the relative position of those
+ * dport mappings.
+ */
+ for (iter_a = port_a; iter_a; iter_a = next_port(iter_a)) {
+ struct cxl_port *next_a, *next_b, *port;
+ struct cxl_switch_decoder *cxlsd;
+
+ next_a = next_port(iter_a);
+ for (iter_b = port_b; iter_b; iter_b = next_port(iter_b)) {
+ int a_pos, b_pos, result;
+ struct device *dev;
+ unsigned int seq;
+
+ next_b = next_port(iter_b);
+ if (next_a != next_b)
+ continue;
+ if (!next_a)
+ goto out;
+ port = next_a;
+ dev = device_find_child(&port->dev, cxled_a,
+ decoder_match_range);
+ if (!dev) {
+ struct range *range = &cxled_a->cxld.hpa_range;
+
+ dev_err(port->uport,
+ "failed to find decoder that maps %#llx-:%#llx\n",
+ range->start, range->end);
+ cxled_a->pos = -1;
+ return 0;
+ }
+
+ cxlsd = to_cxl_switch_decoder(dev);
+ do {
+ seq = read_seqbegin(&cxlsd->target_lock);
+ find_positions(cxlsd, iter_a, iter_b, &a_pos,
+ &b_pos);
+ } while (read_seqretry(&cxlsd->target_lock, seq));
+
+ if (a_pos < 0 || b_pos < 0) {
+ dev_err(port->uport,
+ "failed to find shared decoder for %s and %s\n",
+ dev_name(cxlmd_a->dev.parent),
+ dev_name(cxlmd_b->dev.parent));
+ cxled_a->pos = -1;
+ result = 0;
+ } else {
+ result = a_pos - b_pos;
+ dev_dbg(port->uport, "%s: %s comes %s %s\n",
+ dev_name(&cxlsd->cxld.dev),
+ dev_name(cxlmd_a->dev.parent),
+ result < 0 ? "before" : "after",
+ dev_name(cxlmd_b->dev.parent));
+ }
+
+ put_device(dev);
+
+ return result;
+ }
+ }
+out:
+ dev_err(cxlmd_a->dev.parent, "failed to find shared port with %s\n",
+ dev_name(cxlmd_b->dev.parent));
+ cxled_a->pos = -1;
+ return 0;
+}
+
+static int cxl_region_sort_targets(struct cxl_region *cxlr)
+{
+ struct cxl_region_params *p = &cxlr->params;
+ int i, rc = 0;
+
+ sort(p->targets, p->nr_targets, sizeof(p->targets[0]), cmp_decode_pos,
+ NULL);
+
+ for (i = 0; i < p->nr_targets; i++) {
+ struct cxl_endpoint_decoder *cxled = p->targets[i];
+
+ if (cxled->pos < 0)
+ rc = -ENXIO;
+ cxled->pos = i;
+ }
+
+ dev_dbg(&cxlr->dev, "region sort %s\n", rc ? "failed" : "successful");
+ return rc;
+}
+
static int cxl_region_attach(struct cxl_region *cxlr,
struct cxl_endpoint_decoder *cxled, int pos)
{
@@ -1350,6 +1572,50 @@ static int cxl_region_attach(struct cxl_region *cxlr,
return -EINVAL;
}
+ if (test_bit(CXL_REGION_F_AUTO, &cxlr->flags)) {
+ int i;
+
+ rc = cxl_region_attach_auto(cxlr, cxled, pos);
+ if (rc)
+ return rc;
+
+ /* await more targets to arrive... */
+ if (p->nr_targets < p->interleave_ways)
+ return 0;
+
+ /*
+ * All targets are here, which implies all PCI enumeration that
+ * affects this region has been completed. Walk the topology to
+ * sort the devices into their relative region decode position.
+ */
+ rc = cxl_region_sort_targets(cxlr);
+ if (rc)
+ return rc;
+
+ for (i = 0; i < p->nr_targets; i++) {
+ cxled = p->targets[i];
+ ep_port = cxled_to_port(cxled);
+ dport = cxl_find_dport_by_dev(root_port,
+ ep_port->host_bridge);
+ rc = cxl_region_attach_position(cxlr, cxlrd, cxled,
+ dport, i);
+ if (rc)
+ return rc;
+ }
+
+ rc = cxl_region_setup_targets(cxlr);
+ if (rc)
+ return rc;
+
+ /*
+ * If target setup succeeds in the autodiscovery case
+ * then the region is already committed.
