From: Klaus Jensen <k.jensen@samsung.com>

Add a 'dbcs' knob to allow Doorbell Buffer Config command to be
disabled.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 hw/nvme/ctrl.c       | 11 ++++++++---
 hw/nvme/nvme.h       |  1 +
 include/block/nvme.h |  2 +-
 3 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 0e95c07c5314fa33674963ef2cea74c78954e86b..d544789f92ffe6b758ce35cecfc025d87efb9b7e 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -278,7 +278,6 @@ static const uint32_t nvme_cse_acs_default[256] = {
     [NVME_ADM_CMD_GET_FEATURES]     = NVME_CMD_EFF_CSUPP,
     [NVME_ADM_CMD_ASYNC_EV_REQ]     = NVME_CMD_EFF_CSUPP,
     [NVME_ADM_CMD_NS_ATTACHMENT]    = NVME_CMD_EFF_CSUPP | NVME_CMD_EFF_NIC,
-    [NVME_ADM_CMD_DBBUF_CONFIG]     = NVME_CMD_EFF_CSUPP,
     [NVME_ADM_CMD_FORMAT_NVM]       = NVME_CMD_EFF_CSUPP | NVME_CMD_EFF_LBCC,
     [NVME_ADM_CMD_DIRECTIVE_RECV]   = NVME_CMD_EFF_CSUPP,
     [NVME_ADM_CMD_DIRECTIVE_SEND]   = NVME_CMD_EFF_CSUPP,
@@ -8709,8 +8708,13 @@ static void nvme_init_ctrl(NvmeCtrl *n, PCIDevice *pci_dev)
     id->mdts = n->params.mdts;
     id->ver = cpu_to_le32(NVME_SPEC_VER);
 
-    oacs = NVME_OACS_NMS | NVME_OACS_FORMAT | NVME_OACS_DBBUF |
-        NVME_OACS_DIRECTIVES;
+    oacs = NVME_OACS_NMS | NVME_OACS_FORMAT | NVME_OACS_DIRECTIVES;
+
+    if (n->params.dbcs) {
+        oacs |= NVME_OACS_DBCS;
+
+        n->cse.acs[NVME_ADM_CMD_DBBUF_CONFIG] = NVME_CMD_EFF_CSUPP;
+    }
 
     if (n->params.sriov_max_vfs) {
         oacs |= NVME_OACS_VMS;
@@ -8960,6 +8964,7 @@ static Property nvme_props[] = {
     DEFINE_PROP_BOOL("use-intel-id", NvmeCtrl, params.use_intel_id, false),
     DEFINE_PROP_BOOL("legacy-cmb", NvmeCtrl, params.legacy_cmb, false),
     DEFINE_PROP_BOOL("ioeventfd", NvmeCtrl, params.ioeventfd, false),
+    DEFINE_PROP_BOOL("dbcs", NvmeCtrl, params.dbcs, true),
     DEFINE_PROP_UINT8("zoned.zasl", NvmeCtrl, params.zasl, 0),
     DEFINE_PROP_BOOL("zoned.auto_transition", NvmeCtrl,
                      params.auto_transition_zones, true),
diff --git a/hw/nvme/nvme.h b/hw/nvme/nvme.h
index 191b6c5398d0c4583051a6a9773c677a49caffd6..cb314e91af32a20f47e0a393e2458b7d4bdd03d9 100644
--- a/hw/nvme/nvme.h
+++ b/hw/nvme/nvme.h
@@ -539,6 +539,7 @@ typedef struct NvmeParams {
     bool     auto_transition_zones;
     bool     legacy_cmb;
     bool     ioeventfd;
+    bool     dbcs;
     uint16_t  sriov_max_vfs;
     uint16_t sriov_vq_flexible;
     uint16_t sriov_vi_flexible;
diff --git a/include/block/nvme.h b/include/block/nvme.h
index 9ebee69369d6bfa6835154a91b2bdaaf7984bf0c..a68a07455d0330b8f7cc283da0a5eadbcc140dab 100644
--- a/include/block/nvme.h
+++ b/include/block/nvme.h
@@ -1195,7 +1195,7 @@ enum NvmeIdCtrlOacs {
     NVME_OACS_NMS           = 1 << 3,
     NVME_OACS_DIRECTIVES    = 1 << 5,
     NVME_OACS_VMS           = 1 << 7,
-    NVME_OACS_DBBUF         = 1 << 8,
+    NVME_OACS_DBCS          = 1 << 8,
 };
 
 enum NvmeIdCtrlOncs {

-- 
2.45.2