ARM: OMAP2: Clockdomain: Integrate OMAP3 clocks with clockdomain code

This patch integrates the OMAP3 clock tree with the clockdomain code.
This patch:

- marks OMAP34xx clocks with their corresponding clockdomain.

- adds code to convert the clockdomain name to a clockdomain pointer in the
  struct clk during clk_register().

- modifies OMAP2 clock usecounting to call into the clockdomain code
  when clocks are enabled or disabled.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/clock.c

@@ -26,6 +26,7 @@
 #include <asm/io.h>
 
 #include <mach/clock.h>
+#include <mach/clockdomain.h>
 #include <mach/sram.h>
 #include <mach/cpu.h>
 #include <asm/div64.h>
@@ -62,9 +63,35 @@
 u8 cpu_mask;
 
 /*-------------------------------------------------------------------------
- * Omap2 specific clock functions
+ * OMAP2/3 specific clock functions
  *-------------------------------------------------------------------------*/
 
+/**
+ * omap2_init_clk_clkdm - look up a clockdomain name, store pointer in clk
+ * @clk: OMAP clock struct ptr to use
+ *
+ * Convert a clockdomain name stored in a struct clk 'clk' into a
+ * clockdomain pointer, and save it into the struct clk.  Intended to be
+ * called during clk_register().  No return value.
+ */
+void omap2_init_clk_clkdm(struct clk *clk)
+{
+	struct clockdomain *clkdm;
+
+	if (!clk->clkdm_name)
+		return;
+
+	clkdm = clkdm_lookup(clk->clkdm_name);
+	if (clkdm) {
+		pr_debug("clock: associated clk %s to clkdm %s\n",
+			 clk->name, clk->clkdm_name);
+		clk->clkdm = clkdm;
+	} else {
+		pr_debug("clock: could not associate clk %s to "
+			 "clkdm %s\n", clk->name, clk->clkdm_name);
+	}
+}
+
 /**
  * omap2_init_clksel_parent - set a clksel clk's parent field from the hardware
  * @clk: OMAP clock struct ptr to use
@@ -308,6 +335,9 @@ void omap2_clk_disable(struct clk *clk)
 		_omap2_clk_disable(clk);
 		if (likely((u32)clk->parent))
 			omap2_clk_disable(clk->parent);
+		if (clk->clkdm)
+			omap2_clkdm_clk_disable(clk->clkdm, clk);
+
 	}
 }
 
@@ -324,13 +354,21 @@ int omap2_clk_enable(struct clk *clk)
 			return ret;
 		}
 
+		if (clk->clkdm)
+			omap2_clkdm_clk_enable(clk->clkdm, clk);
+
 		ret = _omap2_clk_enable(clk);
 
-		if (unlikely(ret != 0) && clk->parent) {
+		if (unlikely(ret != 0)) {
+			if (clk->clkdm)
+				omap2_clkdm_clk_disable(clk->clkdm, clk);
+
+			if (clk->parent) {
 				omap2_clk_disable(clk->parent);
 				clk->usecount--;
 			}
 		}
+	}
 
 	return ret;
 }

arch/arm/mach-omap2/clock.h

@@ -36,6 +36,7 @@ void omap2_clk_disable_unused(struct clk *clk);
 #endif
 
 void omap2_clksel_recalc(struct clk *clk);
+void omap2_init_clk_clkdm(struct clk *clk);
 void omap2_init_clksel_parent(struct clk *clk);
 u32 omap2_clksel_get_divisor(struct clk *clk);
 u32 omap2_clksel_round_rate_div(struct clk *clk, unsigned long target_rate,

arch/arm/mach-omap2/clock34xx.c

@@ -489,8 +489,10 @@ int __init omap2_clk_init(void)
 	for (clkp = onchip_34xx_clks;
 	     clkp < onchip_34xx_clks + ARRAY_SIZE(onchip_34xx_clks);
 	     clkp++) {
-		if ((*clkp)->flags & cpu_clkflg)
+		if ((*clkp)->flags & cpu_clkflg) {
 			clk_register(*clkp);
+			omap2_init_clk_clkdm(*clkp);
+		}
 	}
 
 	/* REVISIT: Not yet ready for OMAP3 */

arch/arm/mach-omap2/clockdomains.h

@@ -168,12 +168,19 @@ static struct clockdomain sgx_clkdm = {
 	.omap_chip	= OMAP_CHIP_INIT(CHIP_IS_OMAP3430ES2),
 };
 
+/*
+ * The die-to-die clockdomain was documented in the 34xx ES1 TRM, but
+ * then that information was removed from the 34xx ES2+ TRM.  It is
+ * unclear whether the core is still there, but the clockdomain logic
+ * is there, and must be programmed to an appropriate state if the
+ * CORE clockdomain is to become inactive.
+ */
 static struct clockdomain d2d_clkdm = {
 	.name		= "d2d_clkdm",
 	.pwrdm_name	= "core_pwrdm",
 	.flags		= CLKDM_CAN_HWSUP,
 	.clktrctrl_mask = OMAP3430ES1_CLKTRCTRL_D2D_MASK,
-	.omap_chip	= OMAP_CHIP_INIT(CHIP_IS_OMAP3430ES1),
+	.omap_chip	= OMAP_CHIP_INIT(CHIP_IS_OMAP3430),
 };
 
 static struct clockdomain core_l3_34xx_clkdm = {