[v11,07/23] cxl: support dpa initialization without a mailbox

Commit Message

Lucero Palau, Alejandro March 10, 2025, 9:03 p.m. UTC

From: Alejandro Lucero <[e-mail]>

Type3 relies on mailbox CXL_MBOX_OP_IDENTIFY command for initializing
memdev state params which end up being used for dma initialization.

Allow a Type2 driver to initialize dpa simply by giving the size of its
volatile and/or non-volatile hardware partitions.

Export cxl_dpa_setup as well for initializing those added dpa partitions
with the proper resources.

Signed-off-by: Alejandro Lucero <[e-mail]>
---
 drivers/cxl/core/mbox.c | 18 +++++++++++++++---
 drivers/cxl/cxlmem.h    | 13 -------------
 include/cxl/cxl.h       | 14 ++++++++++++++
 3 files changed, 29 insertions(+), 16 deletions(-)

Comments

Ben Cheatham March 11, 2025, 8:05 p.m. UTC | #1

On 3/10/25 4:03 PM, [e-mail] wrote:
> From: Alejandro Lucero <[e-mail]>
> 
> Type3 relies on mailbox CXL_MBOX_OP_IDENTIFY command for initializing
> memdev state params which end up being used for dma initialization.
> 
> Allow a Type2 driver to initialize dpa simply by giving the size of its
> volatile and/or non-volatile hardware partitions.
> 
> Export cxl_dpa_setup as well for initializing those added dpa partitions
> with the proper resources.
> 
> Signed-off-by: Alejandro Lucero <[e-mail]>
> ---

Reviewed-by: Ben Cheatham <[e-mail]>

Patch

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 20df6f78f148..8128f48e96d4 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -5,6 +5,7 @@ 
 #include <linux/ktime.h>
 #include <linux/mutex.h>
 #include <linux/unaligned.h>
+#include <cxl/cxl.h>
 #include <cxlpci.h>
 #include <cxlmem.h>
 #include <cxl.h>
@@ -1284,6 +1285,18 @@  static void add_part(struct cxl_dpa_info *info, u64 start, u64 size, enum cxl_pa
 	info->nr_partitions++;
 }
 
+void cxl_mem_dpa_init(struct cxl_dpa_info *info, u64 volatile_bytes,
+		      u64 persistent_bytes)
+{
+	if (!info->size)
+		info->size = volatile_bytes + persistent_bytes;
+
+	add_part(info, 0, volatile_bytes, CXL_PARTMODE_RAM);
+	add_part(info, volatile_bytes, persistent_bytes,
+		 CXL_PARTMODE_PMEM);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_mem_dpa_init, "CXL");
+
 int cxl_mem_dpa_fetch(struct cxl_memdev_state *mds, struct cxl_dpa_info *info)
 {
 	struct cxl_dev_state *cxlds = &mds->cxlds;
@@ -1298,9 +1311,8 @@  int cxl_mem_dpa_fetch(struct cxl_memdev_state *mds, struct cxl_dpa_info *info)
 	info->size = mds->total_bytes;
 
 	if (mds->partition_align_bytes == 0) {
-		add_part(info, 0, mds->volatile_only_bytes, CXL_PARTMODE_RAM);
-		add_part(info, mds->volatile_only_bytes,
-			 mds->persistent_only_bytes, CXL_PARTMODE_PMEM);
+		cxl_mem_dpa_init(info, mds->volatile_only_bytes,
+				 mds->persistent_only_bytes);
 		return 0;
 	}
 
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index e7cd31b9f107..e47f51025efd 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -98,19 +98,6 @@  int devm_cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled,
 			 resource_size_t base, resource_size_t len,
 			 resource_size_t skipped);
 
-#define CXL_NR_PARTITIONS_MAX 2
-
-struct cxl_dpa_info {
-	u64 size;
-	struct cxl_dpa_part_info {
-		struct range range;
-		enum cxl_partition_mode mode;
-	} part[CXL_NR_PARTITIONS_MAX];
-	int nr_partitions;
-};
-
-int cxl_dpa_setup(struct cxl_dev_state *cxlds, const struct cxl_dpa_info *info);
-
 static inline struct cxl_ep *cxl_ep_load(struct cxl_port *port,
 					 struct cxl_memdev *cxlmd)
 {
diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
index 1b452b0c2908..af7d3c4d8142 100644
--- a/include/cxl/cxl.h
+++ b/include/cxl/cxl.h
@@ -210,6 +210,17 @@  struct cxl_dev_state {
 #endif
 };
 
+#define CXL_NR_PARTITIONS_MAX 2
+
+struct cxl_dpa_info {
+	u64 size;
+	struct cxl_dpa_part_info {
+		struct range range;
+		enum cxl_partition_mode mode;
+	} part[CXL_NR_PARTITIONS_MAX];
+	int nr_partitions;
+};
+
 struct cxl_dev_state *_cxl_dev_state_create(struct device *dev,
 					    enum cxl_devtype type, u64 serial,
 					    u16 dvsec, size_t size,
@@ -228,4 +239,7 @@  struct pci_dev;
 struct cxl_memdev_state;
 int cxl_pci_accel_setup_regs(struct pci_dev *pdev, struct cxl_dev_state *cxlmds,
 			     unsigned long *caps);
+void cxl_mem_dpa_init(struct cxl_dpa_info *info, u64 volatile_bytes,
+		      u64 persistent_bytes);
+int cxl_dpa_setup(struct cxl_dev_state *cxlds, const struct cxl_dpa_info *info);
 #endif