Update Kconfig and runtime checks to better coordinate dax_cxl and dax_hmem
registration.
Add explicit Kconfig ordering so that CXL_ACPI and CXL_PCI must be
initialized before DEV_DAX_HMEM. This prevents dax_hmem from consuming
Soft Reserved ranges before CXL drivers have had a chance to claim them.
Replace IS_ENABLED(CONFIG_CXL_REGION) with IS_ENABLED(CONFIG_DEV_DAX_CXL)
so the code more precisely reflects when CXL-specific DAX coordination is
expected.
This ensures that ownership of Soft Reserved ranges is consistently
handed off to the CXL stack when DEV_DAX_CXL is configured.
Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@xxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/dax/Kconfig | 2 ++
drivers/dax/hmem/hmem.c | 2 +-
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
index d656e4c0eb84..3683bb3f2311 100644
--- a/drivers/dax/Kconfig
+++ b/drivers/dax/Kconfig
@@ -48,6 +48,8 @@ config DEV_DAX_CXL
tristate "CXL DAX: direct access to CXL RAM regions"
depends on CXL_BUS && CXL_REGION && DEV_DAX
default CXL_REGION && DEV_DAX
+ depends on CXL_ACPI >= DEV_DAX_HMEM
+ depends on CXL_PCI >= DEV_DAX_HMEM
help
CXL RAM regions are either mapped by platform-firmware
and published in the initial system-memory map as "System RAM", mapped
diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c
index 9277e5ea0019..7ada820cb177 100644
--- a/drivers/dax/hmem/hmem.c
+++ b/drivers/dax/hmem/hmem.c
@@ -66,7 +66,7 @@ static int hmem_register_device(struct device *host, int target_nid,
long id;
int rc;
- if (IS_ENABLED(CONFIG_CXL_REGION) &&
+ if (IS_ENABLED(CONFIG_DEV_DAX_CXL) &&
region_intersects(res->start, resource_size(res), IORESOURCE_MEM,
IORES_DESC_CXL) != REGION_DISJOINT) {
dev_dbg(host, "deferring range to CXL: %pr\n", res);
--
2.17.1
