| /* | 
 |  * OMAP2xxx DVFS virtual clock functions | 
 |  * | 
 |  * Copyright (C) 2005-2008 Texas Instruments, Inc. | 
 |  * Copyright (C) 2004-2010 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. | 
 |  * | 
 |  * XXX Some of this code should be replaceable by the upcoming OPP layer | 
 |  * code.  However, some notion of "rate set" is probably still necessary | 
 |  * for OMAP2xxx at least.  Rate sets should be generalized so they can be | 
 |  * used for any OMAP chip, not just OMAP2xxx.  In particular, Richard Woodruff | 
 |  * has in the past expressed a preference to use rate sets for OPP changes, | 
 |  * rather than dynamically recalculating the clock tree, so if someone wants | 
 |  * this badly enough to write the code to handle it, we should support it | 
 |  * as an option. | 
 |  */ | 
 | #undef DEBUG | 
 |  | 
 | #include <linux/kernel.h> | 
 | #include <linux/errno.h> | 
 | #include <linux/clk.h> | 
 | #include <linux/io.h> | 
 | #include <linux/cpufreq.h> | 
 | #include <linux/slab.h> | 
 |  | 
 | #include <plat/clock.h> | 
 | #include <plat/sram.h> | 
 | #include <plat/sdrc.h> | 
 |  | 
 | #include "clock.h" | 
 | #include "clock2xxx.h" | 
 | #include "opp2xxx.h" | 
 | #include "cm2xxx_3xxx.h" | 
 | #include "cm-regbits-24xx.h" | 
 |  | 
 | const struct prcm_config *curr_prcm_set; | 
 | const struct prcm_config *rate_table; | 
 |  | 
 | /** | 
 |  * 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. | 
 |  */ | 
 | unsigned long omap2_table_mpu_recalc(struct clk *clk) | 
 | { | 
 | 	return 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. | 
 |  */ | 
 | long omap2_round_to_table_rate(struct clk *clk, unsigned long rate) | 
 | { | 
 | 	const struct prcm_config *ptr; | 
 | 	long highest_rate; | 
 |  | 
 | 	highest_rate = -EINVAL; | 
 |  | 
 | 	for (ptr = rate_table; ptr->mpu_speed; ptr++) { | 
 | 		if (!(ptr->flags & cpu_mask)) | 
 | 			continue; | 
 | 		if (ptr->xtal_speed != sclk->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 */ | 
 | int omap2_select_table_rate(struct clk *clk, unsigned long rate) | 
 | { | 
 | 	u32 cur_rate, done_rate, bypass = 0, tmp; | 
 | 	const struct prcm_config *prcm; | 
 | 	unsigned long found_speed = 0; | 
 | 	unsigned long flags; | 
 |  | 
 | 	for (prcm = rate_table; prcm->mpu_speed; prcm++) { | 
 | 		if (!(prcm->flags & cpu_mask)) | 
 | 			continue; | 
 |  | 
 | 		if (prcm->xtal_speed != sclk->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 = omap2xxx_clk_get_core_rate(dclk); | 
 |  | 
 | 	if (prcm->dpll_speed == cur_rate / 2) { | 
 | 		omap2xxx_sdrc_reprogram(CORE_CLK_SRC_DPLL, 1); | 
 | 	} else if (prcm->dpll_speed == cur_rate * 2) { | 
 | 		omap2xxx_sdrc_reprogram(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 */ | 
 | 		omap2_cm_write_mod_reg(prcm->cm_clksel_mpu, MPU_MOD, CM_CLKSEL); | 
 |  | 
 | 		/* dsp + iva1 div(2420), iva2.1(2430) */ | 
 | 		omap2_cm_write_mod_reg(prcm->cm_clksel_dsp, | 
 | 				 OMAP24XX_DSP_MOD, CM_CLKSEL); | 
 |  | 
 | 		omap2_cm_write_mod_reg(prcm->cm_clksel_gfx, GFX_MOD, CM_CLKSEL); | 
