1 files changed, 539 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clock24xx.c b/arch/arm/mach-omap2/clock24xx.c
new file mode 100644
index 00000000000..ece32d8acba
--- /dev/null
+++ b/arch/arm/mach-omap2/clock24xx.c
@@ -0,0 +1,539 @@
+/*
+ *  linux/arch/arm/mach-omap2/clock.c
+ *
+ *  Copyright (C) 2005-2008 Texas Instruments, Inc.
+ *  Copyright (C) 2004-2008 Nokia Corporation
+ *
+ *  Contacts:
+ *  Richard Woodruff <r-woodruff2@ti.com>
+ *  Paul Walmsley
+ *
+ *  Based on earlier work by Tuukka Tikkanen, Tony Lindgren,
+ *  Gordon McNutt and RidgeRun, Inc.
+ *
+ * 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
+ * published by the Free Software Foundation.
+ */
+#undef DEBUG
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+
+#include <linux/io.h>
+#include <linux/cpufreq.h>
+
+#include <asm/arch/clock.h>
+#include <asm/arch/sram.h>
+#include <asm/div64.h>
+#include <asm/bitops.h>
+
+#include "memory.h"
+#include "clock.h"
+#include "clock24xx.h"
+#include "prm.h"
+#include "prm-regbits-24xx.h"
+#include "cm.h"
+#include "cm-regbits-24xx.h"
+
+/* CM_CLKEN_PLL.EN_{54,96}M_PLL options (24XX) */
+#define EN_APLL_STOPPED			0
+#define EN_APLL_LOCKED			3
+
+/* CM_CLKSEL1_PLL.APLLS_CLKIN options (24XX) */
+#define APLLS_CLKIN_19_2MHZ		0
+#define APLLS_CLKIN_13MHZ		2
+#define APLLS_CLKIN_12MHZ		3
+
+/* #define DOWN_VARIABLE_DPLL 1 */		/* Experimental */
+
+static struct prcm_config *curr_prcm_set;
+static struct clk *vclk;
+static struct clk *sclk;
+
+/*-------------------------------------------------------------------------
+ * Omap24xx specific clock functions
+ *-------------------------------------------------------------------------*/
+
+/* This actually returns the rate of core_ck, not dpll_ck. */
+static u32 omap2_get_dpll_rate_24xx(struct clk *tclk)
+{
+	long long dpll_clk;
+	u8 amult;
+
+	dpll_clk = omap2_get_dpll_rate(tclk);
+
+	amult = cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
+	amult &= OMAP24XX_CORE_CLK_SRC_MASK;
+	dpll_clk *= amult;
+
+	return dpll_clk;
+}
+
+static int omap2_enable_osc_ck(struct clk *clk)
+{
+	u32 pcc;
+
+	pcc = __raw_readl(OMAP24XX_PRCM_CLKSRC_CTRL);
+
+	__raw_writel(pcc & ~OMAP_AUTOEXTCLKMODE_MASK,
+		      OMAP24XX_PRCM_CLKSRC_CTRL);
+
+	return 0;
+}
+
+static void omap2_disable_osc_ck(struct clk *clk)
+{
+	u32 pcc;
+
+	pcc = __raw_readl(OMAP24XX_PRCM_CLKSRC_CTRL);
+
+	__raw_writel(pcc | OMAP_AUTOEXTCLKMODE_MASK,
+		      OMAP24XX_PRCM_CLKSRC_CTRL);
+}
+
+#ifdef OLD_CK
+/* Recalculate SYST_CLK */
+static void omap2_sys_clk_recalc(struct clk * clk)
+{
+	u32 div = PRCM_CLKSRC_CTRL;
+	div &= (1 << 7) | (1 << 6);	/* Test if ext clk divided by 1 or 2 */
+	div >>= clk->rate_offset;
+	clk->rate = (clk->parent->rate / div);
+	propagate_rate(clk);
+}
+#endif	/* OLD_CK */
+
+/* Enable an APLL if off */
+static int omap2_clk_fixed_enable(struct clk *clk)
+{
+	u32 cval, apll_mask;
+
+	apll_mask = EN_APLL_LOCKED << clk->enable_bit;
+
+	cval = cm_read_mod_reg(PLL_MOD, CM_CLKEN);
+
+	if ((cval & apll_mask) == apll_mask)
+		return 0;   /* apll already enabled */
+
+	cval &= ~apll_mask;
+	cval |= apll_mask;
+	cm_write_mod_reg(cval, PLL_MOD, CM_CLKEN);
+
+	if (clk == &apll96_ck)
+		cval = OMAP24XX_ST_96M_APLL;
+	else if (clk == &apll54_ck)
+		cval = OMAP24XX_ST_54M_APLL;
+
+	omap2_wait_clock_ready(OMAP_CM_REGADDR(PLL_MOD, CM_IDLEST), cval,
+			    clk->name);
+
+	/*
+	 * REVISIT: Should we return an error code if omap2_wait_clock_ready()
+	 * fails?
