diff mbox series

[v6,11/12] tools/testing/cxl: Add an RCH topology

Message ID 166993046170.1882361.12460762475782283638.stgit@dwillia2-xfh.jf.intel.com (mailing list archive)
State Accepted
Commit c9435dbee119f42132af2c3fc0382d16bda32601
Headers show
Series cxl: Add support for Restricted CXL hosts (RCD mode) | expand

Commit Message

Dan Williams Dec. 1, 2022, 9:34 p.m. UTC
In an RCH topology a CXL host-bridge as Root Complex Integrated Endpoint
the represents the memory expander. Unlike a VH topology there is no
CXL/PCIE Root Port that host the endpoint. The CXL subsystem maps this
as the CXL root object (ACPI0017 on ACPI based systems) targeting the
host-bridge as a dport, per usual, but then that dport directly hosts
the endpoint port.

Mock up that configuration with a 4th host-bridge that has a 'cxl_rcd'
device instance as its immediate child.

Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 tools/testing/cxl/test/cxl.c |  151 +++++++++++++++++++++++++++++++++++++++---
 tools/testing/cxl/test/mem.c |   37 ++++++++++
 2 files changed, 176 insertions(+), 12 deletions(-)

Comments

Robert Richter Dec. 2, 2022, 8:05 a.m. UTC | #1
On 01.12.22 13:34:21, Dan Williams wrote:
> In an RCH topology a CXL host-bridge as Root Complex Integrated Endpoint
> the represents the memory expander. Unlike a VH topology there is no
> CXL/PCIE Root Port that host the endpoint. The CXL subsystem maps this
> as the CXL root object (ACPI0017 on ACPI based systems) targeting the
> host-bridge as a dport, per usual, but then that dport directly hosts
> the endpoint port.
> 
> Mock up that configuration with a 4th host-bridge that has a 'cxl_rcd'
> device instance as its immediate child.
> 
> Reviewed-by: Alison Schofield <alison.schofield@intel.com>

Reviewed-by: Robert Richter <rrichter@amd.com>

> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  tools/testing/cxl/test/cxl.c |  151 +++++++++++++++++++++++++++++++++++++++---
>  tools/testing/cxl/test/mem.c |   37 ++++++++++
>  2 files changed, 176 insertions(+), 12 deletions(-)
Jonathan Cameron Dec. 2, 2022, 5:04 p.m. UTC | #2
On Thu, 01 Dec 2022 13:34:21 -0800
Dan Williams <dan.j.williams@intel.com> wrote:

> In an RCH topology a CXL host-bridge as Root Complex Integrated Endpoint
> the represents the memory expander. Unlike a VH topology there is no
> CXL/PCIE Root Port that host the endpoint. The CXL subsystem maps this
> as the CXL root object (ACPI0017 on ACPI based systems) targeting the
> host-bridge as a dport, per usual, but then that dport directly hosts
> the endpoint port.
> 
> Mock up that configuration with a 4th host-bridge that has a 'cxl_rcd'
> device instance as its immediate child.
> 
> Reviewed-by: Alison Schofield <alison.schofield@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

A few trivial things inline.  

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>



> -static struct pci_bus mock_pci_bus[NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST];
> +static struct pci_bus mock_pci_bus[NR_BRIDGES];
>  static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
>  	[0] = {
>  		.bus = &mock_pci_bus[0],
> @@ -452,7 +493,9 @@ static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
>  	[2] = {
>  		.bus = &mock_pci_bus[2],
>  	},
> -

I guess fixing this stray space here is fine to avoid a rebase to tidy it up
in original patch which you have on your next branch.

> +	[3] = {
> +		.bus = &mock_pci_bus[3],
> +	},
>  };
>  
>  static bool is_mock_bus(struct pci_bus *bus)
> @@ -738,6 +781,87 @@ static void mock_companion(struct acpi_device *adev, struct device *dev)
>  #define SZ_512G (SZ_64G * 8)
>  #endif
>  
> +static __init int cxl_rch_init(void)
> +{
> +	int rc, i;
> +
> +	for (i = 0; i < ARRAY_SIZE(cxl_rch); i++) {
> +		int idx = NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST + i;
> +		struct acpi_device *adev = &host_bridge[idx];
> +		struct platform_device *pdev;
> +
> +		pdev = platform_device_alloc("cxl_host_bridge", idx);
> +		if (!pdev)
> +			goto err_bridge;
> +
> +		mock_companion(adev, &pdev->dev);
> +		rc = platform_device_add(pdev);
> +		if (rc) {
> +			platform_device_put(pdev);
> +			goto err_bridge;
> +		}
> +
> +		cxl_rch[i] = pdev;

Reason for this suggestion is below.
Move down cxl_rch[i] = pdev;...

