+++ /dev/null
-From 083183f7770ae4fb6f23c99a64a3c5058b9b3b40 Mon Sep 17 00:00:00 2001
-From: popcornmix <popcornmix@gmail.com>
-Date: Sat, 2 Nov 2013 22:44:41 +0000
-Subject: [PATCH 031/196] Add cpufreq driver
-
----
- arch/arm/Kconfig | 1 +
- drivers/cpufreq/Kconfig.arm | 8 ++
- drivers/cpufreq/Makefile | 1 +
- drivers/cpufreq/bcm2835-cpufreq.c | 239 ++++++++++++++++++++++++++++++++++++++
- 4 files changed, 249 insertions(+)
- create mode 100755 drivers/cpufreq/bcm2835-cpufreq.c
-
-diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
-index 5468f1f..4e36ccd 100644
---- a/arch/arm/Kconfig
-+++ b/arch/arm/Kconfig
-@@ -369,6 +369,7 @@ config ARCH_BCM2708
- select HAVE_SCHED_CLOCK
- select NEED_MACH_MEMORY_H
- select CLKDEV_LOOKUP
-+ select ARCH_HAS_CPUFREQ
- select GENERIC_CLOCKEVENTS
- select ARM_ERRATA_411920
- select MACH_BCM2708
-diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
-index 6e57543..bf40783 100644
---- a/drivers/cpufreq/Kconfig.arm
-+++ b/drivers/cpufreq/Kconfig.arm
-@@ -150,3 +150,11 @@ config ARM_SPEAR_CPUFREQ
- default y
- help
- This adds the CPUFreq driver support for SPEAr SOCs.
-+
-+config ARM_BCM2835_CPUFREQ
-+ bool "BCM2835 Driver"
-+ default y
-+ help
-+ This adds the CPUFreq driver for BCM2835
-+
-+ If in doubt, say N.
-diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
-index 3b95322..3a30bab 100644
---- a/drivers/cpufreq/Makefile
-+++ b/drivers/cpufreq/Makefile
-@@ -72,6 +72,7 @@ obj-$(CONFIG_ARM_SA1100_CPUFREQ) += sa1100-cpufreq.o
- obj-$(CONFIG_ARM_SA1110_CPUFREQ) += sa1110-cpufreq.o
- obj-$(CONFIG_ARM_SPEAR_CPUFREQ) += spear-cpufreq.o
- obj-$(CONFIG_ARCH_TEGRA) += tegra-cpufreq.o
-+obj-$(CONFIG_ARM_BCM2835_CPUFREQ) += bcm2835-cpufreq.o
-
- ##################################################################################
- # PowerPC platform drivers
-diff --git a/drivers/cpufreq/bcm2835-cpufreq.c b/drivers/cpufreq/bcm2835-cpufreq.c
-new file mode 100755
-index 0000000..822139a
---- /dev/null
-+++ b/drivers/cpufreq/bcm2835-cpufreq.c
-@@ -0,0 +1,239 @@
-+/*****************************************************************************
-+* Copyright 2011 Broadcom Corporation. All rights reserved.
-+*
-+* Unless you and Broadcom execute a separate written software license
-+* agreement governing use of this software, this software is licensed to you
-+* under the terms of the GNU General Public License version 2, available at
-+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
-+*
-+* Notwithstanding the above, under no circumstances may you combine this
-+* software in any way with any other Broadcom software provided under a
-+* license other than the GPL, without Broadcom's express prior written
-+* consent.
-+*****************************************************************************/
-+
-+/*****************************************************************************
-+* FILENAME: bcm2835-cpufreq.h
-+* DESCRIPTION: This driver dynamically manages the CPU Frequency of the ARM
-+* processor. Messages are sent to Videocore either setting or requesting the
-+* frequency of the ARM in order to match an appropiate frequency to the current
-+* usage of the processor. The policy which selects the frequency to use is
-+* defined in the kernel .config file, but can be changed during runtime.
-+*****************************************************************************/
-+
-+/* ---------- INCLUDES ---------- */
-+#include <linux/kernel.h>
-+#include <linux/init.h>
-+#include <linux/module.h>
-+#include <linux/cpufreq.h>
-+#include <mach/vcio.h>
-+
-+/* ---------- DEFINES ---------- */
-+/*#define CPUFREQ_DEBUG_ENABLE*/ /* enable debugging */
-+#define MODULE_NAME "bcm2835-cpufreq"
-+
-+#define VCMSG_ID_ARM_CLOCK 0x000000003 /* Clock/Voltage ID's */
-+
-+/* debug printk macros */
-+#ifdef CPUFREQ_DEBUG_ENABLE
-+#define print_debug(fmt,...) pr_debug("%s:%s:%d: "fmt, MODULE_NAME, __func__, __LINE__, ##__VA_ARGS__)
-+#else
-+#define print_debug(fmt,...)
