M7350/kernel/arch/arm/mach-msm/acpuclock-cortex.c
2024-09-09 08:52:07 +00:00

427 lines
10 KiB
C

/*
* Copyright (c) 2013, The Linux Foundation. All rights reserved.
*
* 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.
*/
#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/cpufreq.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/iopoll.h>
#include <mach/board.h>
#include <mach/msm_iomap.h>
#include <mach/msm_bus.h>
#include <mach/msm_bus_board.h>
#include <mach/rpm-regulator.h>
#include <mach/clk-provider.h>
#include <mach/rpm-regulator-smd.h>
#include "acpuclock.h"
#include "acpuclock-cortex.h"
#define POLL_INTERVAL_US 1
#define APCS_RCG_UPDATE_TIMEOUT_US 20
static struct acpuclk_drv_data *priv;
static uint32_t bus_perf_client;
/* Update the bus bandwidth request. */
static void set_bus_bw(unsigned int bw)
{
int ret;
if (bw >= priv->bus_scale->num_usecases) {
pr_err("invalid bandwidth request (%d)\n", bw);
return;
}
/* Update bandwidth if request has changed. This may sleep. */
ret = msm_bus_scale_client_update_request(bus_perf_client, bw);
if (ret)
pr_err("bandwidth request failed (%d)\n", ret);
return;
}
/* Apply any voltage increases. */
static int increase_vdd(unsigned int vdd_cpu, unsigned int vdd_mem)
{
int rc = 0;
if (priv->vdd_mem) {
/*
* Increase vdd_mem before vdd_cpu. vdd_mem should
* be >= vdd_cpu.
*/
rc = regulator_set_voltage(priv->vdd_mem, vdd_mem,
priv->vdd_max_mem);
if (rc) {
pr_err("vdd_mem increase failed (%d)\n", rc);
return rc;
}
}
rc = regulator_set_voltage(priv->vdd_cpu, vdd_cpu, priv->vdd_max_cpu);
if (rc)
pr_err("vdd_cpu increase failed (%d)\n", rc);
return rc;
}
/* Apply any per-cpu voltage decreases. */
static void decrease_vdd(unsigned int vdd_cpu, unsigned int vdd_mem)
{
int ret;
/* Update CPU voltage. */
ret = regulator_set_voltage(priv->vdd_cpu, vdd_cpu, priv->vdd_max_cpu);
if (ret) {
pr_err("vdd_cpu decrease failed (%d)\n", ret);
return;
}
if (!priv->vdd_mem)
return;
/* Decrease vdd_mem after vdd_cpu. vdd_mem should be >= vdd_cpu. */
ret = regulator_set_voltage(priv->vdd_mem, vdd_mem, priv->vdd_max_mem);
if (ret)
pr_err("vdd_mem decrease failed (%d)\n", ret);
}
static void select_clk_source_div(struct acpuclk_drv_data *drv_data,
struct clkctl_acpu_speed *s)
{
u32 regval, rc, src_div;
void __iomem *apcs_rcg_config = drv_data->apcs_rcg_config;
void __iomem *apcs_rcg_cmd = drv_data->apcs_rcg_cmd;
struct acpuclk_reg_data *r = &drv_data->reg_data;
src_div = s->src_div ? ((2 * s->src_div) - 1) : s->src_div;
regval = readl_relaxed(apcs_rcg_config);
regval &= ~r->cfg_src_mask;
regval |= s->src_sel << r->cfg_src_shift;
regval &= ~r->cfg_div_mask;
regval |= src_div << r->cfg_div_shift;
writel_relaxed(regval, apcs_rcg_config);
/* Update the configuration */
regval = readl_relaxed(apcs_rcg_cmd);
regval |= r->update_mask;
writel_relaxed(regval, apcs_rcg_cmd);
/* Wait for the update to take effect */
rc = readl_poll_timeout_noirq(apcs_rcg_cmd, regval,
!(regval & r->poll_mask),
POLL_INTERVAL_US,
APCS_RCG_UPDATE_TIMEOUT_US);
if (rc)
pr_warn("acpu rcg didn't update its configuration\n");
}
static struct clkctl_acpu_speed *__init find_cur_cpu_level(void)
{
struct clkctl_acpu_speed *f, *max = priv->freq_tbl;
