Re: [PATCH RFC v2 03/18] cxl/mem: Read Dynamic capacity configuration from the device

From: Fan Ni
Date: Wed Aug 30 2023 - 17:46:52 EST


On Mon, Aug 28, 2023 at 10:20:54PM -0700, ira.weiny@xxxxxxxxx wrote:
> From: Navneet Singh <navneet.singh@xxxxxxxxx>
>
> Devices can optionally support Dynamic Capacity (DC). These devices are
> known as Dynamic Capacity Devices (DCD).
>
> Implement the DC (opcode 48XXh) mailbox commands as specified in CXL 3.0
> section 8.2.9.8.9. Read the DC configuration and store the DC region
> information in the device state.
>
> Co-developed-by: Navneet Singh <navneet.singh@xxxxxxxxx>
> Signed-off-by: Navneet Singh <navneet.singh@xxxxxxxxx>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> ---
> Changes for v2
> [iweiny: Rebased to latest master type2 work]
> [jonathan: s/dc/dc_resp/]
> [iweiny: Clean up commit message]
> [iweiny: Clean kernel docs]
> [djiang: Fix up cxl_is_dcd_command]
> [djiang: extra blank line]
> [alison: s/total_capacity/cap/ etc...]
> [alison: keep partition flag with partition structures]
> [alison: reformat untenanted_mem declaration]
> [alison: move 'cmd' definition back]
> [alison: fix comment line length]
> [alison: reverse x-tree]
> [jonathan: fix and adjust CXL_DC_REGION_STRLEN]
> [Jonathan/iweiny: Factor out storing each DC region read from the device]
> [Jonathan: place all dcr initializers together]
> [Jonathan/iweiny: flip around the region DPA order check]
> [jonathan: Account for short read of mailbox command]
> [iweiny: use snprintf for region name]
> [iweiny: use '<nil>' for missing region names]
> [iweiny: factor out struct cxl_dc_region_info]
> [iweiny: Split out reading CEL]
> ---
> drivers/cxl/core/mbox.c | 179 +++++++++++++++++++++++++++++++++++++++++++++-
> drivers/cxl/core/region.c | 75 +++++++++++++------
> drivers/cxl/cxl.h | 27 ++++++-
> drivers/cxl/cxlmem.h | 55 +++++++++++++-
> drivers/cxl/pci.c | 4 ++
> 5 files changed, 314 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 554ec97a7c39..d769814f80e2 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -1096,7 +1096,7 @@ int cxl_dev_state_identify(struct cxl_memdev_state *mds)
> if (rc < 0)
> return rc;
>
> - mds->total_bytes =
> + mds->static_cap =
> le64_to_cpu(id.total_capacity) * CXL_CAPACITY_MULTIPLIER;
> mds->volatile_only_bytes =
> le64_to_cpu(id.volatile_capacity) * CXL_CAPACITY_MULTIPLIER;
> @@ -1114,6 +1114,8 @@ int cxl_dev_state_identify(struct cxl_memdev_state *mds)
> mds->poison.max_errors = min_t(u32, val, CXL_POISON_LIST_MAX);
> }
>
> + mds->dc_event_log_size = le16_to_cpu(id.dc_event_log_size);
> +
> return 0;
> }
> EXPORT_SYMBOL_NS_GPL(cxl_dev_state_identify, CXL);
> @@ -1178,6 +1180,165 @@ int cxl_mem_sanitize(struct cxl_memdev_state *mds, u16 cmd)
> }
> EXPORT_SYMBOL_NS_GPL(cxl_mem_sanitize, CXL);
>
> +static int cxl_dc_save_region_info(struct cxl_memdev_state *mds, int index,
> + struct cxl_dc_region_config *region_config)
> +{
> + struct cxl_dc_region_info *dcr = &mds->dc_region[index];
> + struct device *dev = mds->cxlds.dev;
> +
> + dcr->base = le64_to_cpu(region_config->region_base);
> + dcr->decode_len = le64_to_cpu(region_config->region_decode_length);
