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-rw-r--r--arch/arm/mach-mxs/clock-mx23.c526
1 files changed, 526 insertions, 0 deletions
diff --git a/arch/arm/mach-mxs/clock-mx23.c b/arch/arm/mach-mxs/clock-mx23.c
new file mode 100644
index 00000000000..8f5a19ab558
--- /dev/null
+++ b/arch/arm/mach-mxs/clock-mx23.c
@@ -0,0 +1,526 @@
+/*
+ * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+
+#include <asm/clkdev.h>
+#include <asm/div64.h>
+
+#include <mach/mx23.h>
+#include <mach/common.h>
+#include <mach/clock.h>
+
+#include "regs-clkctrl-mx23.h"
+
+#define CLKCTRL_BASE_ADDR MX23_IO_ADDRESS(MX23_CLKCTRL_BASE_ADDR)
+#define DIGCTRL_BASE_ADDR MX23_IO_ADDRESS(MX23_DIGCTL_BASE_ADDR)
+
+#define PARENT_RATE_SHIFT 8
+
+static int _raw_clk_enable(struct clk *clk)
+{
+ u32 reg;
+
+ if (clk->enable_reg) {
+ reg = __raw_readl(clk->enable_reg);
+ reg &= ~(1 << clk->enable_shift);
+ __raw_writel(reg, clk->enable_reg);
+ }
+
+ return 0;
+}
+
+static void _raw_clk_disable(struct clk *clk)
+{
+ u32 reg;
+
+ if (clk->enable_reg) {
+ reg = __raw_readl(clk->enable_reg);
+ reg |= 1 << clk->enable_shift;
+ __raw_writel(reg, clk->enable_reg);
+ }
+}
+
+/*
+ * ref_xtal_clk
+ */
+static unsigned long ref_xtal_clk_get_rate(struct clk *clk)
+{
+ return 24000000;
+}
+
+static struct clk ref_xtal_clk = {
+ .get_rate = ref_xtal_clk_get_rate,
+};
+
+/*
+ * pll_clk
+ */
+static unsigned long pll_clk_get_rate(struct clk *clk)
+{
+ return 480000000;
+}
+
+static int pll_clk_enable(struct clk *clk)
+{
+ __raw_writel(BM_CLKCTRL_PLLCTRL0_POWER |
+ BM_CLKCTRL_PLLCTRL0_EN_USB_CLKS,
+ CLKCTRL_BASE_ADDR + HW_CLKCTRL_PLLCTRL0_SET);
+
+ /* Only a 10us delay is need. PLLCTRL1 LOCK bitfied is only a timer
+ * and is incorrect (excessive). Per definition of the PLLCTRL0
+ * POWER field, waiting at least 10us.
+ */
+ udelay(10);
+
+ return 0;
+}
+
+static void pll_clk_disable(struct clk *clk)
+{
+ __raw_writel(BM_CLKCTRL_PLLCTRL0_POWER |
+ BM_CLKCTRL_PLLCTRL0_EN_USB_CLKS,
+ CLKCTRL_BASE_ADDR + HW_CLKCTRL_PLLCTRL0_CLR);
+}
+
+static struct clk pll_clk = {
+ .get_rate = pll_clk_get_rate,
+ .enable = pll_clk_enable,
+ .disable = pll_clk_disable,
+ .parent = &ref_xtal_clk,
+};
+
+/*
+ * ref_clk
+ */
+#define _CLK_GET_RATE_REF(name, sr, ss) \
+static unsigned long name##_get_rate(struct clk *clk) \
+{ \
+ unsigned long parent_rate; \
+ u32 reg, div; \
+ \
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##sr); \
+ div = (reg >> BP_CLKCTRL_##sr##_##ss##FRAC) & 0x3f; \
+ parent_rate = clk_get_rate(clk->parent); \
+ \
+ return SH_DIV((parent_rate >> PARENT_RATE_SHIFT) * 18, \
+ div, PARENT_RATE_SHIFT); \
+}
+
+_CLK_GET_RATE_REF(ref_cpu_clk, FRAC, CPU)
+_CLK_GET_RATE_REF(ref_emi_clk, FRAC, EMI)
+_CLK_GET_RATE_REF(ref_pix_clk, FRAC, PIX)
