diff options
Diffstat (limited to 'arch/arm/mach-msm/avs.c')
| -rw-r--r-- | arch/arm/mach-msm/avs.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/avs.c b/arch/arm/mach-msm/avs.c new file mode 100644 index 000000000000..297d3e1a4d52 --- /dev/null +++ b/arch/arm/mach-msm/avs.c @@ -0,0 +1,323 @@ +/* + * Copyright (c) 2009, Code Aurora Forum. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of Code Aurora Forum nor + * the names of its contributors may be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * Alternatively, provided that this notice is retained in full, this software + * may be relicensed by the recipient under the terms of the GNU General Public + * License version 2 ("GPL") and only version 2, in which case the provisions of + * the GPL apply INSTEAD OF those given above. If the recipient relicenses the + * software under the GPL, then the identification text in the MODULE_LICENSE + * macro must be changed to reflect "GPLv2" instead of "Dual BSD/GPL". Once a + * recipient changes the license terms to the GPL, subsequent recipients shall + * not relicense under alternate licensing terms, including the BSD or dual + * BSD/GPL terms. In addition, the following license statement immediately + * below and between the words START and END shall also then apply when this + * software is relicensed under the GPL: + * + * START + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 and only version 2 as + * published by the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * END + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/kernel_stat.h> +#include <linux/workqueue.h> + +#include "avs.h" + +#define AVSDSCR_INPUT 0x01004860 /* magic # from circuit designer */ +#define TSCSR_INPUT 0x00000001 /* enable temperature sense */ + +#define TEMPRS 16 /* total number of temperature regions */ +#define GET_TEMPR() (avs_get_tscsr() >> 28) /* scale TSCSR[CTEMP] to regions */ + +struct mutex avs_lock; + +static struct avs_state_s +{ + u32 freq_cnt; /* Frequencies supported list */ + short *avs_v; /* Dyanmically allocated storage for + * 2D table of voltages over temp & + * freq. Used as a set of 1D tables. + * Each table is for a single temp. + * For usage see avs_get_voltage + */ + int (*set_vdd) (int); /* Function Ptr for setting voltage */ + int changing; /* Clock frequency is changing */ + u32 freq_idx; /* Current frequency index */ + int vdd; /* Current ACPU voltage */ +} avs_state; + +/* + * Update the AVS voltage vs frequency table, for current temperature + * Adjust based on the AVS delay circuit hardware status + */ +static void avs_update_voltage_table(short *vdd_table) +{ + u32 avscsr; + int cpu; + int vu; + int l2; + int i; + u32 cur_freq_idx; + short cur_voltage; + + cur_freq_idx = avs_state.freq_idx; + cur_voltage = avs_state.vdd; + + avscsr = avs_test_delays(); + AVSDEBUG("avscsr=%x, avsdscr=%x\n", avscsr, avs_get_avsdscr()); + + /* + * Read the results for the various unit's AVS delay circuits + * 2=> up, 1=>down, 0=>no-change + */ + cpu = ((avscsr >> 23) & 2) + ((avscsr >> 16) & 1); + vu = ((avscsr >> 28) & 2) + ((avscsr >> 21) & 1); + l2 = ((avscsr >> 29) & 2) + ((avscsr >> 22) & 1); + + if ((cpu == 3) || (vu == 3) || (l2 == 3)) { + printk(KERN_ERR "AVS: Dly Synth O/P error\n"); + } else if ((cpu == 2) || (l2 == 2) || (vu == 2)) { + /* + * even if one oscillator asks for up, increase the voltage, + * as its an indication we are running outside the + * critical acceptable range of v-f combination. + */ + AVSDEBUG("cpu=%d l2=%d vu=%d\n", cpu, l2, vu); + AVSDEBUG("Voltage up at %d\n", cur_freq_idx); + + if (cur_voltage >= VOLTAGE_MAX) + printk(KERN_ERR + "AVS: Voltage can not get high enough!