> + dcr->decode_len *= CXL_CAPACITY_MULTIPLIER;
> + dcr->len = le64_to_cpu(region_config->region_length);
> + dcr->blk_size = le64_to_cpu(region_config->region_block_size);
> + dcr->dsmad_handle = le32_to_cpu(region_config->region_dsmad_handle);
> + dcr->flags = region_config->flags;
> + snprintf(dcr->name, CXL_DC_REGION_STRLEN, "dc%d", index);
> +
> + /* Check regions are in increasing DPA order */
> + if (index > 0) {
> + struct cxl_dc_region_info *prev_dcr = &mds->dc_region[index - 1];
> +
> + if ((prev_dcr->base + prev_dcr->decode_len) > dcr->base) {
> + dev_err(dev,
> + "DPA ordering violation for DC region %d and %d\n",
> + index - 1, index);
> + return -EINVAL;
> + }
> + }
> +
> + /* Check the region is 256 MB aligned */
> + if (!IS_ALIGNED(dcr->base, SZ_256M)) {
> + dev_err(dev, "DC region %d not aligned to 256MB: %#llx\n",
> + index, dcr->base);
> + return -EINVAL;
> + }
> +
> + /* Check Region base and length are aligned to block size */
> + if (!IS_ALIGNED(dcr->base, dcr->blk_size) ||
> + !IS_ALIGNED(dcr->len, dcr->blk_size)) {
> + dev_err(dev, "DC region %d not aligned to %#llx\n", index,
> + dcr->blk_size);
> + return -EINVAL;
> + }

Based on on cxl 3.0 spec: Table 8-126, we may need some extra checks
here:
1. region len <= decode_len
2. region block size should be power of 2 and a multiple of 40H.

Also, if region len or block size is 0, it mentions that DC will not be
available, we may also need to handle that.

Fan

> +
> + dev_dbg(dev,
> + "DC region %s DPA: %#llx LEN: %#llx BLKSZ: %#llx\n",
> + dcr->name, dcr->base, dcr->decode_len, dcr->blk_size);
> +
> + return 0;
> +}
> +
> +/* Returns the number of regions in dc_resp or -ERRNO */
> +static int cxl_get_dc_id(struct cxl_memdev_state *mds, u8 start_region,
> + struct cxl_mbox_dynamic_capacity *dc_resp,
> + size_t dc_resp_size)
> +{
> + struct cxl_mbox_get_dc_config get_dc = (struct cxl_mbox_get_dc_config) {
> + .region_count = CXL_MAX_DC_REGION,
> + .start_region_index = start_region,
> + };
> + struct cxl_mbox_cmd mbox_cmd = (struct cxl_mbox_cmd) {
> + .opcode = CXL_MBOX_OP_GET_DC_CONFIG,
> + .payload_in = &get_dc,
> + .size_in = sizeof(get_dc),
> + .size_out = dc_resp_size,
> + .payload_out = dc_resp,
> + .min_out = 1,
> + };
> + struct device *dev = mds->cxlds.dev;
> + int rc;
> +
> + rc = cxl_internal_send_cmd(mds, &mbox_cmd);
> + if (rc < 0)
> + return rc;
> +
> + rc = dc_resp->avail_region_count - start_region;
> +
> + /*
> + * The number of regions in the payload may have been truncated due to
> + * payload_size limits; if so adjust the count in this query.
> + */
> + if (mbox_cmd.size_out < sizeof(*dc_resp))
> + rc = CXL_REGIONS_RETURNED(mbox_cmd.size_out);
> +
> + dev_dbg(dev, "Read %d/%d DC regions\n", rc, dc_resp->avail_region_count);
> +
> + return rc;
> +}
> +
> +/**
> + * cxl_dev_dynamic_capacity_identify() - Reads the dynamic capacity
> + * information from the device.
> + * @mds: The memory device state
> + *
> + * This will dispatch the get_dynamic_capacity command to the device
> + * and on success populate structures to be exported to sysfs.
> + *
> + * Return: 0 if identify was executed successfully, -ERRNO on error.
