Re: [PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-03-04 Thread fan
On Mon, Mar 04, 2024 at 12:40:18PM +, Jørgen Hansen wrote:
> On 2/21/24 19:15, nifan@gmail.com wrote:
> > CAUTION: This email originated from outside of Western Digital. Do not 
> > click on links or open attachments unless you recognize the sender and know 
> > that the content is safe.
> > 
> > 
> > From: Fan Ni 
> > 
> > Per cxl spec r3.1, add dynamic capacity region representative based on
> > Table 8-165 and extend the cxl type3 device definition to include dc region
> > information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
> > Configuration' mailbox support.
> > 
> > Note: decode_len of a dc region is aligned to 256*MiB, divided by
> > 256 * MiB before returned to the host for "Get Dynamic Capacity 
> > Configuration"
> > mailbox command.
> > 
> > Signed-off-by: Fan Ni 
> > ---
> >   hw/cxl/cxl-mailbox-utils.c  | 110 
> >   include/hw/cxl/cxl_device.h |  16 ++
> >   2 files changed, 126 insertions(+)
> > 
> 
> [snip]
> 
> > 
> >   /* No separation for PCI MB as protocol handled in PCI device */
> > diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
> > index 3cf3077afa..6df7fecdf1 100644
> > --- a/include/hw/cxl/cxl_device.h
> > +++ b/include/hw/cxl/cxl_device.h
> > @@ -422,6 +422,17 @@ typedef struct CXLPoison {
> >   typedef QLIST_HEAD(, CXLPoison) CXLPoisonList;
> >   #define CXL_POISON_LIST_LIMIT 256
> > 
> > +#define DCD_MAX_REGION_NUM 8
> > +
> > +typedef struct CXLDCDRegion {
> > +uint64_t base;
> > +uint64_t decode_len; /* aligned to 256*MiB */
> > +uint64_t len;
> > +uint64_t block_size;
> > +uint32_t dsmadhandle;
> > +uint8_t flags;
> > +} CXLDCDRegion;
> > +
> 
> To be consistent with the naming of extents, and functions defined later 
> on, shouldn't this be CXLDCRegion (DC instead of DCD)?
> 

I was also thinking about it and a bit lazy to make the change until
someone points out. Now I have a good reason to make the change :-).
Thanks.

Fan

> >   struct CXLType3Dev {
> >   /* Private */
> >   PCIDevice parent_obj;
> > @@ -454,6 +465,11 @@ struct CXLType3Dev {
> >   unsigned int poison_list_cnt;
> >   bool poison_list_overflowed;
> >   uint64_t poison_list_overflow_ts;
> > +
> > +struct dynamic_capacity {
> > +uint8_t num_regions; /* 0-8 regions */
> > +CXLDCDRegion regions[DCD_MAX_REGION_NUM];
> > +} dc;
> >   };
> > 
> >   #define TYPE_CXL_TYPE3 "cxl-type3"
> > --
> > 2.43.0
> > 
> > 
> 
> Thanks,
> Jorgen



Re: [PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-03-04 Thread Jørgen Hansen
On 2/21/24 19:15, nifan@gmail.com wrote:
> CAUTION: This email originated from outside of Western Digital. Do not click 
> on links or open attachments unless you recognize the sender and know that 
> the content is safe.
> 
> 
> From: Fan Ni 
> 
> Per cxl spec r3.1, add dynamic capacity region representative based on
> Table 8-165 and extend the cxl type3 device definition to include dc region
> information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
> Configuration' mailbox support.
> 
> Note: decode_len of a dc region is aligned to 256*MiB, divided by
> 256 * MiB before returned to the host for "Get Dynamic Capacity Configuration"
> mailbox command.
> 
> Signed-off-by: Fan Ni 
> ---
>   hw/cxl/cxl-mailbox-utils.c  | 110 
>   include/hw/cxl/cxl_device.h |  16 ++
>   2 files changed, 126 insertions(+)
> 

[snip]

> 
>   /* No separation for PCI MB as protocol handled in PCI device */
> diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
> index 3cf3077afa..6df7fecdf1 100644
> --- a/include/hw/cxl/cxl_device.h
> +++ b/include/hw/cxl/cxl_device.h
> @@ -422,6 +422,17 @@ typedef struct CXLPoison {
>   typedef QLIST_HEAD(, CXLPoison) CXLPoisonList;
>   #define CXL_POISON_LIST_LIMIT 256
> 
> +#define DCD_MAX_REGION_NUM 8
> +
> +typedef struct CXLDCDRegion {
> +uint64_t base;
> +uint64_t decode_len; /* aligned to 256*MiB */
> +uint64_t len;
> +uint64_t block_size;
> +uint32_t dsmadhandle;
> +uint8_t flags;
> +} CXLDCDRegion;
> +

To be consistent with the naming of extents, and functions defined later 
on, shouldn't this be CXLDCRegion (DC instead of DCD)?

