From: Yong Shen yong.shen@linaro.org

Currently, only two operating points: 160Mhz and 800Mhz. the operating points are tested on babbage 3.0

Signed-off-by: Yong Shen yong.shen@linaro.org --- arch/arm/Kconfig | 6 + arch/arm/mach-mx5/Kconfig | 1 + arch/arm/mach-mx5/Makefile | 1 + arch/arm/mach-mx5/board-mx51_babbage.c | 6 +- arch/arm/mach-mx5/clock-mx51.c | 22 +++- arch/arm/mach-mx5/cpu_op-mx51.c | 29 +++++ arch/arm/mach-mx5/cpu_op-mx51.h | 14 ++ arch/arm/plat-mxc/Makefile | 1 + arch/arm/plat-mxc/cpufreq.c | 206 ++++++++++++++++++++++++++++++++ arch/arm/plat-mxc/include/mach/mxc.h | 13 ++- 10 files changed, 295 insertions(+), 4 deletions(-) create mode 100644 arch/arm/mach-mx5/cpu_op-mx51.c create mode 100644 arch/arm/mach-mx5/cpu_op-mx51.h create mode 100644 arch/arm/plat-mxc/cpufreq.c

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 553b7cf..12115ff 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1584,6 +1584,12 @@ if ARCH_HAS_CPUFREQ

source "drivers/cpufreq/Kconfig"

+config CPU_FREQ_IMX + tristate "CPUfreq driver for i.MX CPUs" + depends on ARCH_MXC && CPU_FREQ + help + This enables the CPUfreq driver for i.MX CPUs. + config CPU_FREQ_SA1100 bool

diff --git a/arch/arm/mach-mx5/Kconfig b/arch/arm/mach-mx5/Kconfig index a2df9ac..427a66c 100644 --- a/arch/arm/mach-mx5/Kconfig +++ b/arch/arm/mach-mx5/Kconfig @@ -6,6 +6,7 @@ config ARCH_MX51 select MXC_TZIC select ARCH_MXC_IOMUX_V3 select ARCH_MXC_AUDMUX_V2 + select ARCH_HAS_CPUFREQ

comment "MX5 platforms:"

diff --git a/arch/arm/mach-mx5/Makefile b/arch/arm/mach-mx5/Makefile index 1769c16..462f177 100644 --- a/arch/arm/mach-mx5/Makefile +++ b/arch/arm/mach-mx5/Makefile @@ -5,6 +5,7 @@ # Object file lists. obj-y := cpu.o mm.o clock-mx51.o devices.o

+obj-$(CONFIG_CPU_FREQ_IMX) += cpu_op-mx51.o obj-$(CONFIG_MACH_MX51_BABBAGE) += board-mx51_babbage.o obj-$(CONFIG_MACH_MX51_3DS) += board-mx51_3ds.o obj-$(CONFIG_MACH_EUKREA_CPUIMX51) += board-cpuimx51.o diff --git a/arch/arm/mach-mx5/board-mx51_babbage.c b/arch/arm/mach-mx5/board-mx51_babbage.c index 23ee4a4..26b8e14 100644 --- a/arch/arm/mach-mx5/board-mx51_babbage.c +++ b/arch/arm/mach-mx5/board-mx51_babbage.c @@ -1,5 +1,5 @@ /* - * Copyright 2009 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved. * Copyright (C) 2009-2010 Amit Kucheria amit.kucheria@canonical.com * * The code contained herein is licensed under the GNU General Public @@ -32,6 +32,7 @@

#include "devices-imx51.h" #include "devices.h" +#include "cpu_op-mx51.h"

#define BABBAGE_USB_HUB_RESET (0*32 + 7) /* GPIO_1_7 */ #define BABBAGE_USBH1_STP (0*32 + 27) /* GPIO_1_27 */ @@ -282,6 +283,9 @@ static void __init mxc_board_init(void) { struct pad_desc usbh1stp = MX51_PAD_USBH1_STP__USBH1_STP;