> + */
> +int cxl_dev_dynamic_capacity_identify(struct cxl_memdev_state *mds)
> +{
> + struct cxl_mbox_dynamic_capacity *dc_resp;
> + struct device *dev = mds->cxlds.dev;
> + size_t dc_resp_size = mds->payload_size;
> + u8 start_region;
> + int i, rc = 0;
> +
> + for (i = 0; i < CXL_MAX_DC_REGION; i++)
> + snprintf(mds->dc_region[i].name, CXL_DC_REGION_STRLEN, "<nil>");
> +
> + /* Check GET_DC_CONFIG is supported by device */
> + if (!test_bit(CXL_DCD_ENABLED_GET_CONFIG, mds->dcd_cmds)) {
> + dev_dbg(dev, "unsupported cmd: get_dynamic_capacity_config\n");
> + return 0;
> + }
> +
> + dc_resp = kvmalloc(dc_resp_size, GFP_KERNEL);
> + if (!dc_resp)
> + return -ENOMEM;
> +
> + start_region = 0;
> + do {
> + int j;
> +
> + rc = cxl_get_dc_id(mds, start_region, dc_resp, dc_resp_size);
> + if (rc < 0)
> + goto free_resp;
> +
> + mds->nr_dc_region += rc;
> +
> + if (mds->nr_dc_region < 1 || mds->nr_dc_region > CXL_MAX_DC_REGION) {
> + dev_err(dev, "Invalid num of dynamic capacity regions %d\n",
> + mds->nr_dc_region);
> + rc = -EINVAL;
> + goto free_resp;
> + }
> +
> + for (i = start_region, j = 0; i < mds->nr_dc_region; i++, j++) {
> + rc = cxl_dc_save_region_info(mds, i, &dc_resp->region[j]);
> + if (rc)
> + goto free_resp;
> + }
> +
> + start_region = mds->nr_dc_region;
> +
> + } while (mds->nr_dc_region < dc_resp->avail_region_count);
> +
> + mds->dynamic_cap =
> + mds->dc_region[mds->nr_dc_region - 1].base +
> + mds->dc_region[mds->nr_dc_region - 1].decode_len -
> + mds->dc_region[0].base;
> + dev_dbg(dev, "Total dynamic capacity: %#llx\n", mds->dynamic_cap);
> +
> +free_resp:
> + kfree(dc_resp);
> + if (rc)
> + dev_err(dev, "Failed to get DC info: %d\n", rc);
> + return rc;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_dev_dynamic_capacity_identify, CXL);
> +
> static int add_dpa_res(struct device *dev, struct resource *parent,
> struct resource *res, resource_size_t start,
> resource_size_t size, const char *type)
> @@ -1208,8 +1369,12 @@ int cxl_mem_create_range_info(struct cxl_memdev_state *mds)
> {
> struct cxl_dev_state *cxlds = &mds->cxlds;
> struct device *dev = cxlds->dev;
> + size_t untenanted_mem;
> int rc;
>
> + untenanted_mem = mds->dc_region[0].base - mds->static_cap;
> + mds->total_bytes = mds->static_cap + untenanted_mem + mds->dynamic_cap;
> +
> if (!cxlds->media_ready) {
> cxlds->dpa_res = DEFINE_RES_MEM(0, 0);
> cxlds->ram_res = DEFINE_RES_MEM(0, 0);
> @@ -1217,8 +1382,16 @@ int cxl_mem_create_range_info(struct cxl_memdev_state *mds)
> return 0;
> }
>
> - cxlds->dpa_res =
> - (struct resource)DEFINE_RES_MEM(0, mds->total_bytes);
> + cxlds->dpa_res = (struct resource)DEFINE_RES_MEM(0, mds->total_bytes);
> +
> + for (int i = 0; i < mds->nr_dc_region; i++) {
> + struct cxl_dc_region_info *dcr = &mds->dc_region[i];
> +
> + rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->dc_res[i],
> + dcr->base, dcr->decode_len, dcr->name);
> + if (rc)
> + return rc;
> + }
>
> if (mds->partition_align_bytes == 0) {
> rc = add_dpa_res(dev, &cxlds->dpa_res, &cxlds->ram_res, 0,
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 252bc8e1f103..75041903b72c 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -46,7 +46,7 @@ static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
> rc = down_read_interruptible(&cxl_region_rwsem);
> if (rc)
> return rc;
> - if (cxlr->mode != CXL_DECODER_PMEM)
> + if (cxlr->mode != CXL_REGION_PMEM)
> rc = sysfs_emit(buf, "\n");
> else
> rc = sysfs_emit(buf, "%pUb\n", &p->uuid);
> @@ -359,7 +359,7 @@ static umode_t cxl_region_visible(struct kobject *kobj, struct attribute *a,
> * Support tooling that expects to find a 'uuid' attribute for all
> * regions regardless of mode.
