From: Hersen Wu Date: Mon, 23 Apr 2018 19:21:45 -0400 Subject: drm/amd/display: AUX will exit when HPD LOW detected Git-commit: 73770ca53f63489b32175ab8b5ddd4632b747275 Patch-mainline: v4.19-rc1 References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166 This change shorten wait time when HPD LOW. With HPD LOW, without this change, AUX routine delay is 450us. With this change, it is 42us. Signed-off-by: Hersen Wu Reviewed-by: Tony Cheng Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher Acked-by: Petr Tesarik --- drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.c | 16 +++++++ drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h | 5 +- drivers/gpu/drm/amd/display/dc/i2caux/dce110/aux_engine_dce110.c | 22 +++++++--- drivers/gpu/drm/amd/display/dc/i2caux/engine.h | 3 - drivers/gpu/drm/amd/display/include/ddc_service_types.h | 3 - 5 files changed, 41 insertions(+), 8 deletions(-) --- a/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.c +++ b/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.c @@ -157,6 +157,10 @@ static void process_read_reply( ctx->operation_succeeded = false; } break; + case AUX_TRANSACTION_REPLY_HPD_DISCON: + ctx->status = I2CAUX_TRANSACTION_STATUS_FAILED_HPD_DISCON; + ctx->operation_succeeded = false; + break; default: ctx->status = I2CAUX_TRANSACTION_STATUS_UNKNOWN; ctx->operation_succeeded = false; @@ -215,6 +219,10 @@ static void process_read_request( * so we should not wait here */ } break; + case AUX_CHANNEL_OPERATION_FAILED_HPD_DISCON: + ctx->status = I2CAUX_TRANSACTION_STATUS_FAILED_HPD_DISCON; + ctx->operation_succeeded = false; + break; default: ctx->status = I2CAUX_TRANSACTION_STATUS_UNKNOWN; ctx->operation_succeeded = false; @@ -370,6 +378,10 @@ static void process_write_reply( ctx->operation_succeeded = false; } break; + case AUX_TRANSACTION_REPLY_HPD_DISCON: + ctx->status = I2CAUX_TRANSACTION_STATUS_FAILED_HPD_DISCON; + ctx->operation_succeeded = false; + break; default: ctx->status = I2CAUX_TRANSACTION_STATUS_UNKNOWN; ctx->operation_succeeded = false; @@ -422,6 +434,10 @@ static void process_write_request( * so we should not wait here */ } break; + case AUX_CHANNEL_OPERATION_FAILED_HPD_DISCON: + ctx->status = I2CAUX_TRANSACTION_STATUS_FAILED_HPD_DISCON; + ctx->operation_succeeded = false; + break; default: ctx->status = I2CAUX_TRANSACTION_STATUS_UNKNOWN; ctx->operation_succeeded = false; --- a/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h +++ b/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h @@ -51,6 +51,8 @@ enum aux_transaction_reply { AUX_TRANSACTION_REPLY_I2C_NACK = 0x10, AUX_TRANSACTION_REPLY_I2C_DEFER = 0x20, + AUX_TRANSACTION_REPLY_HPD_DISCON = 0x40, + AUX_TRANSACTION_REPLY_INVALID = 0xFF }; @@ -64,7 +66,8 @@ enum aux_channel_operation_result { AUX_CHANNEL_OPERATION_SUCCEEDED, AUX_CHANNEL_OPERATION_FAILED_REASON_UNKNOWN, AUX_CHANNEL_OPERATION_FAILED_INVALID_REPLY, - AUX_CHANNEL_OPERATION_FAILED_TIMEOUT + AUX_CHANNEL_OPERATION_FAILED_TIMEOUT, + AUX_CHANNEL_OPERATION_FAILED_HPD_DISCON }; struct aux_engine; --- a/drivers/gpu/drm/amd/display/dc/i2caux/dce110/aux_engine_dce110.c +++ b/drivers/gpu/drm/amd/display/dc/i2caux/dce110/aux_engine_dce110.c @@ -291,6 +291,12 @@ static void process_channel_reply( value = REG_GET(AUX_SW_STATUS, AUX_SW_REPLY_BYTE_COUNT, &bytes_replied); + /* in case HPD is LOW, exit AUX transaction */ + if ((value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) { + reply->status = AUX_TRANSACTION_REPLY_HPD_DISCON; + return; + } + if (bytes_replied) { uint32_t reply_result; @@ -347,8 +353,10 @@ static void process_channel_reply( * because there was surely an error that was asserted * that should have been handled * for hot plug case, this could happens*/ - if (!(value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) + if (!(value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) { + reply->status = AUX_TRANSACTION_REPLY_INVALID; ASSERT_CRITICAL(false); + } } } @@ -371,6 +379,10 @@ static enum aux_channel_operation_result value = REG_WAIT(AUX_SW_STATUS, AUX_SW_DONE, 1, 10, aux110->timeout_period/10); + /* in case HPD is LOW, exit AUX transaction */ + if ((value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) + return AUX_CHANNEL_OPERATION_FAILED_HPD_DISCON; + /* Note that the following bits are set in 'status.bits' * during CTS 4.2.1.2 (FW 3.3.1): * AUX_SW_RX_MIN_COUNT_VIOL, AUX_SW_RX_INVALID_STOP, @@ -402,10 +414,10 @@ static enum aux_channel_operation_result return AUX_CHANNEL_OPERATION_SUCCEEDED; } } else { - /*time_elapsed >= aux_engine->timeout_period */ - if (!(value & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) - ASSERT_CRITICAL(false); - + /*time_elapsed >= aux_engine->timeout_period + * AUX_SW_STATUS__AUX_SW_HPD_DISCON = at this point + */ + ASSERT_CRITICAL(false); return AUX_CHANNEL_OPERATION_FAILED_TIMEOUT; } } --- a/drivers/gpu/drm/amd/display/dc/i2caux/engine.h +++ b/drivers/gpu/drm/amd/display/dc/i2caux/engine.h @@ -53,7 +53,8 @@ enum i2caux_transaction_status { I2CAUX_TRANSACTION_STATUS_FAILED_INCOMPLETE, I2CAUX_TRANSACTION_STATUS_FAILED_OPERATION, I2CAUX_TRANSACTION_STATUS_FAILED_INVALID_OPERATION, - I2CAUX_TRANSACTION_STATUS_FAILED_BUFFER_OVERFLOW + I2CAUX_TRANSACTION_STATUS_FAILED_BUFFER_OVERFLOW, + I2CAUX_TRANSACTION_STATUS_FAILED_HPD_DISCON }; struct i2caux_transaction_request { --- a/drivers/gpu/drm/amd/display/include/ddc_service_types.h +++ b/drivers/gpu/drm/amd/display/include/ddc_service_types.h @@ -40,7 +40,8 @@ enum ddc_result { DDC_RESULT_FAILED_INCOMPLETE, DDC_RESULT_FAILED_OPERATION, DDC_RESULT_FAILED_INVALID_OPERATION, - DDC_RESULT_FAILED_BUFFER_OVERFLOW + DDC_RESULT_FAILED_BUFFER_OVERFLOW, + DDC_RESULT_FAILED_HPD_DISCON }; enum ddc_service_type {