>   struct CXLType3Dev {
>   /* Private */
>   PCIDevice parent_obj;
> @@ -454,6 +465,11 @@ struct CXLType3Dev {
>   unsigned int poison_list_cnt;
>   bool poison_list_overflowed;
>   uint64_t poison_list_overflow_ts;
> +
> +struct dynamic_capacity {
> +uint8_t num_regions; /* 0-8 regions */
> +CXLDCDRegion regions[DCD_MAX_REGION_NUM];
> +} dc;
>   };
> 
>   #define TYPE_CXL_TYPE3 "cxl-type3"
> --
> 2.43.0
> 
> 

Thanks,
Jorgen

Re: [PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-02-26 Thread fan
On Mon, Feb 26, 2024 at 05:33:17PM +, Jonathan Cameron wrote:
> On Wed, 21 Feb 2024 10:15:55 -0800
> nifan@gmail.com wrote:
> 
> > From: Fan Ni 
> > 
> > Per cxl spec r3.1, add dynamic capacity region representative based on
> > Table 8-165 and extend the cxl type3 device definition to include dc region
> > information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
> > Configuration' mailbox support.
> > 
> > Note: decode_len of a dc region is aligned to 256*MiB, divided by
> > 256 * MiB before returned to the host for "Get Dynamic Capacity 
> > Configuration"
> > mailbox command.
> > 
> > Signed-off-by: Fan Ni 
> Hi Fan,
> 
> A few comments inline.
> 
> Jonathan
> 
> > ---
> >  hw/cxl/cxl-mailbox-utils.c  | 110 
> >  include/hw/cxl/cxl_device.h |  16 ++
> >  2 files changed, 126 insertions(+)
> > 
> > diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> > index ba1d9901df..88e3b733e3 100644
> > --- a/hw/cxl/cxl-mailbox-utils.c
> > +++ b/hw/cxl/cxl-mailbox-utils.c
> > @@ -22,6 +22,7 @@
> >  
> >  #define CXL_CAPACITY_MULTIPLIER   (256 * MiB)
> >  #define CXL_DC_EVENT_LOG_SIZE 8
> > +#define CXL_SPEC_AFTER_R30
> As below. Drop this.  Kernel code needs to be able to cope with newer specs
> than it understands anyway so should be fine with the larger records 
> (otherwise
> it's buggy and needs fixing!) 

Will remove it.
> 
> >  
> >  /*
> >   * How to add a new command, example. The command set FOO, with cmd BAR.
> > @@ -80,6 +81,8 @@ enum {
> >  #define GET_POISON_LIST0x0
> >  #define INJECT_POISON  0x1
> >  #define CLEAR_POISON   0x2
> > +DCD_CONFIG  = 0x48,
> > +#define GET_DC_CONFIG  0x0
> >  PHYSICAL_SWITCH = 0x51,
> >  #define IDENTIFY_SWITCH_DEVICE  0x0
> >  #define GET_PHYSICAL_PORT_STATE 0x1
> > @@ -1238,6 +1241,103 @@ static CXLRetCode cmd_media_clear_poison(const 
> > struct cxl_cmd *cmd,
> >  return CXL_MBOX_SUCCESS;
> >  }
> >  
> > +/*
> > + * CXL r3.1 section 8.2.9.9.9.1: Get Dynamic Capacity Configuration
> > + * (Opcode: 4800h)
> > + */
> > +static CXLRetCode cmd_dcd_get_dyn_cap_config(const struct cxl_cmd *cmd,
> > + uint8_t *payload_in,
> > + size_t len_in,
> > + uint8_t *payload_out,
> > + size_t *len_out,
> > + CXLCCI *cci)
> > +{
> > +CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
> > +struct get_dyn_cap_config_in_pl {
> Type not needed - see below. 
> > +uint8_t region_cnt;
> > +uint8_t start_region_id;
> > +} QEMU_PACKED;
>} QEMU_PACKED *in;