> */
> - if (a == &dev_attr_uuid.attr && cxlr->mode != CXL_DECODER_PMEM)
> + if (a == &dev_attr_uuid.attr && cxlr->mode != CXL_REGION_PMEM)
> return 0444;
> return a->mode;
> }
> @@ -537,7 +537,7 @@ static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
> {
> struct cxl_region *cxlr = to_cxl_region(dev);
>
> - return sysfs_emit(buf, "%s\n", cxl_decoder_mode_name(cxlr->mode));
> + return sysfs_emit(buf, "%s\n", cxl_region_mode_name(cxlr->mode));
> }
> static DEVICE_ATTR_RO(mode);
>
> @@ -563,7 +563,7 @@ static int alloc_hpa(struct cxl_region *cxlr, resource_size_t size)
>
> /* ways, granularity and uuid (if PMEM) need to be set before HPA */
> if (!p->interleave_ways || !p->interleave_granularity ||
> - (cxlr->mode == CXL_DECODER_PMEM && uuid_is_null(&p->uuid)))
> + (cxlr->mode == CXL_REGION_PMEM && uuid_is_null(&p->uuid)))
> return -ENXIO;
>
> div_u64_rem(size, SZ_256M * p->interleave_ways, &remainder);
> @@ -1765,6 +1765,17 @@ static int cxl_region_sort_targets(struct cxl_region *cxlr)
> return rc;
> }
>
> +static bool cxl_modes_compatible(enum cxl_region_mode rmode,
> + enum cxl_decoder_mode dmode)
> +{
> + if (rmode == CXL_REGION_RAM && dmode == CXL_DECODER_RAM)
> + return true;
> + if (rmode == CXL_REGION_PMEM && dmode == CXL_DECODER_PMEM)
> + return true;
> +
> + return false;
> +}
> +
> static int cxl_region_attach(struct cxl_region *cxlr,
> struct cxl_endpoint_decoder *cxled, int pos)
> {
> @@ -1778,9 +1789,11 @@ static int cxl_region_attach(struct cxl_region *cxlr,
> lockdep_assert_held_write(&cxl_region_rwsem);
> lockdep_assert_held_read(&cxl_dpa_rwsem);
>
> - if (cxled->mode != cxlr->mode) {
> - dev_dbg(&cxlr->dev, "%s region mode: %d mismatch: %d\n",
> - dev_name(&cxled->cxld.dev), cxlr->mode, cxled->mode);
> + if (!cxl_modes_compatible(cxlr->mode, cxled->mode)) {
> + dev_dbg(&cxlr->dev, "%s region mode: %s mismatch decoder: %s\n",
> + dev_name(&cxled->cxld.dev),
> + cxl_region_mode_name(cxlr->mode),
> + cxl_decoder_mode_name(cxled->mode));
> return -EINVAL;
> }
>
> @@ -2234,7 +2247,7 @@ static struct cxl_region *cxl_region_alloc(struct cxl_root_decoder *cxlrd, int i
> * devm_cxl_add_region - Adds a region to a decoder
> * @cxlrd: root decoder
> * @id: memregion id to create, or memregion_free() on failure
> - * @mode: mode for the endpoint decoders of this region
> + * @mode: mode of this region
> * @type: select whether this is an expander or accelerator (type-2 or type-3)
> *
> * This is the second step of region initialization. Regions exist within an
> @@ -2245,7 +2258,7 @@ static struct cxl_region *cxl_region_alloc(struct cxl_root_decoder *cxlrd, int i
> */
> static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd,
> int id,
> - enum cxl_decoder_mode mode,
> + enum cxl_region_mode mode,
> enum cxl_decoder_type type)
> {
> struct cxl_port *port = to_cxl_port(cxlrd->cxlsd.cxld.dev.parent);
> @@ -2254,11 +2267,12 @@ static struct cxl_region *devm_cxl_add_region(struct cxl_root_decoder *cxlrd,
> int rc;
>
> switch (mode) {
> - case CXL_DECODER_RAM:
> - case CXL_DECODER_PMEM:
> + case CXL_REGION_RAM:
> + case CXL_REGION_PMEM:
> break;
> default:
> - dev_err(&cxlrd->cxlsd.cxld.dev, "unsupported mode %d\n", mode);
> + dev_err(&cxlrd->cxlsd.cxld.dev, "unsupported mode %s\n",
> + cxl_region_mode_name(mode));
> return ERR_PTR(-EINVAL);
> }
>
> @@ -2308,7 +2322,7 @@ static ssize_t create_ram_region_show(struct device *dev,
> }
>
> static struct cxl_region *__create_region(struct cxl_root_decoder *cxlrd,
