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|
/*
* Copyright © 2014 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
*/
#include <linux/firmware.h>
#include <linux/circ_buf.h>
#include "i915_drv.h"
#include "intel_guc.h"
/**
* DOC: GuC-based command submission
*
* i915_guc_client:
* We use the term client to avoid confusion with contexts. A i915_guc_client is
* equivalent to GuC object guc_context_desc. This context descriptor is
* allocated from a pool of 1024 entries. Kernel driver will allocate doorbell
* and workqueue for it. Also the process descriptor (guc_process_desc), which
* is mapped to client space. So the client can write Work Item then ring the
* doorbell.
*
* To simplify the implementation, we allocate one gem object that contains all
* pages for doorbell, process descriptor and workqueue.
*
* The Scratch registers:
* There are 16 MMIO-based registers start from 0xC180. The kernel driver writes
* a value to the action register (SOFT_SCRATCH_0) along with any data. It then
* triggers an interrupt on the GuC via another register write (0xC4C8).
* Firmware writes a success/fail code back to the action register after
* processes the request. The kernel driver polls waiting for this update and
* then proceeds.
* See host2guc_action()
*
* Doorbells:
* Doorbells are interrupts to uKernel. A doorbell is a single cache line (QW)
* mapped into process space.
*
* Work Items:
* There are several types of work items that the host may place into a
* workqueue, each with its own requirements and limitations. Currently only
* WQ_TYPE_INORDER is needed to support legacy submission via GuC, which
* represents in-order queue. The kernel driver packs ring tail pointer and an
* ELSP context descriptor dword into Work Item.
* See guc_add_workqueue_item()
*
*/
/*
* Read GuC command/status register (SOFT_SCRATCH_0)
* Return true if it contains a response rather than a command
*/
static inline bool host2guc_action_response(struct drm_i915_private *dev_priv,
u32 *status)
{
u32 val = I915_READ(SOFT_SCRATCH(0));
*status = val;
return GUC2HOST_IS_RESPONSE(val);
}
static int host2guc_action(struct intel_guc *guc, u32 *data, u32 len)
{
struct drm_i915_private *dev_priv = guc_to_i915(guc);
u32 status;
int i;
int ret;
if (WARN_ON(len < 1 || len > 15))
return -EINVAL;
intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
dev_priv->guc.action_count += 1;
dev_priv->guc.action_cmd = data[0];
for (i = 0; i < len; i++)
I915_WRITE(SOFT_SCRATCH(i), data[i]);
POSTING_READ(SOFT_SCRATCH(i - 1));
I915_WRITE(HOST2GUC_INTERRUPT, HOST2GUC_TRIGGER);
/*
* Fast commands should complete in less than 10us, so sample quickly
* up to that length of time, then switch to a slower sleep-wait loop.
* No HOST2GUC command should ever take longer than 10ms.
*/
ret = wait_for_us(host2guc_action_response(dev_priv, &status), 10);
if (ret)
ret = wait_for(host2guc_action_response(dev_priv, &status), 10);
if (status != GUC2HOST_STATUS_SUCCESS) {
/*
* Either the GuC explicitly returned an error (which
* we convert to -EIO here) or no response at all was
* received within the timeout limit (-ETIMEDOUT)
*/
if (ret != -ETIMEDOUT)
ret = -EIO;
DRM_ERROR("GUC: host2guc action 0x%X failed. ret=%d "
"status=0x%08X response=0x%08X\n",
data[0], ret, status,
I915_READ(SOFT_SCRATCH(15)));
dev_priv->guc.action_fail += 1;
dev_priv->guc.action_err = ret;
}
dev_priv->guc.action_status = status;
intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
return ret;
}
/*
* Tell the GuC to allocate or deallocate a specific doorbell
*/
static int host2guc_allocate_doorbell(struct intel_guc *guc,
struct i915_guc_client *client)
{
u32 data[2];
data[0] = HOST2GUC_ACTION_ALLOCATE_DOORBELL;
data[1] = client->ctx_index;
return host2guc_action(guc, data, 2);
}
static int host2guc_release_doorbell(struct intel_guc *guc,
struct i915_guc_client *client)
{
u32 data[2];
data[0] = HOST2GUC_ACTION_DEALLOCATE_DOORBELL;
