[PATCH v5 02/11] drm/msm/dp: read hw revision only once

[Dmitry Baryshkov]

There is little point in rereading DP controller revision over and over
again. Read it once, after the first software reset.

Reviewed-by: Stephen Boyd <swboyd at chromium.org>
Tested-by: Stephen Boyd <swboyd at chromium.org> # sc7180-trogdor
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
 drivers/gpu/drm/msm/dp/dp_catalog.c | 29 ++++++++---------------------
 drivers/gpu/drm/msm/dp/dp_catalog.h |  2 +-
 2 files changed, 9 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
index 4f80eceb6ae19f542110d7379007f57c2ac16a8a..23f9fcb75123a58b3a4b69d3dad0598135108eec 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.c
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
@@ -414,14 +414,13 @@ void msm_dp_catalog_ctrl_config_misc(struct msm_dp_catalog *msm_dp_catalog,
 
 void msm_dp_catalog_setup_peripheral_flush(struct msm_dp_catalog *msm_dp_catalog)
 {
-	u32 mainlink_ctrl, hw_revision;
+	u32 mainlink_ctrl;
 	struct msm_dp_catalog_private *catalog = container_of(msm_dp_catalog,
 				struct msm_dp_catalog_private, msm_dp_catalog);
 
 	mainlink_ctrl = msm_dp_read_link(catalog, REG_DP_MAINLINK_CTRL);
 
-	hw_revision = msm_dp_catalog_hw_revision(msm_dp_catalog);
-	if (hw_revision >= DP_HW_VERSION_1_2)
+	if (msm_dp_catalog->hw_revision >= DP_HW_VERSION_1_2)
 		mainlink_ctrl |= DP_MAINLINK_FLUSH_MODE_SDE_PERIPH_UPDATE;
 	else
 		mainlink_ctrl |= DP_MAINLINK_FLUSH_MODE_UPDATE_SDP;
@@ -514,22 +513,6 @@ int msm_dp_catalog_ctrl_set_pattern_state_bit(struct msm_dp_catalog *msm_dp_cata
 	return 0;
 }
 
-/**
- * msm_dp_catalog_hw_revision() - retrieve DP hw revision
- *
- * @msm_dp_catalog: DP catalog structure
- *
- * Return: DP controller hw revision
- *
- */
-u32 msm_dp_catalog_hw_revision(const struct msm_dp_catalog *msm_dp_catalog)
-{
-	const struct msm_dp_catalog_private *catalog = container_of(msm_dp_catalog,
-				struct msm_dp_catalog_private, msm_dp_catalog);
-
-	return msm_dp_read_ahb(catalog, REG_DP_HW_VERSION);
-}
-
 /**
  * msm_dp_catalog_ctrl_reset() - reset DP controller
  *
@@ -556,6 +539,9 @@ void msm_dp_catalog_ctrl_reset(struct msm_dp_catalog *msm_dp_catalog)
 
 	sw_reset &= ~DP_SW_RESET;
 	msm_dp_write_ahb(catalog, REG_DP_SW_RESET, sw_reset);
+
+	if (!msm_dp_catalog->hw_revision)
+		msm_dp_catalog->hw_revision = msm_dp_read_ahb(catalog, REG_DP_HW_VERSION);
 }
 
 bool msm_dp_catalog_ctrl_mainlink_ready(struct msm_dp_catalog *msm_dp_catalog)
@@ -895,9 +881,10 @@ static void msm_dp_catalog_panel_update_sdp(struct msm_dp_catalog *msm_dp_catalo
 	u32 hw_revision;
 
 	catalog = container_of(msm_dp_catalog, struct msm_dp_catalog_private, msm_dp_catalog);
+	hw_revision = msm_dp_catalog->hw_revision;
 
-	hw_revision = msm_dp_catalog_hw_revision(msm_dp_catalog);
-	if (hw_revision < DP_HW_VERSION_1_2 && hw_revision >= DP_HW_VERSION_1_0) {
+	if (hw_revision < DP_HW_VERSION_1_2 &&
+	    hw_revision >= DP_HW_VERSION_1_0) {
 		msm_dp_write_link(catalog, MMSS_DP_SDP_CFG3, 0x01);
 		msm_dp_write_link(catalog, MMSS_DP_SDP_CFG3, 0x00);
 	}
diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h b/drivers/gpu/drm/msm/dp/dp_catalog.h
index 08bb42e91b779633875dbeb4130bc55a6571cfb1..379fa4fef9ceb63b20c4aec2fca1e09003dc738b 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.h
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
@@ -33,6 +33,7 @@
 
 struct msm_dp_catalog {
 	bool wide_bus_en;
+	u32 hw_revision;
 };
 
 /* Debug module */
@@ -61,7 +62,6 @@ void msm_dp_catalog_ctrl_config_misc(struct msm_dp_catalog *msm_dp_catalog, u32
 void msm_dp_catalog_ctrl_config_msa(struct msm_dp_catalog *msm_dp_catalog, u32 rate,
 				u32 stream_rate_khz, bool is_ycbcr_420);
 int msm_dp_catalog_ctrl_set_pattern_state_bit(struct msm_dp_catalog *msm_dp_catalog, u32 pattern);
-u32 msm_dp_catalog_hw_revision(const struct msm_dp_catalog *msm_dp_catalog);
 void msm_dp_catalog_ctrl_reset(struct msm_dp_catalog *msm_dp_catalog);
 bool msm_dp_catalog_ctrl_mainlink_ready(struct msm_dp_catalog *msm_dp_catalog);
 void msm_dp_catalog_ctrl_enable_irq(struct msm_dp_catalog *msm_dp_catalog, bool enable);

-- 
2.39.5