drm/amd/display: Add GPINT handler interface

[Why]
The General Purpose Interrupt is used on the DMCUB to pass lightweight
commands via a register to the DMCUB.

This is limited to 32-bit command and 32-bit response.

This will be used for shutting down the firmware in a clean manner.

[How]
Add the command IDs and the data register to correctly format
the commands.

Add the interface functions to dmub_srv for sending and receiving the
commands.

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@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>

3 files changed, 81 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c
index b2ca8e0dbac9..7c1604c2221c 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c
@@ -217,3 +217,25 @@ bool dmub_dcn20_is_supported(struct dmub_srv *dmub)
 
 	return supported;
 }
+
+void dmub_dcn20_set_gpint(struct dmub_srv *dmub,
+			  union dmub_gpint_data_register reg)
+{
+	REG_WRITE(DMCUB_GPINT_DATAIN1, reg.all);
+}
+
+bool dmub_dcn20_is_gpint_acked(struct dmub_srv *dmub,
+			       union dmub_gpint_data_register reg)
+{
+	union dmub_gpint_data_register test;
+
+	reg.bits.status = 0;
+	test.all = REG_READ(DMCUB_GPINT_DATAIN1);
+
+	return test.all == reg.all;
+}
+
+uint32_t dmub_dcn20_get_gpint_response(struct dmub_srv *dmub)
+{
+	return REG_READ(DMCUB_SCRATCH7);
+}
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.h b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.h
index 04b0fa13153d..7f046c73927e 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.h
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.h
@@ -91,6 +91,7 @@ struct dmub_srv;
 	DMUB_SR(DMCUB_SCRATCH13) \
 	DMUB_SR(DMCUB_SCRATCH14) \
 	DMUB_SR(DMCUB_SCRATCH15) \
+	DMUB_SR(DMCUB_GPINT_DATAIN1) \
 	DMUB_SR(CC_DC_PIPE_DIS) \
 	DMUB_SR(MMHUBBUB_SOFT_RESET) \
 	DMUB_SR(DCN_VM_FB_LOCATION_BASE) \
@@ -183,4 +184,12 @@ bool dmub_dcn20_is_hw_init(struct dmub_srv *dmub);
 
 bool dmub_dcn20_is_supported(struct dmub_srv *dmub);
 
+void dmub_dcn20_set_gpint(struct dmub_srv *dmub,
+			  union dmub_gpint_data_register reg);
+
+bool dmub_dcn20_is_gpint_acked(struct dmub_srv *dmub,
+			       union dmub_gpint_data_register reg);
+
+uint32_t dmub_dcn20_get_gpint_response(struct dmub_srv *dmub);
+
 #endif /* _DMUB_DCN20_H_ */
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
index 85a518bf8a76..45be185ef312 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
@@ -126,6 +126,9 @@ static bool dmub_srv_hw_setup(struct dmub_srv *dmub, enum dmub_asic asic)
 		funcs->set_inbox1_wptr = dmub_dcn20_set_inbox1_wptr;
 		funcs->is_supported = dmub_dcn20_is_supported;
 		funcs->is_hw_init = dmub_dcn20_is_hw_init;
+		funcs->set_gpint = dmub_dcn20_set_gpint;
+		funcs->is_gpint_acked = dmub_dcn20_is_gpint_acked;
+		funcs->get_gpint_response = dmub_dcn20_get_gpint_response;
 
 		if (asic == DMUB_ASIC_DCN21) {
 			dmub->regs = &dmub_srv_dcn21_regs;
@@ -522,3 +525,50 @@ enum dmub_status dmub_srv_wait_for_idle(struct dmub_srv *dmub,
 
 	return DMUB_STATUS_TIMEOUT;
 }
+
+enum dmub_status
+dmub_srv_send_gpint_command(struct dmub_srv *dmub,
+			    enum dmub_gpint_command command_code,
+			    uint16_t param, uint32_t timeout_us)
+{
+	union dmub_gpint_data_register reg;
+	uint32_t i;
+
+	if (!dmub->sw_init)
+		return DMUB_STATUS_INVALID;
+
+	if (!dmub->hw_funcs.set_gpint)
+		return DMUB_STATUS_INVALID;
+
+	if (!dmub->hw_funcs.is_gpint_acked)
+		return DMUB_STATUS_INVALID;
+
+	reg.bits.status = 1;
+	reg.bits.command_code = command_code;
+	reg.bits.param = param;
+
+	dmub->hw_funcs.set_gpint(dmub, reg);
+
+	for (i = 0; i < timeout_us; ++i) {
+		if (dmub->hw_funcs.is_gpint_acked(dmub, reg))
+			return DMUB_STATUS_OK;
+	}
+
+	return DMUB_STATUS_TIMEOUT;
+}
+
+enum dmub_status dmub_srv_get_gpint_response(struct dmub_srv *dmub,
+					     uint32_t *response)
+{
+	*response = 0;
+
+	if (!dmub->sw_init)
+		return DMUB_STATUS_INVALID;
+
+	if (!dmub->hw_funcs.get_gpint_response)
+		return DMUB_STATUS_INVALID;
+
+	*response = dmub->hw_funcs.get_gpint_response(dmub);
+
+	return DMUB_STATUS_OK;
+}