data[1] = client->ctx_index;
return host2guc_action(guc, data, 2);
}
static int host2guc_sample_forcewake(struct intel_guc *guc,
struct i915_guc_client *client)
{
struct drm_i915_private *dev_priv = guc_to_i915(guc);
u32 data[2];
data[0] = HOST2GUC_ACTION_SAMPLE_FORCEWAKE;
/* WaRsDisableCoarsePowerGating:skl,bxt */
if (!intel_enable_rc6() || NEEDS_WaRsDisableCoarsePowerGating(dev_priv))
data[1] = 0;
else
/* bit 0 and 1 are for Render and Media domain separately */
data[1] = GUC_FORCEWAKE_RENDER | GUC_FORCEWAKE_MEDIA;
return host2guc_action(guc, data, ARRAY_SIZE(data));
}
/*
* Initialise, update, or clear doorbell data shared with the GuC
*
* These functions modify shared data and so need access to the mapped
* client object which contains the page being used for the doorbell
*/
static int guc_update_doorbell_id(struct intel_guc *guc,
struct i915_guc_client *client,
u16 new_id)
{
struct sg_table *sg = guc->ctx_pool_obj->pages;
void *doorbell_bitmap = guc->doorbell_bitmap;
struct guc_doorbell_info *doorbell;
struct guc_context_desc desc;
size_t len;
doorbell = client->client_base + client->doorbell_offset;
if (client->doorbell_id != GUC_INVALID_DOORBELL_ID &&
test_bit(client->doorbell_id, doorbell_bitmap)) {
/* Deactivate the old doorbell */
doorbell->db_status = GUC_DOORBELL_DISABLED;
(void)host2guc_release_doorbell(guc, client);
__clear_bit(client->doorbell_id, doorbell_bitmap);
}
/* Update the GuC's idea of the doorbell ID */
len = sg_pcopy_to_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
sizeof(desc) * client->ctx_index);
if (len != sizeof(desc))
return -EFAULT;
desc.db_id = new_id;
len = sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
sizeof(desc) * client->ctx_index);
if (len != sizeof(desc))
return -EFAULT;
client->doorbell_id = new_id;
if (new_id == GUC_INVALID_DOORBELL_ID)
return 0;
/* Activate the new doorbell */
__set_bit(new_id, doorbell_bitmap);
doorbell->cookie = 0;
doorbell->db_status = GUC_DOORBELL_ENABLED;
return host2guc_allocate_doorbell(guc, client);
}
static int guc_init_doorbell(struct intel_guc *guc,
struct i915_guc_client *client,
uint16_t db_id)
{
return guc_update_doorbell_id(guc, client, db_id);
}
static void guc_disable_doorbell(struct intel_guc *guc,
struct i915_guc_client *client)
{
(void)guc_update_doorbell_id(guc, client, GUC_INVALID_DOORBELL_ID);
/* XXX: wait for any interrupts */
/* XXX: wait for workqueue to drain */
}
static uint16_t
select_doorbell_register(struct intel_guc *guc, uint32_t priority)
{
/*
* The bitmap tracks which doorbell registers are currently in use.
* It is split into two halves; the first half is used for normal
* priority contexts, the second half for high-priority ones.
* Note that logically higher priorities are numerically less than
* normal ones, so the test below means "is it high-priority?"
*/
const bool hi_pri = (priority <= GUC_CTX_PRIORITY_HIGH);
const uint16_t half = GUC_MAX_DOORBELLS / 2;
const uint16_t start = hi_pri ? half : 0;
const uint16_t end = start + half;
uint16_t id;
id = find_next_zero_bit(guc->doorbell_bitmap, end, start);
if (id == end)
id = GUC_INVALID_DOORBELL_ID;
DRM_DEBUG_DRIVER("assigned %s priority doorbell id 0x%x\n",
hi_pri ? "high" : "normal", id);
return id;
}
/*
* Select, assign and relase doorbell cachelines
*
* These functions track which doorbell cachelines are in use.
* The data they manipulate is protected by the host2guc lock.
*/
static uint32_t select_doorbell_cacheline(struct intel_guc *guc)
{
const uint32_t cacheline_size = cache_line_size();
uint32_t offset;
/* Doorbell uses a single cache line within a page */
offset = offset_in_page(guc->db_cacheline);
/* Moving to next cache line to reduce contention */
guc->db_cacheline += cacheline_size;
DRM_DEBUG_DRIVER("selected doorbell cacheline 0x%x, next 0x%x, linesize %u\n",
offset, guc->db_cacheline, cacheline_size);
return offset;
}
/*
* Initialise the process descriptor shared with the GuC firmware.
