OMAPDSS: DSI: remove option to use pck for DSI PLL clkin

For some OMAP versions the TRM says that the pixel clock from DISPC can
be used as an input clock for DSI PLL, instead of the default, which is
sysclk.  For some OMAP versions the bits affecting this are marked as
reserved.  This feature has never been tested, so it's unknown if the HW
even works, and has never been used.

To clean things up, this patch removes the functionality. This should
not affect any board.

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

drivers/video/omap2/dss/dsi.c

@@ -1279,10 +1279,9 @@ static int dsi_pll_power(struct platform_device *dsidev,
 }
 
 /* calculate clock rates using dividers in cinfo */
-static int dsi_calc_clock_rates(struct omap_dss_device *dssdev,
+static int dsi_calc_clock_rates(struct platform_device *dsidev,
 		struct dsi_clock_info *cinfo)
 {
-	struct platform_device *dsidev = dsi_get_dsidev_from_dssdev(dssdev);
 	struct dsi_data *dsi = dsi_get_dsidrv_data(dsidev);
 
 	if (cinfo->regn == 0 || cinfo->regn > dsi->regn_max)
@@ -1297,21 +1296,8 @@ static int dsi_calc_clock_rates(struct omap_dss_device *dssdev,
 	if (cinfo->regm_dsi > dsi->regm_dsi_max)
 		return -EINVAL;
 
-	if (cinfo->use_sys_clk) {
-		cinfo->clkin = clk_get_rate(dsi->sys_clk);
-		/* XXX it is unclear if highfreq should be used
-		 * with DSS_SYS_CLK source also */
-		cinfo->highfreq = 0;
-	} else {
-		cinfo->clkin = dispc_mgr_pclk_rate(dssdev->manager->id);
-
-		if (cinfo->clkin < 32000000)
-			cinfo->highfreq = 0;
-		else
-			cinfo->highfreq = 1;
-	}
-
-	cinfo->fint = cinfo->clkin / (cinfo->regn * (cinfo->highfreq ? 2 : 1));
+	cinfo->clkin = clk_get_rate(dsi->sys_clk);
+	cinfo->fint = cinfo->clkin / cinfo->regn;
 
 	if (cinfo->fint > dsi->fint_max || cinfo->fint < dsi->fint_min)
 		return -EINVAL;
@@ -1378,27 +1364,21 @@ retry:
 
 	memset(&cur, 0, sizeof(cur));
 	cur.clkin = dss_sys_clk;
-	cur.use_sys_clk = 1;
-	cur.highfreq = 0;
 
-	/* no highfreq: 0.75MHz < Fint = clkin / regn < 2.1MHz */
-	/* highfreq: 0.75MHz < Fint = clkin / (2*regn) < 2.1MHz */
+	/* 0.75MHz < Fint = clkin / regn < 2.1MHz */
 	/* To reduce PLL lock time, keep Fint high (around 2 MHz) */
 	for (cur.regn = 1; cur.regn < dsi->regn_max; ++cur.regn) {
-		if (cur.highfreq == 0)
-			cur.fint = cur.clkin / cur.regn;
-		else
-			cur.fint = cur.clkin / (2 * cur.regn);
+		cur.fint = cur.clkin / cur.regn;
 
 		if (cur.fint > dsi->fint_max || cur.fint < dsi->fint_min)
 			continue;
 
-		/* DSIPHY(MHz) = (2 * regm / regn) * (clkin / (highfreq + 1)) */
+		/* DSIPHY(MHz) = (2 * regm / regn) * clkin */
 		for (cur.regm = 1; cur.regm < dsi->regm_max; ++cur.regm) {
 			unsigned long a, b;
 
 			a = 2 * cur.regm * (cur.clkin/1000);
-			b = cur.regn * (cur.highfreq + 1);
+			b = cur.regn;
 			cur.clkin4ddr = a / b * 1000;
 
 			if (cur.clkin4ddr > 1800 * 1000 * 1000)
@@ -1486,9 +1466,7 @@ int dsi_pll_set_clock_div(struct platform_device *dsidev,
 
 	DSSDBGF();
 