> - int id, enum cxl_decoder_mode mode,
> + int id, enum cxl_region_mode mode,
> enum cxl_decoder_type type)
> {
> int rc;
> @@ -2337,7 +2351,7 @@ static ssize_t create_pmem_region_store(struct device *dev,
> if (rc != 1)
> return -EINVAL;
>
> - cxlr = __create_region(cxlrd, id, CXL_DECODER_PMEM,
> + cxlr = __create_region(cxlrd, id, CXL_REGION_PMEM,
> CXL_DECODER_HOSTONLYMEM);
> if (IS_ERR(cxlr))
> return PTR_ERR(cxlr);
> @@ -2358,7 +2372,7 @@ static ssize_t create_ram_region_store(struct device *dev,
> if (rc != 1)
> return -EINVAL;
>
> - cxlr = __create_region(cxlrd, id, CXL_DECODER_RAM,
> + cxlr = __create_region(cxlrd, id, CXL_REGION_RAM,
> CXL_DECODER_HOSTONLYMEM);
> if (IS_ERR(cxlr))
> return PTR_ERR(cxlr);
> @@ -2886,10 +2900,31 @@ static void construct_region_end(void)
> up_write(&cxl_region_rwsem);
> }
>
> +static enum cxl_region_mode
> +cxl_decoder_to_region_mode(enum cxl_decoder_mode mode)
> +{
> + switch (mode) {
> + case CXL_DECODER_NONE:
> + return CXL_REGION_NONE;
> + case CXL_DECODER_RAM:
> + return CXL_REGION_RAM;
> + case CXL_DECODER_PMEM:
> + return CXL_REGION_PMEM;
> + case CXL_DECODER_DEAD:
> + return CXL_REGION_DEAD;
> + case CXL_DECODER_MIXED:
> + default:
> + return CXL_REGION_MIXED;
> + }
> +
> + return CXL_REGION_MIXED;
> +}
> +
> static struct cxl_region *
> construct_region_begin(struct cxl_root_decoder *cxlrd,
> struct cxl_endpoint_decoder *cxled)
> {
> + enum cxl_region_mode mode = cxl_decoder_to_region_mode(cxled->mode);
> struct cxl_memdev *cxlmd = cxled_to_memdev(cxled);
> struct cxl_region_params *p;
> struct cxl_region *cxlr;
> @@ -2897,7 +2932,7 @@ construct_region_begin(struct cxl_root_decoder *cxlrd,
>
> do {
> cxlr = __create_region(cxlrd, atomic_read(&cxlrd->region_id),
> - cxled->mode, cxled->cxld.target_type);
> + mode, cxled->cxld.target_type);
> } while (IS_ERR(cxlr) && PTR_ERR(cxlr) == -EBUSY);
>
> if (IS_ERR(cxlr)) {
> @@ -3200,9 +3235,9 @@ static int cxl_region_probe(struct device *dev)
> return rc;
>
> switch (cxlr->mode) {
> - case CXL_DECODER_PMEM:
> + case CXL_REGION_PMEM:
> return devm_cxl_add_pmem_region(cxlr);
> - case CXL_DECODER_RAM:
> + case CXL_REGION_RAM:
> /*
> * The region can not be manged by CXL if any portion of
> * it is already online as 'System RAM'
> @@ -3223,8 +3258,8 @@ static int cxl_region_probe(struct device *dev)
> /* HDM-H routes to device-dax */
> return devm_cxl_add_dax_region(cxlr);
> default:
> - dev_dbg(&cxlr->dev, "unsupported region mode: %d\n",
> - cxlr->mode);
> + dev_dbg(&cxlr->dev, "unsupported region mode: %s\n",
> + cxl_region_mode_name(cxlr->mode));
> return -ENXIO;
> }
> }
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index cd4a9ffdacc7..ed282dcd5cf5 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -374,6 +374,28 @@ static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)
> return "mixed";
> }
>
> +enum cxl_region_mode {
> + CXL_REGION_NONE,
> + CXL_REGION_RAM,
> + CXL_REGION_PMEM,
> + CXL_REGION_MIXED,
> + CXL_REGION_DEAD,
> +};
> +
> +static inline const char *cxl_region_mode_name(enum cxl_region_mode mode)
> +{
> + static const char * const names[] = {
> + [CXL_REGION_NONE] = "none",
> + [CXL_REGION_RAM] = "ram",
> + [CXL_REGION_PMEM] = "pmem",
> + [CXL_REGION_MIXED] = "mixed",
> + };
> +
> + if (mode >= CXL_REGION_NONE && mode <= CXL_REGION_MIXED)
> + return names[mode];
> + return "mixed";
> +}
> +
> /*
> * Track whether this decoder is reserved for region autodiscovery, or
> * free for userspace provisioning.
