arm: msm: add cpu frequency controls

This adds acpuclock-arm11.c from Google. This provides control
over the cpu frequency for arm11 cpu's.

This has shared authorship between Google, and Qualcomm. Most
of it was written by Mike Chan at Google.

Signed-off-by: Daniel Walker <dwalker@codeaurora.org>

4 files changed, 567 insertions, 0 deletions

diff --git a/arch/arm/mach-msm/Makefile b/arch/arm/mach-msm/Makefile
index 91e6f5c95dc1..0cb523fe3b3e 100644
--- a/arch/arm/mach-msm/Makefile
+++ b/arch/arm/mach-msm/Makefile
@@ -2,6 +2,7 @@ obj-y += io.o idle.o irq.o timer.o dma.o
 obj-y += devices.o
 obj-y += proc_comm.o
 obj-y += vreg.o
+obj-y += acpuclock-arm11.o
 obj-y += clock.o clock-7x01a.o
 
 obj-$(CONFIG_MACH_HALIBUT) += board-halibut.o
diff --git a/arch/arm/mach-msm/acpuclock-arm11.c b/arch/arm/mach-msm/acpuclock-arm11.c
new file mode 100644
index 000000000000..f9c9035bd9bb
--- /dev/null
+++ b/arch/arm/mach-msm/acpuclock-arm11.c
@@ -0,0 +1,523 @@
+/* arch/arm/mach-msm/acpuclock.c
+ *
+ * MSM architecture clock driver
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (c) 2007 QUALCOMM Incorporated
+ * Author: San Mehat <san@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
+#include <linux/mutex.h>
+#include <linux/io.h>
+#include <mach/board.h>
+#include <mach/msm_iomap.h>
+
+#include "proc_comm.h"
+#include "acpuclock.h"
+
+
+#define A11S_CLK_CNTL_ADDR (MSM_CSR_BASE + 0x100)
+#define A11S_CLK_SEL_ADDR (MSM_CSR_BASE + 0x104)
+#define A11S_VDD_SVS_PLEVEL_ADDR (MSM_CSR_BASE + 0x124)
+
+/*
+ * ARM11 clock configuration for specific ACPU speeds
+ */
+
+#define ACPU_PLL_TCXO   -1
+#define ACPU_PLL_0      0
+#define ACPU_PLL_1      1
+#define ACPU_PLL_2      2
+#define ACPU_PLL_3      3
+
+#define PERF_SWITCH_DEBUG 0
+#define PERF_SWITCH_STEP_DEBUG 0
+
+struct clock_state
+{
+        struct clkctl_acpu_speed        *current_speed;
+        struct mutex                    lock;
+        uint32_t                        acpu_switch_time_us;
+        uint32_t                        max_speed_delta_khz;
+        uint32_t                        vdd_switch_time_us;
+        unsigned long                   power_collapse_khz;
+        unsigned long                   wait_for_irq_khz;
+};
+
+static struct clk *ebi1_clk;
+static struct clock_state drv_state = { 0 };
+
+static void __init acpuclk_init(void);
+
+/* MSM7201A Levels 3-6 all correspond to 1.2V, level 7 corresponds to 1.325V. */
+enum {
+        VDD_0 = 0,
+        VDD_1 = 1,
+        VDD_2 = 2,
+        VDD_3 = 3,
+        VDD_4 = 3,
+        VDD_5 = 3,
+        VDD_6 = 3,
+        VDD_7 = 7,
+        VDD_END
+};
+
+struct clkctl_acpu_speed {
+        unsigned int    a11clk_khz;
+        int             pll;
+        unsigned int    a11clk_src_sel;
+        unsigned int    a11clk_src_div;
+        unsigned int    ahbclk_khz;
+        unsigned int    ahbclk_div;
+        int             vdd;
+        unsigned int    axiclk_khz;
+        unsigned long   lpj; /* loops_per_jiffy */
+/* Index in acpu_freq_tbl[] for steppings. */
+        short           down;
+        short           up;
+};
+
+/*
+ * ACPU speed table. Complete table is shown but certain speeds are commented
+ * out to optimized speed switching. Initalize loops_per_jiffy to 0.
+ *
+ * Table stepping up/down is optimized for 256mhz jumps while staying on the
+ * same PLL.
