davinci: major rework of clock, PLL, PSC infrastructure

This is a significant rework of the low-level clock, PLL and Power
Sleep Controller (PSC) implementation for the DaVinci family.  The
primary goal is to have better modeling if the hardware clocks and
features with the aim of DVFS functionality.

Highlights:
- model PLLs and all PLL-derived clocks
- model parent/child relationships of PLLs and clocks
- convert to new clkdev layer
- view clock frequency and refcount via /proc/davinci_clocks

Special thanks to significant contributions and testing by David
Brownell.

Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
diff --git a/arch/arm/mach-davinci/psc.c b/arch/arm/mach-davinci/psc.c
index 58754f0..c509883 100644
--- a/arch/arm/mach-davinci/psc.c
+++ b/arch/arm/mach-davinci/psc.c
@@ -23,6 +23,7 @@
 #include <linux/init.h>
 #include <linux/io.h>
 
+#include <mach/cputype.h>
 #include <mach/hardware.h>
 #include <mach/psc.h>
 #include <mach/mux.h>
@@ -36,76 +37,57 @@
 #define MDSTAT		0x800
 #define MDCTL		0xA00
 
-/* System control register offsets */
-#define VDD3P3V_PWDN	0x48
 
-static void davinci_psc_mux(unsigned int id)
+/* Return nonzero iff the domain's clock is active */
+int __init davinci_psc_is_clk_active(unsigned int id)
 {
-	switch (id) {
-	case DAVINCI_LPSC_ATA:
-		davinci_mux_peripheral(DAVINCI_MUX_HDIREN, 1);
-		davinci_mux_peripheral(DAVINCI_MUX_ATAEN, 1);
-		break;
-	case DAVINCI_LPSC_MMC_SD:
-		/* VDD power manupulations are done in U-Boot for CPMAC
-		 * so applies to MMC as well
-		 */
-		/*Set up the pull regiter for MMC */
-		davinci_writel(0, DAVINCI_SYSTEM_MODULE_BASE + VDD3P3V_PWDN);
-		davinci_mux_peripheral(DAVINCI_MUX_MSTK, 0);
-		break;
-	case DAVINCI_LPSC_I2C:
-		davinci_mux_peripheral(DAVINCI_MUX_I2C, 1);
-		break;
-	case DAVINCI_LPSC_McBSP:
-		davinci_mux_peripheral(DAVINCI_MUX_ASP, 1);
-		break;
-	default:
-		break;
-	}
+	void __iomem *psc_base = IO_ADDRESS(DAVINCI_PWR_SLEEP_CNTRL_BASE);
+	u32 mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
+
+	/* if clocked, state can be "Enable" or "SyncReset" */
+	return mdstat & BIT(12);
 }
 
 /* Enable or disable a PSC domain */
 void davinci_psc_config(unsigned int domain, unsigned int id, char enable)
 {
 	u32 epcpr, ptcmd, ptstat, pdstat, pdctl1, mdstat, mdctl, mdstat_mask;
+	void __iomem *psc_base = IO_ADDRESS(DAVINCI_PWR_SLEEP_CNTRL_BASE);
 
-	mdctl = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE + MDCTL + 4 * id);
+	mdctl = __raw_readl(psc_base + MDCTL + 4 * id);
 	if (enable)
 		mdctl |= 0x00000003;	/* Enable Module */
 	else
-		mdctl &= 0xFFFFFFF2;	/* Disable Module */
-	davinci_writel(mdctl, DAVINCI_PWR_SLEEP_CNTRL_BASE + MDCTL + 4 * id);
+		mdctl &= 0xFFFFFFE2;	/* Disable Module */
+	__raw_writel(mdctl, psc_base + MDCTL + 4 * id);
 
-	pdstat = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE + PDSTAT);
+	pdstat = __raw_readl(psc_base + PDSTAT);
 	if ((pdstat & 0x00000001) == 0) {
-		pdctl1 = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE + PDCTL1);
+		pdctl1 = __raw_readl(psc_base + PDCTL1);
 		pdctl1 |= 0x1;
-		davinci_writel(pdctl1, DAVINCI_PWR_SLEEP_CNTRL_BASE + PDCTL1);
+		__raw_writel(pdctl1, psc_base + PDCTL1);
 
 		ptcmd = 1 << domain;
-		davinci_writel(ptcmd, DAVINCI_PWR_SLEEP_CNTRL_BASE + PTCMD);
+		__raw_writel(ptcmd, psc_base + PTCMD);
 
 		do {
-			epcpr = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE +
-					      EPCPR);
+			epcpr = __raw_readl(psc_base + EPCPR);
 		} while ((((epcpr >> domain) & 1) == 0));
 
-		pdctl1 = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE + PDCTL1);
+		pdctl1 = __raw_readl(psc_base + PDCTL1);
 		pdctl1 |= 0x100;
-		davinci_writel(pdctl1, DAVINCI_PWR_SLEEP_CNTRL_BASE + PDCTL1);
+		__raw_writel(pdctl1, psc_base + PDCTL1);
 
 		do {
-			ptstat = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE +
+			ptstat = __raw_readl(psc_base +
 					       PTSTAT);
 		} while (!(((ptstat >> domain) & 1) == 0));
 	} else {
 		ptcmd = 1 << domain;
-		davinci_writel(ptcmd, DAVINCI_PWR_SLEEP_CNTRL_BASE + PTCMD);
+		__raw_writel(ptcmd, psc_base + PTCMD);
 
 		do {
-			ptstat = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE +
-					       PTSTAT);
+			ptstat = __raw_readl(psc_base + PTSTAT);
 		} while (!(((ptstat >> domain) & 1) == 0));
 	}
 
@@ -115,23 +97,6 @@
 		mdstat_mask = 0x2;
 
 	do {
-		mdstat = davinci_readl(DAVINCI_PWR_SLEEP_CNTRL_BASE +
-				       MDSTAT + 4 * id);
+		mdstat = __raw_readl(psc_base + MDSTAT + 4 * id);
 	} while (!((mdstat & 0x0000001F) == mdstat_mask));
-
-	if (enable)
-		davinci_psc_mux(id);
-}
-
-void __init davinci_psc_init(void)
-{
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_VPSSMSTR, 1);
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_VPSSSLV, 1);
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_TPCC, 1);
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_TPTC0, 1);
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_TPTC1, 1);
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_GPIO, 1);
-
-	/* Turn on WatchDog timer LPSC.	 Needed for RESET to work */
-	davinci_psc_config(DAVINCI_GPSC_ARMDOMAIN, DAVINCI_LPSC_TIMER2, 1);
 }