\n"); + + /* Raise the voltage for all frequencies */ + for (i = 0; i < avs_state.freq_cnt; i++) { + vdd_table[i] = cur_voltage + VOLTAGE_STEP; + if (vdd_table[i] > VOLTAGE_MAX) + vdd_table[i] = VOLTAGE_MAX; + } + } else if ((cpu == 1) && (l2 == 1) && (vu == 1)) { + if ((cur_voltage - VOLTAGE_STEP >= VOLTAGE_MIN) && + (cur_voltage <= vdd_table[cur_freq_idx])) { + vdd_table[cur_freq_idx] = cur_voltage - VOLTAGE_STEP; + AVSDEBUG("Voltage down for %d and lower levels\n", + cur_freq_idx); + + /* clamp to this voltage for all lower levels */ + for (i = 0; i < cur_freq_idx; i++) { + if (vdd_table[i] > vdd_table[cur_freq_idx]) + vdd_table[i] = vdd_table[cur_freq_idx]; + } + } + } +} + +/* + * Return the voltage for the target performance freq_idx and optionally + * use AVS hardware to check the present voltage freq_idx + */ +static short avs_get_target_voltage(int freq_idx, bool update_table) +{ + unsigned cur_tempr = GET_TEMPR(); + unsigned temp_index = cur_tempr*avs_state.freq_cnt; + + /* Table of voltages vs frequencies for this temp */ + short *vdd_table = avs_state.avs_v + temp_index; + + if (update_table) + avs_update_voltage_table(vdd_table); + + return vdd_table[freq_idx]; +} + + +/* + * Set the voltage for the freq_idx and optionally + * use AVS hardware to update the voltage + */ +static int avs_set_target_voltage(int freq_idx, bool update_table) +{ + int rc = 0; + int new_voltage = avs_get_target_voltage(freq_idx, update_table); + if (avs_state.vdd != new_voltage) { + AVSDEBUG("AVS setting V to %d mV @%d\n", + new_voltage, freq_idx); + rc = avs_state.set_vdd(new_voltage); + if (rc) + return rc; + avs_state.vdd = new_voltage; + } + return rc; +} + +/* + * Notify avs of clk frquency transition begin & end + */ +int avs_adjust_freq(u32 freq_idx, int begin) +{ + int rc = 0; + + if (!avs_state.set_vdd) { + /* AVS not initialized */ + return 0; + } + + if (freq_idx >= avs_state.freq_cnt) { + AVSDEBUG("Out of range :%d\n", freq_idx); + return -EINVAL; + } + + mutex_lock(&avs_lock); + if ((begin && (freq_idx > avs_state.freq_idx)) || + (!begin && (freq_idx < avs_state.freq_idx))) { + /* Update voltage before increasing frequency & + * after decreasing frequency + */ + rc = avs_set_target_voltage(freq_idx, 0); + if (rc) + goto aaf_out; + + avs_state.freq_idx = freq_idx; + } + avs_state.changing = begin; +aaf_out: + mutex_unlock(&avs_lock); + + return rc; +} + + +static struct delayed_work avs_work; +static struct workqueue_struct *kavs_wq; +#define AVS_DELAY ((CONFIG_HZ * 50 + 999) / 1000) + +static void do_avs_timer(struct work_struct *work) +{ + int cur_freq_idx; + + mutex_lock(&avs_lock); + if (!avs_state.changing) { + /* Only adjust the voltage if clk is stable */ + cur_freq_idx = avs_state.freq_idx; + avs_set_target_voltage(cur_freq_idx, 1); + } + mutex_unlock(&avs_lock); + queue_delayed_work_on(0, kavs_wq, &avs_work, AVS_DELAY); +} + + +static void __init avs_timer_init(void) +{ + INIT_DELAYED_WORK_DEFERRABLE(&avs_work, do_avs_timer); + queue_delayed_work_on(0, kavs_wq, &avs_work, AVS_DELAY); +} + +static void __exit avs_timer_exit(void) +{ + cancel_delayed_work(&avs_work); +} + +static int __init avs_work_init(void) +{ + kavs_wq = create_workqueue("avs"); + if (!kavs_wq) { + printk(KERN_ERR "AVS initialization failed\n"); + return -EFAULT; + } + avs_timer_init(); + + return 1; +} + +static void __exit avs_work_exit(void) +{ + avs_timer_exit(); + destroy_workqueue(kavs_wq); +} + +int __init avs_init(int (*set_vdd)(int), u32 freq_cnt, u32 freq_idx) +{ + int i; + + mutex_init(&avs_lock); + + if (freq_cnt == 0) + return -EINVAL; + + avs_state.freq_cnt = freq_cnt; + + if (freq_idx >= avs_state.freq_cnt) + return -EINVAL; + + avs_state.avs_v = kmalloc(TEMPRS * avs_state.freq_cnt * + sizeof(avs_state.avs_v[0]), GFP_KERNEL); + + if (avs_state.avs_v == 0) + return -ENOMEM; + + for (i = 0; i < TEMPRS*avs_state.freq_cnt; i++) + avs_state.avs_v[i] = VOLTAGE_MAX; + + avs_reset_delays(AVSDSCR_INPUT); + avs_set_tscsr(TSCSR_INPUT); + + avs_state.set_vdd = set_vdd; + avs_state.changing = 0; + avs_state.freq_idx = -1; + avs_state.vdd = -1; + avs_adjust_freq(freq_idx, 0); + + avs_work_init(); + + return 0; +} + +void __exit avs_exit() +{ + avs_work_exit(); + + kfree(avs_state.avs_v); +} + + |