+ */
+#if (0)
+static struct clkctl_acpu_speed  acpu_freq_tbl[] = {
+        { 19200, ACPU_PLL_TCXO, 0, 0, 19200, 0, VDD_0, 30720, 0, 0, 8 },
+        { 61440, ACPU_PLL_0,  4, 3, 61440,  0, VDD_0, 30720,  0, 0, 8 },
+        { 81920, ACPU_PLL_0,  4, 2, 40960,  1, VDD_0, 61440,  0, 0, 8 },
+        { 96000, ACPU_PLL_1,  1, 7, 48000,  1, VDD_0, 61440,  0, 0, 9 },
+        { 122880, ACPU_PLL_0, 4, 1, 61440,  1, VDD_3, 61440,  0, 0, 8 },
+        { 128000, ACPU_PLL_1, 1, 5, 64000,  1, VDD_3, 61440,  0, 0, 12 },
+        { 176000, ACPU_PLL_2, 2, 5, 88000,  1, VDD_3, 61440,  0, 0, 11 },
+        { 192000, ACPU_PLL_1, 1, 3, 64000,  2, VDD_3, 61440,  0, 0, 12 },
+        { 245760, ACPU_PLL_0, 4, 0, 81920,  2, VDD_4, 61440,  0, 0, 12 },
+        { 256000, ACPU_PLL_1, 1, 2, 128000, 2, VDD_5, 128000, 0, 0, 12 },
+        { 264000, ACPU_PLL_2, 2, 3, 88000,  2, VDD_5, 128000, 0, 6, 13 },
+        { 352000, ACPU_PLL_2, 2, 2, 88000,  3, VDD_5, 128000, 0, 6, 13 },
+        { 384000, ACPU_PLL_1, 1, 1, 128000, 2, VDD_6, 128000, 0, 5, -1 },
+        { 528000, ACPU_PLL_2, 2, 1, 132000, 3, VDD_7, 128000, 0, 11, -1 },
+        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
+};
+#else /* Table of freq we currently use. */
+static struct clkctl_acpu_speed  acpu_freq_tbl[] = {
+        { 19200, ACPU_PLL_TCXO, 0, 0, 19200, 0, VDD_0, 30720, 0, 0, 4 },
+        { 122880, ACPU_PLL_0, 4, 1, 61440, 1, VDD_3, 61440, 0, 0, 4 },
+        { 128000, ACPU_PLL_1, 1, 5, 64000, 1, VDD_3, 61440, 0, 0, 6 },
+        { 176000, ACPU_PLL_2, 2, 5, 88000, 1, VDD_3, 61440, 0, 0, 5 },
+        { 245760, ACPU_PLL_0, 4, 0, 81920, 2, VDD_4, 61440, 0, 0, 5 },
+        { 352000, ACPU_PLL_2, 2, 2, 88000, 3, VDD_5, 128000, 0, 3, 7 },
+        { 384000, ACPU_PLL_1, 1, 1, 128000, 2, VDD_6, 128000, 0, 2, -1 },
+        { 528000, ACPU_PLL_2, 2, 1, 132000, 3, VDD_7, 128000, 0, 5, -1 },
+        { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
+};
+#endif
+
+static struct cpufreq_frequency_table freq_table[] = {
+        { 0, 122880 },
+        { 1, 128000 },
+        { 2, 245760 },
+        { 3, 384000 },
+        { 4, 528000 },
+        { 5, CPUFREQ_TABLE_END },
+};
+
+static int pc_pll_request(unsigned id, unsigned on)
+{
+        int res;
+        on = !!on;
+
+#if PERF_SWITCH_DEBUG
+        if (on)
+                printk(KERN_DEBUG "Enabling PLL %d\n", id);
+        else
+                printk(KERN_DEBUG "Disabling PLL %d\n", id);
+#endif
+
+        res = msm_proc_comm(PCOM_CLKCTL_RPC_PLL_REQUEST, &id, &on);
+        if (res < 0)
+                return res;
+
+#if PERF_SWITCH_DEBUG
+        if (on)
+                printk(KERN_DEBUG "PLL %d enabled\n", id);
+        else
+                printk(KERN_DEBUG "PLL %d disabled\n", id);
+#endif
+        return res;
+}
+
+
+/*----------------------------------------------------------------------------
+ * ARM11 'owned' clock control
+ *---------------------------------------------------------------------------*/
+
+unsigned long acpuclk_power_collapse(void) {
+        int ret = acpuclk_get_rate();
+        ret *= 1000;
+        if (ret > drv_state.power_collapse_khz)
+                acpuclk_set_rate(drv_state.power_collapse_khz, 1);
+        return ret;
+}
+
+unsigned long acpuclk_get_wfi_rate(void)
+{
+        return drv_state.wait_for_irq_khz;
+}
+
+unsigned long acpuclk_wait_for_irq(void) {