*/
static void guc_init_proc_desc(struct intel_guc *guc,
struct i915_guc_client *client)
{
struct guc_process_desc *desc;
desc = client->client_base + client->proc_desc_offset;
memset(desc, 0, sizeof(*desc));
/*
* XXX: pDoorbell and WQVBaseAddress are pointers in process address
* space for ring3 clients (set them as in mmap_ioctl) or kernel
* space for kernel clients (map on demand instead? May make debug
* easier to have it mapped).
*/
desc->wq_base_addr = 0;
desc->db_base_addr = 0;
desc->context_id = client->ctx_index;
desc->wq_size_bytes = client->wq_size;
desc->wq_status = WQ_STATUS_ACTIVE;
desc->priority = client->priority;
}
/*
* Initialise/clear the context descriptor shared with the GuC firmware.
*
* This descriptor tells the GuC where (in GGTT space) to find the important
* data structures relating to this client (doorbell, process descriptor,
* write queue, etc).
*/
static void guc_init_ctx_desc(struct intel_guc *guc,
struct i915_guc_client *client)
{
struct drm_i915_gem_object *client_obj = client->client_obj;
struct drm_i915_private *dev_priv = guc_to_i915(guc);
struct intel_engine_cs *engine;
struct i915_gem_context *ctx = client->owner;
struct guc_context_desc desc;
struct sg_table *sg;
u32 gfx_addr;
memset(&desc, 0, sizeof(desc));
desc.attribute = GUC_CTX_DESC_ATTR_ACTIVE | GUC_CTX_DESC_ATTR_KERNEL;
desc.context_id = client->ctx_index;
desc.priority = client->priority;
desc.db_id = client->doorbell_id;
for_each_engine(engine, dev_priv) {
struct intel_context *ce = &ctx->engine[engine->id];
struct guc_execlist_context *lrc = &desc.lrc[engine->guc_id];
struct drm_i915_gem_object *obj;
/* TODO: We have a design issue to be solved here. Only when we
* receive the first batch, we know which engine is used by the
* user. But here GuC expects the lrc and ring to be pinned. It
* is not an issue for default context, which is the only one
* for now who owns a GuC client. But for future owner of GuC
* client, need to make sure lrc is pinned prior to enter here.
*/
if (!ce->state)
break; /* XXX: continue? */
lrc->context_desc = lower_32_bits(ce->lrc_desc);
/* The state page is after PPHWSP */
gfx_addr = i915_gem_obj_ggtt_offset(ce->state);
lrc->ring_lcra = gfx_addr + LRC_STATE_PN * PAGE_SIZE;
lrc->context_id = (client->ctx_index << GUC_ELC_CTXID_OFFSET) |
(engine->guc_id << GUC_ELC_ENGINE_OFFSET);
obj = ce->ringbuf->obj;
gfx_addr = i915_gem_obj_ggtt_offset(obj);
lrc->ring_begin = gfx_addr;
lrc->ring_end = gfx_addr + obj->base.size - 1;
lrc->ring_next_free_location = gfx_addr;
lrc->ring_current_tail_pointer_value = 0;
desc.engines_used |= (1 << engine->guc_id);
}
WARN_ON(desc.engines_used == 0);
/*
* The doorbell, process descriptor, and workqueue are all parts
* of the client object, which the GuC will reference via the GGTT
*/
gfx_addr = i915_gem_obj_ggtt_offset(client_obj);
desc.db_trigger_phy = sg_dma_address(client_obj->pages->sgl) +
client->doorbell_offset;
desc.db_trigger_cpu = (uintptr_t)client->client_base +
client->doorbell_offset;
desc.db_trigger_uk = gfx_addr + client->doorbell_offset;
desc.process_desc = gfx_addr + client->proc_desc_offset;
desc.wq_addr = gfx_addr + client->wq_offset;
desc.wq_size = client->wq_size;
/*
* XXX: Take LRCs from an existing context if this is not an
* IsKMDCreatedContext client
*/
desc.desc_private = (uintptr_t)client;
/* Pool context is pinned already */
sg = guc->ctx_pool_obj->pages;
sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
sizeof(desc) * client->ctx_index);
}
static void guc_fini_ctx_desc(struct intel_guc *guc,
struct i915_guc_client *client)
{
struct guc_context_desc desc;
struct sg_table *sg;
memset(&desc, 0, sizeof(desc));
sg = guc->ctx_pool_obj->pages;
sg_pcopy_from_buffer(sg->sgl, sg->nents, &desc, sizeof(desc),
sizeof(desc) * client->ctx_index);
}
/**
* i915_guc_wq_check_space() - check that the GuC can accept a request
* @request: request associated with the commands
*
* Return: 0 if space is available
* -EAGAIN if space is not currently available
*
* This function must be called (and must return 0) before a request
* is submitted to the GuC via i915_guc_submit() below. Once a result
* of 0 has been returned, it remains valid until (but only until)
* the next call to submit().
