OMAPDSS: DISPC: Correct DISPC functional clock usage

DISPC_FCLK is incorrectly used as functional clock of DISPC in scaling
calculations. So, DISPC_CORE_CLK replaces as functional clock of DISPC.
DISPC_CORE_CLK is derived from DISPC_FCLK divided by an independent DISPC
divisor LCD.

Signed-off-by: Chandrabhanu Mahapatra <cmahapatra@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

2 files changed, 41 insertions, 27 deletions

diff --git a/drivers/video/omap2/dss/dispc.c b/drivers/video/omap2/dss/dispc.c
index bea37bbd0e3e..49015b8a9e4a 100644
--- a/drivers/video/omap2/dss/dispc.c
+++ b/drivers/video/omap2/dss/dispc.c
@@ -1714,11 +1714,11 @@ static int check_horiz_timing_omap3(enum omap_channel channel, u16 pos_x,
         return 0;
 }
 
-static unsigned long calc_fclk_five_taps(enum omap_channel channel, u16 width,
-                u16 height, u16 out_width, u16 out_height,
+static unsigned long calc_core_clk_five_taps(enum omap_channel channel,
+                u16 width, u16 height, u16 out_width, u16 out_height,
                 enum omap_color_mode color_mode)
 {
-        u32 fclk = 0;
+        u32 core_clk = 0;
         u64 tmp, pclk = dispc_mgr_pclk_rate(channel);
 
         if (height <= out_height && width <= out_width)
@@ -1730,7 +1730,7 @@ static unsigned long calc_fclk_five_taps(enum omap_channel channel, u16 width,
 
                 tmp = pclk * height * out_width;
                 do_div(tmp, 2 * out_height * ppl);
-                fclk = tmp;
+                core_clk = tmp;
 
                 if (height > 2 * out_height) {
                         if (ppl == out_width)
@@ -1738,23 +1738,23 @@ static unsigned long calc_fclk_five_taps(enum omap_channel channel, u16 width,
 
                         tmp = pclk * (height - 2 * out_height) * out_width;
                         do_div(tmp, 2 * out_height * (ppl - out_width));
-                        fclk = max(fclk, (u32) tmp);
+                        core_clk = max_t(u32, core_clk, tmp);
                 }
         }
 
         if (width > out_width) {
                 tmp = pclk * width;
                 do_div(tmp, out_width);
-                fclk = max(fclk, (u32) tmp);
+                core_clk = max_t(u32, core_clk, tmp);
 
                 if (color_mode == OMAP_DSS_COLOR_RGB24U)
-                        fclk <<= 1;
+                        core_clk <<= 1;
         }
 
-        return fclk;
+        return core_clk;
 }
 
-static unsigned long calc_fclk(enum omap_channel channel, u16 width,
+static unsigned long calc_core_clk(enum omap_channel channel, u16 width,
                 u16 height, u16 out_width, u16 out_height)
 {
         unsigned int hf, vf;
@@ -1805,7 +1805,7 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
         const int maxsinglelinewidth =
                                 dss_feat_get_param_max(FEAT_PARAM_LINEWIDTH);
         const int max_decim_limit = 16;
-        unsigned long fclk = 0;
+        unsigned long core_clk = 0;
         int decim_x, decim_y, error, min_factor;
         u16 in_width, in_height, in_width_max = 0;
 
@@ -1845,10 +1845,10 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
                 do {
                         in_height = DIV_ROUND_UP(height, decim_y);
                         in_width = DIV_ROUND_UP(width, decim_x);
-                        fclk = calc_fclk(channel, in_width, in_height,
+                        core_clk = calc_core_clk(channel, in_width, in_height,
                                         out_width, out_height);
-                        error = (in_width > maxsinglelinewidth || !fclk ||
-                                fclk > dispc_fclk_rate());
+                        error = (in_width > maxsinglelinewidth || !core_clk ||
+                                core_clk > dispc_core_clk_rate());
                         if (error) {
                                 if (decim_x == decim_y) {
                                         decim_x = min_factor;
@@ -1871,8 +1871,8 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
                 do {
                         in_height = DIV_ROUND_UP(height, decim_y);
                         in_width = DIV_ROUND_UP(width, decim_x);
-                        fclk = calc_fclk_five_taps(channel, in_width, in_height,
-                                out_width, out_height, color_mode);
+                        core_clk = calc_core_clk_five_taps(channel, in_width,
+                                in_height, out_width, out_height, color_mode);
 
