soc: qcom: ubwc: add helper to get min_acc length

MDSS and GPU drivers use different approaches to get min_acc length.
Add helper function that can be used by all the drivers.

The helper reflects our current best guess, it blindly copies the
approach adopted by the MDSS drivers and it matches current values
selected by the GPU driver.

Reviewed-by: Bryan O'Donoghue <[email protected]>
Acked-by: Bjorn Andersson <[email protected]>
Reviewed-by: Konrad Dybcio <[email protected]>
Reviewed-by: Dikshita Agarwal <[email protected]>
Tested-by: Wangao Wang <[email protected]>
Signed-off-by: Dmitry Baryshkov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bjorn Andersson <[email protected]>

Author: lumag

include/linux/soc/qcom/ubwc.h

@@ -74,4 +74,14 @@ static inline bool qcom_ubwc_get_ubwc_mode(const struct qcom_ubwc_cfg_data *cfg)
 	return ret;
 }
 
+/*
+ * This is the best guess, based on the MDSS driver, which worked so far.
+ */
+static inline bool qcom_ubwc_min_acc_length_64b(const struct qcom_ubwc_cfg_data *cfg)
+{
+	return cfg->ubwc_enc_version == UBWC_1_0 &&
+		(cfg->ubwc_dec_version == UBWC_2_0 ||
+		 cfg->ubwc_dec_version == UBWC_3_0);
+}
+
 #endif /* __QCOM_UBWC_H__ */