[PATCH v11 06/14] cxl/mbox: Add SET_FEATURE mailbox command

shiju.jose
2024-08-16T16:43:40Z

Add support for SET_FEATURE mailbox command.

CXL spec 3.1 section 8.2.9.6 describes optional device specific features.
CXL devices supports features with changeable attributes.
The settings of a feature can be optionally modified using Set Feature
command.
CXL spec 3.1 section 8.2.9.6.3 describes Set Feature command.

Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
---
drivers/cxl/core/mbox.c | 72 +++++++++++++++++++++++++++++++++++++++++
drivers/cxl/cxlmem.h | 34 +++++++++++++++++++
2 files changed, 106 insertions(+)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index c283684e8e73..f79269add159 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -1432,6 +1432,78 @@ size_t cxl_get_feature(struct cxl_memdev_state *mds,
}
EXPORT_SYMBOL_NS_GPL(cxl_get_feature, CXL);

+/*
+ * FEAT_DATA_MIN_PAYLOAD_SIZE - min extra number of bytes should be
+ * available in the mailbox for storing the actual feature data so that
+ * the feature data transfer would work as expected.
+ */
+#define FEAT_DATA_MIN_PAYLOAD_SIZE 10
+int cxl_set_feature(struct cxl_memdev_state *mds,
+ const uuid_t feat_uuid, u8 feat_version,
+ void *feat_data, size_t feat_data_size,
+ u8 feat_flag)
+{
+ struct cxl_memdev_set_feat_pi {
+ struct cxl_mbox_set_feat_hdr hdr;
+ u8 feat_data[];
+ } __packed;
+ size_t data_in_size, data_sent_size = 0;
+ struct cxl_mbox_cmd mbox_cmd;
+ size_t hdr_size;
+ int rc = 0;
+
+ struct cxl_memdev_set_feat_pi *pi __free(kfree) =
+ kmalloc(mds->payload_size, GFP_KERNEL);
+ pi->hdr.uuid = feat_uuid;
+ pi->hdr.version = feat_version;
+ feat_flag &= ~CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK;
+ feat_flag |= CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET;
+ hdr_size = sizeof(pi->hdr);
+ /*
+ * Check minimum mbox payload size is available for
+ * the feature data transfer.
+ */
+ if (hdr_size + FEAT_DATA_MIN_PAYLOAD_SIZE > mds->payload_size)
+ return -ENOMEM;
+
+ if ((hdr_size + feat_data_size) <= mds->payload_size) {
+ pi->hdr.flags = cpu_to_le32(feat_flag |
+ CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER);
+ data_in_size = feat_data_size;
+ } else {
+ pi->hdr.flags = cpu_to_le32(feat_flag |
+ CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER);
+ data_in_size = mds->payload_size - hdr_size;
+ }
+
+ do {
+ pi->hdr.offset = cpu_to_le16(data_sent_size);
+ memcpy(pi->feat_data, feat_data + data_sent_size, data_in_size);
+ mbox_cmd = (struct cxl_mbox_cmd) {
+ .opcode = CXL_MBOX_OP_SET_FEATURE,
+ .size_in = hdr_size + data_in_size,
+ .payload_in = pi,
+ };
+ rc = cxl_internal_send_cmd(mds, &mbox_cmd);
+ if (rc < 0)
+ return rc;
+
+ data_sent_size += data_in_size;
+ if (data_sent_size >= feat_data_size)
+ return 0;
+
+ if ((feat_data_size - data_sent_size) <= (mds->payload_size - hdr_size)) {
+ data_in_size = feat_data_size - data_sent_size;
+ pi->hdr.flags = cpu_to_le32(feat_flag |
+ CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER);
+ } else {
+ pi->hdr.flags = cpu_to_le32(feat_flag |
+ CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER);
+ }
+ } while (true);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_set_feature, CXL);
+
int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
struct cxl_region *cxlr)
{
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 608e3ed845a7..a092a14361ec 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -533,6 +533,7 @@ enum cxl_opcode {
CXL_MBOX_OP_GET_SUP_LOG_SUBLIST = 0x0405,
CXL_MBOX_OP_GET_SUPPORTED_FEATURES = 0x0500,
CXL_MBOX_OP_GET_FEATURE = 0x0501,
+ CXL_MBOX_OP_SET_FEATURE = 0x0502,
CXL_MBOX_OP_IDENTIFY = 0x4000,
CXL_MBOX_OP_GET_PARTITION_INFO = 0x4100,
CXL_MBOX_OP_SET_PARTITION_INFO = 0x4101,
@@ -781,6 +782,35 @@ struct cxl_mbox_get_feat_in {
u8 selection;
} __packed;

+/*
+ * Set Feature CXL 3.1 Spec 8.2.9.6.3
+ */
+
+/*
+ * Set Feature input payload
+ * CXL rev 3.1 section 8.2.9.6.3 Table 8-101
+ */
+/* Set Feature : Payload in flags */
+#define CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK GENMASK(2, 0)
+enum cxl_set_feat_flag_data_transfer {
+ CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER,
+ CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER,
+ CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER,
+ CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER,
+ CXL_SET_FEAT_FLAG_ABORT_DATA_TRANSFER,
+ CXL_SET_FEAT_FLAG_DATA_TRANSFER_MAX
+};
+
+#define CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET BIT(3)
+
+struct cxl_mbox_set_feat_hdr {
+ uuid_t uuid;
+ __le32 flags;
+ __le16 offset;
+ u8 version;
+ u8 rsvd[9];
+} __packed;
+
/* Get Poison List CXL 3.0 Spec 8.2.9.8.4.1 */
struct cxl_mbox_poison_in {
__le64 offset;
@@ -921,6 +951,10 @@ size_t cxl_get_feature(struct cxl_memdev_state *mds,
const uuid_t feat_uuid,
enum cxl_get_feat_selection selection,
void *feat_out, size_t feat_out_size);
+int cxl_set_feature(struct cxl_memdev_state *mds,
+ const uuid_t feat_uuid, u8 feat_version,
+ void *feat_data, size_t feat_data_size,
+ u8 feat_flag);
int cxl_poison_state_init(struct cxl_memdev_state *mds);
int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
struct cxl_region *cxlr);
--
2.34.1