+	 */
+	return 0;
+}
+
+/* Stop APLL */
+static void omap2_clk_fixed_disable(struct clk *clk)
+{
+	u32 cval;
+
+	cval = cm_read_mod_reg(PLL_MOD, CM_CLKEN);
+	cval &= ~(EN_APLL_LOCKED << clk->enable_bit);
+	cm_write_mod_reg(cval, PLL_MOD, CM_CLKEN);
+}
+
+/*
+ * Uses the current prcm set to tell if a rate is valid.
+ * You can go slower, but not faster within a given rate set.
+ */
+static u32 omap2_dpll_round_rate(unsigned long target_rate)
+{
+	u32 high, low, core_clk_src;
+
+	core_clk_src = cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
+	core_clk_src &= OMAP24XX_CORE_CLK_SRC_MASK;
+
+	if (core_clk_src == CORE_CLK_SRC_DPLL) {	/* DPLL clockout */
+		high = curr_prcm_set->dpll_speed * 2;
+		low = curr_prcm_set->dpll_speed;
+	} else {				/* DPLL clockout x 2 */
+		high = curr_prcm_set->dpll_speed;
+		low = curr_prcm_set->dpll_speed / 2;
+	}
+
+#ifdef DOWN_VARIABLE_DPLL
+	if (target_rate > high)
+		return high;
+	else
+		return target_rate;
+#else
+	if (target_rate > low)
+		return high;
+	else
+		return low;
+#endif
+
+}
+
+static void omap2_dpll_recalc(struct clk *clk)
+{
+	clk->rate = omap2_get_dpll_rate_24xx(clk);
+
+	propagate_rate(clk);
+}
+
+static int omap2_reprogram_dpll(struct clk *clk, unsigned long rate)
+{
+	u32 cur_rate, low, mult, div, valid_rate, done_rate;
+	u32 bypass = 0;
+	struct prcm_config tmpset;
+	const struct dpll_data *dd;
+	unsigned long flags;
+	int ret = -EINVAL;
+
+	local_irq_save(flags);
+	cur_rate = omap2_get_dpll_rate_24xx(&dpll_ck);
+	mult = cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
+	mult &= OMAP24XX_CORE_CLK_SRC_MASK;
+
+	if ((rate == (cur_rate / 2)) && (mult == 2)) {
+		omap2_reprogram_sdrc(CORE_CLK_SRC_DPLL, 1);
+	} else if ((rate == (cur_rate * 2)) && (mult == 1)) {
+		omap2_reprogram_sdrc(CORE_CLK_SRC_DPLL_X2, 1);
+	} else if (rate != cur_rate) {
+		valid_rate = omap2_dpll_round_rate(rate);
+		if (valid_rate != rate)
+			goto dpll_exit;
+
+		if (mult == 1)
+			low = curr_prcm_set->dpll_speed;
+		else
+			low = curr_prcm_set->dpll_speed / 2;
+
+		dd = clk->dpll_data;
+		if (!dd)
+			goto dpll_exit;
+
+		tmpset.cm_clksel1_pll = __raw_readl(dd->mult_div1_reg);
+		tmpset.cm_clksel1_pll &= ~(dd->mult_mask |
+					   dd->div1_mask);
+		div = ((curr_prcm_set->xtal_speed / 1000000) - 1);
+		tmpset.cm_clksel2_pll = cm_read_mod_reg(PLL_MOD, CM_CLKSEL2);
+		tmpset.cm_clksel2_pll &= ~OMAP24XX_CORE_CLK_SRC_MASK;
+		if (rate > low) {
+			tmpset.cm_clksel2_pll |= CORE_CLK_SRC_DPLL_X2;
+			mult = ((rate / 2) / 1000000);
+			done_rate = CORE_CLK_SRC_DPLL_X2;
+		} else {
+			tmpset.cm_clksel2_pll |= CORE_CLK_SRC_DPLL;
