diff options
Diffstat (limited to 'rr-cache/dc9e44dc2a9a9048f77095c80cecebb18bac9898/postimage.1')
| -rw-r--r-- | rr-cache/dc9e44dc2a9a9048f77095c80cecebb18bac9898/postimage.1 | 1845 |
1 files changed, 1845 insertions, 0 deletions
diff --git a/rr-cache/dc9e44dc2a9a9048f77095c80cecebb18bac9898/postimage.1 b/rr-cache/dc9e44dc2a9a9048f77095c80cecebb18bac9898/postimage.1 new file mode 100644 index 000000000000..550eeed43903 --- /dev/null +++ b/rr-cache/dc9e44dc2a9a9048f77095c80cecebb18bac9898/postimage.1 @@ -0,0 +1,1845 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2022 Intel Corporation + */ + +#include "xe_guc_ct.h" + +#include <linux/bitfield.h> +#include <linux/circ_buf.h> +#include <linux/delay.h> +#include <linux/fault-inject.h> + +#include <kunit/static_stub.h> + +#include <drm/drm_managed.h> + +#include "abi/guc_actions_abi.h" +#include "abi/guc_actions_sriov_abi.h" +#include "abi/guc_klvs_abi.h" +#include "xe_bo.h" +#include "xe_devcoredump.h" +#include "xe_device.h" +#include "xe_gt.h" +#include "xe_gt_pagefault.h" +#include "xe_gt_printk.h" +#include "xe_gt_sriov_pf_control.h" +#include "xe_gt_sriov_pf_monitor.h" +#include "xe_gt_tlb_invalidation.h" +#include "xe_guc.h" +#include "xe_guc_log.h" +#include "xe_guc_relay.h" +#include "xe_guc_submit.h" +#include "xe_map.h" +#include "xe_pm.h" +#include "xe_trace_guc.h" + +#if IS_ENABLED(CONFIG_DRM_XE_DEBUG) +enum { + /* Internal states, not error conditions */ + CT_DEAD_STATE_REARM, /* 0x0001 */ + CT_DEAD_STATE_CAPTURE, /* 0x0002 */ + + /* Error conditions */ + CT_DEAD_SETUP, /* 0x0004 */ + CT_DEAD_H2G_WRITE, /* 0x0008 */ + CT_DEAD_H2G_HAS_ROOM, /* 0x0010 */ + CT_DEAD_G2H_READ, /* 0x0020 */ + CT_DEAD_G2H_RECV, /* 0x0040 */ + CT_DEAD_G2H_RELEASE, /* 0x0080 */ + CT_DEAD_DEADLOCK, /* 0x0100 */ + CT_DEAD_PROCESS_FAILED, /* 0x0200 */ + CT_DEAD_FAST_G2H, /* 0x0400 */ + CT_DEAD_PARSE_G2H_RESPONSE, /* 0x0800 */ + CT_DEAD_PARSE_G2H_UNKNOWN, /* 0x1000 */ + CT_DEAD_PARSE_G2H_ORIGIN, /* 0x2000 */ + CT_DEAD_PARSE_G2H_TYPE, /* 0x4000 */ +}; + +static void ct_dead_worker_func(struct work_struct *w); +static void ct_dead_capture(struct xe_guc_ct *ct, struct guc_ctb *ctb, u32 reason_code); + +#define CT_DEAD(ct, ctb, reason_code) ct_dead_capture((ct), (ctb), CT_DEAD_##reason_code) +#else +#define CT_DEAD(ct, ctb, reason) \ + do { \ + struct guc_ctb *_ctb = (ctb); \ + if (_ctb) \ + _ctb->info.broken = true; \ + } while (0) +#endif + +/* Used when a CT send wants to block and / or receive data */ +struct g2h_fence { + u32 *response_buffer; + u32 seqno; + u32 response_data; + u16 response_len; + u16 error; + u16 hint; + u16 reason; + bool retry; + bool fail; + bool done; +}; + +static void g2h_fence_init(struct g2h_fence *g2h_fence, u32 *response_buffer) +{ + g2h_fence->response_buffer = response_buffer; + g2h_fence->response_data = 0; + g2h_fence->response_len = 0; + g2h_fence->fail = false; + g2h_fence->retry = false; + g2h_fence->done = false; + g2h_fence->seqno = ~0x0; +} + +static bool g2h_fence_needs_alloc(struct g2h_fence *g2h_fence) +{ + return g2h_fence->seqno == ~0x0; +} + +static struct xe_guc * +ct_to_guc(struct xe_guc_ct *ct) +{ + return container_of(ct, struct xe_guc, ct); +} + +static struct xe_gt * +ct_to_gt(struct xe_guc_ct *ct) +{ + return container_of(ct, struct xe_gt, uc.guc.ct); +} + +static struct xe_device * +ct_to_xe(struct xe_guc_ct *ct) +{ + return gt_to_xe(ct_to_gt(ct)); +} + +/** + * DOC: GuC CTB Blob + * + * We allocate single blob to hold both CTB descriptors and buffers: + * + * +--------+-----------------------------------------------+------+ + * | offset | contents | size | + * +========+===============================================+======+ + * | 0x0000 | H2G CTB Descriptor (send) | | + * +--------+-----------------------------------------------+ 4K | + * | 0x0800 | G2H CTB Descriptor (g2h) | | + * +--------+-----------------------------------------------+------+ + * | 0x1000 | H2G CT Buffer (send) | n*4K | + * | | | | + * +--------+-----------------------------------------------+------+ + * | 0x1000 | G2H CT Buffer (g2h) | m*4K | + * | + n*4K | | | + * +--------+-----------------------------------------------+------+ + * + * Size of each ``CT Buffer`` must be multiple of 4K. + * We don't expect too many messages in flight at any time, unless we are + * using the GuC submission. In that case each request requires a minimum + * 2 dwords which gives us a maximum 256 queue'd requests. Hopefully this + * enough space to avoid backpressure on the driver. We increase the size + * of the receive buffer (relative to the send) to ensure a G2H response + * CTB has a landing spot. + * + * In addition to submissions, the G2H buffer needs to be able to hold + * enough space for recoverable page fault notifications. The number of + * page faults is interrupt driven and can be as much as the number of + * compute resources available. However, most of the actual work for these + * is in a separate page fault worker thread. Therefore we only need to + * make sure the queue has enough space to handle all of the submissions + * and responses and an extra buffer for incoming page faults. + */ + +#define CTB_DESC_SIZE ALIGN(sizeof(struct guc_ct_buffer_desc), SZ_2K) +#define CTB_H2G_BUFFER_SIZE (SZ_4K) +#define CTB_G2H_BUFFER_SIZE (SZ_128K) +#define G2H_ROOM_BUFFER_SIZE (CTB_G2H_BUFFER_SIZE / 2) + +/** + * xe_guc_ct_queue_proc_time_jiffies - Return maximum time to process a full + * CT command queue + * @ct: the &xe_guc_ct. Unused at this moment but will be used in the future. + * + * Observation is that a 4KiB buffer full of commands takes a little over a + * second to process. Use that to calculate maximum time to process a full CT + * command queue. + * + * Return: Maximum time to process a full CT queue in jiffies. + */ +long xe_guc_ct_queue_proc_time_jiffies(struct xe_guc_ct *ct) +{ + BUILD_BUG_ON(!IS_ALIGNED(CTB_H2G_BUFFER_SIZE, SZ_4)); + return (CTB_H2G_BUFFER_SIZE / SZ_4K) * HZ; +} + +static size_t guc_ct_size(void) +{ + return 2 * CTB_DESC_SIZE + CTB_H2G_BUFFER_SIZE + + CTB_G2H_BUFFER_SIZE; +} + +static void guc_ct_fini(struct drm_device *drm, void *arg) +{ + struct xe_guc_ct *ct = arg; + + destroy_workqueue(ct->g2h_wq); + xa_destroy(&ct->fence_lookup); +} + +static void receive_g2h(struct xe_guc_ct *ct); +static void g2h_worker_func(struct work_struct *w); +static void safe_mode_worker_func(struct work_struct *w); + +static void primelockdep(struct xe_guc_ct *ct) +{ + if (!IS_ENABLED(CONFIG_LOCKDEP)) + return; + + fs_reclaim_acquire(GFP_KERNEL); + might_lock(&ct->lock); + fs_reclaim_release(GFP_KERNEL); +} + +int xe_guc_ct_init(struct xe_guc_ct *ct) +{ + struct xe_device *xe = ct_to_xe(ct); + struct xe_gt *gt = ct_to_gt(ct); + struct xe_tile *tile = gt_to_tile(gt); + struct xe_bo *bo; + int err; + + xe_gt_assert(gt, !