6.15-stable review patch. If anyone has any objections, please let me know.
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From: Zhi Wang zhiw@nvidia.com
commit a738fa9105ac2897701ba4067c33e85faa27d1e2 upstream.
Some GSP RPC commands need a new reply policy: "caller don't care about the message content but want to make sure a reply is received". To support this case, a new reply policy is introduced.
NV_VGPU_MSG_FUNCTION_ALLOC_MEMORY is a large GSP RPC command. The actual required policy is NVKM_GSP_RPC_REPLY_POLL. This can be observed from the dump of the GSP message queue. After the large GSP RPC command is issued, GSP will write only an empty RPC header in the queue as the reply.
Without this change, the policy "receiving the entire message" is used for NV_VGPU_MSG_FUNCTION_ALLOC_MEMORY. This causes the timeout of receiving the returned GSP message in the suspend/resume path.
Introduce the new reply policy NVKM_GSP_RPC_REPLY_POLL, which waits for the returned GSP message but discards it for the caller. Use the new policy NVKM_GSP_RPC_REPLY_POLL on the GSP RPC command NV_VGPU_MSG_FUNCTION_ALLOC_MEMORY.
Fixes: 50f290053d79 ("drm/nouveau: support handling the return of large GSP message") Cc: Danilo Krummrich dakr@kernel.org Cc: Alexandre Courbot acourbot@nvidia.com Tested-by: Ben Skeggs bskeggs@nvidia.com Signed-off-by: Zhi Wang zhiw@nvidia.com Signed-off-by: Danilo Krummrich dakr@kernel.org Link: https://patchwork.freedesktop.org/patch/msgid/20250227013554.8269-3-zhiw@nvi... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h | 4 ++++ drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c | 3 +++ drivers/gpu/drm/nouveau/nvkm/subdev/instmem/r535.c | 2 +- 3 files changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h +++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/gsp.h @@ -44,10 +44,14 @@ typedef void (*nvkm_gsp_event_func)(stru * NVKM_GSP_RPC_REPLY_RECV - If specified, wait and receive the entire GSP * RPC message after the GSP RPC command is issued. * + * NVKM_GSP_RPC_REPLY_POLL - If specified, wait for the specific reply and + * discard the reply before returning to the caller. + * */ enum nvkm_gsp_rpc_reply_policy { NVKM_GSP_RPC_REPLY_NOWAIT = 0, NVKM_GSP_RPC_REPLY_RECV, + NVKM_GSP_RPC_REPLY_POLL, };
struct nvkm_gsp { --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c @@ -602,6 +602,9 @@ r535_gsp_rpc_handle_reply(struct nvkm_gs else repv = reply; break; + case NVKM_GSP_RPC_REPLY_POLL: + repv = r535_gsp_msg_recv(gsp, fn, 0); + break; }
return repv; --- a/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/r535.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/r535.c @@ -105,7 +105,7 @@ fbsr_memlist(struct nvkm_gsp_device *dev rpc->pteDesc.pte_pde[i].pte = (phys >> 12) + i; }
- ret = nvkm_gsp_rpc_wr(gsp, rpc, NVKM_GSP_RPC_REPLY_RECV); + ret = nvkm_gsp_rpc_wr(gsp, rpc, NVKM_GSP_RPC_REPLY_POLL); if (ret) return ret;