diff options
Diffstat (limited to 'arch/arm/mach-omap2/clkt2xxx_virt_prcm_set.c')
| -rw-r--r-- | arch/arm/mach-omap2/clkt2xxx_virt_prcm_set.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clkt2xxx_virt_prcm_set.c b/arch/arm/mach-omap2/clkt2xxx_virt_prcm_set.c new file mode 100644 index 00000000000..3b1eac4d539 --- /dev/null +++ b/arch/arm/mach-omap2/clkt2xxx_virt_prcm_set.c @@ -0,0 +1,254 @@ +/* + * 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 <plat/clock.h> +#include <plat/sram.h> +#include <plat/sdrc.h> + +#include "clock.h" +#include "clock2xxx.h" +#include "opp2xxx.h" +#include "cm.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; + long sys_ck_rate; + + sys_ck_rate = clk_get_rate(sclk); + + 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 */ +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; + long sys_ck_rate; + + sys_ck_rate = clk_get_rate(sclk); + + 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 = 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 */ + 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 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; + long sys_ck_rate; + int i = 0; + int tbl_sz = 0; + + if (!cpu_is_omap24xx()) + return; + + sys_ck_rate = clk_get_rate(sclk); + + for (prcm = rate_table; prcm->mpu_speed; prcm++) { + if (!(prcm->flags & cpu_mask)) + continue; + if (prcm->xtal_speed != sys_ck_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 != sys_ck_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 |