Prepare the data structures and completion wait helpers required for AIE4 command submission: - Define struct amdxdna_cmd_start_dpu in amdxdna_ctx.h for the ERT_START_DPU payload. - Extend union amdxdna_job_priv with an aie4 member for queue list linkage and job state tracking. - Implement smp_rmb() ordering and non-sleeping retry in get_read_index(), returning zero (no completion) when the sample is still invalid after the retry. - Update check_cmd_done() and aie4_cmd_wait() to detect asynchronous device disconnect and reset via check_cert_comp_linked().
get_read_index() returns 0 for an invalid sample. Since 0 <= any sequence number, callers never treat it as a completion. If this happens while the context is disconnected, aie4_cmd_wait() returns -EAGAIN so the caller retries the wait until a valid read_index is observed; the command state and fence are not affected. Co-developed-by: Max Zhen <[email protected]> Signed-off-by: Max Zhen <[email protected]> Co-developed-by: Wendy Liang <[email protected]> Signed-off-by: Wendy Liang <[email protected]> Signed-off-by: David Zhang <[email protected]> --- drivers/accel/amdxdna/aie4_ctx.c | 58 ++++++++++++++++++++--------- drivers/accel/amdxdna/amdxdna_ctx.h | 20 ++++++++++ 2 files changed, 60 insertions(+), 18 deletions(-) diff --git a/drivers/accel/amdxdna/aie4_ctx.c b/drivers/accel/amdxdna/aie4_ctx.c index 226570367f71..09c92b1b5134 100644 --- a/drivers/accel/amdxdna/aie4_ctx.c +++ b/drivers/accel/amdxdna/aie4_ctx.c @@ -394,34 +394,46 @@ static inline bool valid_queue_index(u64 read, u64 write, u32 capacity) static u64 get_read_index(struct amdxdna_hwctx *hwctx) { - u64 wi = READ_ONCE(*hwctx->priv->umq_write_index); - u64 ri = READ_ONCE(*hwctx->priv->umq_read_index); + struct amdxdna_hwctx_priv *priv = hwctx->priv; struct amdxdna_dev *xdna = hwctx->client->xdna; + u64 ri, wi; + + /* Sample read_index before write_index to guarantee wi >= ri. */ + ri = READ_ONCE(*priv->umq_read_index); + /* Order the read_index sample before the write_index sample. */ + smp_rmb(); + wi = READ_ONCE(priv->write_index); - /* - * CERT cannot update read index as uint64 atomically. Driver may read - * half-updated read index when it has bits in high 32bit. In case read - * index is not valid, wait for some time and retry once. It should - * allow CERT to complete the read index update. - */ + /* Non-atomic 64-bit counter update by CERT; re-sample once if invalid. */ if (!valid_queue_index(ri, wi, CTX_MAX_CMDS)) { - XDNA_WARN(xdna, "Invalid index, ri %llu, wi %llu", ri, wi); - usleep_range(100, 200); - ri = READ_ONCE(*hwctx->priv->umq_read_index); + ri = READ_ONCE(*priv->umq_read_index); + /* Order the read_index sample before the write_index sample. */ + smp_rmb(); + wi = READ_ONCE(priv->write_index); if (!valid_queue_index(ri, wi, CTX_MAX_CMDS)) { - XDNA_ERR(xdna, "Invalid index after retry, ri %llu, wi %llu", ri, wi); - ri = 0; + /* 0 <= any seq: callers always treat it as "not done" and retry. */ + XDNA_DBG(xdna, "Invalid index, ri %llu, wi %llu", ri, wi); + return 0; } } return ri; } -static inline bool check_cmd_done(struct amdxdna_hwctx *hwctx, u64 seq) +/* Verify cert_comp remains linked to detect disconnect or reset. */ +static bool check_cert_comp_linked(struct amdxdna_hwctx *hwctx, struct cert_comp *comp) +{ + /* READ_ONCE pairs with the link/unlink WRITE_ONCE. */ + return comp == READ_ONCE(hwctx->priv->cert_comp); +} + +static inline bool check_cmd_done(struct amdxdna_hwctx *hwctx, u64 seq, struct cert_comp *comp) { - u64 read_idx = get_read_index(hwctx); + /* Lockless check for wait_event condition; detects completion or disconnect. */ + if (!check_cert_comp_linked(hwctx, comp)) + return true; - return read_idx > seq; + return get_read_index(hwctx) > seq; } int aie4_cmd_wait(struct amdxdna_hwctx *hwctx, u64 seq, u32 timeout) @@ -437,11 +449,21 @@ int aie4_cmd_wait(struct amdxdna_hwctx *hwctx, u64 seq, u32 timeout) wait_jifs = msecs_to_jiffies(timeout); ret = wait_event_interruptible_timeout(cert_comp->waitq, - (check_cmd_done(hwctx, seq)), + check_cmd_done(hwctx, seq, cert_comp), wait_jifs); - if (!ret) + if (!ret) { ret = -ETIME; + } else if (ret > 0 && !check_cert_comp_linked(hwctx, cert_comp) && + get_read_index(hwctx) <= seq) { + /* + * Disconnected, or read_index invalid (0), before completion was + * seen. -EAGAIN is by design: the caller retries the wait until a + * valid read_index is observed. Command state and fence are not + * affected. + */ + ret = -EAGAIN; + } aie4_put_cert_comp(cert_comp); diff --git a/drivers/accel/amdxdna/amdxdna_ctx.h b/drivers/accel/amdxdna/amdxdna_ctx.h index 9bbc3db4ebde..b3677851d1c5 100644 --- a/drivers/accel/amdxdna/amdxdna_ctx.h +++ b/drivers/accel/amdxdna/amdxdna_ctx.h @@ -48,6 +48,18 @@ struct amdxdna_cmd_start_npu { u32 prop_args[]; /* properties and regular kernel arguments */ }; +/* + * struct amdxdna_cmd_start_dpu - interpretation of data payload for + * ERT_START_DPU in amdxdna_cmd. + */ +struct amdxdna_cmd_start_dpu { + u64 dtrace_buffer; /* dtrace buffer address 2 words */ + u64 instruction_buffer; /* buffer address 2 words */ + u32 instruction_buffer_size; /* size of buffer in bytes */ + u16 uc_index; /* microblaze controller index */ + u16 chained; /* number of following amdxdna_cmd_start_dpu elements */ +}; + /* * Interpretation of the beginning of data payload for ERT_CMD_CHAIN in * amdxdna_cmd. The rest of the payload in amdxdna_cmd is cmd BO handles. @@ -138,8 +150,14 @@ struct amdxdna_drv_cmd { }; struct app_health_report; + union amdxdna_job_priv { struct app_health_report *aie2_health; + /* aie4 kernel submission: queue linkage + job state */ + struct { + struct list_head list; + u32 state; + } aie4; }; struct amdxdna_sched_job { @@ -162,6 +180,8 @@ struct amdxdna_sched_job { }; #define aie2_job_health priv.aie2_health +#define aie4_job_list priv.aie4.list +#define aie4_job_state priv.aie4.state static inline u32 amdxdna_cmd_get_op(struct amdxdna_gem_obj *abo) -- 2.34.1