+ */
+ p->state = CXL_CONFIG_COMMIT;
+
+ return 0;
+ }
+
rc = cxl_region_validate_position(cxlr, cxled, pos);
if (rc)
return rc;
@@ -1500,8 +1766,8 @@ static int detach_target(struct cxl_region *cxlr, int pos)
return rc;
}
-static size_t store_targetN(struct cxl_region *cxlr, const char *buf, int pos,
- size_t len)
+static ssize_t store_targetN(struct cxl_region *cxlr, const char *buf, int pos,
+ size_t len)
{
int rc;
@@ -2079,6 +2345,191 @@ static int devm_cxl_add_pmem_region(struct cxl_region *cxlr)
return rc;
}
+static int match_decoder_by_range(struct device *dev, void *data)
+{
+ struct range *r1, *r2 = data;
+ struct cxl_root_decoder *cxlrd;
+
+ if (!is_root_decoder(dev))
+ return 0;
+
+ cxlrd = to_cxl_root_decoder(dev);
+ r1 = &cxlrd->cxlsd.cxld.hpa_range;
+ return range_contains(r1, r2);
+}
+
+static int match_region_by_range(struct device *dev, void *data)
+{
+ struct cxl_region_params *p;
+ struct cxl_region *cxlr;
+ struct range *r = data;
+ int rc = 0;
+
+ if (!is_cxl_region(dev))
+ return 0;
+
+ cxlr = to_cxl_region(dev);
+ p = &cxlr->params;
+
+ down_read(&cxl_region_rwsem);
+ if (p->res && p->res->start == r->start && p->res->end == r->end)
+ rc = 1;
+ up_read(&cxl_region_rwsem);
+
+ return rc;
+}
+
+/* Establish an empty region covering the given HPA range */
+static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
+ struct cxl_endpoint_decoder *cxled)
+{
+ struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+ struct cxl_port *port = cxlrd_to_port(cxlrd);
+ struct range *hpa = &cxled->cxld.hpa_range;
+ struct cxl_region_params *p;
+ struct cxl_region *cxlr;
+ struct resource *res;
+ int rc;
+
+ do {
+ cxlr = __create_region(cxlrd, cxled->mode,
+ atomic_read(&cxlrd->region_id));
+ } while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY);
+
+ if (IS_ERR(cxlr)) {
+ dev_err(cxlmd->dev.parent,
+ "%s:%s: %s failed assign region: %ld\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ __func__, PTR_ERR(cxlr));
+ return cxlr;
+ }
+
+ down_write(&cxl_region_rwsem);
+ p = &cxlr->params;
+ if (p->state >= CXL_CONFIG_INTERLEAVE_ACTIVE) {
+ dev_err(cxlmd->dev.parent,
+ "%s:%s: %s autodiscovery interrupted\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ __func__);
+ rc = -EBUSY;
+ goto err;
+ }
+
+ set_bit(CXL_REGION_F_AUTO, &cxlr->flags);
+
+ res = kmalloc(sizeof(*res), GFP_KERNEL);
+ if (!res) {
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ *res = DEFINE_RES_MEM_NAMED(hpa->start, range_len(hpa),
+ dev_name(&cxlr->dev));
+ rc = insert_resource(cxlrd->res, res);
+ if (rc) {
+ /*
+ * Platform-firmware may not have split resources like "System
+ * RAM" on CXL window boundaries see cxl_region_iomem_release()
+ */
+ dev_warn(cxlmd->dev.parent,
+ "%s:%s: %s %s cannot insert resource\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev),
+ __func__, dev_name(&cxlr->dev));
+ }
+
+ p->res = res;
+ p->interleave_ways = cxled->cxld.interleave_ways;
+ p->interleave_granularity = cxled->cxld.interleave_granularity;
+ p->state = CXL_CONFIG_INTERLEAVE_ACTIVE;
+
+ rc = sysfs_update_group(&cxlr->dev.kobj, get_cxl_region_target_group());
+ if (rc)
+ goto err;
+
+ dev_dbg(cxlmd->dev.parent, "%s:%s: %s %s res: %pr iw: %d ig: %d\n",
+ dev_name(&cxlmd->dev), dev_name(&cxled->cxld.dev), __func__,
+ dev_name(&cxlr->dev), p->res, p->interleave_ways,
+ p->interleave_granularity);
+
+ /* ...to match put_device() in cxl_add_to_region() */
+ get_device(&cxlr->dev);
+ up_write(&cxl_region_rwsem);
+
