[PATCH 3/5] cxl/acpi: Add platform flag for HPA address translation

From: Robert Richter
Date: Thu Jun 27 2024 - 18:47:24 EST


Adding an early check to detect platform specifics to (later) enable
HPA address translation. The cxl_root structure is used to store that
information.

Note: The platform check will be added later when enabling address
translation.

Link: https://lore.kernel.org/all/65c68969903b1_afa429460@xxxxxxxxxxxxxxxxxxxxxxxxx.notmuch/
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Robert Richter <rrichter@xxxxxxx>
---
drivers/cxl/acpi.c | 7 +++++++
drivers/cxl/cxl.h | 2 ++
2 files changed, 9 insertions(+)

diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index 571069863c62..67f73a831bd3 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -536,6 +536,11 @@ static int cxl_get_chbs(struct device *dev, struct acpi_device *hb,
return 0;
}

+static void setup_platform_quirks(struct cxl_root *root)
+{
+ root->hpa_xlat_enable = 0;
+}
+
static int get_genport_coordinates(struct device *dev, struct cxl_dport *dport)
{
struct acpi_device *hb = to_cxl_host_bridge(NULL, dev);
@@ -838,6 +843,8 @@ static int cxl_acpi_probe(struct platform_device *pdev)
return PTR_ERR(cxl_root);
root_port = &cxl_root->port;

+ setup_platform_quirks(cxl_root);
+
rc = bus_for_each_dev(adev->dev.bus, NULL, root_port,
add_host_bridge_dport);
if (rc < 0)
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 603c0120cff8..95d054dc1af0 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -627,10 +627,12 @@ struct cxl_port {
*
* @port: cxl_port member
* @ops: cxl root operations
+ * @hpa_xlat_enable: enable HPA translation
*/
struct cxl_root {
struct cxl_port port;
const struct cxl_root_ops *ops;
+ bool hpa_xlat_enable;
};

static inline struct cxl_root *
--
2.39.2