diff mbox series

[v6,01/12] cxl/acpi: Simplify cxl_nvdimm_bridge probing

Message ID 166993040668.1882361.7450361097265836752.stgit@dwillia2-xfh.jf.intel.com
State Accepted
Commit cb9cfff82f6a862c1f54b8b01d9d9a979bb8ae78
Headers show
Series cxl: Add support for Restricted CXL hosts (RCD mode) | expand

Commit Message

Dan Williams Dec. 1, 2022, 9:33 p.m. UTC
The 'struct cxl_nvdimm_bridge' object advertises platform CXL PMEM
resources. It coordinates with libnvdimm to attach nvdimm devices and
regions for each corresponding CXL object. That coordination is
complicated, i.e. difficult to reason about, and it turns out redundant.
It is already the case that the CXL core knows how to tear down a
cxl_region when a cxl_memdev goes through ->remove(), so that pathway
can be extended to directly cleanup cxl_nvdimm and cxl_pmem_region
objects.

Towards the goal of ripping out the cxl_nvdimm_bridge state machine,
arrange for cxl_acpi to optionally pre-load the cxl_pmem driver so that
the nvdimm bridge is active synchronously with
devm_cxl_add_nvdimm_bridge(), and remove all the bind attributes for the
cxl_nvdimm* objects since the cxl root device and cxl_memdev bind
attributes are sufficient.

Tested-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/cxl/acpi.c |    1 +
 drivers/cxl/pmem.c |    9 +++++++++
 2 files changed, 10 insertions(+)

Comments

Jonathan Cameron Dec. 2, 2022, 3:02 p.m. UTC | #1
On Thu, 01 Dec 2022 13:33:26 -0800
Dan Williams <dan.j.williams@intel.com> wrote:

> The 'struct cxl_nvdimm_bridge' object advertises platform CXL PMEM
> resources. It coordinates with libnvdimm to attach nvdimm devices and
> regions for each corresponding CXL object. That coordination is
> complicated, i.e. difficult to reason about, and it turns out redundant.
> It is already the case that the CXL core knows how to tear down a
> cxl_region when a cxl_memdev goes through ->remove(), so that pathway
> can be extended to directly cleanup cxl_nvdimm and cxl_pmem_region
> objects.
> 
> Towards the goal of ripping out the cxl_nvdimm_bridge state machine,
> arrange for cxl_acpi to optionally pre-load the cxl_pmem driver so that
> the nvdimm bridge is active synchronously with
> devm_cxl_add_nvdimm_bridge(), and remove all the bind attributes for the
> cxl_nvdimm* objects since the cxl root device and cxl_memdev bind
> attributes are sufficient.
> 
> Tested-by: Robert Richter <rrichter@amd.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Seems reasonable and I can't see a disadvantage in doing this...
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>


> ---
>  drivers/cxl/acpi.c |    1 +
>  drivers/cxl/pmem.c |    9 +++++++++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
> index fb9f72813067..c540da0cbf1e 100644
> --- a/drivers/cxl/acpi.c
> +++ b/drivers/cxl/acpi.c
> @@ -539,3 +539,4 @@ module_platform_driver(cxl_acpi_driver);
>  MODULE_LICENSE("GPL v2");
>  MODULE_IMPORT_NS(CXL);
>  MODULE_IMPORT_NS(ACPI);
> +MODULE_SOFTDEP("pre: cxl_pmem");
> diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
> index 4c627d67281a..946e171e7d4a 100644
> --- a/drivers/cxl/pmem.c
> +++ b/drivers/cxl/pmem.c
> @@ -99,6 +99,9 @@ static struct cxl_driver cxl_nvdimm_driver = {
>  	.name = "cxl_nvdimm",
>  	.probe = cxl_nvdimm_probe,
>  	.id = CXL_DEVICE_NVDIMM,
> +	.drv = {
> +		.suppress_bind_attrs = true,
> +	},
>  };
>  
>  static int cxl_pmem_get_config_size(struct cxl_dev_state *cxlds,
> @@ -360,6 +363,9 @@ static struct cxl_driver cxl_nvdimm_bridge_driver = {
>  	.probe = cxl_nvdimm_bridge_probe,
>  	.remove = cxl_nvdimm_bridge_remove,
>  	.id = CXL_DEVICE_NVDIMM_BRIDGE,
> +	.drv = {
> +		.suppress_bind_attrs = true,
> +	},
>  };
>  
>  static int match_cxl_nvdimm(struct device *dev, void *data)
> @@ -583,6 +589,9 @@ static struct cxl_driver cxl_pmem_region_driver = {
>  	.name = "cxl_pmem_region",
>  	.probe = cxl_pmem_region_probe,
>  	.id = CXL_DEVICE_PMEM_REGION,
> +	.drv = {
> +		.suppress_bind_attrs = true,
> +	},
>  };
>  
>  /*
>
diff mbox series

Patch

diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index fb9f72813067..c540da0cbf1e 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -539,3 +539,4 @@  module_platform_driver(cxl_acpi_driver);
 MODULE_LICENSE("GPL v2");
 MODULE_IMPORT_NS(CXL);
 MODULE_IMPORT_NS(ACPI);
+MODULE_SOFTDEP("pre: cxl_pmem");
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index 4c627d67281a..946e171e7d4a 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -99,6 +99,9 @@  static struct cxl_driver cxl_nvdimm_driver = {
 	.name = "cxl_nvdimm",
 	.probe = cxl_nvdimm_probe,
 	.id = CXL_DEVICE_NVDIMM,
+	.drv = {
+		.suppress_bind_attrs = true,
+	},
 };
 
 static int cxl_pmem_get_config_size(struct cxl_dev_state *cxlds,
@@ -360,6 +363,9 @@  static struct cxl_driver cxl_nvdimm_bridge_driver = {
 	.probe = cxl_nvdimm_bridge_probe,
 	.remove = cxl_nvdimm_bridge_remove,
 	.id = CXL_DEVICE_NVDIMM_BRIDGE,
+	.drv = {
+		.suppress_bind_attrs = true,
+	},
 };
 
 static int match_cxl_nvdimm(struct device *dev, void *data)
@@ -583,6 +589,9 @@  static struct cxl_driver cxl_pmem_region_driver = {
 	.name = "cxl_pmem_region",
 	.probe = cxl_pmem_region_probe,
 	.id = CXL_DEVICE_PMEM_REGION,
+	.drv = {
+		.suppress_bind_attrs = true,
+	},
 };
 
 /*