+			mult = (rate / 1000000);
+			done_rate = CORE_CLK_SRC_DPLL;
+		}
+		tmpset.cm_clksel1_pll |= (div << __ffs(dd->mult_mask));
+		tmpset.cm_clksel1_pll |= (mult << __ffs(dd->div1_mask));
+
+		/* Worst case */
+		tmpset.base_sdrc_rfr = SDRC_RFR_CTRL_BYPASS;
+
+		if (rate == curr_prcm_set->xtal_speed)	/* If asking for 1-1 */
+			bypass = 1;
+
+		omap2_reprogram_sdrc(CORE_CLK_SRC_DPLL_X2, 1); /* For init_mem */
+
+		/* Force dll lock mode */
+		omap2_set_prcm(tmpset.cm_clksel1_pll, tmpset.base_sdrc_rfr,
+			       bypass);
+
+		/* Errata: ret dll entry state */
+		omap2_init_memory_params(omap2_dll_force_needed());
+		omap2_reprogram_sdrc(done_rate, 0);
+	}
+	omap2_dpll_recalc(&dpll_ck);
+	ret = 0;
+
+dpll_exit:
+	local_irq_restore(flags);
+	return(ret);
+}
+
+/**
+ * omap2_table_mpu_recalc - just return the MPU speed
+ * @clk: virt_prcm_set struct clk
+ *
+ * Set virt_prcm_set's rate to the mpu_speed field of the current PRCM set.
+ */
+static void omap2_table_mpu_recalc(struct clk *clk)
+{
+	clk->rate = curr_prcm_set->mpu_speed;
+}
+
+/*
+ * Look for a rate equal or less than the target rate given a configuration set.
+ *
+ * What's not entirely clear is "which" field represents the key field.
+ * Some might argue L3-DDR, others ARM, others IVA. This code is simple and
+ * just uses the ARM rates.
+ */
+static long omap2_round_to_table_rate(struct clk *clk, unsigned long rate)
+{
+	struct prcm_config *ptr;
+	long highest_rate;
+
+	if (clk != &virt_prcm_set)
+		return -EINVAL;
+
+	highest_rate = -EINVAL;
+
+	for (ptr = rate_table; ptr->mpu_speed; ptr++) {
+		if (!(ptr->flags & cpu_mask))
+			continue;
+		if (ptr->xtal_speed != sys_ck.rate)
+			continue;
+
+		highest_rate = ptr->mpu_speed;
+
+		/* Can check only after xtal frequency check */
+		if (ptr->mpu_speed <= rate)
+			break;
+	}
+	return highest_rate;
+}
+
+/* Sets basic clocks based on the specified rate */
+static int omap2_select_table_rate(struct clk *clk, unsigned long rate)
+{
+	u32 cur_rate, done_rate, bypass = 0, tmp;
+	struct prcm_config *prcm;
+	unsigned long found_speed = 0;
+	unsigned long flags;
+
+	if (clk != &virt_prcm_set)
+		return -EINVAL;
+
+	for (prcm = rate_table; prcm->mpu_speed; prcm++) {
+		if (!(prcm->flags & cpu_mask))
+			continue;
+
+		if (prcm->xtal_speed != sys_ck.rate)
+			continue;
+
+		if (prcm->mpu_speed <= rate) {
+			found_speed = prcm->mpu_speed;
+			break;
+		}
+	}
+
+	if (!found_speed) {
+		printk(KERN_INFO "Could not set MPU rate to %luMHz\n",
+		       rate / 1000000);
+		return -EINVAL;
+	}
+
+	curr_prcm_set = prcm;
+	cur_rate = omap2_get_dpll_rate_24xx(&dpll_ck);
+