+        int ret = acpuclk_get_rate();
+        ret *= 1000;
+        if (ret > drv_state.wait_for_irq_khz)
+                acpuclk_set_rate(drv_state.wait_for_irq_khz, 1);
+        return ret;
+}
+
+static int acpuclk_set_vdd_level(int vdd)
+{
+        uint32_t current_vdd;
+
+        current_vdd = readl(A11S_VDD_SVS_PLEVEL_ADDR) & 0x07;
+
+#if PERF_SWITCH_DEBUG
+        printk(KERN_DEBUG "acpuclock: Switching VDD from %u -> %d\n",
+               current_vdd, vdd);
+#endif
+        writel((1 << 7) | (vdd << 3), A11S_VDD_SVS_PLEVEL_ADDR);
+        udelay(drv_state.vdd_switch_time_us);
+        if ((readl(A11S_VDD_SVS_PLEVEL_ADDR) & 0x7) != vdd) {
+#if PERF_SWITCH_DEBUG
+                printk(KERN_ERR "acpuclock: VDD set failed\n");
+#endif
+                return -EIO;
+        }
+
+#if PERF_SWITCH_DEBUG
+        printk(KERN_DEBUG "acpuclock: VDD switched\n");
+#endif
+        return 0;
+}
+
+/* Set proper dividers for the given clock speed. */
+static void acpuclk_set_div(const struct clkctl_acpu_speed *hunt_s) {
+        uint32_t reg_clkctl, reg_clksel, clk_div;
+
+        /* AHB_CLK_DIV */
+        clk_div = (readl(A11S_CLK_SEL_ADDR) >> 1) & 0x03;
+        /*
+         * If the new clock divider is higher than the previous, then
+         * program the divider before switching the clock
+         */
+        if (hunt_s->ahbclk_div > clk_div) {
+                reg_clksel = readl(A11S_CLK_SEL_ADDR);
+                reg_clksel &= ~(0x3 << 1);
+                reg_clksel |= (hunt_s->ahbclk_div << 1);
+                writel(reg_clksel, A11S_CLK_SEL_ADDR);
+        }
+        if ((readl(A11S_CLK_SEL_ADDR) & 0x01) == 0) {
+                /* SRC0 */
+
+                /* Program clock source */
+                reg_clkctl = readl(A11S_CLK_CNTL_ADDR);
+                reg_clkctl &= ~(0x07 << 4);
+                reg_clkctl |= (hunt_s->a11clk_src_sel << 4);
+                writel(reg_clkctl, A11S_CLK_CNTL_ADDR);
+
+                /* Program clock divider */
+                reg_clkctl = readl(A11S_CLK_CNTL_ADDR);
+                reg_clkctl &= ~0xf;
+                reg_clkctl |= hunt_s->a11clk_src_div;
+                writel(reg_clkctl, A11S_CLK_CNTL_ADDR);
+
+                /* Program clock source selection */
+                reg_clksel = readl(A11S_CLK_SEL_ADDR);
+                reg_clksel |= 1; /* CLK_SEL_SRC1NO  == SRC1 */
+                writel(reg_clksel, A11S_CLK_SEL_ADDR);
+        } else {
+                /* SRC1 */
+
+                /* Program clock source */
+                reg_clkctl = readl(A11S_CLK_CNTL_ADDR);
+                reg_clkctl &= ~(0x07 << 12);
+                reg_clkctl |= (hunt_s->a11clk_src_sel << 12);
+                writel(reg_clkctl, A11S_CLK_CNTL_ADDR);
+
+                /* Program clock divider */
+                reg_clkctl = readl(A11S_CLK_CNTL_ADDR);
+                reg_clkctl &= ~(0xf << 8);
+                reg_clkctl |= (hunt_s->a11clk_src_div << 8);
+                writel(reg_clkctl, A11S_CLK_CNTL_ADDR);
+
+                /* Program clock source selection */
+                reg_clksel = readl(A11S_CLK_SEL_ADDR);
+                reg_clksel &= ~1; /* CLK_SEL_SRC1NO  == SRC0 */
+                writel(reg_clksel, A11S_CLK_SEL_ADDR);
+        }
+
+        /*
+         * If the new clock divider is lower than the previous, then
