diff options
| -rw-r--r-- | hdata/spira.c | 9 | ||||
| -rw-r--r-- | platforms/ibm-fsp/zz.c | 96 |
2 files changed, 103 insertions, 2 deletions
diff --git a/hdata/spira.c b/hdata/spira.c index 3d7e21c..a23fd17 100644 --- a/hdata/spira.c +++ b/hdata/spira.c @@ -1369,7 +1369,14 @@ static void add_npu(struct dt_node *xscom, const struct HDIF_array_hdr *links, uint64_t speed = 0, nvlink_speed = 0; struct dt_node *node; - /* only add a link node if this link is targeted at at device */ + /* + * Only add a link node if this link is targeted at a + * GPU device. + * + * If we ever activate it for an opencapi device, we + * should revisit the link definitions hard-coded + * on ZZ. + */ if (be32_to_cpu(link->usage) != SMP_LINK_USE_GPU) continue; diff --git a/platforms/ibm-fsp/zz.c b/platforms/ibm-fsp/zz.c index e369f8d..bbeaf29 100644 --- a/platforms/ibm-fsp/zz.c +++ b/platforms/ibm-fsp/zz.c @@ -45,6 +45,97 @@ static const struct platform_ocapi zz_ocapi = { .odl_phy_swap = true, }; +#define NPU_BASE 0x5011000 +#define NPU_SIZE 0x2c +#define NPU_INDIRECT0 0x8000000009010c3f /* OB0 - no OB3 on ZZ */ + +static void create_link(struct dt_node *npu, int group, int index) +{ + struct dt_node *link; + uint32_t lane_mask; + + switch (index) { + case 2: + lane_mask = 0xf1e000; /* 0-3, 7-10 */ + break; + case 3: + lane_mask = 0x00078f; /* 13-16, 20-23 */ + break; + default: + assert(0); + } + + link = dt_new_addr(npu, "link", index); + dt_add_property_string(link, "compatible", "ibm,npu-link"); + dt_add_property_cells(link, "ibm,npu-link-index", index); + dt_add_property_u64s(link, "ibm,npu-phy", NPU_INDIRECT0); + dt_add_property_cells(link, "ibm,npu-lane-mask", lane_mask); + dt_add_property_cells(link, "ibm,npu-group-id", group); + dt_add_property_u64s(link, "ibm,link-speed", 25000000000ul); +} + +static void add_opencapi_dt_nodes(void) +{ + struct dt_node *npu, *xscom; + int npu_index = 0; + int phb_index = 7; + + /* + * In an ideal world, we should get all the NPU links + * information from HDAT. But after some effort, HDAT is still + * giving incorrect information for opencapi. As of this + * writing: + * 1. link usage is wrong for most FPGA cards (0xFFFF vs. 2) + * 2. the 24-bit lane mask is aligned differently than on + * other platforms (witherspoon) + * 3. connecting a link entry in HDAT to the real physical + * link will need extra work: + * - HDAT does presence detection and only lists links with + * an adapter, so we cannot use default ordering like on + * witherspoon + * - best option is probably the brick ID field (offset 8). + * It's coming straight from the MRW, but seems to match + * what we expect (2 or 3). Would need to be checked. + * + * To make things more fun, any change in the HDAT data needs + * to be coordinated with PHYP, which is using (some of) those + * fields. + * + * As a consequence: + * 1. the hdat parsing code in skiboot remains disabled (for + * opencapi) + * 2. we hard-code the NPU and links entries in the device + * tree. + * + * Getting the data from HDAT would have the advantage of + * providing the real link speed (20.0 vs. 25.78125 gbps), + * which is useful as there's one speed-dependent setting we + * need to do when initializing the NPU. Our hard coded + * definition assumes the higher speed and may need tuning in + * debug scenario using a lower link speed. + */ + dt_for_each_compatible(dt_root, xscom, "ibm,xscom") { + /* + * our hdat parsing code may create NPU nodes with no + * links, so let's make sure we start from a clean + * state + */ + npu = dt_find_by_name_addr(xscom, "npu", NPU_BASE); + if (npu) + dt_free(npu); + + npu = dt_new_addr(xscom, "npu", NPU_BASE); + dt_add_property_cells(npu, "reg", NPU_BASE, NPU_SIZE); + dt_add_property_strings(npu, "compatible", "ibm,power9-npu"); + dt_add_property_cells(npu, "ibm,npu-index", npu_index++); + dt_add_property_cells(npu, "ibm,phb-index", phb_index++); + dt_add_property_cells(npu, "ibm,npu-links", 2); + + create_link(npu, 1, 2); + create_link(npu, 2, 3); + } +} + static bool zz_probe(void) { /* FIXME: make this neater when the dust settles */ @@ -54,8 +145,11 @@ static bool zz_probe(void) dt_node_is_compatible(dt_root, "ibm,zz-2s4u") || dt_node_is_compatible(dt_root, "ibm,zz-1s4u+gen4") || dt_node_is_compatible(dt_root, "ibm,zz-2s2u+gen4") || - dt_node_is_compatible(dt_root, "ibm,zz-2s4u+gen4")) + dt_node_is_compatible(dt_root, "ibm,zz-2s4u+gen4")) { + + add_opencapi_dt_nodes(); return true; + } return false; } |