> +		mock_pci_bus[idx].bridge = &pdev->dev;
> +		rc = sysfs_create_link(&pdev->dev.kobj, &pdev->dev.kobj,
> +				       "firmware_node");
> +		if (rc)
> +			goto err_bridge;

to here, and clean up this single loop iteration by having a 
platform_device_unregister in the error path above.

> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
> +		int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
> +		struct platform_device *rch = cxl_rch[i];
> +		struct platform_device *pdev;
> +
> +		pdev = platform_device_alloc("cxl_rcd", idx);
> +		if (!pdev)
> +			goto err_mem;
> +		pdev->dev.parent = &rch->dev;
> +		set_dev_node(&pdev->dev, i % 2);
> +
> +		rc = platform_device_add(pdev);
> +		if (rc) {
> +			platform_device_put(pdev);
> +			goto err_mem;
> +		}
> +		cxl_rcd[i] = pdev;
> +	}
> +
> +	return 0;
> +
> +err_mem:
> +	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
> +		platform_device_unregister(cxl_rcd[i]);
> +err_bridge:
> +	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
> +		struct platform_device *pdev = cxl_rch[i];
> +
> +		if (!pdev)
> +			continue;
> +		sysfs_remove_link(&pdev->dev.kobj, "firmware_node");

Had to look up that this was safe if the file doesn't exist (it is)
I'd rather not have to check, so maybe make the sysfs path
above clean up the device in the loop iteration and only set
cxl_rch[i] once the loop iteration can't fail?  See above.

To my mind doing it that way is more 'obviously correct'
which is never a bad thing.

> +		platform_device_unregister(cxl_rch[i]);
> +	}
> +
> +	return rc;
> +}
> +
> +static void cxl_rch_exit(void)
> +{
> +	int i;
> +
> +	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
> +		platform_device_unregister(cxl_rcd[i]);
> +	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
> +		struct platform_device *pdev = cxl_rch[i];
> +
> +		if (!pdev)
> +			continue;
> +		sysfs_remove_link(&pdev->dev.kobj, "firmware_node");
> +		platform_device_unregister(cxl_rch[i]);
> +	}
> +}
> +
Dan Williams Dec. 3, 2022, 7:50 a.m. UTC | #3
Jonathan Cameron wrote:
> On Thu, 01 Dec 2022 13:34:21 -0800
> Dan Williams <dan.j.williams@intel.com> wrote:
> 
> > In an RCH topology a CXL host-bridge as Root Complex Integrated Endpoint
> > the represents the memory expander. Unlike a VH topology there is no
> > CXL/PCIE Root Port that host the endpoint. The CXL subsystem maps this
> > as the CXL root object (ACPI0017 on ACPI based systems) targeting the
> > host-bridge as a dport, per usual, but then that dport directly hosts
> > the endpoint port.
> > 
> > Mock up that configuration with a 4th host-bridge that has a 'cxl_rcd'
> > device instance as its immediate child.
> > 
> > Reviewed-by: Alison Schofield <alison.schofield@intel.com>
> > Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> 
> A few trivial things inline.  
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> 
> 
> 
> > -static struct pci_bus mock_pci_bus[NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST];
> > +static struct pci_bus mock_pci_bus[NR_BRIDGES];
> >  static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
> >  	[0] = {
> >  		.bus = &mock_pci_bus[0],
> > @@ -452,7 +493,9 @@ static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
> >  	[2] = {
> >  		.bus = &mock_pci_bus[2],
> >  	},
> > -
> 
> I guess fixing this stray space here is fine to avoid a rebase to tidy it up
> in original patch which you have on your next branch.

In fact it's already upstream in v6.1-rc4 unfortunately, but it has no
business being in this patch.