Get your point, it seems I followed the wrong example like
cmd_media_clear_poison and cmd_inject_poison :-<

Fan

> 
> > +
> > +struct get_dyn_cap_config_out_pl {
> Don't think giving this a type is necessary - see below.
> > +uint8_t num_regions;
> > +uint8_t regions_returned;
> > +uint8_t rsvd1[6];
> > +struct {
> > +uint64_t base;
> > +uint64_t decode_len;
> > +uint64_t region_len;
> > +uint64_t block_size;
> > +uint32_t dsmadhandle;
> > +uint8_t flags;
> > +uint8_t rsvd2[3];
> > +} QEMU_PACKED records[];
> > +/*
> > + * if cxl spec version >= 3.1, extra output payload as defined
> > + * in struct get_dyn_cap_config_out_pl_extra comes here.
> > + */
> > +} QEMU_PACKED;
> } QEMU_PACKED *out;
> > +
> > +struct get_dyn_cap_config_in_pl *in = (void *)payload_in;
> > +struct get_dyn_cap_config_out_pl *out = (void *)payload_out;
> 
> We've (mostly) use the (void *) casting where we haven't given the structures
> a type.  I think I'd prefer we kept to that style for consistency.
> 
> There is an argument we should have given all these types
> for readability reasons and to avoid casting via void * but
> we have gone this way now - with the exception of
> the poison list - oops.   
> 
> > +uint16_t record_count = 0;
> > +uint16_t i;
> > +uint16_t out_pl_len;
> > +uint8_t start_region_id = in->start_region_id;
> > +#ifdef CXL_SPEC_AFTER_R30
> 
> Handy for testing, but I'd drop the ifdef for the final
> version.  We don't need to support old specs.
> 
> > +struct get_dyn_cap_config_out_pl_extra {
> > +uint32_t num_extents_supported;
> > +uint32_t num_extents_available;
> > +uint32_t num_tags_supported;
> > +uint32_t num_tags_available;
> > +} QEMU_PACKED;
> > +struct get_dyn_cap_config_out_pl_extra *extra_out;
> As above, anonymous structure should work ok.
> > +#endif
> > +
> > +if (start_region_id >= ct3d->dc.num_regions) {
> > +return CXL_MBOX_INVALID_INPUT;
> > +}
> > +
> > +

Re: [PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-02-26 Thread Jonathan Cameron via
On Wed, 21 Feb 2024 10:15:55 -0800
nifan@gmail.com wrote:

> From: Fan Ni 
> 
> Per cxl spec r3.1, add dynamic capacity region representative based on
> Table 8-165 and extend the cxl type3 device definition to include dc region
> information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
> Configuration' mailbox support.
> 
> Note: decode_len of a dc region is aligned to 256*MiB, divided by
> 256 * MiB before returned to the host for "Get Dynamic Capacity Configuration"
> mailbox command.
> 
> Signed-off-by: Fan Ni 
Hi Fan,

A few comments inline.

Jonathan

> ---
>  hw/cxl/cxl-mailbox-utils.c  | 110 
>  include/hw/cxl/cxl_device.h |  16 ++
>  2 files changed, 126 insertions(+)
> 
> diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> index ba1d9901df..88e3b733e3 100644
> --- a/hw/cxl/cxl-mailbox-utils.c
> +++ b/hw/cxl/cxl-mailbox-utils.c
> @@ -22,6 +22,7 @@
>  
>  #define CXL_CAPACITY_MULTIPLIER   (256 * MiB)
>  #define CXL_DC_EVENT_LOG_SIZE 8
> +#define CXL_SPEC_AFTER_R30
As below. Drop this.  Kernel code needs to be able to cope with newer specs
than it understands anyway so should be fine with the larger records (otherwise
it's buggy and needs fixing!) 

