Previously the target routing specifics of switch decoders were factored
out of 'struct cxl_decoder' into 'struct cxl_switch_decoder'.
This patch, 2 of 3, adds a 'struct cxl_root_decoder' as a superset of a
switch decoder that also track the associated CXL window platform
resource.
Note that the reason the resource for a given root decoder needs to be
looked up after the fact (i.e. after cxl_parse_cfmws() and
add_cxl_resource()) is because add_cxl_resource() may have merged CXL
windows in order to keep them at the top of the resource tree / decode
hierarchy.
Co-developed-by: Ben Widawsky <bwidawsk@xxxxxxxxxx>
Signed-off-by: Ben Widawsky <bwidawsk@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/cxl/acpi.c | 40 ++++++++++++++++++++++++++++++++++++----
drivers/cxl/core/port.c | 34 +++++++++++++++++++++++++++-------
drivers/cxl/cxl.h | 15 +++++++++++++--
3 files changed, 76 insertions(+), 13 deletions(-)
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index e2b6cbd04846..8f021241699f 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -84,7 +84,7 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg,
struct cxl_cfmws_context *ctx = arg;
struct cxl_port *root_port = ctx->root_port;
struct resource *cxl_res = ctx->cxl_res;
- struct cxl_switch_decoder *cxlsd;
+ struct cxl_root_decoder *cxlrd;
struct device *dev = ctx->dev;
struct acpi_cedt_cfmws *cfmws;
struct cxl_decoder *cxld;
@@ -128,11 +128,11 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg,
if (rc)
goto err_insert;
- cxlsd = cxl_root_decoder_alloc(root_port, ways);
- if (IS_ERR(cxld))
+ cxlrd = cxl_root_decoder_alloc(root_port, ways);
+ if (IS_ERR(cxlrd))
return 0;
- cxld = &cxlsd->cxld;
+ cxld = &cxlrd->cxlsd.cxld;
cxld->flags = cfmws_to_decoder_flags(cfmws->restrictions);
cxld->target_type = CXL_DECODER_EXPANDER;
cxld->hpa_range = (struct range) {
@@ -409,6 +409,32 @@ static int add_cxl_resources(struct resource *cxl_res)
return 0;
}
+static int pair_cxl_resource(struct device *dev, void *data)
+{
+ struct resource *cxl_res = data;
+ struct resource *p;
+
+ if (!is_root_decoder(dev))
+ return 0;
+
+ for (p = cxl_res->child; p; p = p->sibling) {
+ struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev);
+ struct cxl_decoder *cxld = &cxlrd->cxlsd.cxld;
+ struct resource res = {
+ .start = cxld->hpa_range.start,
+ .end = cxld->hpa_range.end,
+ .flags = IORESOURCE_MEM,
+ };
+
+ if (resource_contains(p, &res)) {
+ cxlrd->res = cxl_get_public_resource(p);
+ break;
+ }
+ }
+
+ return 0;
+}
+
static int cxl_acpi_probe(struct platform_device *pdev)
{
int rc;
@@ -459,6 +485,12 @@ static int cxl_acpi_probe(struct platform_device *pdev)
if (rc)
return rc;
+ /*
+ * Populate the root decoders with their related iomem resource,
+ * if present
+ */
+ device_for_each_child(&root_port->dev, cxl_res, pair_cxl_resource);
+
/*
* Root level scanned with host-bridge as dports, now scan host-bridges
* for their role as CXL uports to their CXL-capable PCIe Root Ports.
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 27a2a6b839aa..4953a1c7b245 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -260,6 +260,23 @@ static void cxl_switch_decoder_release(struct device *dev)
kfree(cxlsd);
}
+struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev)
+{
+ if (dev_WARN_ONCE(dev, !is_root_decoder(dev),
+ "not a cxl_root_decoder device\n"))
+ return NULL;
+ return container_of(dev, struct cxl_root_decoder, cxlsd.cxld.dev);
+}
+EXPORT_SYMBOL_NS_GPL(to_cxl_root_decoder, CXL);
+
+static void cxl_root_decoder_release(struct device *dev)
+{
+ struct cxl_root_decoder *cxlrd = to_cxl_root_decoder(dev);
+
+ __cxl_decoder_release(&cxlrd->cxlsd.cxld);
+ kfree(cxlrd);
+}
+
static const struct device_type cxl_decoder_endpoint_type = {
.name = "cxl_decoder_endpoint",
.release = cxl_decoder_release,
@@ -274,7 +291,7 @@ static const struct device_type cxl_decoder_switch_type = {
static const struct device_type cxl_decoder_root_type = {
.name = "cxl_decoder_root",
- .release = cxl_switch_decoder_release,
+ .release = cxl_root_decoder_release,
.groups = cxl_decoder_root_attribute_groups,
};
@@ -1271,9 +1288,10 @@ static int cxl_switch_decoder_init(struct cxl_port *port,
* firmware description of CXL resources into a CXL standard decode
* topology.
*/
-struct cxl_switch_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
- unsigned int nr_targets)
+struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
+ unsigned int nr_targets)
{
+ struct cxl_root_decoder *cxlrd;
struct cxl_switch_decoder *cxlsd;
struct cxl_decoder *cxld;
int rc;
@@ -1281,19 +1299,21 @@ struct cxl_switch_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
if (!is_cxl_root(port))
return ERR_PTR(-EINVAL);
- cxlsd = kzalloc(struct_size(cxlsd, target, nr_targets), GFP_KERNEL);
- if (!cxlsd)
+ cxlrd = kzalloc(struct_size(cxlrd, cxlsd.target, nr_targets),
+ GFP_KERNEL);
+ if (!cxlrd)
return ERR_PTR(-ENOMEM);
+ cxlsd = &cxlrd->cxlsd;
rc = cxl_switch_decoder_init(port, cxlsd, nr_targets);
if (rc) {
- kfree(cxlsd);
+ kfree(cxlrd);
return ERR_PTR(rc);
}
cxld = &cxlsd->cxld;
cxld->dev.type = &cxl_decoder_root_type;
- return cxlsd;
+ return cxlrd;
}
EXPORT_SYMBOL_NS_GPL(cxl_root_decoder_alloc, CXL);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 0289c06ec72c..ebdac8e7d181 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -260,6 +260,16 @@ struct cxl_switch_decoder {
};
+/**
+ * struct cxl_root_decoder - Static platform CXL address decoder
+ * @res: host / parent resource for region allocations
+ * @cxlsd: base cxl switch decoder
+ */
+struct cxl_root_decoder {
+ struct resource *res;
+ struct cxl_switch_decoder cxlsd;
+};
+
/**
* enum cxl_nvdimm_brige_state - state machine for managing bus rescans
* @CXL_NVB_NEW: Set at bridge create and after cxl_pmem_wq is destroyed
@@ -376,10 +386,11 @@ struct cxl_dport *cxl_find_dport_by_dev(struct cxl_port *port,
const struct device *dev);
struct cxl_decoder *to_cxl_decoder(struct device *dev);
+struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
bool is_root_decoder(struct device *dev);
bool is_endpoint_decoder(struct device *dev);
-struct cxl_switch_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
- unsigned int nr_targets);
+struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
+ unsigned int nr_targets);
struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
unsigned int nr_targets);
int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
