linux/drivers/devfreq/rk3399_dmc.c
Marc Zyngier 63ef91f24f PM / devfreq: rk3399_dmc: Fix kernel oops when rockchip,pmu is absent
Booting a recent kernel on a rk3399-based system (nanopc-t4),
equipped with a recent u-boot and ATF results in an Oops due
to a NULL pointer dereference.

This turns out to be due to the rk3399-dmc driver looking for
an *undocumented* property (rockchip,pmu), and happily using
a NULL pointer when the property isn't there.

Instead, make most of what was brought in with 9173c5ceb0
("PM / devfreq: rk3399_dmc: Pass ODT and auto power down parameters
to TF-A.") conditioned on finding this property in the device-tree,
preventing the driver from exploding.

Cc: stable@vger.kernel.org
Fixes: 9173c5ceb0 ("PM / devfreq: rk3399_dmc: Pass ODT and auto power down parameters to TF-A.")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2020-07-30 17:22:57 +09:00

517 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd.
* Author: Lin Huang <hl@rock-chips.com>
*/
#include <linux/arm-smccc.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/devfreq.h>
#include <linux/devfreq-event.h>
#include <linux/interrupt.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/rwsem.h>
#include <linux/suspend.h>
#include <soc/rockchip/rk3399_grf.h>
#include <soc/rockchip/rockchip_sip.h>
struct dram_timing {
unsigned int ddr3_speed_bin;
unsigned int pd_idle;
unsigned int sr_idle;
unsigned int sr_mc_gate_idle;
unsigned int srpd_lite_idle;
unsigned int standby_idle;
unsigned int auto_pd_dis_freq;
unsigned int dram_dll_dis_freq;
unsigned int phy_dll_dis_freq;
unsigned int ddr3_odt_dis_freq;
unsigned int ddr3_drv;
unsigned int ddr3_odt;
unsigned int phy_ddr3_ca_drv;
unsigned int phy_ddr3_dq_drv;
unsigned int phy_ddr3_odt;
unsigned int lpddr3_odt_dis_freq;
unsigned int lpddr3_drv;
unsigned int lpddr3_odt;
unsigned int phy_lpddr3_ca_drv;
unsigned int phy_lpddr3_dq_drv;
unsigned int phy_lpddr3_odt;
unsigned int lpddr4_odt_dis_freq;
unsigned int lpddr4_drv;
unsigned int lpddr4_dq_odt;
unsigned int lpddr4_ca_odt;
unsigned int phy_lpddr4_ca_drv;
unsigned int phy_lpddr4_ck_cs_drv;
unsigned int phy_lpddr4_dq_drv;
unsigned int phy_lpddr4_odt;
};
struct rk3399_dmcfreq {
struct device *dev;
struct devfreq *devfreq;
struct devfreq_simple_ondemand_data ondemand_data;
struct clk *dmc_clk;
struct devfreq_event_dev *edev;
struct mutex lock;
struct dram_timing timing;
struct regulator *vdd_center;
struct regmap *regmap_pmu;
unsigned long rate, target_rate;
unsigned long volt, target_volt;
unsigned int odt_dis_freq;
int odt_pd_arg0, odt_pd_arg1;
};
static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
u32 flags)
{
struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
struct dev_pm_opp *opp;
unsigned long old_clk_rate = dmcfreq->rate;
unsigned long target_volt, target_rate;
struct arm_smccc_res res;
bool odt_enable = false;
int err;
opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(opp))
return PTR_ERR(opp);
target_rate = dev_pm_opp_get_freq(opp);
target_volt = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
if (dmcfreq->rate == target_rate)
return 0;
mutex_lock(&dmcfreq->lock);
if (dmcfreq->regmap_pmu) {
if (target_rate >= dmcfreq->odt_dis_freq)
odt_enable = true;
/*
* This makes a SMC call to the TF-A to set the DDR PD
* (power-down) timings and to enable or disable the
* ODT (on-die termination) resistors.
*/
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, dmcfreq->odt_pd_arg0,
dmcfreq->odt_pd_arg1,
ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD,
odt_enable, 0, 0, 0, &res);
}
/*
* If frequency scaling from low to high, adjust voltage first.
* If frequency scaling from high to low, adjust frequency first.
