summaryrefslogtreecommitdiff
path: root/drivers/devfreq
diff options
context:
space:
mode:
authorMarc Zyngier <maz@kernel.org>2020-06-30 11:05:46 +0100
committerChanwoo Choi <cw00.choi@samsung.com>2020-07-30 17:22:57 +0900
commit63ef91f24f9bfc70b6446319f6cabfd094481372 (patch)
tree3602a3ad48d4107531e4df228abcc05f0c9f1ad5 /drivers/devfreq
parent92ed301919932f777713b9172e525674157e983d (diff)
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 9173c5ceb035 ("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: 9173c5ceb035 ("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>
Diffstat (limited to 'drivers/devfreq')
-rw-r--r--drivers/devfreq/rk3399_dmc.c42
1 files changed, 23 insertions, 19 deletions
diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
index 24f04f78285b..027769e39f9b 100644
--- a/drivers/devfreq/rk3399_dmc.c
+++ b/drivers/devfreq/rk3399_dmc.c
@@ -95,18 +95,20 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
mutex_lock(&dmcfreq->lock);
- 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 (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.
@@ -371,13 +373,14 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
}
node = of_parse_phandle(np, "rockchip,pmu", 0);
- if (node) {
- 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;
- }
+ 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);
@@ -399,6 +402,7 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
goto err_edev;
};
+no_pmu:
arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
ROCKCHIP_SIP_CONFIG_DRAM_INIT,
0, 0, 0, 0, &res);