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>

arch/arm/Kconfig

@@ -586,6 +586,7 @@ config ARCH_DAVINCI
 	select HAVE_CLK
 	select ZONE_DMA
 	select HAVE_IDE
+	select COMMON_CLKDEV
 	help
 	  Support for TI's DaVinci platform.
 

arch/arm/mach-davinci/Kconfig

@@ -18,6 +18,18 @@ config MACH_DAVINCI_EVM
 	  Configure this option to specify the whether the board used
 	  for development is a DaVinci EVM
 
+config DAVINCI_RESET_CLOCKS
+	bool "Reset unused clocks during boot"
+	depends on ARCH_DAVINCI
+	help
+	  Say Y if you want to reset unused clocks during boot.
+	  This option saves power, but assumes all drivers are
+	  using the clock framework. Broken drivers that do not
+	  yet use clock framework may not work with this option.
+	  If you are booting from another operating system, you
+	  probably do not want this option enabled until your
+	  device drivers work properly.
+
 endmenu
 
 endif

arch/arm/mach-davinci/board-evm.c

@@ -406,8 +406,6 @@ davinci_evm_map_io(void)
 
 static __init void davinci_evm_init(void)
 {
-	davinci_psc_init();
-
 #if defined(CONFIG_BLK_DEV_PALMCHIP_BK3710) || \
     defined(CONFIG_BLK_DEV_PALMCHIP_BK3710_MODULE)
 #if defined(CONFIG_MTD_PHYSMAP) || \

arch/arm/mach-davinci/clock.h

 /*
  * TI DaVinci clock definitions
  *
- * Copyright (C) 2006 Texas Instruments.
+ * Copyright (C) 2006-2007 Texas Instruments.
+ * Copyright (C) 2008-2009 Deep Root Systems, LLC
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -11,23 +12,85 @@
 #ifndef __ARCH_ARM_DAVINCI_CLOCK_H
 #define __ARCH_ARM_DAVINCI_CLOCK_H
 
+#include <linux/list.h>
+#include <asm/clkdev.h>
+
+#define DAVINCI_PLL1_BASE 0x01c40800
+#define DAVINCI_PLL2_BASE 0x01c40c00
+#define MAX_PLL 2
+
+/* PLL/Reset register offsets */
+#define PLLCTL          0x100
+#define PLLCTL_PLLEN    BIT(0)
+#define PLLCTL_CLKMODE  BIT(8)
+
+#define PLLM		0x110
+#define PLLM_PLLM_MASK  0xff
+
+#define PREDIV          0x114
+#define PLLDIV1         0x118
+#define PLLDIV2         0x11c
+#define PLLDIV3         0x120
+#define POSTDIV         0x128
+#define BPDIV           0x12c
+#define PLLCMD		0x138
+#define PLLSTAT		0x13c
+#define PLLALNCTL	0x140
+#define PLLDCHANGE	0x144
+#define PLLCKEN		0x148
+#define PLLCKSTAT	0x14c
+#define PLLSYSTAT	0x150
+#define PLLDIV4         0x160
+#define PLLDIV5         0x164
+#define PLLDIV6         0x168
+#define PLLDIV7         0x16c
+#define PLLDIV8         0x170
+#define PLLDIV9         0x174
+#define PLLDIV_EN       BIT(15)
+#define PLLDIV_RATIO_MASK 0x1f
+
+struct pll_data {
+	u32 phys_base;
+	void __iomem *base;
+	u32 num;
+	u32 flags;
+	u32 input_rate;
+};
+#define PLL_HAS_PREDIV          0x01
+#define PLL_HAS_POSTDIV         0x02
+
 struct clk {
 	struct list_head	node;
 	struct module		*owner;
 	const char		*name;
-	unsigned int		*rate;
-	int			id;
-	__s8			usecount;
-	__u8			flags;
-	__u8			lpsc;
+	unsigned long		rate;
+	u8			usecount;
+	u8			flags;
+	u8			lpsc;
+	struct clk              *parent;
+	struct pll_data         *pll_data;
+	u32                     div_reg;
 };
 
 /* Clock flags */
-#define RATE_CKCTL		1
-#define RATE_FIXED		2
-#define RATE_PROPAGATES		4
-#define VIRTUAL_CLOCK		8
-#define ALWAYS_ENABLED		16
-#define ENABLE_REG_32BIT	32
+#define ALWAYS_ENABLED		BIT(1)
+#define CLK_PSC                 BIT(2)
+#define PSC_DSP                 BIT(3) /* PSC uses DSP domain, not ARM */
+#define CLK_PLL			BIT(4) /* PLL-derived clock */
+#define PRE_PLL                 BIT(5) /* source is before PLL mult/div */
+
+struct davinci_clk {
+	struct clk_lookup lk;
+};
+
+#define CLK(dev, con, ck) 		\
+	{				\
+		.lk = {			\
+			.dev_id = dev,	\
+			.con_id = con,	\
+			.clk = ck,	\
+		},			\
+	}
 
