diff options
| -rw-r--r-- | drivers/cxl/core/cdat.c | 497 | ||||
| -rw-r--r-- | drivers/cxl/core/core.h | 4 | ||||
| -rw-r--r-- | drivers/cxl/core/pci.c | 23 | ||||
| -rw-r--r-- | drivers/cxl/core/port.c | 20 | ||||
| -rw-r--r-- | drivers/cxl/core/region.c | 2 | ||||
| -rw-r--r-- | drivers/cxl/cxl.h | 1 |
6 files changed, 537 insertions, 10 deletions
diff --git a/drivers/cxl/core/cdat.c b/drivers/cxl/core/cdat.c index 7bbf266a1612..ef1621d40f05 100644 --- a/drivers/cxl/core/cdat.c +++ b/drivers/cxl/core/cdat.c @@ -547,19 +547,37 @@ void cxl_coordinates_combine(struct access_coordinate *out, MODULE_IMPORT_NS(CXL); -void cxl_region_perf_data_calculate(struct cxl_region *cxlr, - struct cxl_endpoint_decoder *cxled) +static void cxl_bandwidth_add(struct access_coordinate *coord, + struct access_coordinate *c1, + struct access_coordinate *c2) +{ + for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { + coord[i].read_bandwidth = c1[i].read_bandwidth + + c2[i].read_bandwidth; + coord[i].write_bandwidth = c1[i].write_bandwidth + + c2[i].write_bandwidth; + } +} + +static bool dpa_perf_contains(struct cxl_dpa_perf *perf, + struct resource *dpa_res) { - struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); - struct cxl_dev_state *cxlds = cxlmd->cxlds; - struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds); struct range dpa = { - .start = cxled->dpa_res->start, - .end = cxled->dpa_res->end, + .start = dpa_res->start, + .end = dpa_res->end, }; + + return range_contains(&perf->dpa_range, &dpa); +} + +static struct cxl_dpa_perf *cxled_get_dpa_perf(struct cxl_endpoint_decoder *cxled, + enum cxl_decoder_mode mode) +{ + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds); struct cxl_dpa_perf *perf; - switch (cxlr->mode) { + switch (mode) { case CXL_DECODER_RAM: perf = &mds->ram_perf; break; @@ -567,12 +585,473 @@ void cxl_region_perf_data_calculate(struct cxl_region *cxlr, perf = &mds->pmem_perf; break; default: + return ERR_PTR(-EINVAL); + } + + if (!dpa_perf_contains(perf, cxled->dpa_res)) + return ERR_PTR(-EINVAL); + + return perf; +} + +/* + * Transient context for containing the current calculation of bandwidth when + * doing walking the port hierarchy to deal with shared upstream link. + */ +struct cxl_perf_ctx { + struct access_coordinate coord[ACCESS_COORDINATE_MAX]; + struct cxl_port *port; +}; + +/** + * cxl_endpoint_gather_bandwidth - collect all the endpoint bandwidth in an xarray + * @cxlr: CXL region for the bandwidth calculation + * @cxled: endpoint decoder to start on + * @usp_xa: (output) the xarray that collects all the bandwidth coordinates + * indexed by the upstream device with data of 'struct cxl_perf_ctx'. + * @gp_is_root: (output) bool of whether the grandparent is cxl root. + * + * Return: 0 for success or -errno + * + * Collects aggregated endpoint bandwidth and store the bandwidth in + * an xarray indexed by the upstream device of the switch or the RP + * device. Each endpoint consists the minimum of the bandwidth from DSLBIS + * from the endpoint CDAT, the endpoint upstream link bandwidth, and the + * bandwidth from the SSLBIS of the switch CDAT for the switch upstream port to + * the downstream port that's associated with the endpoint. If the + * device is directly connected to a RP, then no SSLBIS is involved. + */ +static int cxl_endpoint_gather_bandwidth(struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled, + struct xarray *usp_xa, + bool *gp_is_root) +{ + struct cxl_port *endpoint = to_cxl_port(cxled->cxld.dev.parent); + struct cxl_port *parent_port = to_cxl_port(endpoint->dev.parent); + struct cxl_port *gp_port = to_cxl_port(parent_port->dev.parent); + struct access_coordinate pci_coord[ACCESS_COORDINATE_MAX]; + struct access_coordinate