> @@ -502,7 +524,8 @@ struct cxl_region_params {
> * struct cxl_region - CXL region
> * @dev: This region's device
> * @id: This region's id. Id is globally unique across all regions
> - * @mode: Endpoint decoder allocation / access mode
> + * @mode: Region mode which defines which endpoint decoder mode the region is
> + * compatible with
> * @type: Endpoint decoder target type
> * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
> * @cxlr_pmem: (for pmem regions) cached copy of the nvdimm bridge
> @@ -512,7 +535,7 @@ struct cxl_region_params {
> struct cxl_region {
> struct device dev;
> int id;
> - enum cxl_decoder_mode mode;
> + enum cxl_region_mode mode;
> enum cxl_decoder_type type;
> struct cxl_nvdimm_bridge *cxl_nvb;
> struct cxl_pmem_region *cxlr_pmem;
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index 5f2e65204bf9..8c8f47b397ab 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -396,6 +396,7 @@ enum cxl_devtype {
> CXL_DEVTYPE_CLASSMEM,
> };
>
> +#define CXL_MAX_DC_REGION 8
> /**
> * struct cxl_dev_state - The driver device state
> *
> @@ -412,6 +413,8 @@ enum cxl_devtype {
> * @dpa_res: Overall DPA resource tree for the device
> * @pmem_res: Active Persistent memory capacity configuration
> * @ram_res: Active Volatile memory capacity configuration
> + * @dc_res: Active Dynamic Capacity memory configuration for each possible
> + * region
> * @component_reg_phys: register base of component registers
> * @serial: PCIe Device Serial Number
> * @type: Generic Memory Class device or Vendor Specific Memory device
> @@ -426,11 +429,23 @@ struct cxl_dev_state {
> struct resource dpa_res;
> struct resource pmem_res;
> struct resource ram_res;
> + struct resource dc_res[CXL_MAX_DC_REGION];
> resource_size_t component_reg_phys;
> u64 serial;
> enum cxl_devtype type;
> };
>
> +#define CXL_DC_REGION_STRLEN 7
> +struct cxl_dc_region_info {
> + u64 base;
> + u64 decode_len;
> + u64 len;
> + u64 blk_size;
> + u32 dsmad_handle;
> + u8 flags;
> + u8 name[CXL_DC_REGION_STRLEN];
> +};
> +
> /**
> * struct cxl_memdev_state - Generic Type-3 Memory Device Class driver data
> *
> @@ -449,6 +464,8 @@ struct cxl_dev_state {
> * @enabled_cmds: Hardware commands found enabled in CEL.