-	dsi->current_cinfo.use_sys_clk = cinfo->use_sys_clk;
-	dsi->current_cinfo.highfreq = cinfo->highfreq;
-
+	dsi->current_cinfo.clkin = cinfo->clkin;
 	dsi->current_cinfo.fint = cinfo->fint;
 	dsi->current_cinfo.clkin4ddr = cinfo->clkin4ddr;
 	dsi->current_cinfo.dsi_pll_hsdiv_dispc_clk =
@@ -1503,17 +1481,13 @@ int dsi_pll_set_clock_div(struct platform_device *dsidev,
 
 	DSSDBG("DSI Fint %ld\n", cinfo->fint);
 
-	DSSDBG("clkin (%s) rate %ld, highfreq %d\n",
-			cinfo->use_sys_clk ? "dss_sys_clk" : "pclkfree",
-			cinfo->clkin,
-			cinfo->highfreq);
+	DSSDBG("clkin rate %ld\n", cinfo->clkin);
 
 	/* DSIPHY == CLKIN4DDR */
-	DSSDBG("CLKIN4DDR = 2 * %d / %d * %lu / %d = %lu\n",
+	DSSDBG("CLKIN4DDR = 2 * %d / %d * %lu = %lu\n",
 			cinfo->regm,
 			cinfo->regn,
 			cinfo->clkin,
-			cinfo->highfreq + 1,
 			cinfo->clkin4ddr);
 
 	DSSDBG("Data rate on 1 DSI lane %ld Mbps\n",
@@ -1568,10 +1542,6 @@ int dsi_pll_set_clock_div(struct platform_device *dsidev,
 
 	if (dss_has_feature(FEAT_DSI_PLL_FREQSEL))
 		l = FLD_MOD(l, f, 4, 1);	/* DSI_PLL_FREQSEL */
-	l = FLD_MOD(l, cinfo->use_sys_clk ? 0 : 1,
-			11, 11);		/* DSI_PLL_CLKSEL */
-	l = FLD_MOD(l, cinfo->highfreq,
-			12, 12);		/* DSI_PLL_HIGHFREQ */
 	l = FLD_MOD(l, 1, 13, 13);		/* DSI_PLL_REFEN */
 	l = FLD_MOD(l, 0, 14, 14);		/* DSIPHY_CLKINEN */
 	l = FLD_MOD(l, 1, 20, 20);		/* DSI_HSDIVBYPASS */
@@ -1726,8 +1696,7 @@ static void dsi_dump_dsidev_clocks(struct platform_device *dsidev,
 
 	seq_printf(s,	"- DSI%d PLL -\n", dsi_module + 1);
 
-	seq_printf(s,	"dsi pll source = %s\n",
-			cinfo->use_sys_clk ? "dss_sys_clk" : "pclkfree");
+	seq_printf(s,	"dsi pll clkin\t%lu\n", cinfo->clkin);
 
 	seq_printf(s,	"Fint\t\t%-16luregn %u\n", cinfo->fint, cinfo->regn);
 
@@ -4285,13 +4254,11 @@ static int dsi_configure_dsi_clocks(struct omap_dss_device *dssdev)
 	struct dsi_clock_info cinfo;
 	int r;
 
-	/* we always use DSS_CLK_SYSCK as input clock */
-	cinfo.use_sys_clk = true;
 	cinfo.regn  = dssdev->clocks.dsi.regn;
 	cinfo.regm  = dssdev->clocks.dsi.regm;
 	cinfo.regm_dispc = dssdev->clocks.dsi.regm_dispc;
 	cinfo.regm_dsi = dssdev->clocks.dsi.regm_dsi;
-	r = dsi_calc_clock_rates(dssdev, &cinfo);
+	r = dsi_calc_clock_rates(dsidev, &cinfo);
 	if (r) {
 		DSSERR("Failed to calc dsi clocks\n");
 		return r;

drivers/video/omap2/dss/dss.h

@@ -150,9 +150,6 @@ struct dsi_clock_info {
 	u16 regm_dsi;	/* OMAP3: REGM4
 			 * OMAP4: REGM5 */
 	u16 lp_clk_div;
-
-	u8 highfreq;
-	bool use_sys_clk;
 };
 
 struct seq_file;