On Fri, Oct 08, 2010 at 04:08:27PM +0800, yong.s...@linaro.org wrote: > From: Yong Shen <yong.s...@linaro.org> > > it is tested on babbage 3.0 > > Signed-off-by: Yong Shen <yong.s...@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 | 12 ++- > arch/arm/mach-mx5/clock-mx51.c | 24 ++++ > arch/arm/mach-mx5/cpu.c | 2 + > arch/arm/mach-mx5/cpu_wp-mx51.c | 42 ++++++ > arch/arm/mach-mx5/cpu_wp-mx51.h | 14 ++ > arch/arm/plat-mxc/Makefile | 2 + > arch/arm/plat-mxc/cpufreq.c | 236 > ++++++++++++++++++++++++++++++++ > arch/arm/plat-mxc/include/mach/mxc.h | 20 +++- > 11 files changed, 358 insertions(+), 2 deletions(-) > create mode 100644 arch/arm/mach-mx5/cpu_wp-mx51.c > create mode 100644 arch/arm/mach-mx5/cpu_wp-mx51.h > create mode 100644 arch/arm/plat-mxc/cpufreq.c > > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig > index d203b84..71a572a 100644 > --- a/arch/arm/Kconfig > +++ b/arch/arm/Kconfig > @@ -1690,6 +1690,12 @@ 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 0848db5..7a621b4 100644 > --- a/arch/arm/mach-mx5/Kconfig > +++ b/arch/arm/mach-mx5/Kconfig > @@ -5,6 +5,7 @@ config ARCH_MX51 > default y > select MXC_TZIC > select ARCH_MXC_IOMUX_V3 > + select ARCH_HAS_CPUFREQ > > comment "MX5 platforms:" > > diff --git a/arch/arm/mach-mx5/Makefile b/arch/arm/mach-mx5/Makefile > index 86c66e7..e2af3fb 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-$(CONFIG_CPU_FREQ_IMX) += cpu_wp-mx51.o > obj-$(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 6e384d9..2d2a052 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.kuche...@canonical.com> > * > * The code contained herein is licensed under the GNU General Public > @@ -32,6 +32,7 @@ > #include <asm/mach/time.h> > > #include "devices.h" > +#include "cpu_wp-mx51.h" > > #define BABBAGE_USB_HUB_RESET (0*32 + 7) /* GPIO_1_7 */ > #define BABBAGE_USBH1_STP (0*32 + 27) /* GPIO_1_27 */ > @@ -279,8 +280,17 @@ static struct sys_timer mxc_timer = { > .init = mx51_babbage_timer_init, > }; > > +static void __init fixup_mxc_board(struct machine_desc *desc, struct tag > *tags, > + char **cmdline, struct meminfo *mi) > +{ > +#if defined(CONFIG_CPU_FREQ_IMX) > + get_cpu_wp = mx51_get_cpu_wp; > +#endif > +} > + > MACHINE_START(MX51_BABBAGE, "Freescale MX51 Babbage Board") > /* Maintainer: Amit Kucheria <amit.kuche...@canonical.com> */ > + .fixup = fixup_mxc_board, > .phys_io = MX51_AIPS1_BASE_ADDR, > .io_pg_offst = ((MX51_AIPS1_BASE_ADDR_VIRT) >> 18) & 0xfffc, > .boot_params = PHYS_OFFSET + 0x100, > diff --git a/arch/arm/mach-mx5/clock-mx51.c b/arch/arm/mach-mx5/clock-mx51.c > index 6af69de..f23cfab 100644 > --- a/arch/arm/mach-mx5/clock-mx51.c > +++ b/arch/arm/mach-mx5/clock-mx51.c > @@ -39,6 +39,8 @@ static struct clk ahb_clk; > static struct clk ipg_clk; > static struct clk usboh3_clk; > > +DEFINE_SPINLOCK(clk_lock);
static, if needed at all. > + > #define MAX_DPLL_WAIT_TRIES 1000 /* 1000 * udelay(1) = 1ms */ > > static int _clk_ccgr_enable(struct clk *clk) > @@ -342,6 +344,26 @@ 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 flags, parent_rate; > + > + parent_rate = clk_get_rate(clk->parent); > + cpu_podf = parent_rate / rate - 1; > + /* use post divider to change freq */ > + spin_lock_irqsave(&clk_lock, flags); > + > + 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); > + > + spin_unlock_irqrestore(&clk_lock, flags); Why this spinlock? The whole clock code is protected by a mutex already. > + > + return 0; > +} > + > static int _clk_periph_apm_set_parent(struct clk *clk, struct clk *parent) > { > u32 reg, mux; > @@ -694,6 +716,7 @@ static struct clk periph_apm_clk = { > static struct clk cpu_clk = { > .parent = &pll1_sw_clk, > .get_rate = clk_arm_get_rate, > + .set_rate = _clk_cpu_set_rate, The names should be consistent. Either clk_arm_[sg]et_rate or clk_cpu. ALso, please remove those leading underscores. > }; > > static struct clk ahb_clk = { > @@ -837,6 +860,7 @@ static struct clk_lookup