Re: [PATCH v2 1/3] hw/cxl/cxl-mailbox-utils: Add support for feature commands (8.2.9.6)

[fan <nifan.cxl@gmail.com>]

On Fri, Nov 24, 2023 at 09:53:35PM +0800, shiju.jose@huawei.com wrote:
> From: Shiju Jose <shiju.jose@huawei.com>
> 
> CXL spec 3.0 section 8.2.9.6 describes optional device specific features.
> CXL devices supports features with changeable attributes.
> Get Supported Features retrieves the list of supported device specific
> features. The settings of a feature can be retrieved using Get Feature and
> optionally modified using Set Feature.
> 
> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
> ---

Updated the references to align with cxl spec r3.1, other than that looks
good to me.

Fan

>  hw/cxl/cxl-mailbox-utils.c | 167 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 167 insertions(+)
> 
> diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> index 6184f44339..1bbc9a48a6 100644
> --- a/hw/cxl/cxl-mailbox-utils.c
> +++ b/hw/cxl/cxl-mailbox-utils.c
> @@ -66,6 +66,10 @@ enum {
>      LOGS        = 0x04,
>          #define GET_SUPPORTED 0x0
>          #define GET_LOG       0x1
> +    FEATURES    = 0x05,
> +        #define GET_SUPPORTED 0x0
> +        #define GET_FEATURE   0x1
> +        #define SET_FEATURE   0x2
>      IDENTIFY    = 0x40,
>          #define MEMORY_DEVICE 0x0
>      CCLS        = 0x41,
> @@ -785,6 +789,157 @@ static CXLRetCode cmd_logs_get_log(const struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> +/* CXL r3.0 section 8.2.9.6: Features */
> +typedef struct CXLSupportedFeatureHeader {
> +    uint16_t entries;
> +    uint16_t nsuppfeats_dev;
> +    uint32_t reserved;
> +} QEMU_PACKED CXLSupportedFeatureHeader;
> +
> +typedef struct CXLSupportedFeatureEntry {
> +    QemuUUID uuid;
> +    uint16_t feat_index;
> +    uint16_t get_feat_size;
> +    uint16_t set_feat_size;
> +    uint32_t attrb_flags;
> +    uint8_t get_feat_version;
> +    uint8_t set_feat_version;
> +    uint16_t set_feat_effects;
> +    uint8_t rsvd[18];
> +} QEMU_PACKED CXLSupportedFeatureEntry;
> +
> +enum CXL_SUPPORTED_FEATURES_LIST {
> +    CXL_FEATURE_MAX
> +};
> +
> +/* Get Feature CXL 3.0 Spec 8.2.9.6.2 */
> +/*
> + * Get Feature input payload
> + * CXL rev 3.0 section 8.2.9.6.2; Table 8-79
> + */
> +/* Get Feature : Payload in selection */
> +enum CXL_GET_FEATURE_SELECTION {
> +    CXL_GET_FEATURE_SEL_CURRENT_VALUE = 0x0,
> +    CXL_GET_FEATURE_SEL_DEFAULT_VALUE = 0x1,
> +    CXL_GET_FEATURE_SEL_SAVED_VALUE = 0x2,
> +    CXL_GET_FEATURE_SEL_MAX
> +};
> +
> +/* Set Feature CXL 3.0 Spec 8.2.9.6.3 */
> +/*
> + * Set Feature input payload
> + * CXL rev 3.0 section 8.2.9.6.3; Table 8-81
> + */
> +typedef struct CXLSetFeatureInHeader {
> +        QemuUUID uuid;
> +        uint32_t flags;
> +        uint16_t offset;
> +        uint8_t version;
> +        uint8_t rsvd[9];
> +} QEMU_PACKED QEMU_ALIGNED(16) CXLSetFeatureInHeader;
> +
> +/* Set Feature : Payload in flags */
> +#define CXL_SET_FEATURE_FLAG_DATA_TRANSFER_MASK   0x7
> +enum CXL_SET_FEATURE_FLAG_DATA_TRANSFER {
> +    CXL_SET_FEATURE_FLAG_FULL_DATA_TRANSFER = 0x0,
> +    CXL_SET_FEATURE_FLAG_INITIATE_DATA_TRANSFER = 0x1,
> +    CXL_SET_FEATURE_FLAG_CONTINUE_DATA_TRANSFER = 0x2,
> +    CXL_SET_FEATURE_FLAG_FINISH_DATA_TRANSFER = 0x3,
> +    CXL_SET_FEATURE_FLAG_ABORT_DATA_TRANSFER = 0x4,
> +    CXL_SET_FEATURE_FLAG_DATA_TRANSFER_MAX
> +};
> +
> +/* CXL r3.0 section 8.2.9.6.1: Get Supported Features (Opcode 0500h) */
> +static CXLRetCode cmd_features_get_supported(const struct cxl_cmd *cmd,
> +                                             uint8_t *payload_in,
> +                                             size_t len_in,
> +                                             uint8_t *payload_out,
> +                                             size_t *len_out,
> +                                             CXLCCI *cci)
> +{
> +    struct {
> +        uint32_t count;
> +        uint16_t start_index;
> +        uint16_t reserved;
> +    } QEMU_PACKED QEMU_ALIGNED(16) * get_feats_in = (void *)payload_in;
> +
> +    struct {
> +        CXLSupportedFeatureHeader hdr;