void __iomem *apcs_rcg_config = priv->apcs_rcg_config;
struct acpuclk_reg_data *r = &priv->reg_data;
u32 regval, div, src;
unsigned long rate;
struct clk *parent;
regval = readl_relaxed(apcs_rcg_config);
src = regval & r->cfg_src_mask;
src >>= r->cfg_src_shift;
div = regval & r->cfg_div_mask;
div >>= r->cfg_div_shift;
/* No support for half-integer dividers */
div = div > 1 ? (div + 1) / 2 : 0;
for (f = priv->freq_tbl; f->khz; f++) {
if (f->use_for_scaling)
max = f;
if (f->src_sel != src || f->src_div != div)
continue;
parent = priv->src_clocks[f->src].clk;
rate = parent->rate / (div ? div : 1);
if (f->khz * 1000 == rate)
break;
}
if (f->khz)
return f;
pr_err("CPUs are running at an unknown rate. Defaulting to %u KHz.\n",
max->khz);
/* Change to a safe frequency */
select_clk_source_div(priv, priv->freq_tbl);
/* Default to largest frequency */
return max;
}
static int set_speed_atomic(struct clkctl_acpu_speed *tgt_s)
{
struct clkctl_acpu_speed *strt_s = priv->current_speed;
struct clk *strt = priv->src_clocks[strt_s->src].clk;
struct clk *tgt = priv->src_clocks[tgt_s->src].clk;
int rc = 0;
WARN(strt_s->src == ACPUPLL && tgt_s->src == ACPUPLL,
"can't reprogram ACPUPLL during atomic context\n");
rc = clk_enable(tgt);
if (rc)
return rc;
select_clk_source_div(priv, tgt_s);
clk_disable(strt);
return rc;
}
static int set_speed(struct clkctl_acpu_speed *tgt_s)
{
int rc = 0;
unsigned int div = tgt_s->src_div ? tgt_s->src_div : 1;
unsigned int tgt_freq_hz = tgt_s->khz * 1000 * div;
struct clkctl_acpu_speed *strt_s = priv->current_speed;
struct clkctl_acpu_speed *cxo_s = &priv->freq_tbl[0];
struct clk *strt = priv->src_clocks[strt_s->src].clk;
struct clk *tgt = priv->src_clocks[tgt_s->src].clk;
if (strt_s->src == ACPUPLL && tgt_s->src == ACPUPLL) {
/* Switch to another always on src */
select_clk_source_div(priv, cxo_s);
/* Re-program acpu pll */
clk_disable_unprepare(tgt);
rc = clk_set_rate(tgt, tgt_freq_hz);
if (rc)
pr_err("Failed to set ACPU PLL to %u\n", tgt_freq_hz);
BUG_ON(clk_prepare_enable(tgt));
/* Switch back to acpu pll */
select_clk_source_div(priv, tgt_s);
} else if (strt_s->src != ACPUPLL && tgt_s->src == ACPUPLL) {
rc = clk_set_rate(tgt, tgt_freq_hz);
if (rc) {
pr_err("Failed to set ACPU PLL to %u\n", tgt_freq_hz);
return rc;
}
rc = clk_prepare_enable(tgt);
if (rc) {
pr_err("ACPU PLL enable failed\n");
return rc;
}
select_clk_source_div(priv, tgt_s);
clk_disable_unprepare(strt);
} else {
rc = clk_prepare_enable(tgt);
if (rc) {
pr_err("%s enable failed\n",
priv->src_clocks[tgt_s->src].name);
return rc;
}
select_clk_source_div(priv, tgt_s);
clk_disable_unprepare(strt);
}
return rc;
}
static int acpuclk_cortex_set_rate(int cpu, unsigned long rate,
enum setrate_reason reason)
{
struct clkctl_acpu_speed *tgt_s, *strt_s;
int rc = 0;
if (reason == SETRATE_CPUFREQ)
mutex_lock(&priv->lock);
strt_s = priv->current_speed;
/* Return early if rate didn't change */
if (rate == strt_s->khz && reason != SETRATE_INIT)
goto out;
/* Find target frequency */
for (tgt_s = priv->freq_tbl; tgt_s->khz != 0; tgt_s++)
if (tgt_s->khz == rate)
break;
if (tgt_s->khz == 0) {
rc = -EINVAL;
goto out;
}
/* Increase VDD levels if needed */