+         * program the divider after switching the clock
+         */
+        if (hunt_s->ahbclk_div < clk_div) {
+                reg_clksel = readl(A11S_CLK_SEL_ADDR);
+                reg_clksel &= ~(0x3 << 1);
+                reg_clksel |= (hunt_s->ahbclk_div << 1);
+                writel(reg_clksel, A11S_CLK_SEL_ADDR);
+        }
+}
+
+int acpuclk_set_rate(unsigned long rate, int for_power_collapse)
+{
+        uint32_t reg_clkctl;
+        struct clkctl_acpu_speed *cur_s, *tgt_s, *strt_s;
+        int rc = 0;
+        unsigned int plls_enabled = 0, pll;
+
+        strt_s = cur_s = drv_state.current_speed;
+
+        WARN_ONCE(cur_s == NULL, "acpuclk_set_rate: not initialized\n");
+        if (cur_s == NULL)
+                return -ENOENT;
+
+        if (rate == (cur_s->a11clk_khz * 1000))
+                return 0;
+
+        for (tgt_s = acpu_freq_tbl; tgt_s->a11clk_khz != 0; tgt_s++) {
+                if (tgt_s->a11clk_khz == (rate / 1000))
+                        break;
+        }
+
+        if (tgt_s->a11clk_khz == 0)
+                return -EINVAL;
+
+        /* Choose the highest speed speed at or below 'rate' with same PLL. */
+        if (for_power_collapse && tgt_s->a11clk_khz < cur_s->a11clk_khz) {
+                while (tgt_s->pll != ACPU_PLL_TCXO && tgt_s->pll != cur_s->pll)
+                        tgt_s--;
+        }
+
+        if (strt_s->pll != ACPU_PLL_TCXO)
+                plls_enabled |= 1 << strt_s->pll;
+
+        if (!for_power_collapse) {
+                mutex_lock(&drv_state.lock);
+                if (strt_s->pll != tgt_s->pll && tgt_s->pll != ACPU_PLL_TCXO) {
+                        rc = pc_pll_request(tgt_s->pll, 1);
+                        if (rc < 0) {
+                                pr_err("PLL%d enable failed (%d)\n",
+                                        tgt_s->pll, rc);
+                                goto out;
+                        }
+                        plls_enabled |= 1 << tgt_s->pll;
+                }
+                /* Increase VDD if needed. */
+                if (tgt_s->vdd > cur_s->vdd) {
+                        if ((rc = acpuclk_set_vdd_level(tgt_s->vdd)) < 0) {
+                                printk(KERN_ERR "Unable to switch ACPU vdd\n");
+                                goto out;
+                        }
+                }
+        }
+
+        /* Set wait states for CPU inbetween frequency changes */
+        reg_clkctl = readl(A11S_CLK_CNTL_ADDR);
+        reg_clkctl |= (100 << 16); /* set WT_ST_CNT */
+        writel(reg_clkctl, A11S_CLK_CNTL_ADDR);
+
+#if PERF_SWITCH_DEBUG
+        printk(KERN_INFO "acpuclock: Switching from ACPU rate %u -> %u\n",
+               strt_s->a11clk_khz * 1000, tgt_s->a11clk_khz * 1000);
+#endif
+
+        while (cur_s != tgt_s) {
+                /*
+                 * Always jump to target freq if within 256mhz, regulardless of
+                 * PLL. If differnece is greater, use the predefinied
+                 * steppings in the table.
+                 */
+                int d = abs((int)(cur_s->a11clk_khz - tgt_s->a11clk_khz));
+                if (d > drv_state.max_speed_delta_khz) {
+                        /* Step up or down depending on target vs current. */
+                        int clk_index = tgt_s->a11clk_khz > cur_s->a11clk_khz ?
