diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h')
-rw-r--r-- | drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h b/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h new file mode 100644 index 000000000000..d38935f47ecf --- /dev/null +++ b/drivers/gpu/drm/i915/gt/uc/abi/guc_communication_ctb_abi.h @@ -0,0 +1,106 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2014-2021 Intel Corporation + */ + +#ifndef _ABI_GUC_COMMUNICATION_CTB_ABI_H +#define _ABI_GUC_COMMUNICATION_CTB_ABI_H + +#include <linux/types.h> + +/** + * DOC: CTB based communication + * + * The CTB (command transport buffer) communication between Host and GuC + * is based on u32 data stream written to the shared buffer. One buffer can + * be used to transmit data only in one direction (one-directional channel). + * + * Current status of the each buffer is stored in the buffer descriptor. + * Buffer descriptor holds tail and head fields that represents active data + * stream. The tail field is updated by the data producer (sender), and head + * field is updated by the data consumer (receiver):: + * + * +------------+ + * | DESCRIPTOR | +=================+============+========+ + * +============+ | | MESSAGE(s) | | + * | address |--------->+=================+============+========+ + * +------------+ + * | head | ^-----head--------^ + * +------------+ + * | tail | ^---------tail-----------------^ + * +------------+ + * | size | ^---------------size--------------------^ + * +------------+ + * + * Each message in data stream starts with the single u32 treated as a header, + * followed by optional set of u32 data that makes message specific payload:: + * + * +------------+---------+---------+---------+ + * | MESSAGE | + * +------------+---------+---------+---------+ + * | msg[0] | [1] | ... | [n-1] | + * +------------+---------+---------+---------+ + * | MESSAGE | MESSAGE PAYLOAD | + * + HEADER +---------+---------+---------+ + * | | 0 | ... | n | + * +======+=====+=========+=========+=========+ + * | 31:16| code| | | | + * +------+-----+ | | | + * | 15:5|flags| | | | + * +------+-----+ | | | + * | 4:0| len| | | | + * +------+-----+---------+---------+---------+ + * + * ^-------------len-------------^ + * + * The message header consists of: + * + * - **len**, indicates length of the message payload (in u32) + * - **code**, indicates message code + * - **flags**, holds various bits to control message handling + */ + +/* + * Describes single command transport buffer. + * Used by both guc-master and clients. + */ +struct guc_ct_buffer_desc { + u32 addr; /* gfx address */ + u64 host_private; /* host private data */ + u32 size; /* size in bytes */ + u32 head; /* offset updated by GuC*/ + u32 tail; /* offset updated by owner */ + u32 is_in_error; /* error indicator */ + u32 reserved1; + u32 reserved2; + u32 owner; /* id of the channel owner */ + u32 owner_sub_id; /* owner-defined field for extra tracking */ + u32 reserved[5]; +} __packed; + +/* Type of command transport buffer */ +#define INTEL_GUC_CT_BUFFER_TYPE_SEND 0x0u +#define INTEL_GUC_CT_BUFFER_TYPE_RECV 0x1u + +/* + * Definition of the command transport message header (DW0) + * + * bit[4..0] message len (in dwords) + * bit[7..5] reserved + * bit[8] response (G2H only) + * bit[8] write fence to desc (H2G only) + * bit[9] write status to H2G buff (H2G only) + * bit[10] send status back via G2H (H2G only) + * bit[15..11] reserved + * bit[31..16] action code + */ +#define GUC_CT_MSG_LEN_SHIFT 0 +#define GUC_CT_MSG_LEN_MASK 0x1F +#define GUC_CT_MSG_IS_RESPONSE (1 << 8) +#define GUC_CT_MSG_WRITE_FENCE_TO_DESC (1 << 8) +#define GUC_CT_MSG_WRITE_STATUS_TO_BUFF (1 << 9) +#define GUC_CT_MSG_SEND_STATUS (1 << 10) +#define GUC_CT_MSG_ACTION_SHIFT 16 +#define GUC_CT_MSG_ACTION_MASK 0xFFFF + +#endif /* _ABI_GUC_COMMUNICATION_CTB_ABI_H */ |