*
* This precheck allows the caller to determine in advance that space
* will be available for the next submission before committing resources
* to it, and helps avoid late failures with complicated recovery paths.
*/
int i915_guc_wq_check_space(struct drm_i915_gem_request *request)
{
const size_t wqi_size = sizeof(struct guc_wq_item);
struct i915_guc_client *gc = request->i915->guc.execbuf_client;
struct guc_process_desc *desc;
u32 freespace;
GEM_BUG_ON(gc == NULL);
desc = gc->client_base + gc->proc_desc_offset;
freespace = CIRC_SPACE(gc->wq_tail, desc->head, gc->wq_size);
if (likely(freespace >= wqi_size))
return 0;
gc->no_wq_space += 1;
return -EAGAIN;
}
static void guc_add_workqueue_item(struct i915_guc_client *gc,
struct drm_i915_gem_request *rq)
{
/* wqi_len is in DWords, and does not include the one-word header */
const size_t wqi_size = sizeof(struct guc_wq_item);
const u32 wqi_len = wqi_size/sizeof(u32) - 1;
struct guc_process_desc *desc;
struct guc_wq_item *wqi;
void *base;
u32 freespace, tail, wq_off, wq_page;
desc = gc->client_base + gc->proc_desc_offset;
/* Free space is guaranteed, see i915_guc_wq_check_space() above */
freespace = CIRC_SPACE(gc->wq_tail, desc->head, gc->wq_size);
GEM_BUG_ON(freespace < wqi_size);
/* The GuC firmware wants the tail index in QWords, not bytes */
tail = rq->tail;
GEM_BUG_ON(tail & 7);
tail >>= 3;
GEM_BUG_ON(tail > WQ_RING_TAIL_MAX);
/* For now workqueue item is 4 DWs; workqueue buffer is 2 pages. So we
* should not have the case where structure wqi is across page, neither
* wrapped to the beginning. This simplifies the implementation below.
*
* XXX: if not the case, we need save data to a temp wqi and copy it to
* workqueue buffer dw by dw.
*/
BUILD_BUG_ON(wqi_size != 16);
/* postincrement WQ tail for next time */
wq_off = gc->wq_tail;
gc->wq_tail += wqi_size;
gc->wq_tail &= gc->wq_size - 1;
GEM_BUG_ON(wq_off & (wqi_size - 1));
/* WQ starts from the page after doorbell / process_desc */
wq_page = (wq_off + GUC_DB_SIZE) >> PAGE_SHIFT;
wq_off &= PAGE_SIZE - 1;
base = kmap_atomic(i915_gem_object_get_page(gc->client_obj, wq_page));
wqi = (struct guc_wq_item *)((char *)base + wq_off);
/* Now fill in the 4-word work queue item */
wqi->header = WQ_TYPE_INORDER |
(wqi_len << WQ_LEN_SHIFT) |
(rq->engine->guc_id << WQ_TARGET_SHIFT) |
WQ_NO_WCFLUSH_WAIT;
/* The GuC wants only the low-order word of the context descriptor */
wqi->context_desc = (u32)intel_lr_context_descriptor(rq->ctx,
rq->engine);
wqi->ring_tail = tail << WQ_RING_TAIL_SHIFT;
wqi->fence_id = rq->seqno;
kunmap_atomic(base);
}
static int guc_ring_doorbell(struct i915_guc_client *gc)
{
struct guc_process_desc *desc;
union guc_doorbell_qw db_cmp, db_exc, db_ret;
union guc_doorbell_qw *db;
int attempt = 2, ret = -EAGAIN;
desc = gc->client_base + gc->proc_desc_offset;
/* Update the tail so it is visible to GuC */
desc->tail = gc->wq_tail;
/* current cookie */
db_cmp.db_status = GUC_DOORBELL_ENABLED;
db_cmp.cookie = gc->cookie;
/* cookie to be updated */
db_exc.db_status = GUC_DOORBELL_ENABLED;
db_exc.cookie = gc->cookie + 1;
if (db_exc.cookie == 0)
db_exc.cookie = 1;
/* pointer of current doorbell cacheline */
db = gc->client_base + gc->doorbell_offset;
while (attempt--) {
/* lets ring the doorbell */
db_ret.value_qw = atomic64_cmpxchg((atomic64_t *)db,
db_cmp.value_qw, db_exc.value_qw);
/* if the exchange was successfully executed */
if (db_ret.value_qw == db_cmp.value_qw) {
/* db was successfully rung */
gc->cookie = db_exc.cookie;
ret = 0;
break;
}
/* XXX: doorbell was lost and need to acquire it again */
if (db_ret.db_status == GUC_DOORBELL_DISABLED)
break;
DRM_ERROR("Cookie mismatch. Expected %d, returned %d\n",
db_cmp.cookie, db_ret.cookie);
/* update the cookie to newly read cookie from GuC */
db_cmp.cookie = db_ret.cookie;
db_exc.cookie = db_ret.cookie + 1;
if (db_exc.cookie == 0)
db_exc.cookie = 1;
}
return ret;
}
/**
* i915_guc_submit() - Submit commands through GuC
* @rq: request associated with the commands
*
* Return: 0 on success, otherwise an errno.