+	if (prcm->dpll_speed == cur_rate / 2) {
+		omap2_reprogram_sdrc(CORE_CLK_SRC_DPLL, 1);
+	} else if (prcm->dpll_speed == cur_rate * 2) {
+		omap2_reprogram_sdrc(CORE_CLK_SRC_DPLL_X2, 1);
+	} else if (prcm->dpll_speed != cur_rate) {
+		local_irq_save(flags);
+
+		if (prcm->dpll_speed == prcm->xtal_speed)
+			bypass = 1;
+
+		if ((prcm->cm_clksel2_pll & OMAP24XX_CORE_CLK_SRC_MASK) ==
+		    CORE_CLK_SRC_DPLL_X2)
+			done_rate = CORE_CLK_SRC_DPLL_X2;
+		else
+			done_rate = CORE_CLK_SRC_DPLL;
+
+		/* MPU divider */
+		cm_write_mod_reg(prcm->cm_clksel_mpu, MPU_MOD, CM_CLKSEL);
+
+		/* dsp + iva1 div(2420), iva2.1(2430) */
+		cm_write_mod_reg(prcm->cm_clksel_dsp,
+				 OMAP24XX_DSP_MOD, CM_CLKSEL);
+
+		cm_write_mod_reg(prcm->cm_clksel_gfx, GFX_MOD, CM_CLKSEL);
+
+		/* Major subsystem dividers */
+		tmp = cm_read_mod_reg(CORE_MOD, CM_CLKSEL1) & OMAP24XX_CLKSEL_DSS2_MASK;
+		cm_write_mod_reg(prcm->cm_clksel1_core | tmp, CORE_MOD, CM_CLKSEL1);
+		if (cpu_is_omap2430())
+			cm_write_mod_reg(prcm->cm_clksel_mdm,
+					 OMAP2430_MDM_MOD, CM_CLKSEL);
+
+		/* x2 to enter init_mem */
+		omap2_reprogram_sdrc(CORE_CLK_SRC_DPLL_X2, 1);
+
+		omap2_set_prcm(prcm->cm_clksel1_pll, prcm->base_sdrc_rfr,
+			       bypass);
+
+		omap2_init_memory_params(omap2_dll_force_needed());
+		omap2_reprogram_sdrc(done_rate, 0);
+
+		local_irq_restore(flags);
+	}
+	omap2_dpll_recalc(&dpll_ck);
+
+	return 0;
+}
+
+static struct clk_functions omap2_clk_functions = {
+	.clk_enable		= omap2_clk_enable,
+	.clk_disable		= omap2_clk_disable,
+	.clk_round_rate		= omap2_clk_round_rate,
+	.clk_set_rate		= omap2_clk_set_rate,
+	.clk_set_parent		= omap2_clk_set_parent,
+	.clk_disable_unused	= omap2_clk_disable_unused,
+};
+
+static u32 omap2_get_apll_clkin(void)
+{
+	u32 aplls, sclk = 0;
+
+	aplls = cm_read_mod_reg(PLL_MOD, CM_CLKSEL1);
+	aplls &= OMAP24XX_APLLS_CLKIN_MASK;
+	aplls >>= OMAP24XX_APLLS_CLKIN_SHIFT;
+
+	if (aplls == APLLS_CLKIN_19_2MHZ)
+		sclk = 19200000;
+	else if (aplls == APLLS_CLKIN_13MHZ)
+		sclk = 13000000;
+	else if (aplls == APLLS_CLKIN_12MHZ)
+		sclk = 12000000;
+
+	return sclk;
+}
+
+static u32 omap2_get_sysclkdiv(void)
+{
+	u32 div;
+
+	div = __raw_readl(OMAP24XX_PRCM_CLKSRC_CTRL);
+	div &= OMAP_SYSCLKDIV_MASK;
+	div >>= OMAP_SYSCLKDIV_SHIFT;
+
+	return div;
+}
+
+static void omap2_osc_clk_recalc(struct clk *clk)
+{
+	clk->rate = omap2_get_apll_clkin() * omap2_get_sysclkdiv();
+	propagate_rate(clk);
+}
+
+static void omap2_sys_clk_recalc(struct clk *clk)
+{
+	clk->rate = clk->parent->rate / omap2_get_sysclkdiv();
+	propagate_rate(clk);
+}
+
+/*
+ * Set clocks for bypass mode for reboot to work.