+_CLK_GET_RATE_REF(ref_io_clk, FRAC, IO)
+
+#define _DEFINE_CLOCK_REF(name, er, es) \
+ static struct clk name = { \
+ .enable_reg = CLKCTRL_BASE_ADDR + HW_CLKCTRL_##er, \
+ .enable_shift = BP_CLKCTRL_##er##_CLKGATE##es, \
+ .get_rate = name##_get_rate, \
+ .enable = _raw_clk_enable, \
+ .disable = _raw_clk_disable, \
+ .parent = &pll_clk, \
+ }
+
+_DEFINE_CLOCK_REF(ref_cpu_clk, FRAC, CPU);
+_DEFINE_CLOCK_REF(ref_emi_clk, FRAC, EMI);
+_DEFINE_CLOCK_REF(ref_pix_clk, FRAC, PIX);
+_DEFINE_CLOCK_REF(ref_io_clk, FRAC, IO);
+
+/*
+ * General clocks
+ *
+ * clk_get_rate
+ */
+static unsigned long rtc_clk_get_rate(struct clk *clk)
+{
+ /* ref_xtal_clk is implemented as the only parent */
+ return clk_get_rate(clk->parent) / 768;
+}
+
+static unsigned long clk32k_clk_get_rate(struct clk *clk)
+{
+ return clk->parent->get_rate(clk->parent) / 750;
+}
+
+#define _CLK_GET_RATE(name, rs) \
+static unsigned long name##_get_rate(struct clk *clk) \
+{ \
+ u32 reg, div; \
+ \
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##rs); \
+ \
+ if (clk->parent == &ref_xtal_clk) \
+ div = (reg & BM_CLKCTRL_##rs##_DIV_XTAL) >> \
+ BP_CLKCTRL_##rs##_DIV_XTAL; \
+ else \
+ div = (reg & BM_CLKCTRL_##rs##_DIV_##rs) >> \
+ BP_CLKCTRL_##rs##_DIV_##rs; \
+ \
+ if (!div) \
+ return -EINVAL; \
+ \
+ return clk_get_rate(clk->parent) / div; \
+}
+
+_CLK_GET_RATE(cpu_clk, CPU)
+_CLK_GET_RATE(emi_clk, EMI)
+
+#define _CLK_GET_RATE1(name, rs) \
+static unsigned long name##_get_rate(struct clk *clk) \
+{ \
+ u32 reg, div; \
+ \
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##rs); \
+ div = (reg & BM_CLKCTRL_##rs##_DIV) >> BP_CLKCTRL_##rs##_DIV; \
+ \
+ if (!div) \
+ return -EINVAL; \
+ \
+ return clk_get_rate(clk->parent) / div; \
+}
+
+_CLK_GET_RATE1(hbus_clk, HBUS)
+_CLK_GET_RATE1(xbus_clk, XBUS)
+_CLK_GET_RATE1(ssp_clk, SSP)
+_CLK_GET_RATE1(gpmi_clk, GPMI)
+_CLK_GET_RATE1(lcdif_clk, PIX)
+
+#define _CLK_GET_RATE_STUB(name) \
+static unsigned long name##_get_rate(struct clk *clk) \
+{ \
+ return clk_get_rate(clk->parent); \
+}
+
+_CLK_GET_RATE_STUB(uart_clk)
+_CLK_GET_RATE_STUB(audio_clk)
+_CLK_GET_RATE_STUB(pwm_clk)
+
+/*
+ * clk_set_rate
+ */
+static int cpu_clk_set_rate(struct clk *clk, unsigned long rate)
+{
+ u32 reg, bm_busy, div_max, d, f, div, frac;
+ unsigned long diff, parent_rate, calc_rate;
+ int i;
+
+ parent_rate = clk_get_rate(clk->parent);
+
+ if (clk->parent == &ref_xtal_clk) {
+ div_max = BM_CLKCTRL_CPU_DIV_XTAL >> BP_CLKCTRL_CPU_DIV_XTAL;
+ bm_busy = BM_CLKCTRL_CPU_BUSY_REF_XTAL;
+ div = DIV_ROUND_UP(parent_rate, rate);
+ if (div == 0 || div > div_max)
+ return -EINVAL;
+ } else {
+ div_max = BM_CLKCTRL_CPU_DIV_CPU >> BP_CLKCTRL_CPU_DIV_CPU;
+ bm_busy = BM_CLKCTRL_CPU_BUSY_REF_CPU;
+ rate >>= PARENT_RATE_SHIFT;