if ((reason == SETRATE_CPUFREQ)
&& (tgt_s->khz > strt_s->khz)) {
rc = increase_vdd(tgt_s->vdd_cpu, tgt_s->vdd_mem);
if (rc)
goto out;
}
pr_debug("Switching from CPU rate %u KHz -> %u KHz\n",
strt_s->khz, tgt_s->khz);
/* Switch CPU speed. Flag indicates atomic context */
if (reason == SETRATE_CPUFREQ || reason == SETRATE_INIT)
rc = set_speed(tgt_s);
else
rc = set_speed_atomic(tgt_s);
if (rc)
goto out;
priv->current_speed = tgt_s;
pr_debug("CPU speed change complete\n");
/* Nothing else to do for SWFI or power-collapse. */
if (reason == SETRATE_SWFI || reason == SETRATE_PC)
goto out;
/* Update bus bandwith request */
set_bus_bw(tgt_s->bw_level);
/* Drop VDD levels if we can. */
if (tgt_s->khz < strt_s->khz || reason == SETRATE_INIT)
decrease_vdd(tgt_s->vdd_cpu, tgt_s->vdd_mem);
out:
if (reason == SETRATE_CPUFREQ)
mutex_unlock(&priv->lock);
return rc;
}
static unsigned long acpuclk_cortex_get_rate(int cpu)
{
return priv->current_speed->khz;
}
#ifdef CONFIG_CPU_FREQ_MSM
static struct cpufreq_frequency_table freq_table[30];
static void __init cpufreq_table_init(void)
{
int i, freq_cnt = 0;
/* Construct the freq_table tables from priv->freq_tbl. */
for (i = 0; priv->freq_tbl[i].khz != 0
&& freq_cnt < ARRAY_SIZE(freq_table); i++) {
if (!priv->freq_tbl[i].use_for_scaling)
continue;
freq_table[freq_cnt].index = freq_cnt;
freq_table[freq_cnt].frequency = priv->freq_tbl[i].khz;
freq_cnt++;
}
/* freq_table not big enough to store all usable freqs. */
BUG_ON(priv->freq_tbl[i].khz != 0);
freq_table[freq_cnt].index = freq_cnt;
freq_table[freq_cnt].frequency = CPUFREQ_TABLE_END;
pr_info("CPU: %d scaling frequencies supported.\n", freq_cnt);
/* Register table with CPUFreq. */
for_each_possible_cpu(i)
cpufreq_frequency_table_get_attr(freq_table, i);
}
#else
static void __init cpufreq_table_init(void) {}
#endif
static struct acpuclk_data acpuclk_cortex_data = {
.set_rate = acpuclk_cortex_set_rate,
.get_rate = acpuclk_cortex_get_rate,
};
int __init acpuclk_cortex_init(struct platform_device *pdev,
struct acpuclk_drv_data *data)
{
int rc;
int parent;
priv = data;
mutex_init(&priv->lock);
acpuclk_cortex_data.power_collapse_khz = priv->wait_for_irq_khz;
acpuclk_cortex_data.wait_for_irq_khz = priv->wait_for_irq_khz;
bus_perf_client = msm_bus_scale_register_client(priv->bus_scale);
if (!bus_perf_client) {
pr_err("Unable to register bus client\n");
BUG();
}
/* Initialize regulators */
rc = increase_vdd(priv->vdd_max_cpu, priv->vdd_max_mem);
if (rc)
return rc;
if (priv->vdd_mem) {
rc = regulator_enable(priv->vdd_mem);
if (rc) {
dev_err(&pdev->dev, "regulator_enable for mem failed\n");
return rc;
}
}
rc = regulator_enable(priv->vdd_cpu);
if (rc) {
dev_err(&pdev->dev, "regulator_enable for cpu failed\n");
return rc;
}
priv->current_speed = find_cur_cpu_level();
parent = priv->current_speed->src;
rc = clk_prepare_enable(priv->src_clocks[parent].clk);
if (rc) {
dev_err(&pdev->dev, "handoff: prepare_enable failed\n");
return rc;
}
rc = acpuclk_cortex_set_rate(0, priv->current_speed->khz, SETRATE_INIT);
if (rc) {
dev_err(&pdev->dev, "handoff: set rate failed\n");
return rc;
}
acpuclk_register(&acpuclk_cortex_data);
cpufreq_table_init();
return 0;
}