* (Note: nonzero really shouldn't happen!)
*
* The caller must have already called i915_guc_wq_check_space() above
* with a result of 0 (success) since the last request submission. This
* guarantees that there is space in the work queue for the new request,
* so enqueuing the item cannot fail.
*
* Bad Things Will Happen if the caller violates this protocol e.g. calls
* submit() when check() says there's no space, or calls submit() multiple
* times with no intervening check().
*
* The only error here arises if the doorbell hardware isn't functioning
* as expected, which really shouln't happen.
*/
int i915_guc_submit(struct drm_i915_gem_request *rq)
{
unsigned int engine_id = rq->engine->id;
struct intel_guc *guc = &rq->i915->guc;
struct i915_guc_client *client = guc->execbuf_client;
int b_ret;
guc_add_workqueue_item(client, rq);
b_ret = guc_ring_doorbell(client);
client->submissions[engine_id] += 1;
client->retcode = b_ret;
if (b_ret)
client->b_fail += 1;
guc->submissions[engine_id] += 1;
guc->last_seqno[engine_id] = rq->seqno;
return b_ret;
}
/*
* Everything below here is concerned with setup & teardown, and is
* therefore not part of the somewhat time-critical batch-submission
* path of i915_guc_submit() above.
*/
/**
* gem_allocate_guc_obj() - Allocate gem object for GuC usage
* @dev_priv: driver private data structure
* @size: size of object
*
* This is a wrapper to create a gem obj. In order to use it inside GuC, the
* object needs to be pinned lifetime. Also we must pin it to gtt space other
* than [0, GUC_WOPCM_TOP) because this range is reserved inside GuC.
*
* Return: A drm_i915_gem_object if successful, otherwise NULL.
*/
static struct drm_i915_gem_object *
gem_allocate_guc_obj(struct drm_i915_private *dev_priv, u32 size)
{
struct drm_i915_gem_object *obj;
obj = i915_gem_object_create(&dev_priv->drm, size);
if (IS_ERR(obj))
return NULL;
if (i915_gem_object_get_pages(obj)) {
drm_gem_object_unreference(&obj->base);
return NULL;
}
if (i915_gem_obj_ggtt_pin(obj, PAGE_SIZE,
PIN_OFFSET_BIAS | GUC_WOPCM_TOP)) {
drm_gem_object_unreference(&obj->base);
return NULL;
}
/* Invalidate GuC TLB to let GuC take the latest updates to GTT. */
I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
return obj;
}
/**
* gem_release_guc_obj() - Release gem object allocated for GuC usage
* @obj: gem obj to be released
*/
static void gem_release_guc_obj(struct drm_i915_gem_object *obj)
{
if (!obj)
return;
if (i915_gem_obj_is_pinned(obj))
i915_gem_object_ggtt_unpin(obj);
drm_gem_object_unreference(&obj->base);
}
static void
guc_client_free(struct drm_i915_private *dev_priv,
struct i915_guc_client *client)
{
struct intel_guc *guc = &dev_priv->guc;
if (!client)
return;
/*
* XXX: wait for any outstanding submissions before freeing memory.
* Be sure to drop any locks
*/
if (client->client_base) {
/*
* If we got as far as setting up a doorbell, make sure we
* shut it down before unmapping & deallocating the memory.
