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-rw-r--r--arch/arm/mach-omap2/clock24xx.c539
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 000000000000..ece32d8acba4
--- /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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 05:38:52 +0000