 |  | 
 | 		/* Major subsystem dividers */ | 
 | 		tmp = omap2_cm_read_mod_reg(CORE_MOD, CM_CLKSEL1) & OMAP24XX_CLKSEL_DSS2_MASK; | 
 | 		omap2_cm_write_mod_reg(prcm->cm_clksel1_core | tmp, CORE_MOD, | 
 | 				 CM_CLKSEL1); | 
 |  | 
 | 		if (cpu_is_omap2430()) | 
 | 			omap2_cm_write_mod_reg(prcm->cm_clksel_mdm, | 
 | 					 OMAP2430_MDM_MOD, CM_CLKSEL); | 
 |  | 
 | 		/* x2 to enter omap2xxx_sdrc_init_params() */ | 
 | 		omap2xxx_sdrc_reprogram(CORE_CLK_SRC_DPLL_X2, 1); | 
 |  | 
 | 		omap2_set_prcm(prcm->cm_clksel1_pll, prcm->base_sdrc_rfr, | 
 | 			       bypass); | 
 |  | 
 | 		omap2xxx_sdrc_init_params(omap2xxx_sdrc_dll_is_unlocked()); | 
 | 		omap2xxx_sdrc_reprogram(done_rate, 0); | 
 |  | 
 | 		local_irq_restore(flags); | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | #ifdef CONFIG_CPU_FREQ | 
 | /* | 
 |  * Walk PRCM rate table and fillout cpufreq freq_table | 
 |  * XXX This should be replaced by an OPP layer in the near future | 
 |  */ | 
 | static struct cpufreq_frequency_table *freq_table; | 
 |  | 
 | void omap2_clk_init_cpufreq_table(struct cpufreq_frequency_table **table) | 
 | { | 
 | 	const struct prcm_config *prcm; | 
 | 	int i = 0; | 
 | 	int tbl_sz = 0; | 
 |  | 
 | 	if (!cpu_is_omap24xx()) | 
 | 		return; | 
 |  | 
 | 	for (prcm = rate_table; prcm->mpu_speed; prcm++) { | 
 | 		if (!(prcm->flags & cpu_mask)) | 
 | 			continue; | 
 | 		if (prcm->xtal_speed != sclk->rate) | 
 | 			continue; | 
 |  | 
 | 		/* don't put bypass rates in table */ | 
 | 		if (prcm->dpll_speed == prcm->xtal_speed) | 
 | 			continue; | 
 |  | 
 | 		tbl_sz++; | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * XXX Ensure that we're doing what CPUFreq expects for this error | 
 | 	 * case and the following one | 
 | 	 */ | 
 | 	if (tbl_sz == 0) { | 
 | 		pr_warning("%s: no matching entries in rate_table\n", | 
 | 			   __func__); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	/* Include the CPUFREQ_TABLE_END terminator entry */ | 
 | 	tbl_sz++; | 
 |  | 
 | 	freq_table = kzalloc(sizeof(struct cpufreq_frequency_table) * tbl_sz, | 
 | 			     GFP_ATOMIC); | 
 | 	if (!freq_table) { | 
 | 		pr_err("%s: could not kzalloc frequency table\n", __func__); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	for (prcm = rate_table; prcm->mpu_speed; prcm++) { | 
 | 		if (!(prcm->flags & cpu_mask)) | 
 | 			continue; | 
 | 		if (prcm->xtal_speed != sclk->rate) | 
 | 			continue; | 
 |  | 
 | 		/* don't put bypass rates in table */ | 
 | 		if (prcm->dpll_speed == prcm->xtal_speed) | 
 | 			continue; | 
 |  | 
 | 		freq_table[i].index = i; | 
 | 		freq_table[i].frequency = prcm->mpu_speed / 1000; | 
 | 		i++; | 
 | 	} | 
 |  | 
 | 	freq_table[i].index = i; | 
 | 	freq_table[i].frequency = CPUFREQ_TABLE_END; | 
 |  | 
 | 	*table = &freq_table[0]; | 
 | } | 
 |  | 
 | void omap2_clk_exit_cpufreq_table(struct cpufreq_frequency_table **table) | 
 | { | 
 | 	if (!cpu_is_omap24xx()) | 
 | 		return; | 
 |  | 
 | 	kfree(freq_table); | 
 | } | 
 |  | 
 | #endif |