On Wed, May 27, 2026 at 02:34:31PM -0700, Dave Jiang wrote: > > > On 5/23/26 2:42 AM, Anisa Su wrote: > > From: Ira Weiny <[email protected]> > > > > Per the CXL 3.1 specification software must check the Command Effects > > May as well update to CXL r4.0 > Updated! > > Log (CEL) for dynamic capacity command support. > > > > Detect support for the DCD commands while reading the CEL, including: > > > > Get DC Config > > Get DC Extent List > > Add DC Response > > Release DC > > > > Based on an original patch by Navneet Singh. > > > > Signed-off-by: Ira Weiny <[email protected]> > > missing Anisa sign off > Added! > > > > --- > > Changes: > > [anisa: rebase] > > --- > > drivers/cxl/core/mbox.c | 43 +++++++++++++++++++++++++++++++++++++++++ > > drivers/cxl/cxlmem.h | 15 ++++++++++++++ > > 2 files changed, 58 insertions(+) > > > > diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c > > index aaa5c6277ebf..7ef5708bf210 100644 > > --- a/drivers/cxl/core/mbox.c > > +++ b/drivers/cxl/core/mbox.c > > @@ -165,6 +165,42 @@ static void cxl_set_security_cmd_enabled(struct > > cxl_security_state *security, > > } > > } > > > > +static bool cxl_is_dcd_command(u16 opcode) > > +{ > > +#define CXL_MBOX_OP_DCD_CMDS 0x48 > > + > > + return (opcode >> 8) == CXL_MBOX_OP_DCD_CMDS; > > +} > > + > > +static void cxl_set_dcd_cmd_enabled(struct cxl_memdev_state *mds, u16 > > opcode, > > + unsigned long *cmd_mask) > > mds not used, consider drop > dropped > > +{ > > + switch (opcode) { > > + case CXL_MBOX_OP_GET_DC_CONFIG: > > + set_bit(CXL_DCD_ENABLED_GET_CONFIG, cmd_mask); > > + break; > > + case CXL_MBOX_OP_GET_DC_EXTENT_LIST: > > + set_bit(CXL_DCD_ENABLED_GET_EXTENT_LIST, cmd_mask); > > + break; > > + case CXL_MBOX_OP_ADD_DC_RESPONSE: > > + set_bit(CXL_DCD_ENABLED_ADD_RESPONSE, cmd_mask); > > + break; > > + case CXL_MBOX_OP_RELEASE_DC: > > + set_bit(CXL_DCD_ENABLED_RELEASE, cmd_mask); > > + break; > > + default: > > + break; > > + } > > +} > > + > > +static bool cxl_verify_dcd_cmds(struct cxl_memdev_state *mds, unsigned > > long *cmds_seen) > > mds not used. consider drop > also dropped > > +{ > > + DECLARE_BITMAP(all_cmds, CXL_DCD_ENABLED_MAX); > > + > > + bitmap_fill(all_cmds, CXL_DCD_ENABLED_MAX); > > + return bitmap_equal(cmds_seen, all_cmds, CXL_DCD_ENABLED_MAX); > > Above lines can be replaced with: > return bitmap_full(cmds_seen, CXL_DCD_ENABLED_MAX); > replaced > > +} > > + > > static bool cxl_is_poison_command(u16 opcode) > > { > > #define CXL_MBOX_OP_POISON_CMDS 0x43 > > @@ -757,6 +793,7 @@ static void cxl_walk_cel(struct cxl_memdev_state *mds, > > size_t size, u8 *cel) > > struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox; > > struct cxl_cel_entry *cel_entry; > > const int cel_entries = size / sizeof(*cel_entry); > > + DECLARE_BITMAP(dcd_cmds, CXL_DCD_ENABLED_MAX); > > Need to zero out the declared bitmap 'dcd_cmds' on stack before using. > > DECLARE_BITMAP(dcd_cmds, CXL_DCD_ENABLED_MAX) = {}; > done :) > > struct device *dev = mds->cxlds.dev; > > int i, ro_cmds = 0, wr_cmds = 0; > > > > @@ -785,11 +822,17 @@ static void cxl_walk_cel(struct cxl_memdev_state > > *mds, size_t size, u8 *cel) > > enabled++; > > } > > > > + if (cxl_is_dcd_command(opcode)) { > > + cxl_set_dcd_cmd_enabled(mds, opcode, dcd_cmds); > > + enabled++; > > + } > > + > > dev_dbg(dev, "Opcode 0x%04x %s\n", opcode, > > enabled ? "enabled" : "unsupported by driver"); > > } > > > > set_features_cap(cxl_mbox, ro_cmds, wr_cmds); > > + mds->dcd_supported = cxl_verify_dcd_cmds(mds, dcd_cmds); > > } > > > > static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct > > cxl_memdev_state *mds) > > diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h > > index 776c50d1db51..53444af448d7 100644 > > --- a/drivers/cxl/cxlmem.h > > +++ b/drivers/cxl/cxlmem.h > > @@ -230,6 +230,15 @@ struct cxl_event_state { > > struct mutex log_lock; > > }; > > > > +/* Device enabled DCD commands */ > > +enum dcd_cmd_enabled_bits { > > + CXL_DCD_ENABLED_GET_CONFIG, > > + CXL_DCD_ENABLED_GET_EXTENT_LIST, > > + CXL_DCD_ENABLED_ADD_RESPONSE, > > + CXL_DCD_ENABLED_RELEASE, > > + CXL_DCD_ENABLED_MAX > > +}; > > + > > would be nice to have comment point to where in the spec this is > Added > DJ > Thanks! Anisa > > /* Device enabled poison commands */ > > enum poison_cmd_enabled_bits { > > CXL_POISON_ENABLED_LIST, > > @@ -405,6 +414,7 @@ static inline struct cxl_dev_state > > *mbox_to_cxlds(struct cxl_mailbox *cxl_mbox) > > * @partition_align_bytes: alignment size for partition-able capacity > > * @active_volatile_bytes: sum of hard + soft volatile > > * @active_persistent_bytes: sum of hard + soft persistent > > + * @dcd_supported: all DCD commands are supported > > * @event: event log driver state > > * @poison: poison driver state info > > * @security: security driver state info > > @@ -424,6 +434,7 @@ struct cxl_memdev_state { > > u64 partition_align_bytes; > > u64 active_volatile_bytes; > > u64 active_persistent_bytes; > > + bool dcd_supported; > > > > struct cxl_event_state event; > > struct cxl_poison_state poison; > > @@ -485,6 +496,10 @@ enum cxl_opcode { > > CXL_MBOX_OP_UNLOCK = 0x4503, > > CXL_MBOX_OP_FREEZE_SECURITY = 0x4504, > > CXL_MBOX_OP_PASSPHRASE_SECURE_ERASE = 0x4505, > > + CXL_MBOX_OP_GET_DC_CONFIG = 0x4800, > > + CXL_MBOX_OP_GET_DC_EXTENT_LIST = 0x4801, > > + CXL_MBOX_OP_ADD_DC_RESPONSE = 0x4802, > > + CXL_MBOX_OP_RELEASE_DC = 0x4803, > > CXL_MBOX_OP_MAX = 0x10000 > > }; > > >