>  
>  /*
>   * How to add a new command, example. The command set FOO, with cmd BAR.
> @@ -80,6 +81,8 @@ enum {
>  #define GET_POISON_LIST0x0
>  #define INJECT_POISON  0x1
>  #define CLEAR_POISON   0x2
> +DCD_CONFIG  = 0x48,
> +#define GET_DC_CONFIG  0x0
>  PHYSICAL_SWITCH = 0x51,
>  #define IDENTIFY_SWITCH_DEVICE  0x0
>  #define GET_PHYSICAL_PORT_STATE 0x1
> @@ -1238,6 +1241,103 @@ static CXLRetCode cmd_media_clear_poison(const struct 
> cxl_cmd *cmd,
>  return CXL_MBOX_SUCCESS;
>  }
>  
> +/*
> + * CXL r3.1 section 8.2.9.9.9.1: Get Dynamic Capacity Configuration
> + * (Opcode: 4800h)
> + */
> +static CXLRetCode cmd_dcd_get_dyn_cap_config(const struct cxl_cmd *cmd,
> + uint8_t *payload_in,
> + size_t len_in,
> + uint8_t *payload_out,
> + size_t *len_out,
> + CXLCCI *cci)
> +{
> +CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
> +struct get_dyn_cap_config_in_pl {
Type not needed - see below. 
> +uint8_t region_cnt;
> +uint8_t start_region_id;
> +} QEMU_PACKED;
   } QEMU_PACKED *in;

> +
> +struct get_dyn_cap_config_out_pl {
Don't think giving this a type is necessary - see below.
> +uint8_t num_regions;
> +uint8_t regions_returned;
> +uint8_t rsvd1[6];
> +struct {
> +uint64_t base;
> +uint64_t decode_len;
> +uint64_t region_len;
> +uint64_t block_size;
> +uint32_t dsmadhandle;
> +uint8_t flags;
> +uint8_t rsvd2[3];
> +} QEMU_PACKED records[];
> +/*
> + * if cxl spec version >= 3.1, extra output payload as defined
> + * in struct get_dyn_cap_config_out_pl_extra comes here.
> + */
> +} QEMU_PACKED;
} QEMU_PACKED *out;
> +
> +struct get_dyn_cap_config_in_pl *in = (void *)payload_in;
> +struct get_dyn_cap_config_out_pl *out = (void *)payload_out;

We've (mostly) use the (void *) casting where we haven't given the structures
a type.  I think I'd prefer we kept to that style for consistency.

There is an argument we should have given all these types
for readability reasons and to avoid casting via void * but
we have gone this way now - with the exception of
the poison list - oops.   

> +uint16_t record_count = 0;
> +uint16_t i;
> +uint16_t out_pl_len;
> +uint8_t start_region_id = in->start_region_id;
> +#ifdef CXL_SPEC_AFTER_R30

Handy for testing, but I'd drop the ifdef for the final
version.  We don't need to support old specs.

> +struct get_dyn_cap_config_out_pl_extra {
> +uint32_t num_extents_supported;
> +uint32_t num_extents_available;
> +uint32_t num_tags_supported;
> +uint32_t num_tags_available;
> +} QEMU_PACKED;
> +struct get_dyn_cap_config_out_pl_extra *extra_out;
As above, anonymous structure should work ok.
> +#endif
> +
> +if (start_region_id >= ct3d->dc.num_regions) {
> +return CXL_MBOX_INVALID_INPUT;
> +}
> +
> +record_count = MIN(ct3d->dc.num_regions - in->start_region_id,
> +in->region_cnt);
> +
> +out_pl_len = sizeof(*out) + record_count * sizeof(out->records[0]);
> +#ifdef CXL_SPEC_AFTER_R30
> +extra_out = (struct get_dyn_cap_config_out_pl_extra *)(payload_out +
> +out_pl_len);
> +out_pl_len += sizeof(struct get_dyn_cap_config_out_pl_extra);
> +#endif
> +assert(out_pl_len <= CXL_MAILBOX_MAX_PAYLOAD_SIZE);
> +
> +out->num_regions = 