-+#endif
-+#define print_err(fmt,...) pr_err("%s:%s:%d: "fmt, MODULE_NAME, __func__,__LINE__, ##__VA_ARGS__)
-+#define print_info(fmt,...) pr_info("%s: "fmt, MODULE_NAME, ##__VA_ARGS__)
-+
-+/* tag part of the message */
-+struct vc_msg_tag {
-+ uint32_t tag_id; /* the message id */
-+ uint32_t buffer_size; /* size of the buffer (which in this case is always 8 bytes) */
-+ uint32_t data_size; /* amount of data being sent or received */
-+ uint32_t dev_id; /* the ID of the clock/voltage to get or set */
-+ uint32_t val; /* the value (e.g. rate (in Hz)) to set */
-+};
-+
-+/* message structure to be sent to videocore */
-+struct vc_msg {
-+ uint32_t msg_size; /* simply, sizeof(struct vc_msg) */
-+ uint32_t request_code; /* holds various information like the success and number of bytes returned (refer to mailboxes wiki) */
-+ struct vc_msg_tag tag; /* the tag structure above to make */
-+ uint32_t end_tag; /* an end identifier, should be set to NULL */
-+};
-+
-+/* ---------- GLOBALS ---------- */
-+static struct cpufreq_driver bcm2835_cpufreq_driver; /* the cpufreq driver global */
-+
-+/*
-+ ===============================================
-+ clk_rate either gets or sets the clock rates.
-+ ===============================================
-+*/
-+static uint32_t bcm2835_cpufreq_set_clock(int cur_rate, int arm_rate)
-+{
-+ int s, actual_rate=0;
-+ struct vc_msg msg;
-+
-+ /* wipe all previous message data */
-+ memset(&msg, 0, sizeof msg);
-+
-+ msg.msg_size = sizeof msg;
-+
-+ msg.tag.tag_id = VCMSG_SET_CLOCK_RATE;
-+ msg.tag.buffer_size = 8;
-+ msg.tag.data_size = 8; /* we're sending the clock ID and the new rates which is a total of 2 words */
-+ msg.tag.dev_id = VCMSG_ID_ARM_CLOCK;
-+ msg.tag.val = arm_rate * 1000;
-+
-+ /* send the message */
-+ s = bcm_mailbox_property(&msg, sizeof msg);
-+
-+ /* check if it was all ok and return the rate in KHz */
-+ if (s == 0 && (msg.request_code & 0x80000000))
-+ actual_rate = msg.tag.val/1000;
-+
-+ print_debug("Setting new frequency = %d -> %d (actual %d)\n", cur_rate, arm_rate, actual_rate);
-+ return actual_rate;
-+}
-+
-+static uint32_t bcm2835_cpufreq_get_clock(int tag)
-+{
-+ int s;
-+ int arm_rate = 0;
-+ struct vc_msg msg;
-+
-+ /* wipe all previous message data */
-+ memset(&msg, 0, sizeof msg);
-+
-+ msg.msg_size = sizeof msg;
-+ msg.tag.tag_id = tag;
-+ msg.tag.buffer_size = 8;
-+ msg.tag.data_size = 4; /* we're just sending the clock ID which is one word long */
-+ msg.tag.dev_id = VCMSG_ID_ARM_CLOCK;
-+
-+ /* send the message */
-+ s = bcm_mailbox_property(&msg, sizeof msg);
-+
-+ /* check if it was all ok and return the rate in KHz */
-+ if (s == 0 && (msg.request_code & 0x80000000))
-+ arm_rate = msg.tag.val/1000;
-+
-+ print_debug("%s frequency = %d\n",
-+ tag == VCMSG_GET_CLOCK_RATE ? "Current":
-+ tag == VCMSG_GET_MIN_CLOCK ? "Min":
-+ tag == VCMSG_GET_MAX_CLOCK ? "Max":
-+ "Unexpected", arm_rate);
-+
-+ return arm_rate;
-+}
-+
-+/*
-+ ====================================================
-+ Module Initialisation registers the cpufreq driver
-+ ====================================================
-+*/
-+static int __init bcm2835_cpufreq_module_init(void)
-+{
-+ print_debug("IN\n");
-+ return cpufreq_register_driver(&bcm2835_cpufreq_driver);
-+}
-+
-+/*
-+ =============
-+ Module exit
-+ =============
-+*/
-+static void __exit bcm2835_cpufreq_module_exit(void)
-+{
-+ print_debug("IN\n");