*/
if (old_clk_rate < target_rate) {
err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
target_volt);
if (err) {
dev_err(dev, "Cannot set voltage %lu uV\n",
target_volt);
goto out;
}
}
err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
if (err) {
dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
err);
regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
dmcfreq->volt);
goto out;
}
/*
* Check the dpll rate,
* There only two result we will get,
* 1. Ddr frequency scaling fail, we still get the old rate.
* 2. Ddr frequency scaling sucessful, we get the rate we set.
*/
dmcfreq->rate = clk_get_rate(dmcfreq->dmc_clk);
/* If get the incorrect rate, set voltage to old value. */
if (dmcfreq->rate != target_rate) {
dev_err(dev, "Got wrong frequency, Request %lu, Current %lu\n",
target_rate, dmcfreq->rate);
regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
dmcfreq->volt);
goto out;
} else if (old_clk_rate > target_rate)
err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
target_volt);
if (err)
dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
dmcfreq->rate = target_rate;
dmcfreq->volt = target_volt;
out:
mutex_unlock(&dmcfreq->lock);
return err;
}
static int rk3399_dmcfreq_get_dev_status(struct device *dev,
struct devfreq_dev_status *stat)
{
struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
struct devfreq_event_data edata;
int ret = 0;
ret = devfreq_event_get_event(dmcfreq->edev, &edata);
if (ret < 0)
return ret;
stat->current_frequency = dmcfreq->rate;
stat->busy_time = edata.load_count;
stat->total_time = edata.total_count;
return ret;
}
static int rk3399_dmcfreq_get_cur_freq(struct device *dev, unsigned long *freq)
{
struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
*freq = dmcfreq->rate;
return 0;
}
static struct devfreq_dev_profile rk3399_devfreq_dmc_profile = {
.polling_ms = 200,
.target = rk3399_dmcfreq_target,
.get_dev_status = rk3399_dmcfreq_get_dev_status,
.get_cur_freq = rk3399_dmcfreq_get_cur_freq,
};
static __maybe_unused int rk3399_dmcfreq_suspend(struct device *dev)
{
struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
int ret = 0;
ret = devfreq_event_disable_edev(dmcfreq->edev);
if (ret < 0) {
dev_err(dev, "failed to disable the devfreq-event devices\n");
return ret;
}
ret = devfreq_suspend_device(dmcfreq->devfreq);
if (ret < 0) {
dev_err(dev, "failed to suspend the devfreq devices\n");
return ret;
}
return 0;
}
static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
{
struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(dev);
int ret = 0;
ret = devfreq_event_enable_edev(dmcfreq->edev);
if (ret < 0) {
dev_err(dev, "failed to enable the devfreq-event devices\n");
return ret;
}
ret = devfreq_resume_device(dmcfreq->devfreq);
if (ret < 0) {
dev_err(dev, "failed to resume the devfreq devices\n");
return ret;
}
return ret;
}
static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
rk3399_dmcfreq_resume);
static int of_get_ddr_timings(struct dram_timing *timing,
struct device_node *np)
{
int ret = 0;
ret = of_property_read_u32(np, "rockchip,ddr3_speed_bin",
&timing->ddr3_speed_bin);
ret |= of_property_read_u32(np, "rockchip,pd_idle",
&timing->pd_idle);
ret |= of_property_read_u32(np, "rockchip,sr_idle",
&timing->sr_idle);
ret |= of_property_read_u32(np, "rockchip,sr_mc_gate_idle",
&timing->sr_mc_gate_idle);
ret |= of_property_read_u32(np, "rockchip,srpd_lite_idle",