+                                cur_s->up : cur_s->down;
+                        if (clk_index < 0) { /* This should not happen. */
+                                printk(KERN_ERR "cur:%u target: %u\n",
+                                        cur_s->a11clk_khz, tgt_s->a11clk_khz);
+                                rc = -EINVAL;
+                                goto out;
+                        }
+                        cur_s = &acpu_freq_tbl[clk_index];
+                } else {
+                        cur_s = tgt_s;
+                }
+#if PERF_SWITCH_STEP_DEBUG
+                printk(KERN_DEBUG "%s: STEP khz = %u, pll = %d\n",
+                        __FUNCTION__, cur_s->a11clk_khz, cur_s->pll);
+#endif
+                if (!for_power_collapse&& cur_s->pll != ACPU_PLL_TCXO
+                    && !(plls_enabled & (1 << cur_s->pll))) {
+                        rc = pc_pll_request(cur_s->pll, 1);
+                        if (rc < 0) {
+                                pr_err("PLL%d enable failed (%d)\n",
+                                        cur_s->pll, rc);
+                                goto out;
+                        }
+                        plls_enabled |= 1 << cur_s->pll;
+                }
+
+                acpuclk_set_div(cur_s);
+                drv_state.current_speed = cur_s;
+                /* Re-adjust lpj for the new clock speed. */
+                loops_per_jiffy = cur_s->lpj;
+                udelay(drv_state.acpu_switch_time_us);
+        }
+
+        /* Nothing else to do for power collapse. */
+        if (for_power_collapse)
+                return 0;
+
+        /* Disable PLLs we are not using anymore. */
+        plls_enabled &= ~(1 << tgt_s->pll);
+        for (pll = ACPU_PLL_0; pll <= ACPU_PLL_2; pll++)
+                if (plls_enabled & (1 << pll)) {
+                        rc = pc_pll_request(pll, 0);
+                        if (rc < 0) {
+                                pr_err("PLL%d disable failed (%d)\n", pll, rc);
+                                goto out;
+                        }
+                }
+
+        /* Change the AXI bus frequency if we can. */
+        if (strt_s->axiclk_khz != tgt_s->axiclk_khz) {
+                rc = clk_set_rate(ebi1_clk, tgt_s->axiclk_khz * 1000);
+                if (rc < 0)
+                        pr_err("Setting AXI min rate failed!\n");
+        }
+
+        /* Drop VDD level if we can. */
+        if (tgt_s->vdd < strt_s->vdd) {
+                if (acpuclk_set_vdd_level(tgt_s->vdd) < 0)
+                        printk(KERN_ERR "acpuclock: Unable to drop ACPU vdd\n");
+        }
+
+#if PERF_SWITCH_DEBUG
+        printk(KERN_DEBUG "%s: ACPU speed change complete\n", __FUNCTION__);
+#endif
+out:
+        if (!for_power_collapse)
+                mutex_unlock(&drv_state.lock);
+        return rc;
+}
+
+static void __init acpuclk_init(void)
+{
+        struct clkctl_acpu_speed *speed;
+        uint32_t div, sel;
+        int rc;
+
+        /*
+         * Determine the rate of ACPU clock
+         */
+
+        if (!(readl(A11S_CLK_SEL_ADDR) & 0x01)) { /* CLK_SEL_SRC1N0 */
+                /* CLK_SRC0_SEL */
+                sel = (readl(A11S_CLK_CNTL_ADDR) >> 12) & 0x7;
+                /* CLK_SRC0_DIV */
+                div = (readl(A11S_CLK_CNTL_ADDR) >> 8) & 0x0f;
+        } else {
+                /* CLK_SRC1_SEL */
+                sel = (readl(A11S_CLK_CNTL_ADDR) >> 4) & 0x07;
+                /* CLK_SRC1_DIV */
+                div = readl(A11S_CLK_CNTL_ADDR) & 0x0f;
+        }
+
+        for (speed = acpu_freq_tbl; speed->a11clk_khz != 0; speed++) {
+                if (speed->a11clk_src_sel == sel
+                 && (speed->a11clk_src_div == div))
+                        break;
+        }
+        if (speed->a11clk_khz == 0) {
+                printk(KERN_WARNING "Warning - ACPU clock reports invalid speed\n");