+ return cxlr;
+
+err:
+ up_write(&cxl_region_rwsem);
+ devm_release_action(port->uport, unregister_region, cxlr);
+ return ERR_PTR(rc);
+}
+
+void cxl_add_to_region(struct cxl_endpoint_decoder *cxled)
+{
+ struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
+ struct range *hpa = &cxled->cxld.hpa_range;
+ struct cxl_decoder *cxld = &cxled->cxld;
+ struct cxl_root_decoder *cxlrd;
+ struct cxl_region_params *p;
+ struct cxl_region *cxlr;
+ struct cxl_port *root;
+ bool attach = false;
+ struct device *dev;
+
+ root = find_cxl_root(&cxlmd->dev);
+ if (!root) {
+ dev_err(cxlmd->dev.parent, "%s: failed to map CXL root\n",
+ dev_name(&cxlmd->dev));
+ return;
+ }
+
+ dev = device_find_child(&root->dev, &cxld->hpa_range,
+ match_decoder_by_range);
+ if (!dev) {
+ dev_err(cxlmd->dev.parent,
+ "%s:%s no CXL window for range %#llx:%#llx\n",
+ dev_name(&cxlmd->dev), dev_name(&cxld->dev),
+ cxld->hpa_range.start, cxld->hpa_range.end);
+ goto out;
+ }
+ cxlrd = to_cxl_root_decoder(dev);
+
+ mutex_lock(&cxlrd->range_lock);
+ dev = device_find_child(&cxlrd->cxlsd.cxld.dev, hpa,
+ match_region_by_range);
+ if (!dev)
+ cxlr = construct_region(cxlrd, cxled);
+ else
+ cxlr = to_cxl_region(dev);
+ mutex_unlock(&cxlrd->range_lock);
+
+ if (IS_ERR(cxlr))
+ goto out;
+
+ attach_target(cxlr, cxled, -1, TASK_UNINTERRUPTIBLE);
+
+ down_read(&cxl_region_rwsem);
+ p = &cxlr->params;
+ attach = p->state >= CXL_CONFIG_COMMIT;
+ up_read(&cxl_region_rwsem);
+
+ if (attach) {
+ int rc = device_attach(&cxlr->dev);
+
+ /*
+ * If device_attach() fails the range may still be
+ * active via the platform-firmware memory map
+ */
+ if (rc < 0)
+ dev_err(&cxlr->dev, "failed to enable, range: %pr\n",
+ p->res);
+ }
+
+ put_device(&cxlr->dev);
+out:
+ put_device(&root->dev);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_add_to_region, CXL);
+
static int cxl_region_invalidate_memregion(struct cxl_region *cxlr)
{
if (!test_bit(CXL_REGION_F_INCOHERENT, &cxlr->flags))
@@ -2103,6 +2554,15 @@ static int cxl_region_invalidate_memregion(struct cxl_region *cxlr)
return 0;
}
+static int is_system_ram(struct resource *res, void *arg)
+{
+ struct cxl_region *cxlr = arg;
+ struct cxl_region_params *p = &cxlr->params;
+
+ dev_dbg(&cxlr->dev, "%pr has System RAM: %pr\n", p->res, res);
+ return 1;
+}
+
static int cxl_region_probe(struct device *dev)
{
struct cxl_region *cxlr = to_cxl_region(dev);
@@ -2136,6 +2596,18 @@ static int cxl_region_probe(struct device *dev)
switch (cxlr->mode) {
case CXL_DECODER_PMEM:
return devm_cxl_add_pmem_region(cxlr);
+ case CXL_DECODER_RAM:
+ /*
+ * The region can not be manged by CXL if any portion of
+ * it is already online as 'System RAM'
+ */
+ if (walk_iomem_res_desc(IORES_DESC_NONE,
+ IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
+ p->res->start, p->res->end, cxlr,
+ is_system_ram) > 0)
+ return 0;
+ dev_dbg(dev, "TODO: hookup devdax\n");
+ return 0;
default:
dev_dbg(&cxlr->dev, "unsupported region mode: %d\n",
cxlr->mode);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index ca76879af1de..9b3765c5c81a 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -261,6 +261,8 @@ resource_size_t cxl_rcrb_to_component(struct device *dev,
* cxl_decoder flags that define the type of memory / devices this
* decoder supports as well as configuration lock status See "CXL 2.0
* 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
+ * Additionally indicate whether decoder settings were autodetected,
+ * user customized.