lookups[] = { > _REGISTER_CLOCK("fsl-usb2-udc", "usb", usboh3_clk) > _REGISTER_CLOCK("fsl-usb2-udc", "usb_ahb", ahb_clk) > _REGISTER_CLOCK("imx-keypad.0", NULL, kpp_clk) > + _REGISTER_CLOCK(NULL, "cpu_clk", cpu_clk) > }; > > static void clk_tree_init(void) > diff --git a/arch/arm/mach-mx5/cpu.c b/arch/arm/mach-mx5/cpu.c > index 2d37785..83add9c 100644 > --- a/arch/arm/mach-mx5/cpu.c > +++ b/arch/arm/mach-mx5/cpu.c > @@ -22,6 +22,8 @@ static int cpu_silicon_rev = -1; > > #define SI_REV 0x48 > > +struct cpu_wp *(*get_cpu_wp)(int *wp); > + This is not needed. > static void query_silicon_parameter(void) > { > void __iomem *rom = ioremap(MX51_IROM_BASE_ADDR, MX51_IROM_SIZE); > diff --git a/arch/arm/mach-mx5/cpu_wp-mx51.c b/arch/arm/mach-mx5/cpu_wp-mx51.c > new file mode 100644 > index 0000000..51bde45 > --- /dev/null > +++ b/arch/arm/mach-mx5/cpu_wp-mx51.c > @@ -0,0 +1,42 @@ > +/* > + * 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> > + > +static struct cpu_wp cpu_wp_auto[] = { > + { > + .pll_rate = 800000000, > + .cpu_rate = 160000000, > + .pdf = 4, > + .mfi = 8, > + .mfd = 2, > + .mfn = 1, > + .cpu_podf = 4, > + .cpu_voltage = 850000,}, > + { > + .pll_rate = 800000000, > + .cpu_rate = 800000000, > + .pdf = 0, > + .mfi = 8, > + .mfd = 2, > + .mfn = 1, > + .cpu_podf = 0, > + .cpu_voltage = 1100000,}, > +}; > + > +struct cpu_wp *mx51_get_cpu_wp(int *wp) > +{ > + *wp = sizeof(cpu_wp_auto) / sizeof(struct cpu_wp); use ARRAY_SIZE here. > + return cpu_wp_auto; > +} > diff --git a/arch/arm/mach-mx5/cpu_wp-mx51.h b/arch/arm/mach-mx5/cpu_wp-mx51.h > new file mode 100644 > index 0000000..8038b62 > --- /dev/null > +++ b/arch/arm/mach-mx5/cpu_wp-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_wp *mx51_get_cpu_wp(int *wp); > diff --git a/arch/arm/plat-mxc/Makefile b/arch/arm/plat-mxc/Makefile > index 78d405e..0b8464f 100644 > --- a/arch/arm/plat-mxc/Makefile > +++ b/arch/arm/plat-mxc/Makefile > @@ -16,6 +16,8 @@ obj-$(CONFIG_MXC_ULPI) += ulpi.o > obj-$(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 > +# CPU FREQ support > +obj-$(CONFIG_CPU_FREQ_IMX) += cpufreq.o I think most people digging in kernel code get that without the comment. > 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..9990ea8 > --- /dev/null > +++ b/arch/arm/plat-mxc/cpufreq.c > @@ -0,0 +1,236 @@ > +/* > + * 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/types.h> > +#include <linux/kernel.h> > +#include <linux/cpufreq.h> > +#include <linux/init.h> > +#include <linux/proc_fs.h> > +#include <linux/regulator/consumer.h> > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/io.h> > +#include <mach/hardware.h> > +#include <asm/setup.h> > +#include <mach/clock.h> > +#include <asm/cacheflush.h> > +#include <linux/hrtimer.h> Please clean up the includes. At least linux/proc_fs.h, linux/regulator/consumer.h, asm/cacheflush.h and linux/hrtimer.h are unused. > + > +static int cpu_freq_khz_min; > +static int cpu_freq_khz_max; > +static int arm_lpm_clk; > +static int arm_normal_clk; > +static int cpufreq_suspended; > + > +static struct clk *cpu_clk; > +static struct cpufreq_frequency_table *imx_freq_table; > + > +static int cpu_wp_nr; > +static struct cpu_wp *cpu_wp_tbl; > + > +static int set_cpu_freq(int freq) > +{ > + int ret = 0; > + int org_cpu_rate; > + int gp_volt = 0; > + int i; > + > + org_cpu_rate = clk_get_rate(cpu_clk); > + if (org_cpu_rate == freq) > + return ret; > + > + for (i = 0; i < cpu_wp_nr; i++) { > + if (freq == cpu_wp_tbl[i].cpu_rate) > + gp_volt = cpu_wp_tbl[i].cpu_voltage; > + } > + > + if (gp_volt == 0) > + return ret; I can't see why we need this check here. This can only happen when the table is not correctly initialized. Furthermore, cpu voltages are not handled yet. I'm sure we'll find a better place for this check once we start supporting voltage changes, so I think you can remove it here. > + > + 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; > + > + if (cpufreq_suspended) { cpufreq_suspended is never set in this