&timing->srpd_lite_idle);
ret |= of_property_read_u32(np, "rockchip,standby_idle",
&timing->standby_idle);
ret |= of_property_read_u32(np, "rockchip,auto_pd_dis_freq",
&timing->auto_pd_dis_freq);
ret |= of_property_read_u32(np, "rockchip,dram_dll_dis_freq",
&timing->dram_dll_dis_freq);
ret |= of_property_read_u32(np, "rockchip,phy_dll_dis_freq",
&timing->phy_dll_dis_freq);
ret |= of_property_read_u32(np, "rockchip,ddr3_odt_dis_freq",
&timing->ddr3_odt_dis_freq);
ret |= of_property_read_u32(np, "rockchip,ddr3_drv",
&timing->ddr3_drv);
ret |= of_property_read_u32(np, "rockchip,ddr3_odt",
&timing->ddr3_odt);
ret |= of_property_read_u32(np, "rockchip,phy_ddr3_ca_drv",
&timing->phy_ddr3_ca_drv);
ret |= of_property_read_u32(np, "rockchip,phy_ddr3_dq_drv",
&timing->phy_ddr3_dq_drv);
ret |= of_property_read_u32(np, "rockchip,phy_ddr3_odt",
&timing->phy_ddr3_odt);
ret |= of_property_read_u32(np, "rockchip,lpddr3_odt_dis_freq",
&timing->lpddr3_odt_dis_freq);
ret |= of_property_read_u32(np, "rockchip,lpddr3_drv",
&timing->lpddr3_drv);
ret |= of_property_read_u32(np, "rockchip,lpddr3_odt",
&timing->lpddr3_odt);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_ca_drv",
&timing->phy_lpddr3_ca_drv);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_dq_drv",
&timing->phy_lpddr3_dq_drv);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr3_odt",
&timing->phy_lpddr3_odt);
ret |= of_property_read_u32(np, "rockchip,lpddr4_odt_dis_freq",
&timing->lpddr4_odt_dis_freq);
ret |= of_property_read_u32(np, "rockchip,lpddr4_drv",
&timing->lpddr4_drv);
ret |= of_property_read_u32(np, "rockchip,lpddr4_dq_odt",
&timing->lpddr4_dq_odt);
ret |= of_property_read_u32(np, "rockchip,lpddr4_ca_odt",
&timing->lpddr4_ca_odt);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ca_drv",
&timing->phy_lpddr4_ca_drv);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_ck_cs_drv",
&timing->phy_lpddr4_ck_cs_drv);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_dq_drv",
&timing->phy_lpddr4_dq_drv);
ret |= of_property_read_u32(np, "rockchip,phy_lpddr4_odt",
&timing->phy_lpddr4_odt);
return ret;
}
static int rk3399_dmcfreq_probe(struct platform_device *pdev)
{
struct arm_smccc_res res;
struct device *dev = &pdev->dev;
struct device_node *np = pdev->dev.of_node, *node;
struct rk3399_dmcfreq *data;
int ret, index, size;
uint32_t *timing;
struct dev_pm_opp *opp;
u32 ddr_type;
u32 val;
data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
if (!data)
return -ENOMEM;
mutex_init(&data->lock);
data->vdd_center = devm_regulator_get(dev, "center");
if (IS_ERR(data->vdd_center)) {
if (PTR_ERR(data->vdd_center) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_err(dev, "Cannot get the regulator \"center\"\n");
return PTR_ERR(data->vdd_center);
}
data->dmc_clk = devm_clk_get(dev, "dmc_clk");
if (IS_ERR(data->dmc_clk)) {
if (PTR_ERR(data->dmc_clk) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_err(dev, "Cannot get the clk dmc_clk\n");
return PTR_ERR(data->dmc_clk);
}
data->edev = devfreq_event_get_edev_by_phandle(dev, 0);
if (IS_ERR(data->edev))
return -EPROBE_DEFER;
ret = devfreq_event_enable_edev(data->edev);
if (ret < 0) {
dev_err(dev, "failed to enable devfreq-event devices\n");
return ret;
}
/*
* Get dram timing and pass it to arm trust firmware,
* the dram driver in arm trust firmware will get these
* timing and to do dram initial.
