From 462e24fa4f1c1af6bd5ee845d2f757fcd1b8dec9 Mon Sep 17 00:00:00 2001 From: Harry Wentland Date: Tue, 8 May 2018 16:28:31 -0400 Subject: [PATCH 4908/5725] drm/amd/display: Break out function to simply read aux reply DRM's DP helpers take care of dealing with the error code for us. In order not to step on each other's toes we'll need to be able to simply read auch channel replies without further logic based on return values. Signed-off-by: Harry Wentland Reviewed-by: Sun peng Li Acked-by: Harry Wentland Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h | 6 ++ .../display/dc/i2caux/dce110/aux_engine_dce110.c | 119 ++++++++++++--------- 2 files changed, 76 insertions(+), 49 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h b/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h index b01488f..c33a289 100644 --- a/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h +++ b/drivers/gpu/drm/amd/display/dc/i2caux/aux_engine.h @@ -44,6 +44,12 @@ struct aux_engine_funcs { void (*process_channel_reply)( struct aux_engine *engine, struct aux_reply_transaction_data *reply); + int (*read_channel_reply)( + struct aux_engine *engine, + uint32_t size, + uint8_t *buffer, + uint8_t *reply_result, + uint32_t *sw_status); enum aux_channel_operation_result (*get_channel_status)( struct aux_engine *engine, uint8_t *returned_bytes); diff --git 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 index 2b927f2..1f39406 100644 --- 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 @@ -275,61 +275,92 @@ static void submit_channel_request( REG_UPDATE(AUX_SW_CONTROL, AUX_SW_GO, 1); } -static void process_channel_reply( - struct aux_engine *engine, - struct aux_reply_transaction_data *reply) +static int read_channel_reply(struct aux_engine *engine, uint32_t size, + uint8_t *buffer, uint8_t *reply_result, + uint32_t *sw_status) { struct aux_engine_dce110 *aux110 = FROM_AUX_ENGINE(engine); + uint32_t bytes_replied; + uint32_t reply_result_32; - /* Need to do a read to get the number of bytes to process - * Alternatively, this information can be passed - - * but that causes coupling which isn't good either. */ + *sw_status = REG_GET(AUX_SW_STATUS, AUX_SW_REPLY_BYTE_COUNT, + &bytes_replied); - uint32_t bytes_replied; - uint32_t value; + /* In case HPD is LOW, exit AUX transaction */ + if ((*sw_status & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) + return -1; - value = REG_GET(AUX_SW_STATUS, - AUX_SW_REPLY_BYTE_COUNT, &bytes_replied); + /* Need at least the status byte */ + if (!bytes_replied) + return -1; - /* 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; - } + REG_UPDATE_1BY1_3(AUX_SW_DATA, + AUX_SW_INDEX, 0, + AUX_SW_AUTOINCREMENT_DISABLE, 1, + AUX_SW_DATA_RW, 1); + + REG_GET(AUX_SW_DATA, AUX_SW_DATA, &reply_result_32); + *reply_result = (uint8_t)reply_result_32; - if (bytes_replied) { - uint32_t reply_result; + if (reply_result_32 >> 4 == 0) { /* ACK */ + uint32_t i = 0; - REG_UPDATE_1BY1_3(AUX_SW_DATA, - AUX_SW_INDEX, 0, - AUX_SW_AUTOINCREMENT_DISABLE, 1, - AUX_SW_DATA_RW, 1); + /* First byte was already used to get the command status */ + --bytes_replied; - REG_GET(AUX_SW_DATA, - AUX_SW_DATA, &reply_result); + /* Do not overflow buffer */ + if (bytes_replied > size) + return -1; - reply_result = reply_result >> 4; + while (i < bytes_replied) { + uint32_t aux_sw_data_val; - switch (reply_result) { - case 0: /* ACK */ { - uint32_t i = 0; + REG_GET(AUX_SW_DATA, AUX_SW_DATA, &aux_sw_data_val); + buffer[i] = aux_sw_data_val; + ++i; + } - /* first byte was already used - * to get the command status */ - --bytes_replied; + return i; + } + + return 0; +} + +static void process_channel_reply( + struct aux_engine *engine, + struct aux_reply_transaction_data *reply) +{ + int bytes_replied; + uint8_t reply_result; + uint32_t sw_status; - while (i < bytes_replied) { - uint32_t aux_sw_data_val; + bytes_replied = read_channel_reply(engine, reply->length, reply->data, + &reply_result, &sw_status); - REG_GET(AUX_SW_DATA, - AUX_SW_DATA, &aux_sw_data_val); + /* in case HPD is LOW, exit AUX transaction */ + if ((sw_status & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) { + reply->status = AUX_CHANNEL_OPERATION_FAILED_HPD_DISCON; + return; + } - reply->data[i] = aux_sw_data_val; - ++i; - } + if (bytes_replied < 0) { + /* Need to handle an error case... + * Hopefully, upper layer function won't call this function if + * the number of bytes in the reply was 0, because there was + * surely an error that was asserted that should have been + * handled for hot plug case, this could happens + */ + if (!(sw_status & AUX_SW_STATUS__AUX_SW_HPD_DISCON_MASK)) { + reply->status = AUX_TRANSACTION_REPLY_INVALID; + ASSERT_CRITICAL(false); + return; + } + } else { + reply_result = reply_result >> 4; + switch (reply_result) { + case 0: /* ACK */ reply->status = AUX_TRANSACTION_REPLY_AUX_ACK; - } break; case 1: /* NACK */ reply->status = AUX_TRANSACTION_REPLY_AUX_NACK; @@ -346,17 +377,6 @@ static void process_channel_reply( default: reply->status = AUX_TRANSACTION_REPLY_INVALID; } - } else { - /* Need to handle an error case... - * hopefully, upper layer function won't call this function - * if the number of bytes in the reply was 0 - * 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)) { - reply->status = AUX_TRANSACTION_REPLY_INVALID; - ASSERT_CRITICAL(false); - } } } @@ -427,6 +447,7 @@ static const struct aux_engine_funcs aux_engine_funcs = { .acquire_engine = acquire_engine, .submit_channel_request = submit_channel_request, .process_channel_reply = process_channel_reply, + .read_channel_reply = read_channel_reply, .get_channel_status = get_channel_status, .is_engine_available = is_engine_available, }; -- 2.7.4