*/
#define CXL_DECODER_F_RAM BIT(0)
#define CXL_DECODER_F_PMEM BIT(1)
@@ -268,6 +270,7 @@ resource_size_t cxl_rcrb_to_component(struct device *dev,
#define CXL_DECODER_F_TYPE3 BIT(3)
#define CXL_DECODER_F_LOCK BIT(4)
#define CXL_DECODER_F_ENABLE BIT(5)
+#define CXL_DECODER_F_AUTO BIT(6)
#define CXL_DECODER_F_MASK GENMASK(5, 0)
enum cxl_decoder_type {
@@ -380,6 +383,7 @@ typedef struct cxl_dport *(*cxl_calc_hb_fn)(struct cxl_root_decoder *cxlrd,
* @region_id: region id for next region provisioning event
* @calc_hb: which host bridge covers the n'th position by granularity
* @platform_data: platform specific configuration data
+ * @range_lock: sync region autodiscovery by address range
* @cxlsd: base cxl switch decoder
*/
struct cxl_root_decoder {
@@ -387,6 +391,7 @@ struct cxl_root_decoder {
atomic_t region_id;
cxl_calc_hb_fn calc_hb;
void *platform_data;
+ struct mutex range_lock;
struct cxl_switch_decoder cxlsd;
};
@@ -436,6 +441,13 @@ struct cxl_region_params {
*/
#define CXL_REGION_F_INCOHERENT 0
+/*
+ * Indicate whether this region has been assembled by autodetection or
+ * userspace assembly. Prevent endpoint decoders outside of automatic
+ * detection from being added to the region.
+ */
+#define CXL_REGION_F_AUTO 1
+
/**
* struct cxl_region - CXL region
* @dev: This region's device
@@ -699,6 +711,7 @@ struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *dev);
#ifdef CONFIG_CXL_REGION
bool is_cxl_pmem_region(struct device *dev);
struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
+void cxl_add_to_region(struct cxl_endpoint_decoder *cxled);
#else
static inline bool is_cxl_pmem_region(struct device *dev)
{
@@ -708,6 +721,9 @@ static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
{
return NULL;
}
+static inline void cxl_add_to_region(struct cxl_endpoint_decoder *cxled)
+{
+}
#endif
/*
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index 5453771bf330..012a0c6f8476 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -30,6 +30,23 @@ static void schedule_detach(void *cxlmd)
schedule_cxl_memdev_detach(cxlmd);
}
+static int discover_region(struct device *dev, void *data)
+{
+ const unsigned long flags = CXL_DECODER_F_ENABLE | CXL_DECODER_F_AUTO;
+ struct cxl_endpoint_decoder *cxled;
+
+ if (!is_endpoint_decoder(dev))
+ return 0;
+
+ cxled = to_cxl_endpoint_decoder(dev);
+ if ((cxled->cxld.flags & flags) != flags)
+ return 0;
+
+ cxl_add_to_region(cxled);
+
+ return 0;
+}
+
static int cxl_port_probe(struct device *dev)
{
struct cxl_port *port = to_cxl_port(dev);
@@ -78,6 +95,15 @@ static int cxl_port_probe(struct device *dev)
return rc;
}
+ if (!is_cxl_endpoint(port))
+ return 0;
+
+ /*
+ * Now that all endpoint decoders are successfully enumerated,
+ * try to assemble regions from committed decoders
+ */
+ device_for_each_child(dev, NULL, discover_region);
+
return 0;
}