So the hunk is now:

@@ -452,6 +493,9 @@ static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
        [2] = {
                .bus = &mock_pci_bus[2],
        },
+       [3] = {
+               .bus = &mock_pci_bus[3],
+       },
 
 };
 
> 
> > +	[3] = {
> > +		.bus = &mock_pci_bus[3],
> > +	},
> >  };
> >  
> >  static bool is_mock_bus(struct pci_bus *bus)
> > @@ -738,6 +781,87 @@ static void mock_companion(struct acpi_device *adev, struct device *dev)
> >  #define SZ_512G (SZ_64G * 8)
> >  #endif
> >  
> > +static __init int cxl_rch_init(void)
> > +{
> > +	int rc, i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(cxl_rch); i++) {
> > +		int idx = NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST + i;
> > +		struct acpi_device *adev = &host_bridge[idx];
> > +		struct platform_device *pdev;
> > +
> > +		pdev = platform_device_alloc("cxl_host_bridge", idx);
> > +		if (!pdev)
> > +			goto err_bridge;
> > +
> > +		mock_companion(adev, &pdev->dev);
> > +		rc = platform_device_add(pdev);
> > +		if (rc) {
> > +			platform_device_put(pdev);
> > +			goto err_bridge;
> > +		}
> > +
> > +		cxl_rch[i] = pdev;
> 
> Reason for this suggestion is below.
> Move down cxl_rch[i] = pdev;...
> 
> > +		mock_pci_bus[idx].bridge = &pdev->dev;
> > +		rc = sysfs_create_link(&pdev->dev.kobj, &pdev->dev.kobj,
> > +				       "firmware_node");
> > +		if (rc)
> > +			goto err_bridge;
> 
> to here, and clean up this single loop iteration by having a 
> platform_device_unregister in the error path above.

Ok, makes sense.

> 
> > +	}
> > +
> > +	for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
> > +		int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
> > +		struct platform_device *rch = cxl_rch[i];
> > +		struct platform_device *pdev;
> > +
> > +		pdev = platform_device_alloc("cxl_rcd", idx);
> > +		if (!pdev)
> > +			goto err_mem;
> > +		pdev->dev.parent = &rch->dev;
> > +		set_dev_node(&pdev->dev, i % 2);
> > +
> > +		rc = platform_device_add(pdev);
> > +		if (rc) {
> > +			platform_device_put(pdev);
> > +			goto err_mem;
> > +		}
> > +		cxl_rcd[i] = pdev;
> > +	}
> > +
> > +	return 0;
> > +
> > +err_mem:
> > +	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
> > +		platform_device_unregister(cxl_rcd[i]);
> > +err_bridge:
> > +	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
> > +		struct platform_device *pdev = cxl_rch[i];
> > +
> > +		if (!pdev)
> > +			continue;
> > +		sysfs_remove_link(&pdev->dev.kobj, "firmware_node");
> 
> Had to look up that this was safe if the file doesn't exist (it is)
> I'd rather not have to check, so maybe make the sysfs path
> above clean up the device in the loop iteration and only set
> cxl_rch[i] once the loop iteration can't fail?  See above.
> 
> To my mind doing it that way is more 'obviously correct'
> which is never a bad thing.

So this also dovetails with Robert's feedback to move this error exit
block to just call cxl_rch_exit() [1]. In turn both of these feedbacks
are applicable to the other setup loops in this file. So I am thinking
this calls for a follow-on patch to cleanup all the instances of these 2
patterns in this file.

[1]: https://lore.kernel.org/all/Y4ZwXNpwt83puF4W@rric.localdomain/
diff mbox series

Patch

diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c
index c1e395a5b8f7..840ed1a3ba88 100644
--- a/tools/testing/cxl/test/cxl.c
+++ b/tools/testing/cxl/test/cxl.c
@@ -13,9 +13,11 @@ 
 
 #define NR_CXL_HOST_BRIDGES 2
 #define NR_CXL_SINGLE_HOST 1
+#define NR_CXL_RCH 1
 #define NR_CXL_ROOT_PORTS 2
 #define NR_CXL_SWITCH_PORTS 2
 #define NR_CXL_PORT_DECODERS 8
+#define NR_BRIDGES (NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST + NR_CXL_RCH)
 
 static struct platform_device *cxl_acpi;
 static struct platform_device *cxl_host_bridge[NR_CXL_HOST_BRIDGES];
@@ -35,6 +37,8 @@  static struct platform_device *cxl_swd_single[NR_MEM_SINGLE];
 struct platform_device *cxl_mem[NR_MEM_MULTI];
 struct platform_device *cxl_mem_single[NR_MEM_SINGLE];
 
