From: Roy Chan <roy.chan@xxxxxxx>
[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.
Reviewed-by: Aric Cyr <Aric.Cyr@xxxxxxx>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Signed-off-by: Roy Chan <roy.chan@xxxxxxx>
---
drivers/gpu/drm/amd/display/dc/dc_helper.c | 60 +++++++++++++++++++
.../gpu/drm/amd/display/dc/inc/reg_helper.h | 34 +++++++++++
2 files changed, 94 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dc_helper.c b/drivers/gpu/drm/amd/display/dc/dc_helper.c
index a612ba6dc389..05ad9f52b9c7 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
diff --git a/drivers/gpu/drm/amd/display/dc/inc/reg_helper.h b/drivers/gpu/drm/amd/display/dc/inc/reg_helper.h
index 2470405e996b..a402df225a76 100644
--- a/drivers/gpu/drm/amd/display/dc/inc/reg_helper.h
+++ b/drivers/gpu/drm/amd/display/dc/inc/reg_helper.h
@@ -498,6 +498,40 @@ uint32_t generic_indirect_reg_update_ex(const struct dc_context *ctx,
uint8_t shift1, uint32_t mask1, uint32_t field_value1,
...);
+/* indirect register access
+ * underlying implementation determines which index/data pair to be used
+ * in a synchronous way
+ */
+#define IX_REG_SET_N_SYNC(index, n, initial_val, ...) \
+ generic_indirect_reg_update_ex_sync(CTX, \
+ IND_REG(index), \
+ initial_val, \
+ n, __VA_ARGS__)
+
+#define IX_REG_SET_2_SYNC(index, init_value, f1, v1, f2, v2) \
+ IX_REG_SET_N_SYNC(index, 2, init_value, \
+ FN(reg, f1), v1,\
+ FN(reg, f2), v2)
+
+#define IX_REG_GET_N_SYNC(index, n, ...) \
+ generic_indirect_reg_get_sync(CTX, \
+ IND_REG(index), \
+ n, __VA_ARGS__)
+
+#define IX_REG_GET_SYNC(index, field, val) \
+ IX_REG_GET_N_SYNC(index, 1, \
+ FN(data_reg_name, field), 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 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,
+ ...);
+
/* register offload macros
*
* instead of MMIO to register directly, in some cases we want
--
2.25.1