*/
guc_disable_doorbell(guc, client);
kunmap(kmap_to_page(client->client_base));
}
gem_release_guc_obj(client->client_obj);
if (client->ctx_index != GUC_INVALID_CTX_ID) {
guc_fini_ctx_desc(guc, client);
ida_simple_remove(&guc->ctx_ids, client->ctx_index);
}
kfree(client);
}
/*
* Borrow the first client to set up & tear down every doorbell
* in turn, to ensure that all doorbell h/w is (re)initialised.
*/
static void guc_init_doorbell_hw(struct intel_guc *guc)
{
struct drm_i915_private *dev_priv = guc_to_i915(guc);
struct i915_guc_client *client = guc->execbuf_client;
uint16_t db_id, i;
int err;
db_id = client->doorbell_id;
for (i = 0; i < GUC_MAX_DOORBELLS; ++i) {
i915_reg_t drbreg = GEN8_DRBREGL(i);
u32 value = I915_READ(drbreg);
err = guc_update_doorbell_id(guc, client, i);
/* Report update failure or unexpectedly active doorbell */
if (err || (i != db_id && (value & GUC_DOORBELL_ENABLED)))
DRM_DEBUG_DRIVER("Doorbell %d (reg 0x%x) was 0x%x, err %d\n",
i, drbreg.reg, value, err);
}
/* Restore to original value */
err = guc_update_doorbell_id(guc, client, db_id);
if (err)
DRM_ERROR("Failed to restore doorbell to %d, err %d\n",
db_id, err);
for (i = 0; i < GUC_MAX_DOORBELLS; ++i) {
i915_reg_t drbreg = GEN8_DRBREGL(i);
u32 value = I915_READ(drbreg);
if (i != db_id && (value & GUC_DOORBELL_ENABLED))
DRM_DEBUG_DRIVER("Doorbell %d (reg 0x%x) finally 0x%x\n",
i, drbreg.reg, value);
}
}
/**
* guc_client_alloc() - Allocate an i915_guc_client
* @dev_priv: driver private data structure
* @priority: four levels priority _CRITICAL, _HIGH, _NORMAL and _LOW
* The kernel client to replace ExecList submission is created with
* NORMAL priority. Priority of a client for scheduler can be HIGH,
* while a preemption context can use CRITICAL.
* @ctx: the context that owns the client (we use the default render
* context)
*
* Return: An i915_guc_client object if success, else NULL.
*/
static struct i915_guc_client *
guc_client_alloc(struct drm_i915_private *dev_priv,
uint32_t priority,
struct i915_gem_context *ctx)
{
struct i915_guc_client *client;
struct intel_guc *guc = &dev_priv->guc;
struct drm_i915_gem_object *obj;
uint16_t db_id;
client = kzalloc(sizeof(*client), GFP_KERNEL);
if (!client)
return NULL;
client->doorbell_id = GUC_INVALID_DOORBELL_ID;
client->priority = priority;
client->owner = ctx;
client->guc = guc;
client->ctx_index = (uint32_t)ida_simple_get(&guc->ctx_ids, 0,
GUC_MAX_GPU_CONTEXTS, GFP_KERNEL);
if (client->ctx_index >= GUC_MAX_GPU_CONTEXTS) {
client->ctx_index = GUC_INVALID_CTX_ID;
goto err;
}
/* The first page is doorbell/proc_desc. Two followed pages are wq. */
obj = gem_allocate_guc_obj(dev_priv, GUC_DB_SIZE + GUC_WQ_SIZE);
if (!obj)
goto err;
/* We'll keep just the first (doorbell/proc) page permanently kmap'd. */
client->client_obj = obj;
client->client_base = kmap(i915_gem_object_get_page(obj, 0));
client->wq_offset = GUC_DB_SIZE;
client->wq_size = GUC_WQ_SIZE;
db_id = select_doorbell_register(guc, client->priority);
if (db_id == GUC_INVALID_DOORBELL_ID)
/* XXX: evict a doorbell instead? */
goto err;
client->doorbell_offset = select_doorbell_cacheline(guc);
/*
* Since the doorbell only requires a single cacheline, we can save
* space by putting the application process descriptor in the same
* page. Use the half of the page that doesn't include the doorbell.