+static struct platform_device *cxl_rch[NR_CXL_RCH];
+static struct platform_device *cxl_rcd[NR_CXL_RCH];
 
 static inline bool is_multi_bridge(struct device *dev)
 {
@@ -57,7 +61,7 @@  static inline bool is_single_bridge(struct device *dev)
 }
 
 static struct acpi_device acpi0017_mock;
-static struct acpi_device host_bridge[NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST] = {
+static struct acpi_device host_bridge[NR_BRIDGES] = {
 	[0] = {
 		.handle = &host_bridge[0],
 	},
@@ -67,7 +71,9 @@  static struct acpi_device host_bridge[NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST]
 	[2] = {
 		.handle = &host_bridge[2],
 	},
-
+	[3] = {
+		.handle = &host_bridge[3],
+	},
 };
 
 static bool is_mock_dev(struct device *dev)
@@ -80,6 +86,9 @@  static bool is_mock_dev(struct device *dev)
 	for (i = 0; i < ARRAY_SIZE(cxl_mem_single); i++)
 		if (dev == &cxl_mem_single[i]->dev)
 			return true;
+	for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++)
+		if (dev == &cxl_rcd[i]->dev)
+			return true;
 	if (dev == &cxl_acpi->dev)
 		return true;
 	return false;
@@ -101,7 +110,7 @@  static bool is_mock_adev(struct acpi_device *adev)
 
 static struct {
 	struct acpi_table_cedt cedt;
-	struct acpi_cedt_chbs chbs[NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST];
+	struct acpi_cedt_chbs chbs[NR_BRIDGES];
 	struct {
 		struct acpi_cedt_cfmws cfmws;
 		u32 target[1];
@@ -122,6 +131,10 @@  static struct {
 		struct acpi_cedt_cfmws cfmws;
 		u32 target[1];
 	} cfmws4;
+	struct {
+		struct acpi_cedt_cfmws cfmws;
+		u32 target[1];
+	} cfmws5;
 } __packed mock_cedt = {
 	.cedt = {
 		.header = {
@@ -154,6 +167,14 @@  static struct {
 		.uid = 2,
 		.cxl_version = ACPI_CEDT_CHBS_VERSION_CXL20,
 	},
+	.chbs[3] = {
+		.header = {
+			.type = ACPI_CEDT_TYPE_CHBS,
+			.length = sizeof(mock_cedt.chbs[0]),
+		},
+		.uid = 3,
+		.cxl_version = ACPI_CEDT_CHBS_VERSION_CXL11,
+	},
 	.cfmws0 = {
 		.cfmws = {
 			.header = {
@@ -229,6 +250,21 @@  static struct {
 		},
 		.target = { 2 },
 	},
+	.cfmws5 = {
+		.cfmws = {
+			.header = {
+				.type = ACPI_CEDT_TYPE_CFMWS,
+				.length = sizeof(mock_cedt.cfmws5),
+			},
+			.interleave_ways = 0,
+			.granularity = 4,
+			.restrictions = ACPI_CEDT_CFMWS_RESTRICT_TYPE3 |
+					ACPI_CEDT_CFMWS_RESTRICT_VOLATILE,
+			.qtg_id = 5,
+			.window_size = SZ_256M,
+		},
+		.target = { 3 },
+	},
 };
 
 struct acpi_cedt_cfmws *mock_cfmws[] = {
@@ -237,6 +273,7 @@  struct acpi_cedt_cfmws *mock_cfmws[] = {
 	[2] = &mock_cedt.cfmws2.cfmws,
 	[3] = &mock_cedt.cfmws3.cfmws,
 	[4] = &mock_cedt.cfmws4.cfmws,
+	[5] = &mock_cedt.cfmws5.cfmws,
 };
 
 struct cxl_mock_res {
@@ -262,11 +299,11 @@  static void depopulate_all_mock_resources(void)
 	mutex_unlock(&mock_res_lock);
 }
 
-static struct cxl_mock_res *alloc_mock_res(resource_size_t size)
+static struct cxl_mock_res *alloc_mock_res(resource_size_t size, int align)
 {
 	struct cxl_mock_res *res = kzalloc(sizeof(*res), GFP_KERNEL);
 	struct genpool_data_align data = {
-		.align = SZ_256M,
+		.align = align,
 	};
 	unsigned long phys;
 