sw_coord[ACCESS_COORDINATE_MAX]; + struct access_coordinate ep_coord[ACCESS_COORDINATE_MAX]; + struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); + struct cxl_dev_state *cxlds = cxlmd->cxlds; + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + struct cxl_perf_ctx *perf_ctx; + struct cxl_dpa_perf *perf; + unsigned long index; + void *ptr; + int rc; + + if (cxlds->rcd) + return -ENODEV; + + perf = cxled_get_dpa_perf(cxled, cxlr->mode); + if (IS_ERR(perf)) + return PTR_ERR(perf); + + gp_port = to_cxl_port(parent_port->dev.parent); + *gp_is_root = is_cxl_root(gp_port); + + /* + * If the grandparent is cxl root, then index is the root port, + * otherwise it's the parent switch upstream device. + */ + if (*gp_is_root) + index = (unsigned long)endpoint->parent_dport->dport_dev; + else + index = (unsigned long)parent_port->uport_dev; + + perf_ctx = xa_load(usp_xa, index); + if (!perf_ctx) { + struct cxl_perf_ctx *c __free(kfree) = + kzalloc(sizeof(*perf_ctx), GFP_KERNEL); + + if (!c) + return -ENOMEM; + ptr = xa_store(usp_xa, index, c, GFP_KERNEL); + if (xa_is_err(ptr)) + return xa_err(ptr); + perf_ctx = no_free_ptr(c); + perf_ctx->port = parent_port; + } + + /* Direct upstream link from EP bandwidth */ + rc = cxl_pci_get_bandwidth(pdev, pci_coord); + if (rc < 0) + return rc; + + /* + * Min of upstream link bandwidth and Endpoint CDAT bandwidth from + * DSLBIS. + */ + cxl_coordinates_combine(ep_coord, pci_coord, perf->cdat_coord); + + /* + * If grandparent port is root, then there's no switch involved and + * the endpoint is connected to a root port. + */ + if (!*gp_is_root) { + /* + * Retrieve the switch SSLBIS for switch downstream port + * associated with the endpoint bandwidth. + */ + rc = cxl_port_get_switch_dport_bandwidth(endpoint, sw_coord); + if (rc) + return rc; + + /* + * Min of the earlier coordinates with the switch SSLBIS + * bandwidth + */ + cxl_coordinates_combine(ep_coord, ep_coord, sw_coord); + } + + /* + * Aggregate the computed bandwidth with the current aggregated bandwidth + * of the endpoints with the same switch upstream device or RP. + */ + cxl_bandwidth_add(perf_ctx->coord, perf_ctx->coord, ep_coord); + + return 0; +} + +static void free_perf_xa(struct xarray *xa) +{ + struct cxl_perf_ctx *ctx; + unsigned long index; + + if (!xa) + return; + + xa_for_each(xa, index, ctx) + kfree(ctx); + xa_destroy(xa); + kfree(xa); +} +DEFINE_FREE(free_perf_xa, struct xarray *, if (_T) free_perf_xa(_T)) + +/** + * cxl_switch_gather_bandwidth - collect all the bandwidth at switch level in an xarray + * @cxlr: The region being operated on + * @input_xa: xarray indexed by upstream device of a switch with data of 'struct + * cxl_perf_ctx' + * @gp_is_root: (output) bool of whether the grandparent is cxl root. + * + * Return: a xarray of resulting cxl_perf_ctx per parent switch or root port + * or ERR_PTR(-errno) + * + * Iterate through the xarray. Take the minimum of the downstream calculated + * bandwidth, the upstream link bandwidth, and the SSLBIS of the upstream + * switch if exists. Sum the resulting bandwidth under the switch upstream + * device or a RP device. The function can be iterated over multiple switches + * if the switches are present. + */ +static struct xarray *cxl_switch_gather_bandwidth(struct cxl_region *cxlr, + struct xarray *input_xa, + bool *gp_is_root) +{ + struct xarray *res_xa __free(free_perf_xa) = + kzalloc(sizeof(*res_xa), GFP_KERNEL); + struct access_coordinate coords[ACCESS_COORDINATE_MAX]; + struct cxl_perf_ctx *ctx, *us_ctx; + unsigned long index, us_index; + int dev_count = 0; + int gp_count = 0; + void *ptr; + int rc; + + if (!res_xa) + return ERR_PTR(-ENOMEM); + xa_init(res_xa); + + xa_for_each(input_xa, index, ctx) { + struct device *dev = (struct