+#if defined(CONFIG_CPU_FREQ_IMX) + get_cpu_op = mx51_get_cpu_op; +#endif mxc_iomux_v3_setup_multiple_pads(mx51babbage_pads, ARRAY_SIZE(mx51babbage_pads)); mxc_init_imx_uart(); diff --git a/arch/arm/mach-mx5/clock-mx51.c b/arch/arm/mach-mx5/clock-mx51.c index f2aae92..8ac36d8 100644 --- a/arch/arm/mach-mx5/clock-mx51.c +++ b/arch/arm/mach-mx5/clock-mx51.c @@ -362,7 +362,7 @@ static int _clk_lp_apm_set_parent(struct clk *clk, struct clk *parent) return 0; }

-static unsigned long clk_arm_get_rate(struct clk *clk) +static unsigned long clk_cpu_get_rate(struct clk *clk) { u32 cacrr, div; unsigned long parent_rate; @@ -374,6 +374,22 @@ static unsigned long clk_arm_get_rate(struct clk *clk) return parent_rate / div; }

+static int clk_cpu_set_rate(struct clk *clk, unsigned long rate) +{ + u32 reg, cpu_podf; + unsigned long parent_rate; + + parent_rate = clk_get_rate(clk->parent); + cpu_podf = parent_rate / rate - 1; + /* use post divider to change freq */ + reg = __raw_readl(MXC_CCM_CACRR); + reg &= ~MXC_CCM_CACRR_ARM_PODF_MASK; + reg |= cpu_podf << MXC_CCM_CACRR_ARM_PODF_OFFSET; + __raw_writel(reg, MXC_CCM_CACRR); + + return 0; +} + static int _clk_periph_apm_set_parent(struct clk *clk, struct clk *parent) { u32 reg, mux; @@ -736,7 +752,8 @@ static struct clk periph_apm_clk = {

static struct clk cpu_clk = { .parent = &pll1_sw_clk, - .get_rate = clk_arm_get_rate, + .get_rate = clk_cpu_get_rate, + .set_rate = clk_cpu_set_rate, };

static struct clk ahb_clk = { @@ -1064,6 +1081,7 @@ static struct clk_lookup lookups[] = { _REGISTER_CLOCK("imx51-cspi.0", NULL, cspi_clk) _REGISTER_CLOCK("sdhci-esdhc-imx.0", NULL, esdhc1_clk) _REGISTER_CLOCK("sdhci-esdhc-imx.1", NULL, esdhc2_clk) + _REGISTER_CLOCK(NULL, "cpu_clk", cpu_clk) };