                         error = check_horiz_timing_omap3(channel, pos_x,
                                 in_width, in_height, out_width, out_height);
@@ -1882,11 +1882,11 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
                                         in_height < out_height * 2)
                                         *five_taps = false;
                         if (!*five_taps)
-                                fclk = calc_fclk(channel, in_width, in_height,
-                                        out_width, out_height);
+                                core_clk = calc_core_clk(channel, in_width,
+                                        in_height, out_width, out_height);
                         error = (error || in_width > maxsinglelinewidth * 2 ||
                                 (in_width > maxsinglelinewidth && *five_taps) ||
-                                !fclk || fclk > dispc_fclk_rate());
+                                !core_clk || core_clk > dispc_core_clk_rate());
                         if (error) {
                                 if (decim_x == decim_y) {
                                         decim_x = min_factor;
@@ -1919,7 +1919,7 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
         } else {
                 int decim_x_min = decim_x;
                 in_height = DIV_ROUND_UP(height, decim_y);
-                in_width_max = dispc_fclk_rate() /
+                in_width_max = dispc_core_clk_rate() /
                                 DIV_ROUND_UP(dispc_mgr_pclk_rate(channel),
                                                 out_width);
                 decim_x = DIV_ROUND_UP(width, in_width_max);
@@ -1938,18 +1938,18 @@ static int dispc_ovl_calc_scaling(enum omap_plane plane,
                         return -EINVAL;
                 }
 
-                fclk = calc_fclk(channel, in_width, in_height, out_width,
-                                out_height);
+                core_clk = calc_core_clk(channel, in_width, in_height,
+                                out_width, out_height);
         }
 
-        DSSDBG("required fclk rate = %lu Hz\n", fclk);
-        DSSDBG("current fclk rate = %lu Hz\n", dispc_fclk_rate());
+        DSSDBG("required core clk rate = %lu Hz\n", core_clk);
+        DSSDBG("current core clk rate = %lu Hz\n", dispc_core_clk_rate());
 
-        if (!fclk || fclk > dispc_fclk_rate()) {
+        if (!core_clk || core_clk > dispc_core_clk_rate()) {
                 DSSERR("failed to set up scaling, "
-                        "required fclk rate = %lu Hz, "
-                        "current fclk rate = %lu Hz\n",
-                        fclk, dispc_fclk_rate());
+                        "required core clk rate = %lu Hz, "
+                        "current core clk rate = %lu Hz\n",
+                        core_clk, dispc_core_clk_rate());
                 return -EINVAL;
         }
 
@@ -2657,6 +2657,19 @@ unsigned long dispc_mgr_pclk_rate(enum omap_channel channel)
         }
 }
 
+unsigned long dispc_core_clk_rate(void)
+{
+        int lcd;
+        unsigned long fclk = dispc_fclk_rate();
+
+        if (dss_has_feature(FEAT_CORE_CLK_DIV))
+                lcd = REG_GET(DISPC_DIVISOR, 23, 16);
+        else
+                lcd = REG_GET(DISPC_DIVISORo(OMAP_DSS_CHANNEL_LCD), 23, 16);
+
+        return fclk / lcd;
+}
+
 void dispc_dump_clocks(struct seq_file *s)
 {
         int lcd, pcd;
diff --git a/drivers/video/omap2/dss/dss.h b/drivers/video/omap2/dss/dss.h
index 1dc336b8bb69..5ca67f111d09 100644
--- a/drivers/video/omap2/dss/dss.h
+++ b/drivers/video/omap2/dss/dss.h
@@ -448,6 +448,7 @@ void dispc_mgr_set_pol_freq(enum omap_channel channel,
                 enum omap_panel_config config, u8 acbi, u8 acb);
 unsigned long dispc_mgr_lclk_rate(enum omap_channel channel);
 unsigned long dispc_mgr_pclk_rate(enum omap_channel channel);
+unsigned long dispc_core_clk_rate(void);
 int dispc_mgr_set_clock_div(enum omap_channel channel,
                 struct dispc_clock_info *cinfo);
 int dispc_mgr_get_clock_div(enum omap_channel channel,