(guc_ct_size() % PAGE_SIZE)); + + ct->g2h_wq = alloc_ordered_workqueue("xe-g2h-wq", WQ_MEM_RECLAIM); + if (!ct->g2h_wq) + return -ENOMEM; + + spin_lock_init(&ct->fast_lock); + xa_init(&ct->fence_lookup); + INIT_WORK(&ct->g2h_worker, g2h_worker_func); + INIT_DELAYED_WORK(&ct->safe_mode_worker, safe_mode_worker_func); +#if IS_ENABLED(CONFIG_DRM_XE_DEBUG) + spin_lock_init(&ct->dead.lock); + INIT_WORK(&ct->dead.worker, ct_dead_worker_func); +#endif + init_waitqueue_head(&ct->wq); + init_waitqueue_head(&ct->g2h_fence_wq); + + err = drmm_mutex_init(&xe->drm, &ct->lock); + if (err) + return err; + + primelockdep(ct); + + bo = xe_managed_bo_create_pin_map(xe, tile, guc_ct_size(), + XE_BO_FLAG_SYSTEM | + XE_BO_FLAG_GGTT | + XE_BO_FLAG_GGTT_INVALIDATE); + if (IS_ERR(bo)) + return PTR_ERR(bo); + + ct->bo = bo; + + err = drmm_add_action_or_reset(&xe->drm, guc_ct_fini, ct); + if (err) + return err; + + xe_gt_assert(gt, ct->state == XE_GUC_CT_STATE_NOT_INITIALIZED); + ct->state = XE_GUC_CT_STATE_DISABLED; + return 0; +} +ALLOW_ERROR_INJECTION(xe_guc_ct_init, ERRNO); /* See xe_pci_probe() */ + +#define desc_read(xe_, guc_ctb__, field_) \ + xe_map_rd_field(xe_, &guc_ctb__->desc, 0, \ + struct guc_ct_buffer_desc, field_) + +#define desc_write(xe_, guc_ctb__, field_, val_) \ + xe_map_wr_field(xe_, &guc_ctb__->desc, 0, \ + struct guc_ct_buffer_desc, field_, val_) + +static void guc_ct_ctb_h2g_init(struct xe_device *xe, struct guc_ctb *h2g, + struct iosys_map *map) +{ + h2g->info.size = CTB_H2G_BUFFER_SIZE / sizeof(u32); + h2g->info.resv_space = 0; + h2g->info.tail = 0; + h2g->info.head = 0; + h2g->info.space = CIRC_SPACE(h2g->info.tail, h2g->info.head, + h2g->info.size) - + h2g->info.resv_space; + h2g->info.broken = false; + + h2g->desc = *map; + xe_map_memset(xe, &h2g->desc, 0, 0, sizeof(struct guc_ct_buffer_desc)); + + h2g->cmds = IOSYS_MAP_INIT_OFFSET(map, CTB_DESC_SIZE * 2); +} + +static void guc_ct_ctb_g2h_init(struct xe_device *xe, struct guc_ctb *g2h, + struct iosys_map *map) +{ + g2h->info.size = CTB_G2H_BUFFER_SIZE / sizeof(u32); + g2h->info.resv_space = G2H_ROOM_BUFFER_SIZE / sizeof(u32); + g2h->info.head = 0; + g2h->info.tail = 0; + g2h->info.space = CIRC_SPACE(g2h->info.tail, g2h->info.head, + g2h->info.size) - + g2h->info.resv_space; + g2h->info.broken = false; + + g2h->desc = IOSYS_MAP_INIT_OFFSET(map, CTB_DESC_SIZE); + xe_map_memset(xe, &g2h->desc, 0, 0, sizeof(struct guc_ct_buffer_desc)); + + g2h->cmds = IOSYS_MAP_INIT_OFFSET(map, CTB_DESC_SIZE * 2 + + CTB_H2G_BUFFER_SIZE); +} + +static int guc_ct_ctb_h2g_register(struct xe_guc_ct *ct) +{ + struct xe_guc *guc = ct_to_guc(ct); + u32 desc_addr, ctb_addr, size; + int err; + + desc_addr = xe_bo_ggtt_addr(ct->bo); + ctb_addr = xe_bo_ggtt_addr(ct->bo) + CTB_DESC_SIZE * 2; + size = ct->ctbs.h2g.info.size * sizeof(u32); + + err = xe_guc_self_cfg64(guc, + GUC_KLV_SELF_CFG_H2G_CTB_DESCRIPTOR_ADDR_KEY, + desc_addr); + if (err) + return err; + + err = xe_guc_self_cfg64(guc, + GUC_KLV_SELF_CFG_H2G_CTB_ADDR_KEY, + ctb_addr); + if (err) + return err; + + return xe_guc_self_cfg32(guc, + GUC_KLV_SELF_CFG_H2G_CTB_SIZE_KEY, + size); +} + +static int guc_ct_ctb_g2h_register(struct xe_guc_ct *ct) +{ + struct xe_guc *guc = ct_to_guc(ct); + u32 desc_addr, ctb_addr, size; + int err; + + desc_addr = xe_bo_ggtt_addr(ct->bo) + CTB_DESC_SIZE; + ctb_addr = xe_bo_ggtt_addr(ct->bo) + CTB_DESC_SIZE * 2 + + CTB_H2G_BUFFER_SIZE; + size = ct->ctbs.g2h.info.size * sizeof(u32); + + err = xe_guc_self_cfg64(guc, + GUC_KLV_SELF_CFG_G2H_CTB_DESCRIPTOR_ADDR_KEY, + desc_addr); + if (err) + return err; + + err = xe_guc_self_cfg64(guc, + GUC_KLV_SELF_CFG_G2H_CTB_ADDR_KEY, + ctb_addr); + if (err) + return err; + + return xe_guc_self_cfg32(guc, + GUC_KLV_SELF_CFG_G2H_CTB_SIZE_KEY, + size); +} + +static int guc_ct_control_toggle(struct xe_guc_ct *ct, bool enable) +{ + u32 request[HOST2GUC_CONTROL_CTB_REQUEST_MSG_LEN] = { + FIELD_PREP(GUC_HXG_MSG_0_ORIGIN, GUC_HXG_ORIGIN_HOST) | + FIELD_PREP(GUC_HXG_MSG_0_TYPE, GUC_HXG_TYPE_REQUEST) | + FIELD_PREP(GUC_HXG_REQUEST_MSG_0_ACTION, + GUC_ACTION_HOST2GUC_CONTROL_CTB), + FIELD_PREP(HOST2GUC_CONTROL_CTB_REQUEST_MSG_1_CONTROL, + enable ? GUC_CTB_CONTROL_ENABLE : + GUC_CTB_CONTROL_DISABLE), + }; + int ret = xe_guc_mmio_send(ct_to_guc(ct), request, ARRAY_SIZE(request)); + + return ret > 0 ? -EPROTO : ret; +} + +static void xe_guc_ct_set_state(struct xe_guc_ct *ct, + enum xe_guc_ct_state state) +{ + mutex_lock(&ct->lock); /* Serialise dequeue_one_g2h() */ + spin_lock_irq(&ct->fast_lock); /* Serialise CT fast-path */ + + xe_gt_assert(ct_to_gt(ct), ct->g2h_outstanding == 0 || + state == XE_GUC_CT_STATE_STOPPED); + + if (ct->g2h_outstanding) + xe_pm_runtime_put(ct_to_xe(ct)); + ct->g2h_outstanding = 0; + ct->state = state; + + spin_unlock_irq(&ct->fast_lock); + + /* + * Lockdep doesn't like this under the fast lock and he destroy only + * needs to be serialized with the send path which ct lock provides. + */ + xa_destroy(&ct->fence_lookup); + + mutex_unlock(&ct->lock); +} + +static bool ct_needs_safe_mode(struct xe_guc_ct *ct) +{ + return !pci_dev_msi_enabled(to_pci_dev(ct_to_xe(ct)->drm.dev)); +} + +static bool ct_restart_safe_mode_worker(struct xe_guc_ct *ct) +{ + if (!ct_needs_safe_mode(ct)) + return false; + + queue_delayed_work(ct->g2h_wq, &ct->safe_mode_worker, HZ / 10); + return true; +} + +static void safe_mode_worker_func(struct work_struct *w) +{ + struct xe_guc_ct *ct = container_of(w, struct xe_guc_ct, safe_mode_worker.work); + + receive_g2h(ct); + + if (!ct_restart_safe_mode_worker(ct)) + xe_gt_dbg(ct_to_gt(ct), "GuC CT safe-mode canceled\n"); +} + +static void ct_enter_safe_mode(struct xe_guc_ct *ct) +{ + if (ct_restart_safe_mode_worker(ct)) + xe_gt_dbg(ct_to_gt(ct), "GuC CT safe-mode enabled\n"); +} + +static void ct_exit_safe_mode(struct xe_guc_ct *ct) +{ + if (cancel_delayed_work_sync(&ct->safe_mode_worker)) + xe_gt_dbg(ct_to_gt(ct), "GuC CT safe-mode disabled\n"); +} + +int xe_guc_ct_enable(struct xe_guc_ct *ct) +{ + struct xe_device *xe = ct_to_xe(ct); + struct xe_gt *gt = ct_to_gt(ct); + int err; + + xe_gt_assert(gt, !xe_guc_ct_enabled(ct)); + + xe_map_memset(xe, &ct->bo->vmap, 0, 0, ct->bo->size); + guc_ct_ctb_h2g_init(xe, &ct->ctbs.h2g, &ct->bo->vmap); + guc_ct_ctb_g2h_init(xe, &ct->ctbs.g2h, &ct->bo->vmap); + + err = guc_ct_ctb_h2g_register(ct); + if (err) + goto err_out; + + err = guc_ct_ctb_g2h_register(ct); + if (err) + goto err_out; + + err = guc_ct_control_toggle(ct, true); + if (err) + goto err_out; + + xe_guc_ct_set_state(ct, XE_GUC_CT_STATE_ENABLED); + + smp_mb(); + wake_up_all(&ct->wq); + xe_gt_dbg(gt, "GuC CT communication channel enabled\n"); + + if (ct_needs_safe_mode(ct)) + ct_enter_safe_mode(ct); + +#if IS_ENABLED(CONFIG_DRM_XE_DEBUG) + /* + * The CT has now been reset so the dumper can be re-armed + * after any existing dead state has been dumped. + */ + spin_lock_irq(&ct->dead.lock); + if (ct->dead.reason) + ct->dead.reason |= (1 << CT_DEAD_STATE_REARM); + spin_unlock_irq(&ct->dead.lock); +#endif + + return 0; + +err_out: + xe_gt_err(gt, "Failed to enable GuC CT (%pe)\n", ERR_PTR(err)); + CT_DEAD(ct, NULL, SETUP); + + return err; +} + +static void stop_g2h_handler(struct xe_guc_ct *ct) +{ + cancel_work_sync(&ct->g2h_worker); +} + +/** + * xe_guc_ct_disable - Set GuC to disabled state + * @ct: the &xe_guc_ct + * + * Set GuC CT to disabled state and stop g2h handler. No outstanding g2h expected + * in this transition. + */ +void xe_guc_ct_disable(struct xe_guc_ct *ct) +{ + xe_guc_ct_set_state(ct, XE_GUC_CT_STATE_DISABLED); + ct_exit_safe_mode(ct); + stop_g2h_handler(ct); +} + +/** + * xe_guc_ct_stop - Set GuC to stopped state + * @ct: the &xe_guc_ct + * + * Set GuC CT to stopped state, stop g2h handler, and clear any outstanding g2h + */ +void xe_guc_ct_stop(struct xe_guc_ct *ct) +{ + xe_guc_ct_set_state(ct, XE_GUC_CT_STATE_STOPPED); + stop_g2h_handler(ct); +} + +static bool h2g_has_room(struct xe_guc_ct *ct, u32 cmd_len) +{ + struct guc_ctb *h2g = &ct->ctbs.h2g; + + lockdep_assert_held(&ct->lock); + + if (cmd_len > h2g->info.space) { + h2g->info.head = desc_read(ct_to_xe(ct), h2g, head); + + if (h2g->info.head > h2g->info.size) { + struct xe_device *xe = ct_to_xe(ct); + u32 desc_status = desc_read(xe, h2g, status); + + desc_write(xe, h2g, status, desc_status | GUC_CTB_STATUS_OVERFLOW); + + xe_gt_err(ct_to_gt(ct), "CT: invalid head offset %u >= %u)\n", + h2g->info.head, h2g->info.size); + CT_DEAD(ct, h2g, H2G_HAS_ROOM); + return false; + } + + h2g->info.space = CIRC_SPACE(h2g->info.tail, h2g->info.head, + h2g->info.size) - + h2g->info.resv_space; + if (cmd_len > h2g->info.space) + return false; + } + + return true; +} + +static bool g2h_has_room(struct xe_guc_ct *ct, u32 g2h_len) +{ + if (!g2h_len) + return true; + + lockdep_assert_held(&ct->fast_lock); + + return ct->ctbs.g2h.info.space > g2h_len; +} + +static int has_room(struct xe_guc_ct *ct, u32 cmd_len, u32 g2h_len) +{ + lockdep_assert_held(&ct->lock); + + if (!g2h_has_room(ct, g2h_len) || !h2g_has_room(ct, cmd_len)) + return -EBUSY; + + return 0; +} + +static void h2g_reserve_space(struct xe_guc_ct *ct, u32 cmd_len) +{ + lockdep_assert_held(&ct->lock); + ct->ctbs.h2g.info.space -= cmd_len; +} + +static void __g2h_reserve_space(struct xe_guc_ct *ct, u32 g2h_len, u32 num_g2h) +{ + xe_gt_assert(ct_to_gt(ct), g2h_len <= ct->ctbs.g2h.info.space); + xe_gt_assert(ct_to_gt(ct), (!g2h_len && !num_g2h) || + (g2h_len && num_g2h)); + + if (g2h_len) { + lockdep_assert_held(&ct->fast_lock); + + if (!ct->g2h_outstanding) + xe_pm_runtime_get_noresume(ct_to_xe(ct)); + + ct->ctbs.g2h.info.space -= g2h_len; + ct->g2h_outstanding += num_g2h; + } +} + +static void __g2h_release_space(struct xe_guc_ct *ct, u32 g2h_len) +{ + bool bad = false; + + lockdep_assert_held(&ct->fast_lock); + + bad = ct->ctbs.g2h.info.space + g2h_len > + ct->ctbs.g2h.info.size - ct->ctbs.g2h.info.resv_space; + bad |= !ct->g2h_outstanding; + + if (bad) { + xe_gt_err(ct_to_gt(ct), "Invalid G2H release: %d + %d vs %d - %d -> %d vs %d, outstanding = %d!\n", + ct->ctbs.g2h.info.space, g2h_len, + ct->ctbs.g2h.info.size, ct->ctbs.g2h.info.resv_space, + ct->ctbs.g2h.info.space + g2h_len, + ct->ctbs.g2h.info.size - ct->ctbs.g2h.info.resv_space, + ct->g2h_outstanding); + CT_DEAD(ct, &ct->ctbs.g2h, G2H_RELEASE); + return; + } + + ct->ctbs.g2h.info.space += g2h_len; + if (!--ct->g2h_outstanding) + xe_pm_runtime_put(ct_to_xe(ct)); +} + +static void g2h_release_space(struct xe_guc_ct *ct, u32 g2h_len) +{ + spin_lock_irq(&ct->fast_lock); + __g2h_release_space(ct, g2h_len); + spin_unlock_irq(&ct->fast_lock); +} + +#define H2G_CT_HEADERS (GUC_CTB_HDR_LEN + 1) /* one DW CTB header and one DW HxG header */ + +static int h2g_write(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 ct_fence_value, bool want_response) +{ + struct xe_device *xe = ct_to_xe(ct); + struct xe_gt *gt = ct_to_gt(ct); + struct guc_ctb *h2g = &ct->ctbs.h2g; + u32 cmd[H2G_CT_HEADERS]; + u32 tail = h2g->info.tail; + u32 full_len; + struct iosys_map map = IOSYS_MAP_INIT_OFFSET(&h2g->cmds, + tail * sizeof(u32)); + u32 desc_status; + + full_len = len + GUC_CTB_HDR_LEN; + + lockdep_assert_held(&ct->lock); + xe_gt_assert(gt, full_len <= GUC_CTB_MSG_MAX_LEN); + + desc_status = desc_read(xe, h2g, status); + if (desc_status) { + xe_gt_err(gt, "CT write: non-zero status: %u\n", desc_status); + goto corrupted; + } + + if (IS_ENABLED(CONFIG_DRM_XE_DEBUG)) { + u32 desc_tail = desc_read(xe, h2g, tail); + u32 desc_head = desc_read(xe, h2g, head); + + if (tail != desc_tail) { + desc_write(xe, h2g, status, desc_status | GUC_CTB_STATUS_MISMATCH); + xe_gt_err(gt, "CT write: tail was modified %u != %u\n", desc_tail, tail); + goto corrupted; + } + + if (tail > h2g->info.size) { + desc_write(xe, h2g, status, desc_status | GUC_CTB_STATUS_OVERFLOW); + xe_gt_err(gt, "CT write: tail out of range: %u vs %u\n", + tail, h2g->info.size); + goto corrupted; + } + + if (desc_head >= h2g->info.size) { + desc_write(xe, h2g, status, desc_status | GUC_CTB_STATUS_OVERFLOW); + xe_gt_err(gt, "CT write: invalid head offset %u >= %u)\n", + desc_head, h2g->info.size); + goto corrupted; + } + } + + /* Command will wrap, zero fill (NOPs), return and check credits again */ + if (tail + full_len > h2g->info.size) { + xe_map_memset(xe, &map, 0, 0, + (h2g->info.size - tail) * sizeof(u32)); + h2g_reserve_space(ct, (h2g->info.size - tail)); + h2g->info.tail = 0; + desc_write(xe, h2g, tail, h2g->info.tail); + + return -EAGAIN; + } + + /* + * dw0: CT header (including fence) + * dw1: HXG header (including action code) + * dw2+: action data + */ + cmd[0] = FIELD_PREP(GUC_CTB_MSG_0_FORMAT, GUC_CTB_FORMAT_HXG) | + FIELD_PREP(GUC_CTB_MSG_0_NUM_DWORDS, len) | + FIELD_PREP(GUC_CTB_MSG_0_FENCE, ct_fence_value); + if (want_response) { + cmd[1] = + FIELD_PREP(GUC_HXG_MSG_0_TYPE, GUC_HXG_TYPE_REQUEST) | + FIELD_PREP(GUC_HXG_EVENT_MSG_0_ACTION | + GUC_HXG_EVENT_MSG_0_DATA0, action[0]); + } else { + cmd[1] = + FIELD_PREP(GUC_HXG_MSG_0_TYPE, GUC_HXG_TYPE_FAST_REQUEST) | + FIELD_PREP(GUC_HXG_EVENT_MSG_0_ACTION | + GUC_HXG_EVENT_MSG_0_DATA0, action[0]); + } + + /* H2G header in cmd[1] replaces action[0] so: */ + --len; + ++action; + + /* Write H2G ensuring visable before descriptor update */ + xe_map_memcpy_to(xe, &map, 0, cmd, H2G_CT_HEADERS * sizeof(u32)); + xe_map_memcpy_to(xe, &map, H2G_CT_HEADERS * sizeof(u32), action, len * sizeof(u32)); + xe_device_wmb(xe); + + /* Update local copies */ + h2g->info.tail = (tail + full_len) % h2g->info.size; + h2g_reserve_space(ct, full_len); + + /* Update descriptor */ + desc_write(xe, h2g, tail, h2g->info.tail); + + trace_xe_guc_ctb_h2g(xe, gt->info.id, *(action - 1), full_len, + desc_read(xe, h2g, head), h2g->info.tail); + + return 0; + +corrupted: + CT_DEAD(ct, &ct->ctbs.h2g, H2G_WRITE); + return -EPIPE; +} + +/* + * The CT protocol accepts a 16 bits fence. This field is fully owned by the + * driver, the GuC will just copy it to the reply message. Since we need to + * be able to distinguish between replies to REQUEST and FAST_REQUEST messages, + * we use one bit of the seqno as an indicator for that and a rolling counter + * for the remaining 15 bits. + */ +#define CT_SEQNO_MASK GENMASK(14, 0) +#define CT_SEQNO_UNTRACKED BIT(15) +static u16 next_ct_seqno(struct xe_guc_ct *ct, bool is_g2h_fence) +{ + u32 seqno = ct->fence_seqno++ & CT_SEQNO_MASK; + + if (!is_g2h_fence) + seqno |= CT_SEQNO_UNTRACKED; + + return seqno; +} + +static int __guc_ct_send_locked(struct xe_guc_ct *ct, const u32 *action, + u32 len, u32 g2h_len, u32 num_g2h, + struct g2h_fence *g2h_fence) +{ + struct xe_gt *gt __maybe_unused = ct_to_gt(ct); + u16 seqno; + int ret; + + xe_gt_assert(gt, ct->state != XE_GUC_CT_STATE_NOT_INITIALIZED); + xe_gt_assert(gt, !g2h_len || !g2h_fence); + xe_gt_assert(gt, !num_g2h || !g2h_fence); + xe_gt_assert(gt, !g2h_len || num_g2h); + xe_gt_assert(gt, g2h_len || !num_g2h); + lockdep_assert_held(&ct->lock); + + if (unlikely(ct->ctbs.h2g.info.broken)) { + ret = -EPIPE; + goto out; + } + + if (ct->state == XE_GUC_CT_STATE_DISABLED) { + ret = -ENODEV; + goto out; + } + + if (ct->state == XE_GUC_CT_STATE_STOPPED) { + ret = -ECANCELED; + goto out; + } + + xe_gt_assert(gt, xe_guc_ct_enabled(ct)); + + if (g2h_fence) { + g2h_len = GUC_CTB_HXG_MSG_MAX_LEN; + num_g2h = 1; + + if (g2h_fence_needs_alloc(g2h_fence)) { + g2h_fence->seqno = next_ct_seqno(ct, true); + ret = xa_err(xa_store(&ct->fence_lookup, + g2h_fence->seqno, g2h_fence, + GFP_ATOMIC)); + if (ret) + goto out; + } + + seqno = g2h_fence->seqno; + } else { + seqno = next_ct_seqno(ct, false); + } + + if (g2h_len) + spin_lock_irq(&ct->fast_lock); +retry: + ret = has_room(ct, len + GUC_CTB_HDR_LEN, g2h_len); + if (unlikely(ret)) + goto out_unlock; + + ret = h2g_write(ct, action, len, seqno, !!g2h_fence); + if (unlikely(ret)) { + if (ret == -EAGAIN) + goto retry; + goto out_unlock; + } + + __g2h_reserve_space(ct, g2h_len, num_g2h); + xe_guc_notify(ct_to_guc(ct)); +out_unlock: + if (g2h_len) + spin_unlock_irq(&ct->fast_lock); +out: + return ret; +} + +static void kick_reset(struct xe_guc_ct *ct) +{ + xe_gt_reset_async(ct_to_gt(ct)); +} + +static int dequeue_one_g2h(struct xe_guc_ct *ct); + +static int guc_ct_send_locked(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 g2h_len, u32 num_g2h, + struct g2h_fence *g2h_fence) +{ + struct xe_device *xe = ct_to_xe(ct); + struct xe_gt *gt = ct_to_gt(ct); + unsigned int sleep_period_ms = 1; + int ret; + + xe_gt_assert(gt, !g2h_len || !g2h_fence); + lockdep_assert_held(&ct->lock); + xe_device_assert_mem_access(ct_to_xe(ct)); + +try_again: + ret = __guc_ct_send_locked(ct, action, len, g2h_len, num_g2h, + g2h_fence); + + /* + * We wait to try to restore credits for about 1 second before bailing. + * In the case of H2G credits we have no choice but just to wait for the + * GuC to consume H2Gs in the channel so we use a wait / sleep loop. In + * the case of G2H we process any G2H in the channel, hopefully freeing + * credits as we consume the G2H messages. + */ + if (unlikely(ret == -EBUSY && + !h2g_has_room(ct, len + GUC_CTB_HDR_LEN))) { + struct guc_ctb *h2g = &ct->ctbs.h2g; + + if (sleep_period_ms == 1024) + goto broken; + + trace_xe_guc_ct_h2g_flow_control(xe, h2g->info.head, h2g->info.tail, + h2g->info.size, + h2g->info.space, + len + GUC_CTB_HDR_LEN); + msleep(sleep_period_ms); + sleep_period_ms <<= 1; + + goto try_again; + } else if (unlikely(ret == -EBUSY)) { + struct xe_device *xe = ct_to_xe(ct); + struct guc_ctb *g2h = &ct->ctbs.g2h; + + trace_xe_guc_ct_g2h_flow_control(xe, g2h->info.head, + desc_read(xe, g2h, tail), + g2h->info.size, + g2h->info.space, + g2h_fence ? + GUC_CTB_HXG_MSG_MAX_LEN : + g2h_len); + +#define g2h_avail(ct) \ + (desc_read(ct_to_xe(ct), (&ct->ctbs.g2h), tail) != ct->ctbs.g2h.info.head) + if (!wait_event_timeout(ct->wq, !ct->g2h_outstanding || + g2h_avail(ct), HZ)) + goto broken; +#undef g2h_avail + + ret = dequeue_one_g2h(ct); + if (ret < 0) { + if (ret != -ECANCELED) + xe_gt_err(ct_to_gt(ct), "CTB receive failed (%pe)", + ERR_PTR(ret)); + goto broken; + } + + goto try_again; + } + + return ret; + +broken: + xe_gt_err(gt, "No forward process on H2G, reset required\n"); + CT_DEAD(ct, &ct->ctbs.h2g, DEADLOCK); + + return -EDEADLK; +} + +static int guc_ct_send(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 g2h_len, u32 num_g2h, struct g2h_fence *g2h_fence) +{ + int ret; + + xe_gt_assert(ct_to_gt(ct), !g2h_len || !g2h_fence); + + mutex_lock(&ct->lock); + ret = guc_ct_send_locked(ct, action, len, g2h_len, num_g2h, g2h_fence); + mutex_unlock(&ct->lock); + + return ret; +} + +int xe_guc_ct_send(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 g2h_len, u32 num_g2h) +{ + int ret; + + ret = guc_ct_send(ct, action, len, g2h_len, num_g2h, NULL); + if (ret == -EDEADLK) + kick_reset(ct); + + return ret; +} + +int xe_guc_ct_send_locked(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 g2h_len, u32 num_g2h) +{ + int ret; + + ret = guc_ct_send_locked(ct, action, len, g2h_len, num_g2h, NULL); + if (ret == -EDEADLK) + kick_reset(ct); + + return ret; +} + +int xe_guc_ct_send_g2h_handler(struct xe_guc_ct *ct, const u32 *action, u32 len) +{ + int ret; + + lockdep_assert_held(&ct->lock); + + ret = guc_ct_send_locked(ct, action, len, 0, 0, NULL); + if (ret == -EDEADLK) + kick_reset(ct); + + return ret; +} + +/* + * Check if a GT reset is in progress or will occur and if GT reset brought the + * CT back up. Randomly picking 5 seconds for an upper limit to do a GT a reset. + */ +static bool retry_failure(struct xe_guc_ct *ct, int ret) +{ + if (!