Re: [PATCH qemu 10/11] hw/cxl: mailbox-utils: 0x5604 - FMAPI Initiate DC Add

[Fan Ni <nifan.cxl@gmail.com>]

On Wed, Jul 02, 2025 at 05:02:16PM +0100, Jonathan Cameron wrote:
> From: Anisa Su <anisa.su@samsung.com>
> 
> FM DCD Management command 0x5604 implemented per CXL r3.2 Spec Section 7.6.7.6.5
> 
> Signed-off-by: Anisa Su <anisa.su@samsung.com>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Reviewed-by: Fan Ni <fan.ni@samsung.com>

Only a minor comment inline ...
> ---
>  include/hw/cxl/cxl_device.h |   4 ++
>  hw/cxl/cxl-mailbox-utils.c  | 109 ++++++++++++++++++++++++++++++++++++
>  hw/mem/cxl_type3.c          |   8 +--
>  3 files changed, 117 insertions(+), 4 deletions(-)
> 
> diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
> index ed91e5387e..fdee60b977 100644
> --- a/include/hw/cxl/cxl_device.h
> +++ b/include/hw/cxl/cxl_device.h
> @@ -728,4 +728,8 @@ void cxl_create_dc_event_records_for_extents(CXLType3Dev *ct3d,
>                                               CXLDCEventType type,
>                                               CXLDCExtentRaw extents[],
>                                               uint32_t ext_count);
> +bool cxl_extents_overlaps_dpa_range(CXLDCExtentList *list,
> +                                    uint64_t dpa, uint64_t len);
> +bool cxl_extent_groups_overlaps_dpa_range(CXLDCExtentGroupList *list,
> +                                          uint64_t dpa, uint64_t len);
>  #endif
> diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> index d0a1d63582..5ea0d07808 100644
> --- a/hw/cxl/cxl-mailbox-utils.c
> +++ b/hw/cxl/cxl-mailbox-utils.c
> @@ -122,6 +122,7 @@ enum {
>          #define GET_HOST_DC_REGION_CONFIG   0x1
>          #define SET_DC_REGION_CONFIG        0x2
>          #define GET_DC_REGION_EXTENT_LIST   0x3
> +        #define INITIATE_DC_ADD             0x4
>  };
>  
>  /* CCI Message Format CXL r3.1 Figure 7-19 */
> @@ -3542,6 +3543,107 @@ static CXLRetCode cmd_fm_get_dc_region_extent_list(const struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> +/*
> + * Helper function to convert CXLDCExtentRaw to CXLUpdateDCExtentListInPl
> + * in order to reuse cxl_detect_malformed_extent_list() function which accepts
> + * CXLUpdateDCExtentListInPl as a parameter.
> + */
> +static void convert_raw_extents(CXLDCExtentRaw raw_extents[],
> +                                CXLUpdateDCExtentListInPl *extent_list,
> +                                int count)
> +{
> +    int i;
> +
> +    extent_list->num_entries_updated = count;
> +
> +    for (i = 0; i < count; i++) {
> +        extent_list->updated_entries[i].start_dpa = raw_extents[i].start_dpa;
> +        extent_list->updated_entries[i].len = raw_extents[i].len;
> +    }
> +}
> +
> +/* CXL r3.2 Section 7.6.7.6.5 Initiate Dynamic Capacity Add (Opcode 5604h) */