code, so please remove this until we get a user for this. > + target_freq = clk_get_rate(cpu_clk) / 1000; > + cpufreq_frequency_table_target(policy, imx_freq_table, > + target_freq, relation, &index); > + freq_Hz = imx_freq_table[index].frequency * 1000; > + > + if (freq_Hz == arm_lpm_clk) > + freqs.old = cpu_wp_tbl[cpu_wp_nr - 2].cpu_rate / 1000; > + else > + freqs.old = arm_lpm_clk / 1000; > + > + freqs.new = freq_Hz / 1000; > + freqs.cpu = 0; > + freqs.flags = 0; > + cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE); > + cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE); > + return ret; > + } > + > + 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); > + > + if (freqs.old != freqs.new) > + 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; > + > + 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); > + } > + > + /* Set the current working point. */ > + cpu_wp_tbl = get_cpu_wp(&cpu_wp_nr); The comment seems to have nothing to do with what the code does. You don't set a workpoint here but get the table of available workpoints. > + > + cpu_freq_khz_min = cpu_wp_tbl[0].cpu_rate / 1000; > + cpu_freq_khz_max = cpu_wp_tbl[0].cpu_rate / 1000; > + > + imx_freq_table = kmalloc( > + sizeof(struct cpufreq_frequency_table) * (cpu_wp_nr + 1), > + GFP_KERNEL); kmalloc can fail. > + > + for (i = 0; i < cpu_wp_nr; i++) { > + imx_freq_table[i].index = i; > + imx_freq_table[i].frequency = > + cpu_wp_tbl[i].cpu_rate / 1000; > + > + if ((cpu_wp_tbl[i].cpu_rate / 1000) < cpu_freq_khz_min) > + cpu_freq_khz_min = cpu_wp_tbl[i].cpu_rate / 1000; > + > + if ((cpu_wp_tbl[i].cpu_rate / 1000) > cpu_freq_khz_max) > + cpu_freq_khz_max = cpu_wp_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; > + > + arm_lpm_clk = cpu_freq_khz_min * 1000; > + arm_normal_clk = cpu_freq_khz_max * 1000; > + > + /* Manual states, that PLL stabilizes in two CLK32 periods */ > + policy->cpuinfo.transition_latency = 10; transition_latency is in nano seconds, the correct value here is 2/32768*1000*1000*1000 = 61035. > + > + ret = cpufreq_frequency_table_cpuinfo(policy, imx_freq_table); > + > + if (ret < 0) { > + clk_put(cpu_clk); > + printk(KERN_ERR "%s: failed to register i.MXC CPUfreq\n", > + __func__); It's always good to print the error code with such messages. > + return ret; > + } > + > + cpufreq_frequency_table_get_attr(imx_freq_table, policy->cpu); > + return 0; > +} > + > +static int mxc_cpufreq_exit(struct cpufreq_policy *policy) > +{ > + cpufreq_frequency_table_put_attr(policy->cpu); > + > + /* Reset CPU to 665MHz */ > + set_cpu_freq(arm_normal_clk); arm_normal_clk is initialized to cpu_freq_khz_max * 1000 and never touched again. It would be clearer here to remove arm_normal_clk and write cpu_freq_khz_max * 1000 directly here. Then you can also remove the comment which is wrong for most i.MXs, even for the i.MX51. Also, you forget to kfree the resources alloced above. > + clk_put(cpu_clk); > + 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.s...@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..31df991 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 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved. > * Copyright (C) 2008 Juergen Beisert (ker...@pengutronix.de) > * > * This program is free software; you can redistribute it and/or > @@ -133,6 +133,24 @@ extern unsigned int __mxc_cpu_type; > # define cpu_is_mxc91231() (0) > #endif > > +#ifndef __ASSEMBLY__ > + > +struct cpu_wp { > + u32 pll_reg; > + u32 pll_rate; > + u32 cpu_rate; > + u32 pdr0_reg; > + u32 pdf; > + u32 mfi; > + u32 mfd; > + u32 mfn; > + u32 cpu_voltage; > + u32 cpu_podf; > +}; > + > +extern struct cpu_wp *(*get_cpu_wp)(int *wp); > +#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)) > -- > 1.6.3.3 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-ker...@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ linaro-dev mailing list linaro-dev@lists.linaro.org http://lists.linaro.org/mailman/listinfo/linaro-dev