+ parent_rate >>= PARENT_RATE_SHIFT;
+ diff = parent_rate;
+ div = frac = 1;
+ for (d = 1; d <= div_max; d++) {
+ f = parent_rate * 18 / d / rate;
+ if ((parent_rate * 18 / d) % rate)
+ f++;
+ if (f < 18 || f > 35)
+ continue;
+
+ calc_rate = parent_rate * 18 / f / d;
+ if (calc_rate > rate)
+ continue;
+
+ if (rate - calc_rate < diff) {
+ frac = f;
+ div = d;
+ diff = rate - calc_rate;
+ }
+
+ if (diff == 0)
+ break;
+ }
+
+ if (diff == parent_rate)
+ return -EINVAL;
+
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_FRAC);
+ reg &= ~BM_CLKCTRL_FRAC_CPUFRAC;
+ reg |= frac;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_FRAC);
+ }
+
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU);
+ reg &= ~BM_CLKCTRL_CPU_DIV_CPU;
+ reg |= div << BP_CLKCTRL_CPU_DIV_CPU;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU);
+
+ for (i = 10000; i; i--)
+ if (!(__raw_readl(CLKCTRL_BASE_ADDR +
+ HW_CLKCTRL_CPU) & bm_busy))
+ break;
+ if (!i) {
+ pr_err("%s: divider writing timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+#define _CLK_SET_RATE(name, dr) \
+static int name##_set_rate(struct clk *clk, unsigned long rate) \
+{ \
+ u32 reg, div_max, div; \
+ unsigned long parent_rate; \
+ int i; \
+ \
+ parent_rate = clk_get_rate(clk->parent); \
+ div_max = BM_CLKCTRL_##dr##_DIV >> BP_CLKCTRL_##dr##_DIV; \
+ \
+ div = DIV_ROUND_UP(parent_rate, rate); \
+ if (div == 0 || div > div_max) \
+ return -EINVAL; \
+ \
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_##dr); \
+ reg &= ~BM_CLKCTRL_##dr##_DIV; \
+ reg |= div << BP_CLKCTRL_##dr##_DIV; \
+ if (reg | (1 << clk->enable_shift)) { \
+ pr_err("%s: clock is gated\n", __func__); \
+ return -EINVAL; \
+ } \
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_##dr); \
+ \
+ for (i = 10000; i; i--) \
+ if (!(__raw_readl(CLKCTRL_BASE_ADDR + \
+ HW_CLKCTRL_##dr) & BM_CLKCTRL_##dr##_BUSY)) \
+ break; \
+ if (!i) { \
+ pr_err("%s: divider writing timeout\n", __func__); \
+ return -ETIMEDOUT; \
+ } \
+ \
+ return 0; \
+}
+
+_CLK_SET_RATE(xbus_clk, XBUS)
+_CLK_SET_RATE(ssp_clk, SSP)
+_CLK_SET_RATE(gpmi_clk, GPMI)
+_CLK_SET_RATE(lcdif_clk, PIX)
+
+#define _CLK_SET_RATE_STUB(name) \
+static int name##_set_rate(struct clk *clk, unsigned long rate) \
+{ \
+ return -EINVAL; \
+}
+
+_CLK_SET_RATE_STUB(emi_clk)
+_CLK_SET_RATE_STUB(uart_clk)
+_CLK_SET_RATE_STUB(audio_clk)
+_CLK_SET_RATE_STUB(pwm_clk)
+_CLK_SET_RATE_STUB(clk32k_clk)
+
+/*
+ * clk_set_parent
+ */
+#define _CLK_SET_PARENT(name, bit) \
+static int name##_set_parent(struct clk *clk, struct clk *parent) \
+{ \
+ if (parent != clk->parent) { \
+ __raw_writel(BM_CLKCTRL_CLKSEQ_BYPASS_##bit, \
+ HW_CLKCTRL_CLKSEQ_TOG); \
+ clk->parent = parent; \
+ } \
+ \
+ return 0; \
+}
+
