hw/cxl: mailbox-utils: 0x5600 - FMAPI Get DCD Info

FM DCD Management command 0x5600 implemented per CXL 3.2 Spec Section 7.6.7.6.1.

Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Anisa Su <anisa.su@samsung.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Message-Id: <20250714174509.1984430-3-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

3 files changed, 64 insertions, 0 deletions

diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
index 0b615ea..3304048 100644
--- a/hw/cxl/cxl-mailbox-utils.c
+++ b/hw/cxl/cxl-mailbox-utils.c
@@ -23,6 +23,7 @@
 #include "qemu/uuid.h"
 #include "system/hostmem.h"
 #include "qemu/range.h"
+#include "qapi/qapi-types-cxl.h"
 
 #define CXL_CAPACITY_MULTIPLIER   (256 * MiB)
 #define CXL_DC_EVENT_LOG_SIZE 8
@@ -117,6 +118,8 @@ enum {
         #define GET_PHYSICAL_PORT_STATE     0x1
     TUNNEL = 0x53,
         #define MANAGEMENT_COMMAND     0x0
+    FMAPI_DCD_MGMT = 0x56,
+        #define GET_DCD_INFO    0x0
 };
 
 /* CCI Message Format CXL r3.1 Figure 7-19 */
@@ -3237,6 +3240,52 @@ static CXLRetCode cmd_dcd_release_dyn_cap(const struct cxl_cmd *cmd,
     return CXL_MBOX_SUCCESS;
 }
 
+/* CXL r3.2 section 7.6.7.6.1: Get DCD Info (Opcode 5600h) */
+static CXLRetCode cmd_fm_get_dcd_info(const struct cxl_cmd *cmd,
+                                      uint8_t *payload_in,
+                                      size_t len_in,
+                                      uint8_t *payload_out,
+                                      size_t *len_out,
+                                      CXLCCI *cci)
+{
+    struct {
+        uint8_t num_hosts;
+        uint8_t num_regions_supported;
+        uint8_t rsvd1[2];
+        uint16_t supported_add_sel_policy_bitmask;
+        uint8_t rsvd2[2];
+        uint16_t supported_removal_policy_bitmask;
+        uint8_t sanitize_on_release_bitmask;
+        uint8_t rsvd3;
+        uint64_t total_dynamic_capacity;
+        uint64_t region_blk_size_bitmasks[8];
+    } QEMU_PACKED *out = (void *)payload_out;
+    CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
+    CXLDCRegion *region;
+    int i;
+
+    out->num_hosts = 1;
+    out->num_regions_supported = ct3d->dc.num_regions;
+    stw_le_p(&out->supported_add_sel_policy_bitmask,
+             BIT(CXL_EXTENT_SELECTION_POLICY_PRESCRIPTIVE));
+    stw_le_p(&out->supported_removal_policy_bitmask,
+             BIT(CXL_EXTENT_REMOVAL_POLICY_PRESCRIPTIVE));
+    out->sanitize_on_release_bitmask = 0;
+
+    stq_le_p(&out->total_dynamic_capacity,
+             ct3d->dc.total_capacity / CXL_CAPACITY_MULTIPLIER);
+
+    for (i = 0; i < ct3d->dc.num_regions; i++) {
+        region = &ct3d->dc.regions[i];
+        memcpy(&out->region_blk_size_bitmasks[i],
+               &region->supported_blk_size_bitmask,
+               sizeof(out->region_blk_size_bitmasks[i]));
+    }
+
+    *len_out = sizeof(*out);
+    return CXL_MBOX_SUCCESS;
+}
+
 static const struct cxl_cmd cxl_cmd_set[256][256] = {
     [INFOSTAT][BACKGROUND_OPERATION_ABORT] = { "BACKGROUND_OPERATION_ABORT",
         cmd_infostat_bg_op_abort, 0, 0 },
@@ -3350,6 +3399,11 @@ static const struct cxl_cmd cxl_cmd_set_sw[256][256] = {
                                      cmd_tunnel_management_cmd, ~0, 0 },
 };
 
+static const struct cxl_cmd cxl_cmd_set_fm_dcd[256][256] = {
+    [FMAPI_DCD_MGMT][GET_DCD_INFO] = { "GET_DCD_INFO",
+        cmd_fm_get_dcd_info, 0, 0 },
+};
+
 /*
  * While the command is executing in the background, the device should
  * update the percentage complete in the Background Command Status Register
@@ -3624,7 +3678,12 @@ void cxl_initialize_t3_fm_owned_ld_mctpcci(CXLCCI *cci, DeviceState *d,
                                            DeviceState *intf,
                                            size_t payload_max)
 {
+    CXLType3Dev *ct3d = CXL_TYPE3(d);
+
     cxl_copy_cci_commands(cci, cxl_cmd_set_t3_fm_owned_ld_mctp);
+    if (ct3d->dc.num_regions) {
+        cxl_copy_cci_commands(cci, cxl_cmd_set_fm_dcd);
+    }
     cci->d = d;
     cci->intf = intf;
     cxl_init_cci(cci, payload_max);
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index f283178..d898cfd 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -8,6 +8,7 @@
  *
  * SPDX-License-Identifier: GPL-v2-only
  */
+#include <math.h>
 
 #include "qemu/osdep.h"
 #include "qemu/units.h"
@@ -634,6 +635,8 @@ static bool cxl_create_dc_regions(CXLType3Dev *ct3d, Error **errp)
     uint64_t region_len;
     uint64_t decode_len;
     uint64_t blk_size = 2 * MiB;
+    /* Only 1 block size is supported for now. */
+    uint64_t supported_blk_size_bitmask = blk_size;
     CXLDCRegion *region;
     MemoryRegion *mr;
     uint64_t dc_size;
@@ -679,6 +682,7 @@ static bool cxl_create_dc_regions(CXLType3Dev *ct3d, Error **errp)
             .block_size = blk_size,
             /* dsmad_handle set when creating CDAT table entries */
             .flags = 0,
+            .supported_blk_size_bitmask = supported_blk_size_bitmask,
         };
         ct3d->dc.total_capacity += region->len;
         region->blk_bitmap = bitmap_new(region->len / region->block_size);
diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
index a151e19..7eade9c 100644
--- a/include/hw/cxl/cxl_device.h
+++ b/include/hw/cxl/cxl_device.h
@@ -530,6 +530,7 @@ typedef struct CXLDCRegion {
     uint32_t dsmadhandle;
     uint8_t flags;
     unsigned long *blk_bitmap;
+    uint64_t supported_blk_size_bitmask;
 } CXLDCRegion;
 
 typedef struct CXLSetFeatureInfo {