> +        CXLSupportedFeatureEntry feat_entries[];
> +    } QEMU_PACKED QEMU_ALIGNED(16) * get_feats_out = (void *)payload_out;
> +    uint16_t index;
> +    uint16_t entry, req_entries;
> +    uint16_t feat_entries = 0;
> +
> +    if (get_feats_in->count < sizeof(CXLSupportedFeatureHeader) ||
> +        get_feats_in->start_index > CXL_FEATURE_MAX) {
> +        return CXL_MBOX_INVALID_INPUT;
> +    }
> +    req_entries = (get_feats_in->count -
> +                   sizeof(CXLSupportedFeatureHeader)) /
> +                   sizeof(CXLSupportedFeatureEntry);
> +    req_entries = MIN(req_entries, CXL_FEATURE_MAX);
> +    index = get_feats_in->start_index;
> +
> +    entry = 0;
> +    while (entry < req_entries) {
> +        switch (index) {
> +        default:
> +            break;
> +        }
> +        index++;
> +        entry++;
> +    }
> +
> +    get_feats_out->hdr.nsuppfeats_dev = CXL_FEATURE_MAX;
> +    get_feats_out->hdr.entries = feat_entries;
> +    *len_out = sizeof(CXLSupportedFeatureHeader) +
> +                      feat_entries * sizeof(CXLSupportedFeatureEntry);
> +
> +    return CXL_MBOX_SUCCESS;
> +}
> +
> +/* CXL r3.0 section 8.2.9.6.2: Get Feature (Opcode 0501h) */
> +static CXLRetCode cmd_features_get_feature(const struct cxl_cmd *cmd,
> +                                           uint8_t *payload_in,
> +                                           size_t len_in,
> +                                           uint8_t *payload_out,
> +                                           size_t *len_out,
> +                                           CXLCCI *cci)
> +{
> +    struct {
> +        QemuUUID uuid;
> +        uint16_t offset;
> +        uint16_t count;
> +        uint8_t selection;
> +    } QEMU_PACKED QEMU_ALIGNED(16) * get_feature;
> +    uint16_t bytes_to_copy = 0;
> +
> +    get_feature = (void *)payload_in;
> +
> +    if (get_feature->selection != CXL_GET_FEATURE_SEL_CURRENT_VALUE) {
> +        return CXL_MBOX_UNSUPPORTED;
> +    }
> +    if (get_feature->offset + get_feature->count > cci->payload_max) {
> +        return CXL_MBOX_INVALID_INPUT;
> +    }
> +
> +    *len_out = bytes_to_copy;
> +
> +    return CXL_MBOX_SUCCESS;
> +}
> +
> +/* CXL r3.0 section 8.2.9.6.3: Set Feature (Opcode 0502h) */
> +static CXLRetCode cmd_features_set_feature(const struct cxl_cmd *cmd,
> +                                           uint8_t *payload_in,
> +                                           size_t len_in,
> +                                           uint8_t *payload_out,
> +                                           size_t *len_out,
> +                                           CXLCCI *cci)
> +{
> +    return CXL_MBOX_SUCCESS;
> +}
> +
>  /* 8.2.9.5.1.1 */
>  static CXLRetCode cmd_identify_memory_device(const struct cxl_cmd *cmd,
>                                               uint8_t *payload_in,
> @@ -1954,6 +2109,18 @@ static const struct cxl_cmd cxl_cmd_set[256][256] = {
>      [LOGS][GET_SUPPORTED] = { "LOGS_GET_SUPPORTED", cmd_logs_get_supported,
>                                0, 0 },
>      [LOGS][GET_LOG] = { "LOGS_GET_LOG", cmd_logs_get_log, 0x18, 0 },
> +    [FEATURES][GET_SUPPORTED] = { "FEATURES_GET_SUPPORTED",
> +                                  cmd_features_get_supported, 0x8, 0 },
> +    [FEATURES][GET_FEATURE] = { "FEATURES_GET_FEATURE",
> +                                cmd_features_get_feature, 0x15, 0 },
> +    [FEATURES][SET_FEATURE] = { "FEATURES_SET_FEATURE",
> +                                cmd_features_set_feature,
> +                                ~0,
> +                                (CXL_MBOX_IMMEDIATE_CONFIG_CHANGE |
> +                                 CXL_MBOX_IMMEDIATE_DATA_CHANGE |
> +                                 CXL_MBOX_IMMEDIATE_POLICY_CHANGE |
> +                                 CXL_MBOX_IMMEDIATE_LOG_CHANGE |
> +                                 CXL_MBOX_SECURITY_STATE_CHANGE)},
>      [IDENTIFY][MEMORY_DEVICE] = { "IDENTIFY_MEMORY_DEVICE",
>          cmd_identify_memory_device, 0, 0 },
>      [CCLS][GET_PARTITION_INFO] = { "CCLS_GET_PARTITION_INFO",
> -- 
> 2.34.1
>