*/
if (client->doorbell_offset >= (GUC_DB_SIZE / 2))
client->proc_desc_offset = 0;
else
client->proc_desc_offset = (GUC_DB_SIZE / 2);
guc_init_proc_desc(guc, client);
guc_init_ctx_desc(guc, client);
if (guc_init_doorbell(guc, client, db_id))
goto err;
DRM_DEBUG_DRIVER("new priority %u client %p: ctx_index %u\n",
priority, client, client->ctx_index);
DRM_DEBUG_DRIVER("doorbell id %u, cacheline offset 0x%x\n",
client->doorbell_id, client->doorbell_offset);
return client;
err:
DRM_ERROR("FAILED to create priority %u GuC client!\n", priority);
guc_client_free(dev_priv, client);
return NULL;
}
static void guc_create_log(struct intel_guc *guc)
{
struct drm_i915_private *dev_priv = guc_to_i915(guc);
struct drm_i915_gem_object *obj;
unsigned long offset;
uint32_t size, flags;
if (i915.guc_log_level < GUC_LOG_VERBOSITY_MIN)
return;
if (i915.guc_log_level > GUC_LOG_VERBOSITY_MAX)
i915.guc_log_level = GUC_LOG_VERBOSITY_MAX;
/* The first page is to save log buffer state. Allocate one
* extra page for others in case for overlap */
size = (1 + GUC_LOG_DPC_PAGES + 1 +
GUC_LOG_ISR_PAGES + 1 +
GUC_LOG_CRASH_PAGES + 1) << PAGE_SHIFT;
obj = guc->log_obj;
if (!obj) {
obj = gem_allocate_guc_obj(dev_priv, size);
if (!obj) {
/* logging will be off */
i915.guc_log_level = -1;
return;
}
guc->log_obj = obj;
}
/* each allocated unit is a page */
flags = GUC_LOG_VALID | GUC_LOG_NOTIFY_ON_HALF_FULL |
(GUC_LOG_DPC_PAGES << GUC_LOG_DPC_SHIFT) |
(GUC_LOG_ISR_PAGES << GUC_LOG_ISR_SHIFT) |
(GUC_LOG_CRASH_PAGES << GUC_LOG_CRASH_SHIFT);
offset = i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT; /* in pages */
guc->log_flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
}
static void init_guc_policies(struct guc_policies *policies)
{
struct guc_policy *policy;
u32 p, i;
policies->dpc_promote_time = 500000;
policies->max_num_work_items = POLICY_MAX_NUM_WI;
for (p = 0; p < GUC_CTX_PRIORITY_NUM; p++) {
for (i = GUC_RENDER_ENGINE; i < GUC_MAX_ENGINES_NUM; i++) {
policy = &policies->policy[p][i];
policy->execution_quantum = 1000000;
policy->preemption_time = 500000;
policy->fault_time = 250000;
policy->policy_flags = 0;
}
}
policies->is_valid = 1;
}
static void guc_create_ads(struct intel_guc *guc)
{
struct drm_i915_private *dev_priv = guc_to_i915(guc);
struct drm_i915_gem_object *obj;
struct guc_ads *ads;
struct guc_policies *policies;
struct guc_mmio_reg_state *reg_state;
struct intel_engine_cs *engine;
struct page *page;
u32 size;
/* The ads obj includes the struct itself and buffers passed to GuC */
size = sizeof(struct guc_ads) + sizeof(struct guc_policies) +
sizeof(struct guc_mmio_reg_state) +
GUC_S3_SAVE_SPACE_PAGES * PAGE_SIZE;
obj = guc->ads_obj;
if (!obj) {
obj = gem_allocate_guc_obj(dev_priv, PAGE_ALIGN(size));
if (!obj)
return;
guc->ads_obj = obj;
}
page = i915_gem_object_get_page(obj, 0);
ads = kmap(page);
/*
* The GuC requires a "Golden Context" when it reinitialises
* engines after a reset. Here we use the Render ring default
* context, which must already exist and be pinned in the GGTT,
* so its address won't change after we've told the GuC where
* to find it.
*/
engine = &dev_priv->engine[RCS];
ads->golden_context_lrca = engine->status_page.gfx_addr;
for_each_engine(engine, dev_priv)
ads->eng_state_size[engine->guc_id] = intel_lr_context_size(engine);
/* GuC scheduling policies */
policies = (void *)ads + sizeof(struct guc_ads);
init_guc_policies(policies);
ads->scheduler_policies = i915_gem_obj_ggtt_offset(obj) +
sizeof(struct guc_ads);
/* MMIO reg state */
reg_state = (void *)policies + sizeof(struct guc_policies);
for_each_engine(engine, dev_priv) {
reg_state->mmio_white_list[engine->guc_id].mmio_start =
engine->mmio_base + GUC_MMIO_WHITE_LIST_START;
/* Nothing to be saved or restored for now. */
reg_state->mmio_white_list[engine->guc_id].count = 0;
}
ads->reg_state_addr = ads->scheduler_policies +
sizeof(struct guc_policies);
ads->reg_state_buffer = ads->reg_state_addr +
sizeof(struct guc_mmio_reg_state);
kunmap(page);
}
/*
* Set up the memory resources to be shared with the GuC. At this point,
* we require just one object that can be mapped through the GGTT.