+_CLK_SET_PARENT(cpu_clk, CPU)
+_CLK_SET_PARENT(emi_clk, EMI)
+_CLK_SET_PARENT(ssp_clk, SSP)
+_CLK_SET_PARENT(gpmi_clk, GPMI)
+_CLK_SET_PARENT(lcdif_clk, PIX)
+
+#define _CLK_SET_PARENT_STUB(name) \
+static int name##_set_parent(struct clk *clk, struct clk *parent) \
+{ \
+ if (parent != clk->parent) \
+ return -EINVAL; \
+ else \
+ return 0; \
+}
+
+_CLK_SET_PARENT_STUB(uart_clk)
+_CLK_SET_PARENT_STUB(audio_clk)
+_CLK_SET_PARENT_STUB(pwm_clk)
+_CLK_SET_PARENT_STUB(clk32k_clk)
+
+/*
+ * clk definition
+ */
+static struct clk cpu_clk = {
+ .get_rate = cpu_clk_get_rate,
+ .set_rate = cpu_clk_set_rate,
+ .set_parent = cpu_clk_set_parent,
+ .parent = &ref_cpu_clk,
+};
+
+static struct clk hbus_clk = {
+ .get_rate = hbus_clk_get_rate,
+ .parent = &cpu_clk,
+};
+
+static struct clk xbus_clk = {
+ .get_rate = xbus_clk_get_rate,
+ .set_rate = xbus_clk_set_rate,
+ .parent = &ref_xtal_clk,
+};
+
+static struct clk rtc_clk = {
+ .get_rate = rtc_clk_get_rate,
+ .parent = &ref_xtal_clk,
+};
+
+/* usb_clk gate is controlled in DIGCTRL other than CLKCTRL */
+static struct clk usb_clk = {
+ .enable_reg = DIGCTRL_BASE_ADDR,
+ .enable_shift = 2,
+ .enable = _raw_clk_enable,
+ .disable = _raw_clk_disable,
+ .parent = &pll_clk,
+};
+
+#define _DEFINE_CLOCK(name, er, es, p) \
+ static struct clk name = { \
+ .enable_reg = CLKCTRL_BASE_ADDR + HW_CLKCTRL_##er, \
+ .enable_shift = BP_CLKCTRL_##er##_##es, \
+ .get_rate = name##_get_rate, \
+ .set_rate = name##_set_rate, \
+ .set_parent = name##_set_parent, \
+ .enable = _raw_clk_enable, \
+ .disable = _raw_clk_disable, \
+ .parent = p, \
+ }
+
+_DEFINE_CLOCK(emi_clk, EMI, CLKGATE, &ref_xtal_clk);
+_DEFINE_CLOCK(ssp_clk, SSP, CLKGATE, &ref_xtal_clk);
+_DEFINE_CLOCK(gpmi_clk, GPMI, CLKGATE, &ref_xtal_clk);
+_DEFINE_CLOCK(lcdif_clk, PIX, CLKGATE, &ref_xtal_clk);
+_DEFINE_CLOCK(uart_clk, XTAL, UART_CLK_GATE, &ref_xtal_clk);
+_DEFINE_CLOCK(audio_clk, XTAL, FILT_CLK24M_GATE, &ref_xtal_clk);
+_DEFINE_CLOCK(pwm_clk, XTAL, PWM_CLK24M_GATE, &ref_xtal_clk);
+_DEFINE_CLOCK(clk32k_clk, XTAL, TIMROT_CLK32K_GATE, &ref_xtal_clk);
+
+#define _REGISTER_CLOCK(d, n, c) \
+ { \
+ .dev_id = d, \
+ .con_id = n, \
+ .clk = &c, \
+ },
+
+static struct clk_lookup lookups[] = {
+ _REGISTER_CLOCK("mxs-duart.0", NULL, uart_clk)
+ _REGISTER_CLOCK("rtc", NULL, rtc_clk)
+ _REGISTER_CLOCK(NULL, "hclk", hbus_clk)
+ _REGISTER_CLOCK(NULL, "xclk", xbus_clk)
+ _REGISTER_CLOCK(NULL, "usb", usb_clk)
+ _REGISTER_CLOCK(NULL, "audio", audio_clk)
+ _REGISTER_CLOCK(NULL, "pwm", pwm_clk)
+};
+
+static int clk_misc_init(void)
+{
+ u32 reg;
+ int i;
+
+ /* Fix up parent per register setting */
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_CLKSEQ);
+ cpu_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_CPU) ?