device *)index; + struct cxl_port *port = ctx->port; + struct cxl_port *parent_port = to_cxl_port(port->dev.parent); + struct cxl_port *gp_port = to_cxl_port(parent_port->dev.parent); + struct cxl_dport *dport = port->parent_dport; + bool is_root = false; + + dev_count++; + if (is_cxl_root(gp_port)) { + is_root = true; + gp_count++; + } + + /* + * If the grandparent is cxl root, then index is the root port, + * otherwise it's the parent switch upstream device. + */ + if (is_root) + us_index = (unsigned long)port->parent_dport->dport_dev; + else + us_index = (unsigned long)parent_port->uport_dev; + + us_ctx = xa_load(res_xa, us_index); + if (!us_ctx) { + struct cxl_perf_ctx *n __free(kfree) = + kzalloc(sizeof(*n), GFP_KERNEL); + + if (!n) + return ERR_PTR(-ENOMEM); + + ptr = xa_store(res_xa, us_index, n, GFP_KERNEL); + if (xa_is_err(ptr)) + return ERR_PTR(xa_err(ptr)); + us_ctx = no_free_ptr(n); + us_ctx->port = parent_port; + } + + /* + * If the device isn't an upstream PCIe port, there's something + * wrong with the topology. + */ + if (!dev_is_pci(dev)) + return ERR_PTR(-EINVAL); + + /* Retrieve the upstream link bandwidth */ + rc = cxl_pci_get_bandwidth(to_pci_dev(dev), coords); + if (rc) + return ERR_PTR(-ENXIO); + + /* + * Take the min of downstream bandwidth and the upstream link + * bandwidth. + */ + cxl_coordinates_combine(coords, coords, ctx->coord); + + /* + * Take the min of the calculated bandwdith and the upstream + * switch SSLBIS bandwidth if there's a parent switch + */ + if (!is_root) + cxl_coordinates_combine(coords, coords, dport->coord); + + /* + * Aggregate the calculated bandwidth common to an upstream + * switch. + */ + cxl_bandwidth_add(us_ctx->coord, us_ctx->coord, coords); + } + + /* Asymmetric topology detected. */ + if (gp_count) { + if (gp_count != dev_count) { + dev_dbg(&cxlr->dev, + "Asymmetric hierarchy detected, bandwidth not updated\n"); + return ERR_PTR(-EOPNOTSUPP); + } + *gp_is_root = true; + } + + return no_free_ptr(res_xa); +} + +/** + * cxl_rp_gather_bandwidth - handle the root port level bandwidth collection + * @xa: the xarray that holds the cxl_perf_ctx that has the bandwidth calculated + * below each root port device. + * + * Return: xarray that holds cxl_perf_ctx per host bridge or ERR_PTR(-errno) + */ +static struct xarray *cxl_rp_gather_bandwidth(struct xarray *xa) +{ + struct xarray *hb_xa __free(free_perf_xa) = + kzalloc(sizeof(*hb_xa), GFP_KERNEL); + struct cxl_perf_ctx *ctx; + unsigned long index; + + if (!hb_xa) + return ERR_PTR(-ENOMEM); + xa_init(hb_xa); + + xa_for_each(xa, index, ctx) { + struct cxl_port *port = ctx->port; + unsigned long hb_index = (unsigned long)port->uport_dev; + struct cxl_perf_ctx *hb_ctx; + void *ptr; + + hb_ctx = xa_load(hb_xa, hb_index); + if (!hb_ctx) { + struct cxl_perf_ctx *n __free(kfree) = + kzalloc(sizeof(*n), GFP_KERNEL); + + if (!n) + return ERR_PTR(-ENOMEM); + ptr = xa_store(hb_xa, hb_index, n, GFP_KERNEL); + if (xa_is_err(ptr)) + return ERR_PTR(xa_err(ptr)); + hb_ctx = no_free_ptr(n); + hb_ctx->port = port; + } + + cxl_bandwidth_add(hb_ctx->coord, hb_ctx->coord, ctx->coord); + } + + return no_free_ptr(hb_xa); +} + +/** + * cxl_hb_gather_bandwidth - handle the host bridge level bandwidth collection + * @xa: the xarray that holds the cxl_perf_ctx that has the bandwidth calculated + * below each host bridge. + * + * Return: xarray that holds cxl_perf_ctx per ACPI0017 device or ERR_PTR(-errno) + */ +static struct xarray *cxl_hb_gather_bandwidth(struct xarray *xa) +{ + struct xarray *mw_xa __free(free_perf_xa) = + kzalloc(sizeof(*mw_xa), GFP_KERNEL); + struct cxl_perf_ctx *ctx; + unsigned long index; + + if (!mw_xa) + return ERR_PTR(-ENOMEM); + xa_init(mw_xa); + + xa_for_each(xa, index, ctx) { + struct