static void clk_tree_init(void) diff --git a/arch/arm/mach-mx5/cpu_op-mx51.c b/arch/arm/mach-mx5/cpu_op-mx51.c new file mode 100644 index 0000000..9d34c3d --- /dev/null +++ b/arch/arm/mach-mx5/cpu_op-mx51.c @@ -0,0 +1,29 @@ +/* + * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include <linux/types.h> +#include <mach/hardware.h> +#include <linux/kernel.h> + +static struct cpu_op mx51_cpu_op[] = { + { + .cpu_rate = 160000000,}, + { + .cpu_rate = 800000000,}, +}; + +struct cpu_op *mx51_get_cpu_op(int *op) +{ + *op = ARRAY_SIZE(mx51_cpu_op); + return mx51_cpu_op; +} diff --git a/arch/arm/mach-mx5/cpu_op-mx51.h b/arch/arm/mach-mx5/cpu_op-mx51.h new file mode 100644 index 0000000..97477fe --- /dev/null +++ b/arch/arm/mach-mx5/cpu_op-mx51.h @@ -0,0 +1,14 @@ +/* + * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +extern struct cpu_op *mx51_get_cpu_op(int *op); diff --git a/arch/arm/plat-mxc/Makefile b/arch/arm/plat-mxc/Makefile index 06875b4..3726709 100644 --- a/arch/arm/plat-mxc/Makefile +++ b/arch/arm/plat-mxc/Makefile @@ -18,6 +18,7 @@ obj-$(CONFIG_MXC_USE_EPIT) += epit.o obj-$(CONFIG_ARCH_MXC_AUDMUX_V1) += audmux-v1.o obj-$(CONFIG_ARCH_MXC_AUDMUX_V2) += audmux-v2.o obj-$(CONFIG_MXC_DEBUG_BOARD) += 3ds_debugboard.o +obj-$(CONFIG_CPU_FREQ_IMX) += cpufreq.o ifdef CONFIG_SND_IMX_SOC obj-y += ssi-fiq.o obj-y += ssi-fiq-ksym.o diff --git a/arch/arm/plat-mxc/cpufreq.c b/arch/arm/plat-mxc/cpufreq.c new file mode 100644 index 0000000..039538e --- /dev/null +++ b/arch/arm/plat-mxc/cpufreq.c @@ -0,0 +1,206 @@ +/* + * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/* + * A driver for the Freescale Semiconductor i.MXC CPUfreq module. + * The CPUFREQ driver is for controling CPU frequency. It allows you to change + * the CPU clock speed on the fly. + */ + +#include <linux/cpufreq.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <mach/hardware.h> +#include <mach/clock.h> + +#define CLK32_FREQ 32768 +#define NANOSECOND (1000 * 1000 * 1000) + +struct cpu_op *(*get_cpu_op)(int *op); + +static int cpu_freq_khz_min; +static int cpu_freq_khz_max; + +static struct clk *cpu_clk; +static struct cpufreq_frequency_table *imx_freq_table; + +static int cpu_op_nr; +static struct cpu_op *cpu_op_tbl; + +static int set_cpu_freq(int freq) +{ + int ret = 0; + int org_cpu_rate; + + org_cpu_rate = clk_get_rate(cpu_clk); + if (org_cpu_rate == freq) + return ret; + + ret = clk_set_rate(cpu_clk, freq); + if (ret != 0) { + printk(KERN_DEBUG "cannot set CPU clock rate\n"); + return ret; + } + + return ret; +} + +static int mxc_verify_speed(struct cpufreq_policy *policy) +{ + if (policy->cpu != 0) + return -EINVAL; + + return cpufreq_frequency_table_verify(policy, imx_freq_table); +} + +static unsigned int mxc_get_speed(unsigned int cpu) +{ + if (cpu) + return 0; + + return clk_get_rate(cpu_clk) / 1000; +} + +static int mxc_set_target(struct cpufreq_policy *policy, + unsigned int target_freq, unsigned int relation) +{ + struct cpufreq_freqs freqs; + int freq_Hz; + int ret = 0; + unsigned int index; + + cpufreq_frequency_table_target(policy, imx_freq_table, + target_freq, relation, &index); + freq_Hz = imx_freq_table[index].frequency * 1000; + + freqs.old = clk_get_rate(cpu_clk) / 1000; + freqs.new = freq_Hz / 1000; + freqs.cpu = 0; + freqs.flags = 0; + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); + + ret = set_cpu_freq(freq_Hz); + + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); + + return ret; +} + +static int __init mxc_cpufreq_init(struct cpufreq_policy *policy) +{ + int ret; + int i; + + printk(KERN_INFO "i.MXC CPU frequency driver\n"); + + if (policy->cpu != 