+int davinci_clk_init(struct davinci_clk *clocks);
 #endif

arch/arm/mach-davinci/include/mach/clkdev.h

+#ifndef __MACH_CLKDEV_H
+#define __MACH_CLKDEV_H
+
+static inline int __clk_get(struct clk *clk)
+{
+	return 1;
+}
+
+static inline void __clk_put(struct clk *clk)
+{
+}
+
+#endif

arch/arm/mach-davinci/include/mach/clock.h

@@ -17,6 +17,5 @@ struct clk;
 
 extern int clk_register(struct clk *clk);
 extern void clk_unregister(struct clk *clk);
-extern int davinci_clk_init(void);
 
 #endif

arch/arm/mach-davinci/include/mach/psc.h

@@ -38,8 +38,6 @@
 #define DAVINCI_LPSC_TPTC1          4
 #define DAVINCI_LPSC_EMAC           5
 #define DAVINCI_LPSC_EMAC_WRAPPER   6
-#define DAVINCI_LPSC_MDIO           7
-#define DAVINCI_LPSC_IEEE1394       8
 #define DAVINCI_LPSC_USB            9
 #define DAVINCI_LPSC_ATA            10
 #define DAVINCI_LPSC_VLYNQ          11
@@ -47,7 +45,6 @@
 #define DAVINCI_LPSC_DDR_EMIF       13
 #define DAVINCI_LPSC_AEMIF          14
 #define DAVINCI_LPSC_MMC_SD         15
-#define DAVINCI_LPSC_MEMSTICK       16
 #define DAVINCI_LPSC_McBSP          17
 #define DAVINCI_LPSC_I2C            18
 #define DAVINCI_LPSC_UART0          19
@@ -73,4 +70,54 @@
 #define DAVINCI_LPSC_GEM            39
 #define DAVINCI_LPSC_IMCOP          40
 
+#define DM355_LPSC_TIMER3		5
+#define DM355_LPSC_SPI1			6
+#define DM355_LPSC_MMC_SD1		7
+#define DM355_LPSC_McBSP1		8
+#define DM355_LPSC_PWM3			10
+#define DM355_LPSC_SPI2			11
+#define DM355_LPSC_RTO			12
+#define DM355_LPSC_VPSS_DAC		41
+
+/*
+ * LPSC Assignments
+ */
+#define DM646X_LPSC_ARM            0
+#define DM646X_LPSC_C64X_CPU       1
+#define DM646X_LPSC_HDVICP0        2
+#define DM646X_LPSC_HDVICP1        3
+#define DM646X_LPSC_TPCC           4
+#define DM646X_LPSC_TPTC0          5
+#define DM646X_LPSC_TPTC1          6
+#define DM646X_LPSC_TPTC2          7
+#define DM646X_LPSC_TPTC3          8
+#define DM646X_LPSC_PCI            13
+#define DM646X_LPSC_EMAC           14
+#define DM646X_LPSC_VDCE           15
+#define DM646X_LPSC_VPSSMSTR       16
+#define DM646X_LPSC_VPSSSLV        17
+#define DM646X_LPSC_TSIF0          18
+#define DM646X_LPSC_TSIF1          19
+#define DM646X_LPSC_DDR_EMIF       20
+#define DM646X_LPSC_AEMIF          21
+#define DM646X_LPSC_McASP0         22
+#define DM646X_LPSC_McASP1         23
+#define DM646X_LPSC_CRGEN0         24
+#define DM646X_LPSC_CRGEN1         25
+#define DM646X_LPSC_UART0          26
+#define DM646X_LPSC_UART1          27
+#define DM646X_LPSC_UART2          28
+#define DM646X_LPSC_PWM0           29
+#define DM646X_LPSC_PWM1           30
+#define DM646X_LPSC_I2C            31
+#define DM646X_LPSC_SPI            32
+#define DM646X_LPSC_GPIO           33
+#define DM646X_LPSC_TIMER0         34
+#define DM646X_LPSC_TIMER1         35
+#define DM646X_LPSC_ARM_INTC       45
+
+extern int davinci_psc_is_clk_active(unsigned int id);
+extern void davinci_psc_config(unsigned int domain, unsigned int id,
+			       char enable);
+
 #endif /* __ASM_ARCH_PSC_H */

arch/arm/mach-davinci/io.c

@@ -53,5 +53,4 @@ void __init davinci_map_common_io(void)
 
 void __init davinci_init_common_hw(void)
 {
-	davinci_clk_init();
 }

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 @@ void davinci_psc_config(unsigned int domain, unsigned int id, char enable)
 		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);
 }