-+ cpufreq_unregister_driver(&bcm2835_cpufreq_driver);
-+ return;
-+}
-+
-+/*
-+ ==============================================================
-+ Initialisation function sets up the CPU policy for first use
-+ ==============================================================
-+*/
-+static int bcm2835_cpufreq_driver_init(struct cpufreq_policy *policy)
-+{
-+ /* measured value of how long it takes to change frequency */
-+ policy->cpuinfo.transition_latency = 355000; /* ns */
-+
-+ /* now find out what the maximum and minimum frequencies are */
-+ policy->min = policy->cpuinfo.min_freq = bcm2835_cpufreq_get_clock(VCMSG_GET_MIN_CLOCK);
-+ policy->max = policy->cpuinfo.max_freq = bcm2835_cpufreq_get_clock(VCMSG_GET_MAX_CLOCK);
-+ policy->cur = bcm2835_cpufreq_get_clock(VCMSG_GET_CLOCK_RATE);
-+
-+ print_info("min=%d max=%d cur=%d\n", policy->min, policy->max, policy->cur);
-+ return 0;
-+}
-+
-+/*
-+ =================================================================================
-+ Target function chooses the most appropriate frequency from the table to enable
-+ =================================================================================
-+*/
-+
-+static int bcm2835_cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation)
-+{
-+ unsigned int target = target_freq;
-+ unsigned int cur = policy->cur;
-+ print_debug("%s: min=%d max=%d cur=%d target=%d\n",policy->governor->name,policy->min,policy->max,policy->cur,target_freq);
-+
-+ /* if we are above min and using ondemand, then just use max */
-+ if (strcmp("ondemand", policy->governor->name)==0 && target > policy->min)
-+ target = policy->max;
-+ /* if the frequency is the same, just quit */
-+ if (target == policy->cur)
-+ return 0;
-+
-+ /* otherwise were good to set the clock frequency */
-+ policy->cur = bcm2835_cpufreq_set_clock(policy->cur, target);
-+
-+ if (!policy->cur)
-+ {
-+ print_err("Error occurred setting a new frequency (%d)!\n", target);
-+ policy->cur = bcm2835_cpufreq_get_clock(VCMSG_GET_CLOCK_RATE);
-+ return -EINVAL;
-+ }
-+ print_debug("Freq %d->%d (min=%d max=%d target=%d request=%d)\n", cur, policy->cur, policy->min, policy->max, target_freq, target);
-+ return 0;
-+}
-+
-+static unsigned int bcm2835_cpufreq_driver_get(unsigned int cpu)
-+{
-+ unsigned int actual_rate = bcm2835_cpufreq_get_clock(VCMSG_GET_CLOCK_RATE);
-+ print_debug("cpu=%d\n", actual_rate);
-+ return actual_rate;
-+}
-+
-+/*
-+ =================================================================================
-+ Verify ensures that when a policy is changed, it is suitable for the CPU to use
-+ =================================================================================
-+*/
-+
-+static int bcm2835_cpufreq_driver_verify(struct cpufreq_policy *policy)
-+{
-+ print_info("switching to governor %s\n", policy->governor->name);
-+ return 0;
-+}
-+
-+
-+/* the CPUFreq driver */
-+static struct cpufreq_driver bcm2835_cpufreq_driver = {
-+ .name = "BCM2835 CPUFreq",
-+ .owner = THIS_MODULE,
-+ .init = bcm2835_cpufreq_driver_init,
-+ .verify = bcm2835_cpufreq_driver_verify,
-+ .target = bcm2835_cpufreq_driver_target,
-+ .get = bcm2835_cpufreq_driver_get
-+};
-+
-+MODULE_AUTHOR("Dorian Peake and Dom Cobley");
-+MODULE_DESCRIPTION("CPU frequency driver for BCM2835 chip");
-+MODULE_LICENSE("GPL");
-+
-+module_init(bcm2835_cpufreq_module_init);
-+module_exit(bcm2835_cpufreq_module_exit);
-+
---
-1.9.1
-
projects / 15.05 / openwrt.git / blobdiff