@@ -301,7 +338,7 @@  static int populate_cedt(void)
 		else
 			size = ACPI_CEDT_CHBS_LENGTH_CXL11;
 
-		res = alloc_mock_res(size);
+		res = alloc_mock_res(size, size);
 		if (!res)
 			return -ENOMEM;
 		chbs->base = res->range.start;
@@ -311,7 +348,7 @@  static int populate_cedt(void)
 	for (i = 0; i < ARRAY_SIZE(mock_cfmws); i++) {
 		struct acpi_cedt_cfmws *window = mock_cfmws[i];
 
-		res = alloc_mock_res(window->window_size);
+		res = alloc_mock_res(window->window_size, SZ_256M);
 		if (!res)
 			return -ENOMEM;
 		window->base_hpa = res->range.start;
@@ -372,6 +409,10 @@  static bool is_mock_bridge(struct device *dev)
 	for (i = 0; i < ARRAY_SIZE(cxl_hb_single); i++)
 		if (dev == &cxl_hb_single[i]->dev)
 			return true;
+	for (i = 0; i < ARRAY_SIZE(cxl_rch); i++)
+		if (dev == &cxl_rch[i]->dev)
+			return true;
+
 	return false;
 }
 
@@ -441,7 +482,7 @@  mock_acpi_evaluate_integer(acpi_handle handle, acpi_string pathname,
 	return AE_OK;
 }
 
-static struct pci_bus mock_pci_bus[NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST];
+static struct pci_bus mock_pci_bus[NR_BRIDGES];
 static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
 	[0] = {
 		.bus = &mock_pci_bus[0],
@@ -452,7 +493,9 @@  static struct acpi_pci_root mock_pci_root[ARRAY_SIZE(mock_pci_bus)] = {
 	[2] = {
 		.bus = &mock_pci_bus[2],
 	},
-
+	[3] = {
+		.bus = &mock_pci_bus[3],
+	},
 };
 
 static bool is_mock_bus(struct pci_bus *bus)
@@ -738,6 +781,87 @@  static void mock_companion(struct acpi_device *adev, struct device *dev)
 #define SZ_512G (SZ_64G * 8)
 #endif
 
+static __init int cxl_rch_init(void)
+{
+	int rc, i;
+
+	for (i = 0; i < ARRAY_SIZE(cxl_rch); i++) {
+		int idx = NR_CXL_HOST_BRIDGES + NR_CXL_SINGLE_HOST + i;
+		struct acpi_device *adev = &host_bridge[idx];
+		struct platform_device *pdev;
+
+		pdev = platform_device_alloc("cxl_host_bridge", idx);
+		if (!pdev)
+			goto err_bridge;
+
+		mock_companion(adev, &pdev->dev);
+		rc = platform_device_add(pdev);
+		if (rc) {
+			platform_device_put(pdev);
+			goto err_bridge;
+		}
+
+		cxl_rch[i] = pdev;
+		mock_pci_bus[idx].bridge = &pdev->dev;
+		rc = sysfs_create_link(&pdev->dev.kobj, &pdev->dev.kobj,
+				       "firmware_node");
+		if (rc)
+			goto err_bridge;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(cxl_rcd); i++) {
+		int idx = NR_MEM_MULTI + NR_MEM_SINGLE + i;
+		struct platform_device *rch = cxl_rch[i];
+		struct platform_device *pdev;
+
+		pdev = platform_device_alloc("cxl_rcd", idx);
+		if (!pdev)
+			goto err_mem;
+		pdev->dev.parent = &rch->dev;
+		set_dev_node(&pdev->dev, i % 2);
+
+		rc = platform_device_add(pdev);
+		if (rc) {
+			platform_device_put(pdev);
+			goto err_mem;
+		}
+		cxl_rcd[i] = pdev;
+	}
+
+	return 0;
+
+err_mem:
+	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_rcd[i]);
+err_bridge:
+	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_rch[i];
+
+		if (!pdev)
+			continue;
+		sysfs_remove_link(&pdev->dev.kobj, "firmware_node");
+		platform_device_unregister(cxl_rch[i]);
+	}
+
+	return rc;
+}
+
+static void cxl_rch_exit(void)
+{
+	int i;
+
+	for (i = ARRAY_SIZE(cxl_rcd) - 1; i >= 0; i--)
+		platform_device_unregister(cxl_rcd[i]);
+	for (i = ARRAY_SIZE(cxl_rch) - 1; i >= 0; i--) {
+		struct platform_device *pdev = cxl_rch[i];
+
+		if (!pdev)
+			continue;
+		sysfs_remove_link(&pdev->dev.kobj, "firmware_node");
+		platform_device_unregister(cxl_rch[i]);
+	}
+}
+
 static __init int cxl_single_init(void)
 {
 	int i, rc;
@@ -1010,9 +1134,13 @@  static __init int cxl_test_init(void)
 	if (rc)
 		goto err_mem;
 