> * @exclusive_cmds: Commands that are kernel-internal only
> * @total_bytes: sum of all possible capacities
> + * @static_cap: Sum of RAM and PMEM capacities
> + * @dynamic_cap: Complete DPA range occupied by DC regions
> * @volatile_only_bytes: hard volatile capacity
> * @persistent_only_bytes: hard persistent capacity
> * @partition_align_bytes: alignment size for partition-able capacity
> @@ -456,6 +473,10 @@ struct cxl_dev_state {
> * @active_persistent_bytes: sum of hard + soft persistent
> * @next_volatile_bytes: volatile capacity change pending device reset
> * @next_persistent_bytes: persistent capacity change pending device reset
> + * @nr_dc_region: number of DC regions implemented in the memory device
> + * @dc_region: array containing info about the DC regions
> + * @dc_event_log_size: The number of events the device can store in the
> + * Dynamic Capacity Event Log before it overflows
> * @event: event log driver state
> * @poison: poison driver state info
> * @fw: firmware upload / activation state
> @@ -473,7 +494,10 @@ struct cxl_memdev_state {
> DECLARE_BITMAP(dcd_cmds, CXL_DCD_ENABLED_MAX);
> DECLARE_BITMAP(enabled_cmds, CXL_MEM_COMMAND_ID_MAX);
> DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
> +
> u64 total_bytes;
> + u64 static_cap;
> + u64 dynamic_cap;
> u64 volatile_only_bytes;
> u64 persistent_only_bytes;
> u64 partition_align_bytes;
> @@ -481,6 +505,11 @@ struct cxl_memdev_state {
> u64 active_persistent_bytes;
> u64 next_volatile_bytes;
> u64 next_persistent_bytes;
> +
> + u8 nr_dc_region;
> + struct cxl_dc_region_info dc_region[CXL_MAX_DC_REGION];
> + size_t dc_event_log_size;
> +
> struct cxl_event_state event;
> struct cxl_poison_state poison;
> struct cxl_security_state security;
> @@ -587,6 +616,7 @@ struct cxl_mbox_identify {
> __le16 inject_poison_limit;
> u8 poison_caps;
> u8 qos_telemetry_caps;
> + __le16 dc_event_log_size;
> } __packed;
>
> /*
> @@ -741,9 +771,31 @@ struct cxl_mbox_set_partition_info {
> __le64 volatile_capacity;
> u8 flags;
> } __packed;
> -
> #define CXL_SET_PARTITION_IMMEDIATE_FLAG BIT(0)
>
> +struct cxl_mbox_get_dc_config {
> + u8 region_count;
> + u8 start_region_index;
> +} __packed;
> +
> +/* See CXL 3.0 Table 125 get dynamic capacity config Output Payload */
> +struct cxl_mbox_dynamic_capacity {
> + u8 avail_region_count;
> + u8 rsvd[7];
> + struct cxl_dc_region_config {
> + __le64 region_base;
> + __le64 region_decode_length;
> + __le64 region_length;
> + __le64 region_block_size;
> + __le32 region_dsmad_handle;
> + u8 flags;
> + u8 rsvd[3];
> + } __packed region[];
> +} __packed;
> +#define CXL_DYNAMIC_CAPACITY_SANITIZE_ON_RELEASE_FLAG BIT(0)
> +#define CXL_REGIONS_RETURNED(size_out) \
> + ((size_out - 8) / sizeof(struct cxl_dc_region_config))
> +
> /* Set Timestamp CXL 3.0 Spec 8.2.9.4.2 */
> struct cxl_mbox_set_timestamp_in {
> __le64 timestamp;
> @@ -867,6 +919,7 @@ enum {
> int cxl_internal_send_cmd(struct cxl_memdev_state *mds,
> struct cxl_mbox_cmd *cmd);
> int cxl_dev_state_identify(struct cxl_memdev_state *mds);
> +int cxl_dev_dynamic_capacity_identify(struct cxl_memdev_state *mds);
> int cxl_await_media_ready(struct cxl_dev_state *cxlds);
> int cxl_enumerate_cmds(struct cxl_memdev_state *mds);
> int cxl_mem_create_range_info(struct cxl_memdev_state *mds);
> diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
> index 5242dbf0044d..a9b110ff1176 100644
> --- a/drivers/cxl/pci.c
> +++ b/drivers/cxl/pci.c
> @@ -879,6 +879,10 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> if (rc)
> return rc;
>
> + rc = cxl_dev_dynamic_capacity_identify(mds);
> + if (rc)
> + return rc;
> +
> rc = cxl_mem_create_range_info(mds);
> if (rc)
> return rc;
>
> --
> 2.41.0
>