(ret == -EDEADLK || ret == -EPIPE || ret == -ENODEV)) + return false; + +#define ct_alive(ct) \ + (xe_guc_ct_enabled(ct) && !ct->ctbs.h2g.info.broken && \ + !ct->ctbs.g2h.info.broken) + if (!wait_event_interruptible_timeout(ct->wq, ct_alive(ct), HZ * 5)) + return false; +#undef ct_alive + + return true; +} + +static int guc_ct_send_recv(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 *response_buffer, bool no_fail) +{ + struct xe_gt *gt = ct_to_gt(ct); + struct g2h_fence g2h_fence; + int ret = 0; + + /* + * We use a fence to implement blocking sends / receiving response data. + * The seqno of the fence is sent in the H2G, returned in the G2H, and + * an xarray is used as storage media with the seqno being to key. + * Fields in the fence hold success, failure, retry status and the + * response data. Safe to allocate on the stack as the xarray is the + * only reference and it cannot be present after this function exits. + */ +retry: + g2h_fence_init(&g2h_fence, response_buffer); +retry_same_fence: + ret = guc_ct_send(ct, action, len, 0, 0, &g2h_fence); + if (unlikely(ret == -ENOMEM)) { + /* Retry allocation /w GFP_KERNEL */ + ret = xa_err(xa_store(&ct->fence_lookup, g2h_fence.seqno, + &g2h_fence, GFP_KERNEL)); + if (ret) + return ret; + + goto retry_same_fence; + } else if (unlikely(ret)) { + if (ret == -EDEADLK) + kick_reset(ct); + + if (no_fail && retry_failure(ct, ret)) + goto retry_same_fence; + + if (!g2h_fence_needs_alloc(&g2h_fence)) + xa_erase(&ct->fence_lookup, g2h_fence.seqno); + + return ret; + } + + ret = wait_event_timeout(ct->g2h_fence_wq, g2h_fence.done, HZ); + if (!ret) { + LNL_FLUSH_WORK(&ct->g2h_worker); + if (g2h_fence.done) { + xe_gt_warn(gt, "G2H fence %u, action %04x, done\n", + g2h_fence.seqno, action[0]); + ret = 1; + } + } + + /* + * Ensure we serialize with completion side to prevent UAF with fence going out of scope on + * the stack, since we have no clue if it will fire after the timeout before we can erase + * from the xa. Also we have some dependent loads and stores below for which we need the + * correct ordering, and we lack the needed barriers. + */ + mutex_lock(&ct->lock); + if (!ret) { + xe_gt_err(gt, "Timed out wait for G2H, fence %u, action %04x, done %s", + g2h_fence.seqno, action[0], str_yes_no(g2h_fence.done)); + xa_erase(&ct->fence_lookup, g2h_fence.seqno); + mutex_unlock(&ct->lock); + return -ETIME; + } + + if (g2h_fence.retry) { + xe_gt_dbg(gt, "H2G action %#x retrying: reason %#x\n", + action[0], g2h_fence.reason); + mutex_unlock(&ct->lock); + goto retry; + } + if (g2h_fence.fail) { + xe_gt_err(gt, "H2G request %#x failed: error %#x hint %#x\n", + action[0], g2h_fence.error, g2h_fence.hint); + ret = -EIO; + } + + if (ret > 0) + ret = response_buffer ? g2h_fence.response_len : g2h_fence.response_data; + + mutex_unlock(&ct->lock); + + return ret; +} + +/** + * xe_guc_ct_send_recv - Send and receive HXG to the GuC + * @ct: the &xe_guc_ct + * @action: the dword array with `HXG Request`_ message (can't be NULL) + * @len: length of the `HXG Request`_ message (in dwords, can't be 0) + * @response_buffer: placeholder for the `HXG Response`_ message (can be NULL) + * + * Send a `HXG Request`_ message to the GuC over CT communication channel and + * blocks until GuC replies with a `HXG Response`_ message. + * + * For non-blocking communication with GuC use xe_guc_ct_send(). + * + * Note: The size of &response_buffer must be at least GUC_CTB_MAX_DWORDS_. + * + * Return: response length (in dwords) if &response_buffer was not NULL, or + * DATA0 from `HXG Response`_ if &response_buffer was NULL, or + * a negative error code on failure. + */ +int xe_guc_ct_send_recv(struct xe_guc_ct *ct, const u32 *action, u32 len, + u32 *response_buffer) +{ + KUNIT_STATIC_STUB_REDIRECT(xe_guc_ct_send_recv, ct, action, len, response_buffer); + return guc_ct_send_recv(ct, action, len, response_buffer, false); +} + +int xe_guc_ct_send_recv_no_fail(struct xe_guc_ct *ct, const u32 *action, + u32 len, u32 *response_buffer) +{ + return guc_ct_send_recv(ct, action, len, response_buffer, true); +} + +static u32 *msg_to_hxg(u32 *msg) +{ + return msg + GUC_CTB_MSG_MIN_LEN; +} + +static u32 msg_len_to_hxg_len(u32 len) +{ + return len - GUC_CTB_MSG_MIN_LEN; +} + +static int parse_g2h_event(struct xe_guc_ct *ct, u32 *msg, u32 len) +{ + u32 *hxg = msg_to_hxg(msg); + u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]); + + lockdep_assert_held(&ct->lock); + + switch (action) { + case XE_GUC_ACTION_SCHED_CONTEXT_MODE_DONE: + case XE_GUC_ACTION_DEREGISTER_CONTEXT_DONE: + case XE_GUC_ACTION_SCHED_ENGINE_MODE_DONE: + case XE_GUC_ACTION_TLB_INVALIDATION_DONE: + g2h_release_space(ct, len); + } + + return 0; +} + +static int parse_g2h_response(struct xe_guc_ct *ct, u32 *msg, u32 len) +{ + struct xe_gt *gt = ct_to_gt(ct); + u32 *hxg = msg_to_hxg(msg); + u32 hxg_len = msg_len_to_hxg_len(len); + u32 fence = FIELD_GET(GUC_CTB_MSG_0_FENCE, msg[0]); + u32 type = FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]); + struct g2h_fence *g2h_fence; + + lockdep_assert_held(&ct->lock); + + /* + * Fences for FAST_REQUEST messages are not tracked in ct->fence_lookup. + * Those messages should never fail, so if we do get an error back it + * means we're likely doing an illegal operation and the GuC is + * rejecting it. We have no way to inform the code that submitted the + * H2G that the message was rejected, so we need to escalate the + * failure to trigger a reset. + */ + if (fence & CT_SEQNO_UNTRACKED) { + if (type == GUC_HXG_TYPE_RESPONSE_FAILURE) + xe_gt_err(gt, "FAST_REQ H2G fence 0x%x failed! e=0x%x, h=%u\n", + fence, + FIELD_GET(GUC_HXG_FAILURE_MSG_0_ERROR, hxg[0]), + FIELD_GET(GUC_HXG_FAILURE_MSG_0_HINT, hxg[0])); + else + xe_gt_err(gt, "unexpected response %u for FAST_REQ H2G fence 0x%x!\n", + type, fence); + CT_DEAD(ct, NULL, PARSE_G2H_RESPONSE); + + return -EPROTO; + } + + g2h_fence = xa_erase(&ct->fence_lookup, fence); + if (unlikely(!g2h_fence)) { + /* Don't tear down channel, as send could've timed out */ + /* CT_DEAD(ct, NULL, PARSE_G2H_UNKNOWN); */ + xe_gt_warn(gt, "G2H fence (%u) not found!