cxl_port *port = ctx->port; + struct cxl_port *parent_port; + struct cxl_perf_ctx *mw_ctx; + struct cxl_dport *dport; + unsigned long mw_index; + void *ptr; + + parent_port = to_cxl_port(port->dev.parent); + mw_index = (unsigned long)parent_port->uport_dev; + + mw_ctx = xa_load(mw_xa, mw_index); + if (!mw_ctx) { + struct cxl_perf_ctx *n __free(kfree) = + kzalloc(sizeof(*n), GFP_KERNEL); + + if (!n) + return ERR_PTR(-ENOMEM); + ptr = xa_store(mw_xa, mw_index, n, GFP_KERNEL); + if (xa_is_err(ptr)) + return ERR_PTR(xa_err(ptr)); + mw_ctx = no_free_ptr(n); + } + + dport = port->parent_dport; + cxl_coordinates_combine(ctx->coord, ctx->coord, dport->coord); + cxl_bandwidth_add(mw_ctx->coord, mw_ctx->coord, ctx->coord); + } + + return no_free_ptr(mw_xa); +} + +/** + * cxl_region_update_bandwidth - Update the bandwidth access coordinates of a region + * @cxlr: The region being operated on + * @input_xa: xarray holds cxl_perf_ctx wht calculated bandwidth per ACPI0017 instance + */ +static void cxl_region_update_bandwidth(struct cxl_region *cxlr, + struct xarray *input_xa) +{ + struct access_coordinate coord[ACCESS_COORDINATE_MAX]; + struct cxl_perf_ctx *ctx; + unsigned long index; + + memset(coord, 0, sizeof(coord)); + xa_for_each(input_xa, index, ctx) + cxl_bandwidth_add(coord, coord, ctx->coord); + + for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { + cxlr->coord[i].read_bandwidth = coord[i].read_bandwidth; + cxlr->coord[i].write_bandwidth = coord[i].write_bandwidth; + } +} + +/** + * cxl_region_shared_upstream_bandwidth_update - Recalculate the bandwidth for + * the region + * @cxlr: the cxl region to recalculate + * + * The function walks the topology from bottom up and calculates the bandwidth. It + * starts at the endpoints, processes at the switches if any, processes at the rootport + * level, at the host bridge level, and finally aggregates at the region. + */ +void cxl_region_shared_upstream_bandwidth_update(struct cxl_region *cxlr) +{ + struct xarray *working_xa; + int root_count = 0; + bool is_root; + int rc; + + lockdep_assert_held(&cxl_dpa_rwsem); + + struct xarray *usp_xa __free(free_perf_xa) = + kzalloc(sizeof(*usp_xa), GFP_KERNEL); + + if (!usp_xa) return; + + xa_init(usp_xa); + + /* Collect bandwidth data from all the endpoints. */ + for (int i = 0; i < cxlr->params.nr_targets; i++) { + struct cxl_endpoint_decoder *cxled = cxlr->params.targets[i]; + + is_root = false; + rc = cxl_endpoint_gather_bandwidth(cxlr, cxled, usp_xa, &is_root); + if (rc) + return; + root_count += is_root; } + /* Detect asymmetric hierarchy with some direct attached endpoints. */ + if (root_count && root_count != cxlr->params.nr_targets) { + dev_dbg(&cxlr->dev, + "Asymmetric hierarchy detected, bandwidth not updated\n"); + return; + } + + /* + * Walk up one or more switches to deal with the bandwidth of the + * switches if they exist. Endpoints directly attached to RPs skip + * over this part. + */ + if (!root_count) { + do { + working_xa = cxl_switch_gather_bandwidth(cxlr, usp_xa, + &is_root); + if (IS_ERR(working_xa)) + return; + free_perf_xa(usp_xa); + usp_xa = working_xa; + } while (!is_root); + } + + /* Handle the bandwidth at the root port of the hierarchy */ + working_xa = cxl_rp_gather_bandwidth(usp_xa); + if (IS_ERR(working_xa)) + return; + free_perf_xa(usp_xa); + usp_xa = working_xa; + + /* Handle the bandwidth at the host bridge of the hierarchy */ + working_xa = cxl_hb_gather_bandwidth(usp_xa); + if (IS_ERR(working_xa)) + return; + free_perf_xa(usp_xa); + usp_xa = working_xa; + + /* + * Aggregate all the bandwidth collected per CFMWS (ACPI0017) and + * update the region bandwidth with the final calculated values. + */ + cxl_region_update_bandwidth(cxlr, usp_xa); +} + +void