*/
if (!of_get_ddr_timings(&data->timing, np)) {
timing = &data->timing.ddr3_speed_bin;
size = sizeof(struct dram_timing) / 4;
for (index = 0; index < size; index++) {
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, *timing++, index,
ROCKCHIP_SIP_CONFIG_DRAM_SET_PARAM,
0, 0, 0, 0, &res);
if (res.a0) {
dev_err(dev, "Failed to set dram param: %ld\n",
res.a0);
ret = -EINVAL;
goto err_edev;
}
}
}
node = of_parse_phandle(np, "rockchip,pmu", 0);
if (!node)
goto no_pmu;
data->regmap_pmu = syscon_node_to_regmap(node);
of_node_put(node);
if (IS_ERR(data->regmap_pmu)) {
ret = PTR_ERR(data->regmap_pmu);
goto err_edev;
}
regmap_read(data->regmap_pmu, RK3399_PMUGRF_OS_REG2, &val);
ddr_type = (val >> RK3399_PMUGRF_DDRTYPE_SHIFT) &
RK3399_PMUGRF_DDRTYPE_MASK;
switch (ddr_type) {
case RK3399_PMUGRF_DDRTYPE_DDR3:
data->odt_dis_freq = data->timing.ddr3_odt_dis_freq;
break;
case RK3399_PMUGRF_DDRTYPE_LPDDR3:
data->odt_dis_freq = data->timing.lpddr3_odt_dis_freq;
break;
case RK3399_PMUGRF_DDRTYPE_LPDDR4:
data->odt_dis_freq = data->timing.lpddr4_odt_dis_freq;
break;
default:
ret = -EINVAL;
goto err_edev;
};
no_pmu:
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
ROCKCHIP_SIP_CONFIG_DRAM_INIT,
0, 0, 0, 0, &res);
/*
* In TF-A there is a platform SIP call to set the PD (power-down)
* timings and to enable or disable the ODT (on-die termination).
* This call needs three arguments as follows:
*
* arg0:
* bit[0-7] : sr_idle
* bit[8-15] : sr_mc_gate_idle
* bit[16-31] : standby idle
* arg1:
* bit[0-11] : pd_idle
* bit[16-27] : srpd_lite_idle
* arg2:
* bit[0] : odt enable
*/
data->odt_pd_arg0 = (data->timing.sr_idle & 0xff) |
((data->timing.sr_mc_gate_idle & 0xff) << 8) |
((data->timing.standby_idle & 0xffff) << 16);
data->odt_pd_arg1 = (data->timing.pd_idle & 0xfff) |
((data->timing.srpd_lite_idle & 0xfff) << 16);
/*
* We add a devfreq driver to our parent since it has a device tree node
* with operating points.
*/
if (dev_pm_opp_of_add_table(dev)) {
dev_err(dev, "Invalid operating-points in device tree.\n");
ret = -EINVAL;
goto err_edev;
}
of_property_read_u32(np, "upthreshold",
&data->ondemand_data.upthreshold);
of_property_read_u32(np, "downdifferential",
&data->ondemand_data.downdifferential);
data->rate = clk_get_rate(data->dmc_clk);
opp = devfreq_recommended_opp(dev, &data->rate, 0);
if (IS_ERR(opp)) {
ret = PTR_ERR(opp);
goto err_free_opp;
}
data->rate = dev_pm_opp_get_freq(opp);
data->volt = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
rk3399_devfreq_dmc_profile.initial_freq = data->rate;
data->devfreq = devm_devfreq_add_device(dev,
&rk3399_devfreq_dmc_profile,
DEVFREQ_GOV_SIMPLE_ONDEMAND,
&data->ondemand_data);
if (IS_ERR(data->devfreq)) {
ret = PTR_ERR(data->devfreq);
goto err_free_opp;
}
devm_devfreq_register_opp_notifier(dev, data->devfreq);
data->dev = dev;
platform_set_drvdata(pdev, data);
return 0;
err_free_opp:
dev_pm_opp_of_remove_table(&pdev->dev);
err_edev:
devfreq_event_disable_edev(data->edev);
return ret;
}
static int rk3399_dmcfreq_remove(struct platform_device *pdev)
{
struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(&pdev->dev);
/*
* Before remove the opp table we need to unregister the opp notifier.
*/
devm_devfreq_unregister_opp_notifier(dmcfreq->dev, dmcfreq->devfreq);
dev_pm_opp_of_remove_table(dmcfreq->dev);
return 0;
}
static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
{ .compatible = "rockchip,rk3399-dmc" },
{ },
};
MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
static struct platform_driver rk3399_dmcfreq_driver = {
.probe = rk3399_dmcfreq_probe,
.remove = rk3399_dmcfreq_remove,
.driver = {
.name = "rk3399-dmc-freq",
.pm = &rk3399_dmcfreq_pm,
.of_match_table = rk3399dmc_devfreq_of_match,
},
};
module_platform_driver(rk3399_dmcfreq_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Lin Huang <hl@rock-chips.com>");
MODULE_DESCRIPTION("RK3399 dmcfreq driver with devfreq framework");