drm/amd/display: Support synchronized indirect reg access

[Why]
indirect register index/data pair may be used by multi-threads.  when it
happens, it would cause register access issue that is hard to trace.

[How]
Using cgs service, which provide a sync indirect reg access api.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Roy Chan <roy.chan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 60 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dc_helper.c b/drivers/gpu/drm/amd/display/dc/dc_helper.c
index ab6bc5d79012..f43cce16bb6c 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_helper.c
+++ b/drivers/gpu/drm/amd/display/dc/dc_helper.c
@@ -588,6 +588,66 @@ uint32_t generic_indirect_reg_update_ex(const struct dc_context *ctx,
 	return reg_val;
 }
 
+
+uint32_t generic_indirect_reg_update_ex_sync(const struct dc_context *ctx,
+		uint32_t index, uint32_t reg_val, int n,
+		uint8_t shift1, uint32_t mask1, uint32_t field_value1,
+		...)
+{
+	uint32_t shift, mask, field_value;
+	int i = 1;
+
+	va_list ap;
+
+	va_start(ap, field_value1);
+
+	reg_val = set_reg_field_value_ex(reg_val, field_value1, mask1, shift1);
+
+	while (i < n) {
+		shift = va_arg(ap, uint32_t);
+		mask = va_arg(ap, uint32_t);
+		field_value = va_arg(ap, uint32_t);
+
+		reg_val = set_reg_field_value_ex(reg_val, field_value, mask, shift);
+		i++;
+	}
+
+	dm_write_index_reg(ctx, CGS_IND_REG__PCIE, index, reg_val);
+	va_end(ap);
+
+	return reg_val;
+}
+
+uint32_t generic_indirect_reg_get_sync(const struct dc_context *ctx,
+		uint32_t index, int n,
+		uint8_t shift1, uint32_t mask1, uint32_t *field_value1,
+		...)
+{
+	uint32_t shift, mask, *field_value;
+	uint32_t value = 0;
+	int i = 1;
+
+	va_list ap;
+
+	va_start(ap, field_value1);
+
+	value = dm_read_index_reg(ctx, CGS_IND_REG__PCIE, index);
+	*field_value1 = get_reg_field_value_ex(value, mask1, shift1);
+
+	while (i < n) {
+		shift = va_arg(ap, uint32_t);
+		mask = va_arg(ap, uint32_t);
+		field_value = va_arg(ap, uint32_t *);
+
+		*field_value = get_reg_field_value_ex(value, mask, shift);
+		i++;
+	}
+
+	va_end(ap);
+
+	return value;
+}
+
 void reg_sequence_start_gather(const struct dc_context *ctx)
 {
 	/* if reg sequence is supported and enabled, set flag to