Re: [PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-02-22 Thread fan
On Thu, Feb 22, 2024 at 04:45:25PM +0900, Wonjae Lee wrote:
> On Wed, Feb 21, 2024 at 10:15:55AM -0800, nifan@gmail.com wrote:
> > From: Fan Ni 
> >
> > Per cxl spec r3.1, add dynamic capacity region representative based on
> > Table 8-165 and extend the cxl type3 device definition to include dc region
> > information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
> > Configuration' mailbox support.
> >
> > Note: decode_len of a dc region is aligned to 256*MiB, divided by
> > 256 * MiB before returned to the host for "Get Dynamic Capacity 
> > Configuration"
> > mailbox command.
> >
> > Signed-off-by: Fan Ni 
> > ---
> >  hw/cxl/cxl-mailbox-utils.c  | 110 
> >  include/hw/cxl/cxl_device.h |  16 ++
> >  2 files changed, 126 insertions(+)
> >
> > diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> > index ba1d9901df..88e3b733e3 100644
> > --- a/hw/cxl/cxl-mailbox-utils.c
> > +++ b/hw/cxl/cxl-mailbox-utils.c
> > @@ -22,6 +22,7 @@
> >
> 
> [snip]
> 
> > +#ifdef CXL_SPEC_AFTER_R30
> > +/*FIXME: need to set valid values in the future*/
> > +stq_le_p(_out->num_extents_supported, 0);
> > +stq_le_p(_out->num_extents_available, 0);
> > +stq_le_p(_out->num_tags_supported, 0);
> > +stq_le_p(_out->num_tags_available, 0);
> 
> Hello,
> 
> It's a trivial comment and doesn't have any impact yet, but shouldn't it
> be stl_le_p()?
> 
> Thanks,
> Wonjae

Hi Wonjae,

Thanks for the review. You are right, will fix in the next version.

Fan



RE: [PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-02-22 Thread Wonjae Lee
On Wed, Feb 21, 2024 at 10:15:55AM -0800, nifan@gmail.com wrote:
> From: Fan Ni 
>
> Per cxl spec r3.1, add dynamic capacity region representative based on
> Table 8-165 and extend the cxl type3 device definition to include dc region
> information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
> Configuration' mailbox support.
>
> Note: decode_len of a dc region is aligned to 256*MiB, divided by
> 256 * MiB before returned to the host for "Get Dynamic Capacity Configuration"
> mailbox command.
>
> Signed-off-by: Fan Ni 
> ---
>  hw/cxl/cxl-mailbox-utils.c  | 110 
>  include/hw/cxl/cxl_device.h |  16 ++
>  2 files changed, 126 insertions(+)
>
> diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> index ba1d9901df..88e3b733e3 100644
> --- a/hw/cxl/cxl-mailbox-utils.c
> +++ b/hw/cxl/cxl-mailbox-utils.c
> @@ -22,6 +22,7 @@
>

[snip]

> +#ifdef CXL_SPEC_AFTER_R30
> +/*FIXME: need to set valid values in the future*/
> +stq_le_p(_out->num_extents_supported, 0);
> +stq_le_p(_out->num_extents_available, 0);
> +stq_le_p(_out->num_tags_supported, 0);
> +stq_le_p(_out->num_tags_available, 0);

Hello,

It's a trivial comment and doesn't have any impact yet, but shouldn't it
be stl_le_p()?

Thanks,
Wonjae



[PATCH v4 02/10] hw/cxl/cxl-mailbox-utils: Add dynamic capacity region representative and mailbox command support

2024-02-21 Thread nifan . cxl
From: Fan Ni 

Per cxl spec r3.1, add dynamic capacity region representative based on
Table 8-165 and extend the cxl type3 device definition to include dc region
information. Also, based on info in 8.2.9.9.9.1, add 'Get Dynamic Capacity
Configuration' mailbox support.

Note: decode_len of a dc region is aligned to 256*MiB, divided by
256 * MiB before returned to the host for "Get Dynamic Capacity Configuration"
mailbox command.

Signed-off-by: Fan Ni 
---
 hw/cxl/cxl-mailbox-utils.c  | 110 
 include/hw/cxl/cxl_device.h |  16 ++
 2 files changed, 126 insertions(+)

diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
index ba1d9901df..88e3b733e3 100644
--- a/hw/cxl/cxl-mailbox-utils.c
+++ b/hw/cxl/cxl-mailbox-utils.c
@@ -22,6 +22,7 @@
 
 #define CXL_CAPACITY_MULTIPLIER   (256 * MiB)
 #define CXL_DC_EVENT_LOG_SIZE 8
+#define CXL_SPEC_AFTER_R30
 
 /*
  * How to add a new command, example. The command set FOO, with cmd BAR.
@@ -80,6 +81,8 @@ enum {
 #define GET_POISON_LIST0x0
 #define INJECT_POISON  0x1
 #define CLEAR_POISON   0x2
+DCD_CONFIG  = 0x48,
+#define GET_DC_CONFIG  0x0
 PHYSICAL_SWITCH = 0x51,
 #define IDENTIFY_SWITCH_DEVICE  0x0
 #define GET_PHYSICAL_PORT_STATE 0x1
@@ -1238,6 +1241,103 @@ static CXLRetCode cmd_media_clear_poison(const struct 
cxl_cmd *cmd,
 return CXL_MBOX_SUCCESS;
 }
 