\n", fence); + g2h_release_space(ct, GUC_CTB_HXG_MSG_MAX_LEN); + return 0; + } + + xe_gt_assert(gt, fence == g2h_fence->seqno); + + if (type == GUC_HXG_TYPE_RESPONSE_FAILURE) { + g2h_fence->fail = true; + g2h_fence->error = FIELD_GET(GUC_HXG_FAILURE_MSG_0_ERROR, hxg[0]); + g2h_fence->hint = FIELD_GET(GUC_HXG_FAILURE_MSG_0_HINT, hxg[0]); + } else if (type == GUC_HXG_TYPE_NO_RESPONSE_RETRY) { + g2h_fence->retry = true; + g2h_fence->reason = FIELD_GET(GUC_HXG_RETRY_MSG_0_REASON, hxg[0]); + } else if (g2h_fence->response_buffer) { + g2h_fence->response_len = hxg_len; + memcpy(g2h_fence->response_buffer, hxg, hxg_len * sizeof(u32)); + } else { + g2h_fence->response_data = FIELD_GET(GUC_HXG_RESPONSE_MSG_0_DATA0, hxg[0]); + } + + g2h_release_space(ct, GUC_CTB_HXG_MSG_MAX_LEN); + + g2h_fence->done = true; + smp_mb(); + + wake_up_all(&ct->g2h_fence_wq); + + return 0; +} + +static int parse_g2h_msg(struct xe_guc_ct *ct, u32 *msg, u32 len) +{ + struct xe_gt *gt = ct_to_gt(ct); + u32 *hxg = msg_to_hxg(msg); + u32 origin, type; + int ret; + + lockdep_assert_held(&ct->lock); + + origin = FIELD_GET(GUC_HXG_MSG_0_ORIGIN, hxg[0]); + if (unlikely(origin != GUC_HXG_ORIGIN_GUC)) { + xe_gt_err(gt, "G2H channel broken on read, origin=%u, reset required\n", + origin); + CT_DEAD(ct, &ct->ctbs.g2h, PARSE_G2H_ORIGIN); + + return -EPROTO; + } + + type = FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]); + switch (type) { + case GUC_HXG_TYPE_EVENT: + ret = parse_g2h_event(ct, msg, len); + break; + case GUC_HXG_TYPE_RESPONSE_SUCCESS: + case GUC_HXG_TYPE_RESPONSE_FAILURE: + case GUC_HXG_TYPE_NO_RESPONSE_RETRY: + ret = parse_g2h_response(ct, msg, len); + break; + default: + xe_gt_err(gt, "G2H channel broken on read, type=%u, reset required\n", + type); + CT_DEAD(ct, &ct->ctbs.g2h, PARSE_G2H_TYPE); + + ret = -EOPNOTSUPP; + } + + return ret; +} + +static int process_g2h_msg(struct xe_guc_ct *ct, u32 *msg, u32 len) +{ + struct xe_guc *guc = ct_to_guc(ct); + struct xe_gt *gt = ct_to_gt(ct); + u32 hxg_len = msg_len_to_hxg_len(len); + u32 *hxg = msg_to_hxg(msg); + u32 action, adj_len; + u32 *payload; + int ret = 0; + + if (FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_EVENT) + return 0; + + action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]); + payload = hxg + GUC_HXG_EVENT_MSG_MIN_LEN; + adj_len = hxg_len - GUC_HXG_EVENT_MSG_MIN_LEN; + + switch (action) { + case XE_GUC_ACTION_SCHED_CONTEXT_MODE_DONE: + ret = xe_guc_sched_done_handler(guc, payload, adj_len); + break; + case XE_GUC_ACTION_DEREGISTER_CONTEXT_DONE: + ret = xe_guc_deregister_done_handler(guc, payload, adj_len); + break; + case XE_GUC_ACTION_CONTEXT_RESET_NOTIFICATION: + ret = xe_guc_exec_queue_reset_handler(guc, payload, adj_len); + break; + case XE_GUC_ACTION_ENGINE_FAILURE_NOTIFICATION: + ret = xe_guc_exec_queue_reset_failure_handler(guc, payload, + adj_len); + break; + case XE_GUC_ACTION_SCHED_ENGINE_MODE_DONE: + /* Selftest only at the moment */ + break; + case XE_GUC_ACTION_STATE_CAPTURE_NOTIFICATION: + ret = xe_guc_error_capture_handler(guc, payload, adj_len); + break; + case XE_GUC_ACTION_NOTIFY_FLUSH_LOG_BUFFER_TO_FILE: + /* FIXME: Handle this */ + break; + case XE_GUC_ACTION_NOTIFY_MEMORY_CAT_ERROR: + ret = xe_guc_exec_queue_memory_cat_error_handler(guc, payload, + adj_len); + break; + case XE_GUC_ACTION_REPORT_PAGE_FAULT_REQ_DESC: + ret = xe_guc_pagefault_handler(guc, payload, adj_len); + break; + case XE_GUC_ACTION_TLB_INVALIDATION_DONE: + ret = xe_guc_tlb_invalidation_done_handler(guc, payload, + adj_len); + break; + case XE_GUC_ACTION_ACCESS_COUNTER_NOTIFY: + ret = xe_guc_access_counter_notify_handler(guc, payload, + adj_len); + break; + case XE_GUC_ACTION_GUC2PF_RELAY_FROM_VF: + ret = xe_guc_relay_process_guc2pf(&guc->relay, hxg, hxg_len); + break; + case XE_GUC_ACTION_GUC2VF_RELAY_FROM_PF: + ret = xe_guc_relay_process_guc2vf(&guc->relay, hxg, hxg_len); + break; + case GUC_ACTION_GUC2PF_VF_STATE_NOTIFY: + ret = xe_gt_sriov_pf_control_process_guc2pf(gt, hxg, hxg_len); + break; + case GUC_ACTION_GUC2PF_ADVERSE_EVENT: + ret = xe_gt_sriov_pf_monitor_process_guc2pf(gt, hxg, hxg_len); + break; + default: + xe_gt_err(gt, "unexpected G2H action 0x%04x\n", action); + } + + if (ret) { + xe_gt_err(gt, "G2H action 0x%04x failed (%pe)\n", + action, ERR_PTR(ret)); + CT_DEAD(ct, NULL, PROCESS_FAILED); + } + + return 0; +} + +static int g2h_read(struct xe_guc_ct *ct, u32 *msg, bool fast_path) +{ + struct xe_device *xe = ct_to_xe(ct); + struct xe_gt *gt = ct_to_gt(ct); + struct guc_ctb *g2h = &ct->ctbs.g2h; + u32 tail, head, len, desc_status; + s32 avail; + u32 action; + u32 *hxg; + + xe_gt_assert(gt, ct->state != XE_GUC_CT_STATE_NOT_INITIALIZED); + lockdep_assert_held(&ct->fast_lock); + + if (ct->state == XE_GUC_CT_STATE_DISABLED) + return -ENODEV; + + if (ct->state == XE_GUC_CT_STATE_STOPPED) + return -ECANCELED; + + if (g2h->info.broken) + return -EPIPE; + + xe_gt_assert(gt, xe_guc_ct_enabled(ct)); + + desc_status = desc_read(xe, g2h, status); + if (desc_status) { + if (desc_status & GUC_CTB_STATUS_DISABLED) { + /* + * Potentially valid if a CLIENT_RESET request resulted in + * contexts/engines being reset. But should never happen as + * no contexts should be active when CLIENT_RESET is sent. + */ + xe_gt_err(gt, "CT read: unexpected G2H after GuC has stopped!\n"); + desc_status &= ~GUC_CTB_STATUS_DISABLED; + } + + if (desc_status) { + xe_gt_err(gt, "CT read: non-zero status: %u\n", desc_status); + goto corrupted; + } + } + + if (IS_ENABLED(CONFIG_DRM_XE_DEBUG)) { + u32 desc_tail = desc_read(xe, g2h, tail); + /* + u32 desc_head = desc_read(xe, g2h, head); + + * info.head and desc_head are updated back-to-back at the end of + * this function and nowhere else. Hence, they cannot be different + * unless two g2h_read calls are running concurrently. Which is not + * possible because it is guarded by ct->fast_lock. And yet, some + * discrete platforms are reguarly hitting this error :(. + * + * desc_head rolling backwards shouldn't cause any noticeable + * problems - just a delay in GuC being allowed to proceed past that + * point in the queue. So for now, just disable the error until it + * can be root caused. + * + if (g2h->info.head != desc_head) { + desc_write(xe, g2h, status, desc_status | GUC_CTB_STATUS_MISMATCH); + xe_gt_err(gt, "CT read: head was modified %u != %u\n", + desc_head, g2h->info.head); + goto corrupted; + } + */ + + if (g2h->info.head > g2h->info.size) { + desc_write(xe, g2h, status, desc_status | GUC_CTB_STATUS_OVERFLOW); + xe_gt_err(gt, "CT read: head out of range: %u vs %u\n", + g2h->info.head, g2h->info.size); + goto corrupted; + } + + if (desc_tail >= g2h->info.size) { + desc_write(xe, g2h, status, desc_status | GUC_CTB_STATUS_OVERFLOW); + xe_gt_err(gt, "CT read: invalid tail offset %u >= %u)\n", + desc_tail, g2h->info.size); + goto corrupted; + } + } + + /* Calculate DW available to read */ + tail = desc_read(xe, g2h, tail); + avail = tail - g2h->info.head; + if (unlikely(avail == 0)) + return 0; + + if (avail < 0) + avail += g2h->info.size; + + /* Read header */ + xe_map_memcpy_from(xe, msg, &g2h->cmds, sizeof(u32) * g2h->info.head, + sizeof(u32)); + len = FIELD_GET(GUC_CTB_MSG_0_NUM_DWORDS, msg[0]) + GUC_CTB_MSG_MIN_LEN; + if (len > avail) { + xe_gt_err(gt, "G2H channel broken on read, avail=%d, len=%d, reset required\n", + avail, len); + goto corrupted; + } + + head = (g2h->info.head + 1) % g2h->info.size; + avail = len - 1; + + /* Read G2H message */ + if (avail + head > g2h->info.size) { + u32 avail_til_wrap = g2h->info.size - head; + + xe_map_memcpy_from(xe, msg + 1, + &g2h->cmds, sizeof(u32) * head, + avail_til_wrap * sizeof(u32)); + xe_map_memcpy_from(xe, msg + 1 + avail_til_wrap, + &g2h->cmds, 0, + (avail - avail_til_wrap) * sizeof(u32)); + } else { + xe_map_memcpy_from(xe, msg + 1, + &g2h->cmds, sizeof(u32) * head, + avail * sizeof(u32)); + } + + hxg = msg_to_hxg(msg); + action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]); + + if (fast_path) { + if (FIELD_GET(GUC_HXG_MSG_0_TYPE, hxg[0]) != GUC_HXG_TYPE_EVENT) + return 0; + + switch (action) { + case XE_GUC_ACTION_REPORT_PAGE_FAULT_REQ_DESC: + case XE_GUC_ACTION_TLB_INVALIDATION_DONE: + break; /* Process these in fast-path */ + default: + return 0; + } + } + + /* Update local / descriptor header */ + g2h->info.head = (head + avail) % g2h->info.size; + desc_write(xe, g2h, head, g2h->info.head); + + trace_xe_guc_ctb_g2h(xe, ct_to_gt(ct)->info.id, + action, len, g2h->info.head, tail); + + return len; + +corrupted: + CT_DEAD(ct, &ct->ctbs.g2h, G2H_READ); + return -EPROTO; +} + +static void g2h_fast_path(struct xe_guc_ct *ct, u32 *msg, u32 len) +{ + struct xe_gt *gt = ct_to_gt(ct); + struct xe_guc *guc = ct_to_guc(ct); + u32 hxg_len = msg_len_to_hxg_len(len); + u32 *hxg = msg_to_hxg(msg); + u32 action = FIELD_GET(GUC_HXG_EVENT_MSG_0_ACTION, hxg[0]); + u32 *payload = hxg + GUC_HXG_MSG_MIN_LEN; + u32 adj_len = hxg_len - GUC_HXG_MSG_MIN_LEN; + int ret = 0; + + switch (action) { + case XE_GUC_ACTION_REPORT_PAGE_FAULT_REQ_DESC: + ret = xe_guc_pagefault_handler(guc, payload, adj_len); + break; + case XE_GUC_ACTION_TLB_INVALIDATION_DONE: + __g2h_release_space(ct, len); + ret = xe_guc_tlb_invalidation_done_handler(guc, payload, + adj_len); + break; + default: + xe_gt_warn(gt, "NOT_POSSIBLE"); + } + + if (ret) { + xe_gt_err(gt, "G2H action 0x%04x failed (%pe)\n", + action, ERR_PTR(ret)); + CT_DEAD(ct, NULL, FAST_G2H); + } +} + +/** + * xe_guc_ct_fast_path - process critical G2H in the IRQ handler + * @ct: GuC CT object + * + * Anything related to page faults is critical for performance, process these + * critical G2H in the IRQ. This is safe as these handlers either just wake up + * waiters or queue another worker. + */ +void xe_guc_ct_fast_path(struct xe_guc_ct *ct) +{ + struct xe_device *xe = ct_to_xe(ct); + bool ongoing; + int len; + + ongoing = xe_pm_runtime_get_if_active(ct_to_xe(ct)); + if (!ongoing && xe_pm_read_callback_task(ct_to_xe(ct)) == NULL) + return; + + spin_lock(&ct->fast_lock); + do { + len = g2h_read(ct, ct->fast_msg, true); + if (len > 0) + g2h_fast_path(ct, ct->fast_msg, len); + } while (len > 0); + spin_unlock(&ct->fast_lock); + + if (ongoing) + xe_pm_runtime_put(xe); +} + +/* Returns less than zero on error, 0 on done, 1 on more available */ +static int dequeue_one_g2h(struct xe_guc_ct *ct) +{ + int len; + int ret; + + lockdep_assert_held(&ct->lock); + + spin_lock_irq(&ct->fast_lock); + len = g2h_read(ct, ct->msg, false); + spin_unlock_irq(&ct->fast_lock); + if (len <= 0) + return len; + + ret = parse_g2h_msg(ct, ct->msg, len); + if (unlikely(ret < 0)) + return ret; + + ret = process_g2h_msg(ct, ct->msg, len); + if (unlikely(ret < 0)) + return ret; + + return 1; +} + +static void receive_g2h(struct xe_guc_ct *ct) +{ + bool ongoing; + int ret; + + /* + * Normal users must always hold mem_access.ref around CT calls. However + * during the runtime pm callbacks we rely on CT to talk to the GuC, but + * at this stage we can't rely on mem_access.ref and even the + * callback_task will be different than current. For such cases we just + * need to ensure we always process the responses from any blocking + * ct_send requests or where we otherwise expect some response when + * initiated from those callbacks (which will need to wait for the below + * dequeue_one_g2h()). The dequeue_one_g2h() will gracefully fail if + * the device has suspended to the point that the CT communication has + * been disabled. + * + * If we are inside the runtime pm callback, we can be the only task + * still issuing CT requests (since that requires having the + * mem_access.ref). It seems like it might in theory be possible to + * receive unsolicited events from the GuC just as we are + * suspending-resuming, but those will currently anyway be lost when + * eventually exiting from suspend, hence no need to wake up the device + * here. If we ever need something stronger than get_if_ongoing() then + * we need to be careful with blocking the pm callbacks from getting CT + * responses, if the worker here is blocked on those callbacks + * completing, creating a deadlock. + */ + ongoing = xe_pm_runtime_get_if_active(ct_to_xe(ct)); + if (!ongoing && xe_pm_read_callback_task(ct_to_xe(ct)) == NULL) + return; + + do { + mutex_lock(&ct->lock); + ret = dequeue_one_g2h(ct); + mutex_unlock(&ct->lock); + + if (unlikely(ret == -EPROTO || ret == -EOPNOTSUPP)) { + xe_gt_err(ct_to_gt(ct), "CT dequeue failed: %d", ret); + CT_DEAD(ct, NULL, G2H_RECV); + kick_reset(ct); + } + } while (ret == 1); + + if (ongoing) + xe_pm_runtime_put(ct_to_xe(ct)); +} + +static void g2h_worker_func(struct work_struct *w) +{ + struct xe_guc_ct *ct = container_of(w, struct xe_guc_ct, g2h_worker); + + receive_g2h(ct); +} + +static struct xe_guc_ct_snapshot *guc_ct_snapshot_alloc(struct xe_guc_ct *ct, bool atomic, + bool want_ctb) +{ + struct xe_guc_ct_snapshot *snapshot; + + snapshot = kzalloc(sizeof(*snapshot), atomic ? GFP_ATOMIC : GFP_KERNEL); + if (!snapshot) + return NULL; + + if (ct->bo && want_ctb) { + snapshot->ctb_size = ct->bo->size; + snapshot->ctb = kmalloc(snapshot->ctb_size, atomic ? GFP_ATOMIC : GFP_KERNEL); + } + + return snapshot; +} + +static void guc_ctb_snapshot_capture(struct xe_device *xe, struct guc_ctb *ctb, + struct guc_ctb_snapshot *snapshot) +{ + xe_map_memcpy_from(xe, &snapshot->desc, &ctb->desc, 0, + sizeof(struct guc_ct_buffer_desc)); + memcpy(&snapshot->info, &ctb->info, sizeof(struct guc_ctb_info)); +} + +static void guc_ctb_snapshot_print(struct guc_ctb_snapshot *snapshot, + struct drm_printer *p) +{ + drm_printf(p, "\tsize: %d\n", snapshot->info.size); + drm_printf(p, "\tresv_space: %d\n", snapshot->info.resv_space); + drm_printf(p, "\thead: %d\n", snapshot->info.head); + drm_printf(p, "\ttail: %d\n", snapshot->info.tail); + drm_printf(p, "\tspace: %d\n", snapshot->info.space); + drm_printf(p, "\tbroken: %d\n", snapshot->info.broken); + drm_printf(p, "\thead (memory): %d\n", snapshot->desc.head); + drm_printf(p, "\ttail (memory): %d\n", snapshot->desc.tail); + drm_printf(p, "\tstatus (memory): 0x%x\n", snapshot->desc.status); +} + +static struct xe_guc_ct_snapshot *guc_ct_snapshot_capture(struct xe_guc_ct *ct, bool atomic, + bool want_ctb) +{ + struct xe_device *xe = ct_to_xe(ct); + struct xe_guc_ct_snapshot *snapshot; + + snapshot = guc_ct_snapshot_alloc(ct, atomic, want_ctb); + if (!snapshot) { + xe_gt_err(ct_to_gt(ct), "Skipping CTB snapshot entirely.