*/
int i915_guc_submission_init(struct drm_i915_private *dev_priv)
{
const size_t ctxsize = sizeof(struct guc_context_desc);
const size_t poolsize = GUC_MAX_GPU_CONTEXTS * ctxsize;
const size_t gemsize = round_up(poolsize, PAGE_SIZE);
struct intel_guc *guc = &dev_priv->guc;
/* Wipe bitmap & delete client in case of reinitialisation */
bitmap_clear(guc->doorbell_bitmap, 0, GUC_MAX_DOORBELLS);
i915_guc_submission_disable(dev_priv);
if (!i915.enable_guc_submission)
return 0; /* not enabled */
if (guc->ctx_pool_obj)
return 0; /* already allocated */
guc->ctx_pool_obj = gem_allocate_guc_obj(dev_priv, gemsize);
if (!guc->ctx_pool_obj)
return -ENOMEM;
ida_init(&guc->ctx_ids);
guc_create_log(guc);
guc_create_ads(guc);
return 0;
}
int i915_guc_submission_enable(struct drm_i915_private *dev_priv)
{
struct intel_guc *guc = &dev_priv->guc;
struct i915_guc_client *client;
/* client for execbuf submission */
client = guc_client_alloc(dev_priv,
GUC_CTX_PRIORITY_KMD_NORMAL,
dev_priv->kernel_context);
if (!client) {
DRM_ERROR("Failed to create execbuf guc_client\n");
return -ENOMEM;
}
guc->execbuf_client = client;
host2guc_sample_forcewake(guc, client);
guc_init_doorbell_hw(guc);
return 0;
}
void i915_guc_submission_disable(struct drm_i915_private *dev_priv)
{
struct intel_guc *guc = &dev_priv->guc;
guc_client_free(dev_priv, guc->execbuf_client);
guc->execbuf_client = NULL;
}
void i915_guc_submission_fini(struct drm_i915_private *dev_priv)
{
struct intel_guc *guc = &dev_priv->guc;
gem_release_guc_obj(dev_priv->guc.ads_obj);
guc->ads_obj = NULL;
gem_release_guc_obj(dev_priv->guc.log_obj);
guc->log_obj = NULL;
if (guc->ctx_pool_obj)
ida_destroy(&guc->ctx_ids);
gem_release_guc_obj(guc->ctx_pool_obj);
guc->ctx_pool_obj = NULL;
}
/**
* intel_guc_suspend() - notify GuC entering suspend state
* @dev: drm device
*/
int intel_guc_suspend(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = to_i915(dev);
struct intel_guc *guc = &dev_priv->guc;
struct i915_gem_context *ctx;
u32 data[3];
if (guc->guc_fw.guc_fw_load_status != GUC_FIRMWARE_SUCCESS)
return 0;
ctx = dev_priv->kernel_context;
data[0] = HOST2GUC_ACTION_ENTER_S_STATE;
/* any value greater than GUC_POWER_D0 */
data[1] = GUC_POWER_D1;
/* first page is shared data with GuC */
data[2] = i915_gem_obj_ggtt_offset(ctx->engine[RCS].state);
return host2guc_action(guc, data, ARRAY_SIZE(data));
}
/**
* intel_guc_resume() - notify GuC resuming from suspend state
* @dev: drm device
*/
int intel_guc_resume(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = to_i915(dev);
struct intel_guc *guc = &dev_priv->guc;
struct i915_gem_context *ctx;
u32 data[3];
if (guc->guc_fw.guc_fw_load_status != GUC_FIRMWARE_SUCCESS)
return 0;
ctx = dev_priv->kernel_context;
data[0] = HOST2GUC_ACTION_EXIT_S_STATE;
data[1] = GUC_POWER_D0;
/* first page is shared data with GuC */
data[2] = i915_gem_obj_ggtt_offset(ctx->engine[RCS].state);
return host2guc_action(guc, data, ARRAY_SIZE(data));
}
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