+	rc = cxl_rch_init();
+	if (rc)
+		goto err_single;
+
 	cxl_acpi = platform_device_alloc("cxl_acpi", 0);
 	if (!cxl_acpi)
-		goto err_single;
+		goto err_rch;
 
 	mock_companion(&acpi0017_mock, &cxl_acpi->dev);
 	acpi0017_mock.dev.bus = &platform_bus_type;
@@ -1025,6 +1153,8 @@  static __init int cxl_test_init(void)
 
 err_add:
 	platform_device_put(cxl_acpi);
+err_rch:
+	cxl_rch_exit();
 err_single:
 	cxl_single_exit();
 err_mem:
@@ -1062,6 +1192,7 @@  static __exit void cxl_test_exit(void)
 	int i;
 
 	platform_device_unregister(cxl_acpi);
+	cxl_rch_exit();
 	cxl_single_exit();
 	for (i = ARRAY_SIZE(cxl_mem) - 1; i >= 0; i--)
 		platform_device_unregister(cxl_mem[i]);
diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
index a4ee8e61dd60..b59c5976b2d9 100644
--- a/tools/testing/cxl/test/mem.c
+++ b/tools/testing/cxl/test/mem.c
@@ -100,6 +100,24 @@  static int mock_get_log(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
 	return 0;
 }
 
+static int mock_rcd_id(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
+{
+	struct cxl_mbox_identify id = {
+		.fw_revision = { "mock fw v1 " },
+		.total_capacity =
+			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
+		.volatile_capacity =
+			cpu_to_le64(DEV_SIZE / CXL_CAPACITY_MULTIPLIER),
+	};
+
+	if (cmd->size_out < sizeof(id))
+		return -EINVAL;
+
+	memcpy(cmd->payload_out, &id, sizeof(id));
+
+	return 0;
+}
+
 static int mock_id(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *cmd)
 {
 	struct cxl_mbox_identify id = {
@@ -216,7 +234,10 @@  static int cxl_mock_mbox_send(struct cxl_dev_state *cxlds, struct cxl_mbox_cmd *
 		rc = mock_get_log(cxlds, cmd);
 		break;
 	case CXL_MBOX_OP_IDENTIFY:
-		rc = mock_id(cxlds, cmd);
+		if (cxlds->rcd)
+			rc = mock_rcd_id(cxlds, cmd);
+		else
+			rc = mock_id(cxlds, cmd);
 		break;
 	case CXL_MBOX_OP_GET_LSA:
 		rc = mock_get_lsa(cxlds, cmd);
@@ -245,6 +266,13 @@  static void label_area_release(void *lsa)
 	vfree(lsa);
 }
 
+static bool is_rcd(struct platform_device *pdev)
+{
+	const struct platform_device_id *id = platform_get_device_id(pdev);
+
+	return !!id->driver_data;
+}
+
 static int cxl_mock_mem_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -268,6 +296,10 @@  static int cxl_mock_mem_probe(struct platform_device *pdev)
 	cxlds->serial = pdev->id;
 	cxlds->mbox_send = cxl_mock_mbox_send;
 	cxlds->payload_size = SZ_4K;
+	if (is_rcd(pdev)) {
+		cxlds->rcd = true;
+		cxlds->component_reg_phys = CXL_RESOURCE_NONE;
+	}
 
 	rc = cxl_enumerate_cmds(cxlds);
 	if (rc)
@@ -289,7 +321,8 @@  static int cxl_mock_mem_probe(struct platform_device *pdev)
 }
 
 static const struct platform_device_id cxl_mock_mem_ids[] = {
-	{ .name = "cxl_mem", },
+	{ .name = "cxl_mem", 0 },
+	{ .name = "cxl_rcd", 1 },
 	{ },
 };
 MODULE_DEVICE_TABLE(platform, cxl_mock_mem_ids);