diff options
Diffstat (limited to 'drivers/gpu/drm/xe/abi/guc_communication_ctb_abi.h')
| -rw-r--r-- | drivers/gpu/drm/xe/abi/guc_communication_ctb_abi.h | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/abi/guc_communication_ctb_abi.h b/drivers/gpu/drm/xe/abi/guc_communication_ctb_abi.h new file mode 100644 index 000000000000..41244055cc0c --- /dev/null +++ b/drivers/gpu/drm/xe/abi/guc_communication_ctb_abi.h @@ -0,0 +1,189 @@ +/* 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> +#include <linux/build_bug.h> + +#include "guc_messages_abi.h" + +/** + * DOC: CT Buffer + * + * Circular buffer used to send `CTB Message`_ + */ + +/** + * DOC: CTB Descriptor + * + * +---+-------+--------------------------------------------------------------+ + * | | Bits | Description | + * +===+=======+==============================================================+ + * | 0 | 31:0 | **HEAD** - offset (in dwords) to the last dword that was | + * | | | read from the `CT Buffer`_. | + * | | | It can only be updated by the receiver. | + * +---+-------+--------------------------------------------------------------+ + * | 1 | 31:0 | **TAIL** - offset (in dwords) to the last dword that was | + * | | | written to the `CT Buffer`_. | + * | | | It can only be updated by the sender. | + * +---+-------+--------------------------------------------------------------+ + * | 2 | 31:0 | **STATUS** - status of the CTB | + * | | | | + * | | | - _`GUC_CTB_STATUS_NO_ERROR` = 0 (normal operation) | + * | | | - _`GUC_CTB_STATUS_OVERFLOW` = 1 (head/tail too large) | + * | | | - _`GUC_CTB_STATUS_UNDERFLOW` = 2 (truncated message) | + * | | | - _`GUC_CTB_STATUS_MISMATCH` = 4 (head/tail modified) | + * +---+-------+--------------------------------------------------------------+ + * |...| | RESERVED = MBZ | + * +---+-------+--------------------------------------------------------------+ + * | 15| 31:0 | RESERVED = MBZ | + * +---+-------+--------------------------------------------------------------+ + */ + +struct guc_ct_buffer_desc { + u32 head; + u32 tail; + u32 status; +#define GUC_CTB_STATUS_NO_ERROR 0 +#define GUC_CTB_STATUS_OVERFLOW (1 << 0) +#define GUC_CTB_STATUS_UNDERFLOW (1 << 1) +#define GUC_CTB_STATUS_MISMATCH (1 << 2) + u32 reserved[13]; +} __packed; +static_assert(sizeof(struct guc_ct_buffer_desc) == 64); + +/** + * DOC: CTB Message + * + * +---+-------+--------------------------------------------------------------+ + * | | Bits | Description | + * +===+=======+==============================================================+ + * | 0 | 31:16 | **FENCE** - message identifier | + * | +-------+--------------------------------------------------------------+ + * | | 15:12 | **FORMAT** - format of the CTB message | + * | | | - _`GUC_CTB_FORMAT_HXG` = 0 - see `CTB HXG Message`_ | + * | +-------+--------------------------------------------------------------+ + * | | 11:8 | **RESERVED** | + * | +-------+--------------------------------------------------------------+ + * | | 7:0 | **NUM_DWORDS** - length of the CTB message (w/o header) | + * +---+-------+--------------------------------------------------------------+ + * | 1 | 31:0 | optional (depends on FORMAT) | + * +---+-------+ | + * |...| | | + * +---+-------+ | + * | n | 31:0 | | + * +---+-------+--------------------------------------------------------------+ + */ + +#define GUC_CTB_HDR_LEN 1u +#define GUC_CTB_MSG_MIN_LEN GUC_CTB_HDR_LEN +#define GUC_CTB_MSG_MAX_LEN 256u +#define GUC_CTB_MSG_0_FENCE (0xffff << 16) +#define GUC_CTB_MSG_0_FORMAT (0xf << 12) +#define GUC_CTB_FORMAT_HXG 0u +#define GUC_CTB_MSG_0_RESERVED (0xf << 8) +#define GUC_CTB_MSG_0_NUM_DWORDS (0xff << 0) + +/** + * DOC: CTB HXG Message + * + * +---+-------+--------------------------------------------------------------+ + * | | Bits | Description | + * +===+=======+==============================================================+ + * | 0 | 31:16 | FENCE | + * | +-------+--------------------------------------------------------------+ + * | | 15:12 | FORMAT = GUC_CTB_FORMAT_HXG_ | + * | +-------+--------------------------------------------------------------+ + * | | 11:8 | RESERVED = MBZ | + * | +-------+--------------------------------------------------------------+ + * | | 7:0 | NUM_DWORDS = length (in dwords) of the embedded HXG message | + * +---+-------+--------------------------------------------------------------+ + * | 1 | 31:0 | | + * +---+-------+ | + * |...| | [Embedded `HXG Message`_] | + * +---+-------+ | + * | n | 31:0 | | + * +---+-------+--------------------------------------------------------------+ + */ + +#define GUC_CTB_HXG_MSG_MIN_LEN (GUC_CTB_MSG_MIN_LEN + GUC_HXG_MSG_MIN_LEN) +#define GUC_CTB_HXG_MSG_MAX_LEN GUC_CTB_MSG_MAX_LEN + +/** + * 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 + */ + +/* + * 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 |