0) + return -EINVAL; + + if (!get_cpu_op) + return -EINVAL; + + cpu_clk = clk_get(NULL, "cpu_clk"); + if (IS_ERR(cpu_clk)) { + printk(KERN_ERR "%s: failed to get cpu clock\n", __func__); + return PTR_ERR(cpu_clk); + } + + cpu_op_tbl = get_cpu_op(&cpu_op_nr); + + cpu_freq_khz_min = cpu_op_tbl[0].cpu_rate / 1000; + cpu_freq_khz_max = cpu_op_tbl[0].cpu_rate / 1000; + + imx_freq_table = kmalloc( + sizeof(struct cpufreq_frequency_table) * (cpu_op_nr + 1), + GFP_KERNEL); + if (!imx_freq_table) { + ret = -ENOMEM; + goto err1; + } + + for (i = 0; i < cpu_op_nr; i++) { + imx_freq_table[i].index = i; + imx_freq_table[i].frequency = cpu_op_tbl[i].cpu_rate / 1000; + + if ((cpu_op_tbl[i].cpu_rate / 1000) < cpu_freq_khz_min) + cpu_freq_khz_min = cpu_op_tbl[i].cpu_rate / 1000; + + if ((cpu_op_tbl[i].cpu_rate / 1000) > cpu_freq_khz_max) + cpu_freq_khz_max = cpu_op_tbl[i].cpu_rate / 1000; + } + + imx_freq_table[i].index = i; + imx_freq_table[i].frequency = CPUFREQ_TABLE_END; + + policy->cur = clk_get_rate(cpu_clk) / 1000; + policy->governor = CPUFREQ_DEFAULT_GOVERNOR; + policy->min = policy->cpuinfo.min_freq = cpu_freq_khz_min; + policy->max = policy->cpuinfo.max_freq = cpu_freq_khz_max; + + /* Manual states, that PLL stabilizes in two CLK32 periods */ + policy->cpuinfo.transition_latency = 2 * NANOSECOND / CLK32_FREQ; + + ret = cpufreq_frequency_table_cpuinfo(policy, imx_freq_table); + + if (ret < 0) { + printk(KERN_ERR "%s: failed to register i.MXC CPUfreq \ + with error code %d\n", __func__, ret); + goto err; + } + + cpufreq_frequency_table_get_attr(imx_freq_table, policy->cpu); + return 0; +err: + kfree(imx_freq_table); +err1: + clk_put(cpu_clk); + return ret; +} + +static int mxc_cpufreq_exit(struct cpufreq_policy *policy) +{ + cpufreq_frequency_table_put_attr(policy->cpu); + + set_cpu_freq(cpu_freq_khz_max * 1000); + clk_put(cpu_clk); + kfree(imx_freq_table); + return 0; +} + +static struct cpufreq_driver mxc_driver = { + .flags = CPUFREQ_STICKY, + .verify = mxc_verify_speed, + .target = mxc_set_target, + .get = mxc_get_speed, + .init = mxc_cpufreq_init, + .exit = mxc_cpufreq_exit, + .name = "imx", +}; + +static int __devinit mxc_cpufreq_driver_init(void) +{ + return cpufreq_register_driver(&mxc_driver); +} + +static void mxc_cpufreq_driver_exit(void) +{ + cpufreq_unregister_driver(&mxc_driver); +} + +module_init(mxc_cpufreq_driver_init); +module_exit(mxc_cpufreq_driver_exit); + +MODULE_AUTHOR("Freescale Semiconductor Inc. Yong Shen yong.shen@linaro.org"); +MODULE_DESCRIPTION("CPUfreq driver for i.MX"); +MODULE_LICENSE("GPL"); diff --git a/arch/arm/plat-mxc/include/mach/mxc.h b/arch/arm/plat-mxc/include/mach/mxc.h index a790bf2..a42c720 100644 --- a/arch/arm/plat-mxc/include/mach/mxc.h +++ b/arch/arm/plat-mxc/include/mach/mxc.h @@ -1,5 +1,5 @@ /* - * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved. + * Copyright 2004-2007, 2010 Freescale Semiconductor, Inc. All Rights Reserved. * Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de) * * This program is free software; you can redistribute it and/or @@ -20,6 +20,8 @@ #ifndef __ASM_ARCH_MXC_H__ #define __ASM_ARCH_MXC_H__

+#include <linux/types.h> + #ifndef __ASM_ARCH_MXC_HARDWARE_H__ #error "Do not include directly." #endif @@ -133,6 +135,15 @@ extern unsigned int __mxc_cpu_type; # define cpu_is_mxc91231() (0) #endif

+#ifndef __ASSEMBLY__ + +struct cpu_op { + u32 cpu_rate; +}; + +extern struct cpu_op *(*get_cpu_op)(int *op); +#endif + #if defined(CONFIG_ARCH_MX3) || defined(CONFIG_ARCH_MX2) /* These are deprecated, use mx[23][157]_setup_weimcs instead. */ #define CSCR_U(n) (IO_ADDRESS(WEIM_BASE_ADDR + n * 0x10))