diff mbox series

[v2,076/106] ccs-pll: Add support flexible OP PLL pixel clock divider

Message ID 20201007084557.25843-67-sakari.ailus@linux.intel.com
State Accepted
Commit 9490a2279fab29cf8730120b54c42ef2fc67171c
Headers show
Series None | expand

Commit Message

Sakari Ailus Oct. 7, 2020, 8:45 a.m. UTC 
Flexible OP PLL pixel clock divider allows a higher OP pixel clock than
what the bus can transfer. This generally makes it easier to select pixel
clock dividers.

This changes how the pixel rate on the bus and minimum VT divisor are
calculated, as the pixel rate is no longer directly determined by the
OP pixel clock and the number of the lanes.

Also add a sanity check for sensors that do not support flexible OP PLL
pixel clock divider. This could have caused the PLL calculator to come up
with an invalid configuration for those devices.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/i2c/ccs-pll.c      | 26 +++++++++++++++++++-------
 drivers/media/i2c/ccs-pll.h      |  1 +
 drivers/media/i2c/ccs/ccs-core.c |  4 +++-
 3 files changed, 23 insertions(+), 8 deletions(-)
diff mbox series

Patch

diff --git a/drivers/media/i2c/ccs-pll.c b/drivers/media/i2c/ccs-pll.c
index 60ab0c043c7a..e3a6493fd601 100644
--- a/drivers/media/i2c/ccs-pll.c
+++ b/drivers/media/i2c/ccs-pll.c
@@ -294,11 +294,11 @@  __ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim,
 	 * Find absolute limits for the factor of vt divider.
 	 */
 	dev_dbg(dev, "scale_m: %u\n", pll->scale_m);
-	min_vt_div = DIV_ROUND_UP(op_pll_bk->pix_clk_div
-				  * op_pll_bk->sys_clk_div * pll->scale_n
-				  * pll->vt_lanes * l,
-				  pll->op_lanes * vt_op_binning_div
-				  * pll->scale_m);
+	min_vt_div = DIV_ROUND_UP(pll->bits_per_pixel * op_pll_bk->sys_clk_div
+				  * pll->scale_n * pll->vt_lanes,
+				  (pll->flags & CCS_PLL_FLAG_LANE_SPEED_MODEL ?
+				   pll->csi2.lanes : 1)
+				  * vt_op_binning_div * pll->scale_m);
 
 	/* Find smallest and biggest allowed vt divisor. */
 	dev_dbg(dev, "min_vt_div: %u\n", min_vt_div);
@@ -420,6 +420,18 @@  int ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim,
 		pll->op_lanes = 1;
 		pll->vt_lanes = 1;
 	}
+
+	/*
+	 * Make sure op_pix_clk_div will be integer --- unless flexible
+	 * op_pix_clk_div is supported
+	 */
+	if (!(pll->flags & CCS_PLL_FLAG_FLEXIBLE_OP_PIX_CLK_DIV) &&
+	    (pll->bits_per_pixel * pll->op_lanes) % (pll->csi2.lanes * l)) {
+		dev_dbg(dev, "op_pix_clk_div not an integer (bpp %u, op lanes %u, lanes %u, l %u)\n",
+			pll->bits_per_pixel, pll->op_lanes, pll->csi2.lanes, l);
+		return -EINVAL;
+	}
+
 	dev_dbg(dev, "vt_lanes: %u\n", pll->vt_lanes);
 	dev_dbg(dev, "op_lanes: %u\n", pll->op_lanes);
 
@@ -449,9 +461,9 @@  int ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim,
 	}
 
 	pll->pixel_rate_csi =
-		op_pll_bk->pix_clk_freq_hz
+		op_pll_bk->sys_clk_freq_hz
 		* (pll->flags & CCS_PLL_FLAG_LANE_SPEED_MODEL ?
-		   pll->csi2.lanes : 1) / l;
+		   pll->csi2.lanes : 1) / pll->bits_per_pixel / l;
 
 	/* Figure out limits for OP pre-pll divider based on extclk */
 	dev_dbg(dev, "min / max op_pre_pll_clk_div: %u / %u\n",
diff --git a/drivers/media/i2c/ccs-pll.h b/drivers/media/i2c/ccs-pll.h
index dd97cd6dca0d..0c25c5f5d4e4 100644
--- a/drivers/media/i2c/ccs-pll.h
+++ b/drivers/media/i2c/ccs-pll.h
@@ -26,6 +26,7 @@ 
 #define CCS_PLL_FLAG_LANE_SPEED_MODEL				BIT(2)
 #define CCS_PLL_FLAG_LINK_DECOUPLED				BIT(3)
 #define CCS_PLL_FLAG_EXT_IP_PLL_DIVIDER				BIT(4)
+#define CCS_PLL_FLAG_FLEXIBLE_OP_PIX_CLK_DIV			BIT(5)
 
 /**
  * struct ccs_pll_branch_fr - CCS PLL configuration (front)
diff --git a/drivers/media/i2c/ccs/ccs-core.c b/drivers/media/i2c/ccs/ccs-core.c
index 8f8bda98b0b7..ab6abcf4c1dd 100644
--- a/drivers/media/i2c/ccs/ccs-core.c
+++ b/drivers/media/i2c/ccs/ccs-core.c
@@ -30,7 +30,6 @@ 
 #include <media/v4l2-device.h>
 
 #include "ccs.h"
-#include "ccs-limits.h"
 
 #define CCS_ALIGN_DIM(dim, flags)	\
 	((flags) & V4L2_SEL_FLAG_GE	\
@@ -3214,6 +3213,9 @@  static int ccs_probe(struct i2c_client *client)
 	if (CCS_LIM(sensor, CLOCK_TREE_PLL_CAPABILITY) &
 	    CCS_CLOCK_TREE_PLL_CAPABILITY_EXT_DIVIDER)
 		sensor->pll.flags |= CCS_PLL_FLAG_EXT_IP_PLL_DIVIDER;
+	if (CCS_LIM(sensor, CLOCK_TREE_PLL_CAPABILITY) &
+	    CCS_CLOCK_TREE_PLL_CAPABILITY_FLEXIBLE_OP_PIX_CLK_DIV)
+		sensor->pll.flags |= CCS_PLL_FLAG_FLEXIBLE_OP_PIX_CLK_DIV;
 	sensor->pll.op_bits_per_lane = CCS_LIM(sensor, OP_BITS_PER_LANE);
 	sensor->pll.ext_clk_freq_hz = sensor->hwcfg.ext_clk;
 	sensor->pll.scale_n = CCS_LIM(sensor, SCALER_N_MIN);