+                return;
+        }
+
+        drv_state.current_speed = speed;
+
+        rc = clk_set_rate(ebi1_clk, speed->axiclk_khz * 1000);
+        if (rc < 0)
+                pr_err("Setting AXI min rate failed!\n");
+
+        printk(KERN_INFO "ACPU running at %d KHz\n", speed->a11clk_khz);
+}
+
+unsigned long acpuclk_get_rate(void)
+{
+        WARN_ONCE(drv_state.current_speed == NULL,
+                  "acpuclk_get_rate: not initialized\n");
+        if (drv_state.current_speed)
+                return drv_state.current_speed->a11clk_khz;
+        else
+                return 0;
+}
+
+uint32_t acpuclk_get_switch_time(void)
+{
+        return drv_state.acpu_switch_time_us;
+}
+
+/*----------------------------------------------------------------------------
+ * Clock driver initialization
+ *---------------------------------------------------------------------------*/
+
+/* Initalize the lpj field in the acpu_freq_tbl. */
+static void __init lpj_init(void)
+{
+        int i;
+        const struct clkctl_acpu_speed *base_clk = drv_state.current_speed;
+        for (i = 0; acpu_freq_tbl[i].a11clk_khz; i++) {
+                acpu_freq_tbl[i].lpj = cpufreq_scale(loops_per_jiffy,
+                                                base_clk->a11clk_khz,
+                                                acpu_freq_tbl[i].a11clk_khz);
+        }
+}
+
+void __init msm_acpu_clock_init(struct msm_acpu_clock_platform_data *clkdata)
+{
+        pr_info("acpu_clock_init()\n");
+
+        ebi1_clk = clk_get(NULL, "ebi1_clk");
+
+        mutex_init(&drv_state.lock);
+        drv_state.acpu_switch_time_us = clkdata->acpu_switch_time_us;
+        drv_state.max_speed_delta_khz = clkdata->max_speed_delta_khz;
+        drv_state.vdd_switch_time_us = clkdata->vdd_switch_time_us;
+        drv_state.power_collapse_khz = clkdata->power_collapse_khz;
+        drv_state.wait_for_irq_khz = clkdata->wait_for_irq_khz;
+        acpuclk_init();
+        lpj_init();
+#ifdef CONFIG_CPU_FREQ_TABLE
+        cpufreq_frequency_table_get_attr(freq_table, smp_processor_id());
+#endif
+}
diff --git a/arch/arm/mach-msm/acpuclock.h b/arch/arm/mach-msm/acpuclock.h
new file mode 100644
index 000000000000..415de2eb9a5e
--- /dev/null
+++ b/arch/arm/mach-msm/acpuclock.h
@@ -0,0 +1,32 @@
+/* arch/arm/mach-msm/acpuclock.h
+ *
+ * MSM architecture clock driver header
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (c) 2007 QUALCOMM Incorporated
+ * Author: San Mehat <san@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#ifndef __ARCH_ARM_MACH_MSM_ACPUCLOCK_H
+#define __ARCH_ARM_MACH_MSM_ACPUCLOCK_H
+
+int acpuclk_set_rate(unsigned long rate, int for_power_collapse);
+unsigned long acpuclk_get_rate(void);
+uint32_t acpuclk_get_switch_time(void);
+unsigned long acpuclk_wait_for_irq(void);
+unsigned long acpuclk_power_collapse(void);
+unsigned long acpuclk_get_wfi_rate(void);
+
+
+#endif
+
diff --git a/arch/arm/mach-msm/include/mach/board.h b/arch/arm/mach-msm/include/mach/board.h
index 264d62e519f3..fb12fd87bb81 100644
--- a/arch/arm/mach-msm/include/mach/board.h
+++ b/arch/arm/mach-msm/include/mach/board.h
@@ -27,6 +27,16 @@ struct msm_mddi_platform_data
         unsigned has_vsync_irq:1;
 };
 
+struct msm_acpu_clock_platform_data
+{
+        uint32_t acpu_switch_time_us;
+        uint32_t max_speed_delta_khz;
+        uint32_t vdd_switch_time_us;
+        unsigned long power_collapse_khz;
+        unsigned long wait_for_irq_khz;
+};
+
+  
 /* common init routines for use by arch/arm/mach-msm/board-*.c */
 
 void __init msm_add_devices(void);
@@ -34,5 +44,6 @@ void __init msm_map_common_io(void);
 void __init msm_init_irq(void);
 void __init msm_init_gpio(void);
 void __init msm_clock_init(void);
+void __init msm_acpu_clock_init(struct msm_acpu_clock_platform_data *);
 
 #endif