+ */
+void omap2_clk_prepare_for_reboot(void)
+{
+	u32 rate;
+
+	if (vclk == NULL || sclk == NULL)
+		return;
+
+	rate = clk_get_rate(sclk);
+	clk_set_rate(vclk, rate);
+}
+
+/*
+ * Switch the MPU rate if specified on cmdline.
+ * We cannot do this early until cmdline is parsed.
+ */
+static int __init omap2_clk_arch_init(void)
+{
+	if (!mpurate)
+		return -EINVAL;
+
+	if (omap2_select_table_rate(&virt_prcm_set, mpurate))
+		printk(KERN_ERR "Could not find matching MPU rate\n");
+
+	recalculate_root_clocks();
+
+	printk(KERN_INFO "Switched to new clocking rate (Crystal/DPLL/MPU): "
+	       "%ld.%01ld/%ld/%ld MHz\n",
+	       (sys_ck.rate / 1000000), (sys_ck.rate / 100000) % 10,
+	       (dpll_ck.rate / 1000000), (mpu_ck.rate / 1000000)) ;
+
+	return 0;
+}
+arch_initcall(omap2_clk_arch_init);
+
+int __init omap2_clk_init(void)
+{
+	struct prcm_config *prcm;
+	struct clk **clkp;
+	u32 clkrate;
+
+	if (cpu_is_omap242x())
+		cpu_mask = RATE_IN_242X;
+	else if (cpu_is_omap2430())
+		cpu_mask = RATE_IN_243X;
+
+	clk_init(&omap2_clk_functions);
+
+	omap2_osc_clk_recalc(&osc_ck);
+	omap2_sys_clk_recalc(&sys_ck);
+
+	for (clkp = onchip_24xx_clks;
+	     clkp < onchip_24xx_clks + ARRAY_SIZE(onchip_24xx_clks);
+	     clkp++) {
+
+		if ((*clkp)->flags & CLOCK_IN_OMAP242X && cpu_is_omap2420()) {
+			clk_register(*clkp);
+			continue;
+		}
+
+		if ((*clkp)->flags & CLOCK_IN_OMAP243X && cpu_is_omap2430()) {
+			clk_register(*clkp);
+			continue;
+		}
+	}
+
+	/* Check the MPU rate set by bootloader */
+	clkrate = omap2_get_dpll_rate_24xx(&dpll_ck);
+	for (prcm = rate_table; prcm->mpu_speed; prcm++) {
+		if (!(prcm->flags & cpu_mask))
+			continue;
+		if (prcm->xtal_speed != sys_ck.rate)
+			continue;
+		if (prcm->dpll_speed <= clkrate)
+			 break;
+	}
+	curr_prcm_set = prcm;
+
+	recalculate_root_clocks();
+
+	printk(KERN_INFO "Clocking rate (Crystal/DPLL/MPU): "
+	       "%ld.%01ld/%ld/%ld MHz\n",
+	       (sys_ck.rate / 1000000), (sys_ck.rate / 100000) % 10,
+	       (dpll_ck.rate / 1000000), (mpu_ck.rate / 1000000)) ;
+
+	/*
+	 * Only enable those clocks we will need, let the drivers
+	 * enable other clocks as necessary
+	 */
+	clk_enable_init_clocks();
+
+	/* Avoid sleeping sleeping during omap2_clk_prepare_for_reboot() */
+	vclk = clk_get(NULL, "virt_prcm_set");
+	sclk = clk_get(NULL, "sys_ck");
+
+	return 0;
+}