/* CXL r3.2 Section 7.6.7.6.5: Initiate Dynamic Capacity Add (Opcode 5604h) */

Fan

> +static CXLRetCode cmd_fm_initiate_dc_add(const struct cxl_cmd *cmd,
> +                                         uint8_t *payload_in,
> +                                         size_t len_in,
> +                                         uint8_t *payload_out,
> +                                         size_t *len_out,
> +                                         CXLCCI *cci)
> +{
> +    struct {
> +        uint16_t host_id;
> +        uint8_t selection_policy;
> +        uint8_t reg_num;
> +        uint64_t length;
> +        uint8_t tag[0x10];
> +        uint32_t ext_count;
> +        CXLDCExtentRaw extents[];
> +    } QEMU_PACKED *in = (void *)payload_in;
> +    CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
> +    int i, rc;
> +
> +    switch (in->selection_policy) {
> +        case CXL_EXTENT_SELECTION_POLICY_PRESCRIPTIVE: {
> +            /* Adding extents exceeds device's extent tracking ability. */
> +            if (in->ext_count + ct3d->dc.total_extent_count >
> +                CXL_NUM_EXTENTS_SUPPORTED) {
> +                return CXL_MBOX_RESOURCES_EXHAUSTED;
> +            }
> +
> +            g_autofree CXLUpdateDCExtentListInPl *list =
> +                g_malloc0(sizeof(*list) +
> +                    in->ext_count * sizeof(*list->updated_entries));
> +
> +            convert_raw_extents(in->extents, list, in->ext_count);
> +            rc = cxl_detect_malformed_extent_list(ct3d, list);
> +
> +            for (i = 0; i < in->ext_count; i++) {
> +                CXLDCExtentRaw *ext = &in->extents[i];
> +
> +                /* Check requested extents do not overlap with pending ones. */
> +                if (cxl_extent_groups_overlaps_dpa_range(&ct3d->dc.extents_pending,
> +                                                         ext->start_dpa,
> +                                                         ext->len)) {
> +                    return CXL_MBOX_INVALID_EXTENT_LIST;
> +                }
> +                /* Check requested extents do not overlap with existing ones. */
> +                if (cxl_extents_overlaps_dpa_range(&ct3d->dc.extents,
> +                                                   ext->start_dpa,
> +                                                   ext->len)) {
> +                    return CXL_MBOX_INVALID_EXTENT_LIST;
> +                }
> +            }
> +
> +            if (rc) {
> +                return rc;
> +            }
> +
> +            CXLDCExtentGroup *group = NULL;
> +            for (i = 0; i < in->ext_count; i++) {
> +                CXLDCExtentRaw *ext = &in->extents[i];
> +
> +                group = cxl_insert_extent_to_extent_group(group, ext->start_dpa,
> +                                                          ext->len, ext->tag,
> +                                                          ext->shared_seq);
> +            }
> +
> +            cxl_extent_group_list_insert_tail(&ct3d->dc.extents_pending, group);
> +            ct3d->dc.total_extent_count += in->ext_count;
> +            cxl_create_dc_event_records_for_extents(ct3d,
> +                                                    DC_EVENT_ADD_CAPACITY,
> +                                                    in->extents,
> +                                                    in->ext_count);
> +
> +            return CXL_MBOX_SUCCESS;
> +        }
> +        default: {
> +            qemu_log_mask(LOG_UNIMP,
> +                          "CXL extent selection policy not supported.\n");
> +            return CXL_MBOX_INVALID_INPUT;
> +        }
> +    }
> +}
> +
>  static const struct cxl_cmd cxl_cmd_set[256][256] = {
>      [INFOSTAT][BACKGROUND_OPERATION_ABORT] = { "BACKGROUND_OPERATION_ABORT",
>          cmd_infostat_bg_op_abort, 0, 0 },
> @@ -3669,6 +3771,13 @@ static const struct cxl_cmd cxl_cmd_set_fm_dcd[256][256] = {
>           CXL_MBOX_IMMEDIATE_DATA_CHANGE) },
>      [FMAPI_DCD_MGMT][GET_DC_REGION_EXTENT_LIST] = { "GET_DC_REGION_EXTENT_LIST",
>          cmd_fm_get_dc_region_extent_list, 12, 0 },
> +    [FMAPI_DCD_MGMT][INITIATE_DC_ADD] = { "INIT_DC_ADD",
> +        cmd_fm_initiate_dc_add, ~0,
> +        (CXL_MBOX_CONFIG_CHANGE_COLD_RESET |
> +        CXL_MBOX_CONFIG_CHANGE_CONV_RESET |
> +        CXL_MBOX_CONFIG_CHANGE_CXL_RESET |
> +        CXL_MBOX_IMMEDIATE_CONFIG_CHANGE |
> +        CXL_MBOX_IMMEDIATE_DATA_CHANGE) },
>  };
>  
>  /*
> diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
> index 9c2b9d197b..7676d785c2 100644
> --- a/hw/mem/cxl_type3.c
> +++ b/hw/mem/cxl_type3.c
> @@ -1885,8 +1885,8 @@ void qmp_cxl_inject_memory_module_event(const char *path, CxlEventLog log,
>   * the list.
>   * Return value: return true if has overlaps; otherwise, return false
>   */
> -static bool cxl_extents_overlaps_dpa_range(CXLDCExtentList *list,
> -                                           uint64_t dpa, uint64_t len)
> +bool cxl_extents_overlaps_dpa_range(CXLDCExtentList *list,
> +                                    uint64_t dpa, uint64_t len)
>  {
>      CXLDCExtent *ent;
>      Range range1, range2;
> @@ -1931,8 +1931,8 @@ bool cxl_extents_contains_dpa_range(CXLDCExtentList *list,
>      return false;
>  }
>  
> -static bool cxl_extent_groups_overlaps_dpa_range(CXLDCExtentGroupList *list,
> -                                                 uint64_t dpa, uint64_t len)
> +bool cxl_extent_groups_overlaps_dpa_range(CXLDCExtentGroupList *list,
> +                                          uint64_t dpa, uint64_t len)
>  {
>      CXLDCExtentGroup *group;
>  
> -- 
> 2.48.1
> 

-- 
Fan Ni (From gmail)