+/*
+ * CXL r3.1 section 8.2.9.9.9.1: Get Dynamic Capacity Configuration
+ * (Opcode: 4800h)
+ */
+static CXLRetCode cmd_dcd_get_dyn_cap_config(const struct cxl_cmd *cmd,
+ uint8_t *payload_in,
+ size_t len_in,
+ uint8_t *payload_out,
+ size_t *len_out,
+ CXLCCI *cci)
+{
+CXLType3Dev *ct3d = CXL_TYPE3(cci->d);
+struct get_dyn_cap_config_in_pl {
+uint8_t region_cnt;
+uint8_t start_region_id;
+} QEMU_PACKED;
+
+struct get_dyn_cap_config_out_pl {
+uint8_t num_regions;
+uint8_t regions_returned;
+uint8_t rsvd1[6];
+struct {
+uint64_t base;
+uint64_t decode_len;
+uint64_t region_len;
+uint64_t block_size;
+uint32_t dsmadhandle;
+uint8_t flags;
+uint8_t rsvd2[3];
+} QEMU_PACKED records[];
+/*
+ * if cxl spec version >= 3.1, extra output payload as defined
+ * in struct get_dyn_cap_config_out_pl_extra comes here.
+ */
+} QEMU_PACKED;
+
+struct get_dyn_cap_config_in_pl *in = (void *)payload_in;
+struct get_dyn_cap_config_out_pl *out = (void *)payload_out;
+uint16_t record_count = 0;
+uint16_t i;
+uint16_t out_pl_len;
+uint8_t start_region_id = in->start_region_id;
+#ifdef CXL_SPEC_AFTER_R30
+struct get_dyn_cap_config_out_pl_extra {
+uint32_t num_extents_supported;
+uint32_t num_extents_available;
+uint32_t num_tags_supported;
+uint32_t num_tags_available;
+} QEMU_PACKED;
+struct get_dyn_cap_config_out_pl_extra *extra_out;
+#endif
+
+if (start_region_id >= ct3d->dc.num_regions) {
+return CXL_MBOX_INVALID_INPUT;
+}
+
+record_count = MIN(ct3d->dc.num_regions - in->start_region_id,
+in->region_cnt);
+
+out_pl_len = sizeof(*out) + record_count * sizeof(out->records[0]);
+#ifdef CXL_SPEC_AFTER_R30
+extra_out = (struct get_dyn_cap_config_out_pl_extra *)(payload_out +
+out_pl_len);
+out_pl_len += sizeof(struct get_dyn_cap_config_out_pl_extra);
+#endif
+assert(out_pl_len <= CXL_MAILBOX_MAX_PAYLOAD_SIZE);
+
+out->num_regions = ct3d->dc.num_regions;
+#ifdef CXL_SPEC_AFTER_R30
+out->regions_returned = record_count;
+#endif
+for (i = 0; i < record_count; i++) {
+stq_le_p(>records[i].base,
+ct3d->dc.regions[start_region_id + i].base);
+stq_le_p(>records[i].decode_len,
+ct3d->dc.regions[start_region_id + i].decode_len /
+CXL_CAPACITY_MULTIPLIER);
+stq_le_p(>records[i].region_len,
+ct3d->dc.regions[start_region_id + i].len);
+stq_le_p(>records[i].block_size,
+ct3d->dc.regions[start_region_id + i].block_size);
+stl_le_p(>records[i].dsmadhandle,
+ct3d->dc.regions[start_region_id + i].dsmadhandle);
+out->records[i].flags = ct3d->dc.regions[start_region_id + i].flags;
+}
+#ifdef CXL_SPEC_AFTER_R30
+/*FIXME: need to set valid values in the future*/
+stq_le_p(_out->num_extents_supported, 0);
+stq_le_p(_out->num_extents_available, 0);
+stq_le_p(_out->num_tags_supported, 0);
+stq_le_p(_out->num_tags_available, 0);
+#endif
+
+*len_out = out_pl_len;
+return CXL_MBOX_SUCCESS;
+}
+