\n"); + return NULL; + } + + if (xe_guc_ct_enabled(ct) || ct->state == XE_GUC_CT_STATE_STOPPED) { + snapshot->ct_enabled = true; + snapshot->g2h_outstanding = READ_ONCE(ct->g2h_outstanding); + guc_ctb_snapshot_capture(xe, &ct->ctbs.h2g, &snapshot->h2g); + guc_ctb_snapshot_capture(xe, &ct->ctbs.g2h, &snapshot->g2h); + } + + if (ct->bo && snapshot->ctb) + xe_map_memcpy_from(xe, snapshot->ctb, &ct->bo->vmap, 0, snapshot->ctb_size); + + return snapshot; +} + +/** + * xe_guc_ct_snapshot_capture - Take a quick snapshot of the CT state. + * @ct: GuC CT object. + * + * This can be printed out in a later stage like during dev_coredump + * analysis. This is safe to be called during atomic context. + * + * Returns: a GuC CT snapshot object that must be freed by the caller + * by using `xe_guc_ct_snapshot_free`. + */ +struct xe_guc_ct_snapshot *xe_guc_ct_snapshot_capture(struct xe_guc_ct *ct) +{ + return guc_ct_snapshot_capture(ct, true, true); +} + +/** + * xe_guc_ct_snapshot_print - Print out a given GuC CT snapshot. + * @snapshot: GuC CT snapshot object. + * @p: drm_printer where it will be printed out. + * + * This function prints out a given GuC CT snapshot object. + */ +void xe_guc_ct_snapshot_print(struct xe_guc_ct_snapshot *snapshot, + struct drm_printer *p) +{ + if (!snapshot) + return; + + if (snapshot->ct_enabled) { + drm_puts(p, "H2G CTB (all sizes in DW):\n"); + guc_ctb_snapshot_print(&snapshot->h2g, p); + + drm_puts(p, "G2H CTB (all sizes in DW):\n"); + guc_ctb_snapshot_print(&snapshot->g2h, p); + drm_printf(p, "\tg2h outstanding: %d\n", + snapshot->g2h_outstanding); + + if (snapshot->ctb) + xe_print_blob_ascii85(p, "CTB data", snapshot->ctb, 0, snapshot->ctb_size); + } else { + drm_puts(p, "CT disabled\n"); + } +} + +/** + * xe_guc_ct_snapshot_free - Free all allocated objects for a given snapshot. + * @snapshot: GuC CT snapshot object. + * + * This function free all the memory that needed to be allocated at capture + * time. + */ +void xe_guc_ct_snapshot_free(struct xe_guc_ct_snapshot *snapshot) +{ + if (!snapshot) + return; + + kfree(snapshot->ctb); + kfree(snapshot); +} + +/** + * xe_guc_ct_print - GuC CT Print. + * @ct: GuC CT. + * @p: drm_printer where it will be printed out. + * @want_ctb: Should the full CTB content be dumped (vs just the headers) + * + * This function will quickly capture a snapshot of the CT state + * and immediately print it out. + */ +void xe_guc_ct_print(struct xe_guc_ct *ct, struct drm_printer *p, bool want_ctb) +{ + struct xe_guc_ct_snapshot *snapshot; + + snapshot = guc_ct_snapshot_capture(ct, false, want_ctb); + xe_guc_ct_snapshot_print(snapshot, p); + xe_guc_ct_snapshot_free(snapshot); +} + +#if IS_ENABLED(CONFIG_DRM_XE_DEBUG) +static void ct_dead_capture(struct xe_guc_ct *ct, struct guc_ctb *ctb, u32 reason_code) +{ + struct xe_guc_log_snapshot *snapshot_log; + struct xe_guc_ct_snapshot *snapshot_ct; + struct xe_guc *guc = ct_to_guc(ct); + unsigned long flags; + bool have_capture; + + if (ctb) + ctb->info.broken = true; + + /* Ignore further errors after the first dump until a reset */ + if (ct->dead.reported) + return; + + spin_lock_irqsave(&ct->dead.lock, flags); + + /* And only capture one dump at a time */ + have_capture = ct->dead.reason & (1 << CT_DEAD_STATE_CAPTURE); + ct->dead.reason |= (1 << reason_code) | + (1 << CT_DEAD_STATE_CAPTURE); + + spin_unlock_irqrestore(&ct->dead.lock, flags); + + if (have_capture) + return; + + snapshot_log = xe_guc_log_snapshot_capture(&guc->log, true); + snapshot_ct = xe_guc_ct_snapshot_capture((ct)); + + spin_lock_irqsave(&ct->dead.lock, flags); + + if (ct->dead.snapshot_log || ct->dead.snapshot_ct) { + xe_gt_err(ct_to_gt(ct), "Got unexpected dead CT capture!\n"); + xe_guc_log_snapshot_free(snapshot_log); + xe_guc_ct_snapshot_free(snapshot_ct); + } else { + ct->dead.snapshot_log = snapshot_log; + ct->dead.snapshot_ct = snapshot_ct; + } + + spin_unlock_irqrestore(&ct->dead.lock, flags); + + queue_work(system_unbound_wq, &(ct)->dead.worker); +} + +static void ct_dead_print(struct xe_dead_ct *dead) +{ + struct xe_guc_ct *ct = container_of(dead, struct xe_guc_ct, dead); + struct xe_device *xe = ct_to_xe(ct); + struct xe_gt *gt = ct_to_gt(ct); + static int g_count; + struct drm_printer ip = xe_gt_info_printer(gt); + struct drm_printer lp = drm_line_printer(&ip, "Capture", ++g_count); + + if (!dead->reason) { + xe_gt_err(gt, "CTB is dead for no reason!?\n"); + return; + } + + drm_printf(&lp, "CTB is dead - reason=0x%X\n", dead->reason); + + /* Can't generate a genuine core dump at this point, so just do the good bits */ + drm_puts(&lp, "**** Xe Device Coredump ****\n"); + xe_device_snapshot_print(xe, &lp); + + drm_printf(&lp, "**** GT #%d ****\n", gt->info.id); + drm_printf(&lp, "\tTile: %d\n", gt->tile->id); + + drm_puts(&lp, "**** GuC Log ****\n"); + xe_guc_log_snapshot_print(dead->snapshot_log, &lp); + + drm_puts(&lp, "**** GuC CT ****\n"); + xe_guc_ct_snapshot_print(dead->snapshot_ct, &lp); + + drm_puts(&lp, "Done.\n"); +} + +static void ct_dead_worker_func(struct work_struct *w) +{ + struct xe_guc_ct *ct = container_of(w, struct xe_guc_ct, dead.worker); + + if (!ct->dead.reported) { + ct->dead.reported = true; + ct_dead_print(&ct->dead); + } + + spin_lock_irq(&ct->dead.lock); + + xe_guc_log_snapshot_free(ct->dead.snapshot_log); + ct->dead.snapshot_log = NULL; + xe_guc_ct_snapshot_free(ct->dead.snapshot_ct); + ct->dead.snapshot_ct = NULL; + + if (ct->dead.reason & (1 << CT_DEAD_STATE_REARM)) { + /* A reset has occurred so re-arm the error reporting */ + ct->dead.reason = 0; + ct->dead.reported = false; + } + + spin_unlock_irq(&ct->dead.lock); +} +#endif |