+ &ref_xtal_clk : &ref_cpu_clk;
+ emi_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_EMI) ?
+ &ref_xtal_clk : &ref_emi_clk;
+ ssp_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_SSP) ?
+ &ref_xtal_clk : &ref_io_clk;
+ gpmi_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_GPMI) ?
+ &ref_xtal_clk : &ref_io_clk;
+ lcdif_clk.parent = (reg & BM_CLKCTRL_CLKSEQ_BYPASS_PIX) ?
+ &ref_xtal_clk : &ref_pix_clk;
+
+ /* Use int div over frac when both are available */
+ __raw_writel(BM_CLKCTRL_CPU_DIV_XTAL_FRAC_EN,
+ CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU_CLR);
+ __raw_writel(BM_CLKCTRL_CPU_DIV_CPU_FRAC_EN,
+ CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU_CLR);
+ __raw_writel(BM_CLKCTRL_HBUS_DIV_FRAC_EN,
+ CLKCTRL_BASE_ADDR + HW_CLKCTRL_HBUS_CLR);
+
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_XBUS);
+ reg &= ~BM_CLKCTRL_XBUS_DIV_FRAC_EN;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_XBUS);
+
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_SSP);
+ reg &= ~BM_CLKCTRL_SSP_DIV_FRAC_EN;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_SSP);
+
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_GPMI);
+ reg &= ~BM_CLKCTRL_GPMI_DIV_FRAC_EN;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_GPMI);
+
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_PIX);
+ reg &= ~BM_CLKCTRL_PIX_DIV_FRAC_EN;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_PIX);
+
+ /*
+ * Set safe hbus clock divider. A divider of 3 ensure that
+ * the Vddd voltage required for the cpu clock is sufficiently
+ * high for the hbus clock.
+ */
+ reg = __raw_readl(CLKCTRL_BASE_ADDR + HW_CLKCTRL_HBUS);
+ reg &= BM_CLKCTRL_HBUS_DIV;
+ reg |= 3 << BP_CLKCTRL_HBUS_DIV;
+ __raw_writel(reg, CLKCTRL_BASE_ADDR + HW_CLKCTRL_HBUS);
+
+ for (i = 10000; i; i--)
+ if (!(__raw_readl(CLKCTRL_BASE_ADDR +
+ HW_CLKCTRL_HBUS) & BM_CLKCTRL_HBUS_BUSY))
+ break;
+ if (!i) {
+ pr_err("%s: divider writing timeout\n", __func__);
+ return -ETIMEDOUT;
+ }
+
+ /* Gate off cpu clock in WFI for power saving */
+ __raw_writel(BM_CLKCTRL_CPU_INTERRUPT_WAIT,
+ CLKCTRL_BASE_ADDR + HW_CLKCTRL_CPU_SET);
+
+ return 0;
+}
+
+int __init mx23_clocks_init(void)
+{
+ clk_misc_init();
+
+ clkdev_add_table(lookups, ARRAY_SIZE(lookups));
+
+ mxs_timer_init(&clk32k_clk, MX23_INT_TIMER0);
+
+ return 0;
+}