[PATCHv3] cpufreq for freescale mx51
Yong Shen
yong.shen at linaro.org
Tue Oct 19 05:38:01 EDT 2010
Vishwanath,
Thanks for suggestion.
Voltage change is not a must for frequency change, and it can be integrate
in after regulator driver is ready for mx51.
Yong
On Tue, Oct 19, 2010 at 5:18 PM, Vishwanath Sripathy <
vishwanath.sripathy at linaro.org> wrote:
> Yong,
>
> >On Mon, Oct 18, 2010 at 1:51 PM, <yong.shen at linaro.org> wrote:
> >From: Yong Shen <yong.shen at linaro.org>
>
> >the operating points are tested on babbage 3.0
> Commit log needs more description like
> What are the supported operating points,
> Is there any link between mpu OPP and other devices?
> What are the platforms this patch is tested against
> which codebase/tree this patch is based upon
> >
> >Signed-off-by: Yong Shen <yong.shen at 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 | 22 +++-
> > arch/arm/mach-mx5/cpu.c | 2 +
> > 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 | 202
> ++++++++++++++++++++++++++++++++
> > arch/arm/plat-mxc/include/mach/mxc.h | 20 +++-
> > 11 files changed, 306 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 e4ea9cb..d9ad605 100644
> >--- a/arch/arm/Kconfig
> >+++ b/arch/arm/Kconfig
> >@@ -1692,6 +1692,12 @@ 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..2fadac5 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 6e384d9..74c796f 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 at 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_op-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_op = mx51_get_cpu_op;
> >+#endif
> >+}
> >+
> > MACHINE_START(MX51_BABBAGE, "Freescale MX51 Babbage Board")
> > /* Maintainer: Amit Kucheria <amit.kucheria at 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..f89d8a0 100644
> >--- a/arch/arm/mach-mx5/clock-mx51.c
> >+++ b/arch/arm/mach-mx5/clock-mx51.c
> >@@ -330,7 +330,7 @@ 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;
> >@@ -342,6 +342,22 @@ 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;
> >@@ -693,7 +709,8 @@ 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 = {
> >@@ -837,6 +854,7 @@ 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..f3fe51a 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_op *(*get_cpu_op)(int *op);
> >+
> > 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_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 78d405e..a833d38 100644
> >--- a/arch/arm/plat-mxc/Makefile
> >+++ b/arch/arm/plat-mxc/Makefile
> >@@ -16,6 +16,7 @@ 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
> >+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..9cabeb9
> >--- /dev/null
> >+++ b/arch/arm/plat-mxc/cpufreq.c
> >@@ -0,0 +1,202 @@
> >+/*
> >+ * 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)
> >+
> >+static int cpu_freq_khz_min;
> >+static int cpu_freq_khz_max;
> >+static int arm_normal_clk;
> >+
> >+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;
>
> Is it not needed to scale voltage also along with frequency?
>
> >+
> >+ 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);
> >+ }
> >+
> >+ 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) {
> >+ clk_put(cpu_clk);
> >+ return -ENOMEM;
> >+ }
> >+
> >+ 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;
> >+
> >+ arm_normal_clk = cpu_freq_khz_max * 1000;
> >+
> >+ /* Manual states, that PLL stabilizes in two CLK32 periods */
> >+ policy->cpuinfo.transition_latency = 2 / CLK32_FREQ * NANOSECOND;
> >+
> >+ 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__);
> >+ 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);
> >+
> >+ set_cpu_freq(arm_normal_clk);
> >+ 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 at 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..888dddc 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 at 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_op {
> >+ 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_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))
> >--
> >1.6.3.3
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20101019/8f9d4b79/attachment-0001.html>
More information about the linux-arm-kernel
mailing list