drm/amd/display: add SW_USE_I2C_REG request.

[Description]
This is for DC_I2c arbitration use between HW use/SW use and DMCU use.
Signed-off-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.c

@@ -268,6 +268,8 @@ static bool setup_engine(
 	struct dce_i2c_hw *dce_i2c_hw)
 {
 	uint32_t i2c_setup_limit = I2C_SETUP_TIME_LIMIT_DCE;
+	/* we have checked I2c not used by DMCU, set SW use I2C REQ to 1 to indicate SW using it*/
+	REG_UPDATE(DC_I2C_ARBITRATION, DC_I2C_SW_USE_I2C_REG_REQ, 1);
 
 	if (dce_i2c_hw->setup_limit != 0)
 		i2c_setup_limit = dce_i2c_hw->setup_limit;
@@ -322,8 +324,6 @@ static void release_engine(
 
 	set_speed(dce_i2c_hw, dce_i2c_hw->original_speed);
 
-	/* Release I2C */
-	REG_UPDATE(DC_I2C_ARBITRATION, DC_I2C_SW_DONE_USING_I2C_REG, 1);
 
 	/* Reset HW engine */
 	{
@@ -343,6 +343,9 @@ static void release_engine(
 	/* HW I2c engine - clock gating feature */
 	if (!dce_i2c_hw->engine_keep_power_up_count)
 		REG_UPDATE_N(SETUP, 1, FN(SETUP, DC_I2C_DDC1_ENABLE), 0);
+	/* Release I2C after reset, so HW or DMCU could use it */
+	REG_UPDATE_2(DC_I2C_ARBITRATION, DC_I2C_SW_DONE_USING_I2C_REG, 1,
+		DC_I2C_SW_USE_I2C_REG_REQ, 0);
 
 }
 

drivers/gpu/drm/amd/display/dc/dce/dce_i2c_hw.h

@@ -105,6 +105,7 @@ enum {
 	I2C_SF(DC_I2C_DDC1_SETUP, DC_I2C_DDC1_DATA_DRIVE_SEL, mask_sh),\
 	I2C_SF(DC_I2C_DDC1_SETUP, DC_I2C_DDC1_INTRA_TRANSACTION_DELAY, mask_sh),\
 	I2C_SF(DC_I2C_DDC1_SETUP, DC_I2C_DDC1_INTRA_BYTE_DELAY, mask_sh),\
+	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_SW_USE_I2C_REG_REQ, mask_sh),\
 	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_SW_DONE_USING_I2C_REG, mask_sh),\
 	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_NO_QUEUED_SW_GO, mask_sh),\
 	I2C_SF(DC_I2C_ARBITRATION, DC_I2C_SW_PRIORITY, mask_sh),\
@@ -146,6 +147,7 @@ struct dce_i2c_shift {
 	uint8_t DC_I2C_DDC1_INTRA_TRANSACTION_DELAY;
 	uint8_t DC_I2C_DDC1_INTRA_BYTE_DELAY;
 	uint8_t DC_I2C_SW_DONE_USING_I2C_REG;
+	uint8_t DC_I2C_SW_USE_I2C_REG_REQ;
 	uint8_t DC_I2C_NO_QUEUED_SW_GO;
 	uint8_t DC_I2C_SW_PRIORITY;
 	uint8_t DC_I2C_SOFT_RESET;
@@ -184,6 +186,7 @@ struct dce_i2c_mask {
 	uint32_t DC_I2C_DDC1_INTRA_TRANSACTION_DELAY;
 	uint32_t DC_I2C_DDC1_INTRA_BYTE_DELAY;
 	uint32_t DC_I2C_SW_DONE_USING_I2C_REG;
+	uint32_t DC_I2C_SW_USE_I2C_REG_REQ;
 	uint32_t DC_I2C_NO_QUEUED_SW_GO;
 	uint32_t DC_I2C_SW_PRIORITY;
 	uint32_t DC_I2C_SOFT_RESET;