cxl_region_perf_data_calculate(struct cxl_region *cxlr, + struct cxl_endpoint_decoder *cxled) +{ + struct cxl_dpa_perf *perf; + lockdep_assert_held(&cxl_dpa_rwsem); - if (!range_contains(&perf->dpa_range, &dpa)) + perf = cxled_get_dpa_perf(cxled, cxlr->mode); + if (IS_ERR(perf)) return; for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h index 72a506c9dbd0..0c62b4069ba0 100644 --- a/drivers/cxl/core/core.h +++ b/drivers/cxl/core/core.h @@ -103,9 +103,11 @@ enum cxl_poison_trace_type { }; long cxl_pci_get_latency(struct pci_dev *pdev); - +int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c); int cxl_update_hmat_access_coordinates(int nid, struct cxl_region *cxlr, enum access_coordinate_class access); bool cxl_need_node_perf_attrs_update(int nid); +int cxl_port_get_switch_dport_bandwidth(struct cxl_port *port, + struct access_coordinate *c); #endif /* __CXL_CORE_H__ */ diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 9d396ef0aeed..5b46bc46aaa9 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -1031,3 +1031,26 @@ bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port) __cxl_endpoint_decoder_reset_detected); } EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_reset_detected, CXL); + +int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c) +{ + int speed, bw; + u16 lnksta; + u32 width; + + speed = pcie_link_speed_mbps(pdev); + if (speed < 0) + return speed; + speed /= BITS_PER_BYTE; + + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnksta); + width = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta); + bw = speed * width; + + for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { + c[i].read_bandwidth = bw; + c[i].write_bandwidth = bw; + } + + return 0; +} diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index a5e6f3d23cfb..e666ec6a9085 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -2237,6 +2237,26 @@ int cxl_endpoint_get_perf_coordinates(struct cxl_port *port, } EXPORT_SYMBOL_NS_GPL(cxl_endpoint_get_perf_coordinates, CXL); +int cxl_port_get_switch_dport_bandwidth(struct cxl_port *port, + struct access_coordinate *c) +{ + struct cxl_dport *dport = port->parent_dport; + + /* Check this port is connected to a switch DSP and not an RP */ + if (parent_port_is_cxl_root(to_cxl_port(port->dev.parent))) + return -ENODEV; + + if (!coordinates_valid(dport->coord)) + return -EINVAL; + + for (int i = 0; i < ACCESS_COORDINATE_MAX; i++) { + c[i].read_bandwidth = dport->coord[i].read_bandwidth; + c[i].write_bandwidth = dport->coord[i].write_bandwidth; + } + + return 0; +} + /* for user tooling to ensure port disable work has completed */ static ssize_t flush_store(const struct bus_type *bus, const char *buf, size_t count) { diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index 7bb79f3f318c..e701e4b04032 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -1983,6 +1983,7 @@ static int cxl_region_attach(struct cxl_region *cxlr, * then the region is already committed. */ p->state = CXL_CONFIG_COMMIT; + cxl_region_shared_upstream_bandwidth_update(cxlr); return 0; } @@ -2004,6 +2005,7 @@ static int cxl_region_attach(struct cxl_region *cxlr, if (rc) return rc; p->state = CXL_CONFIG_ACTIVE; + cxl_region_shared_upstream_bandwidth_update(cxlr); } cxled->cxld.interleave_ways = p->interleave_ways; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 0fc96f8bf15c..0d8b810a51f0 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -891,6 +891,7 @@ int cxl_endpoint_get_perf_coordinates(struct cxl_port *port, struct access_coordinate *coord); void cxl_region_perf_data_calculate(struct cxl_region *cxlr, struct cxl_endpoint_decoder *cxled); +void cxl_region_shared_upstream_bandwidth_update(struct cxl_region *cxlr); void cxl_memdev_update_perf(struct cxl_memdev *cxlmd); |