| From 63ef91f24f9bfc70b6446319f6cabfd094481372 Mon Sep 17 00:00:00 2001 |
| From: Marc Zyngier <maz@kernel.org> |
| Date: Tue, 30 Jun 2020 11:05:46 +0100 |
| Subject: PM / devfreq: rk3399_dmc: Fix kernel oops when rockchip,pmu is absent |
| |
| From: Marc Zyngier <maz@kernel.org> |
| |
| commit 63ef91f24f9bfc70b6446319f6cabfd094481372 upstream. |
| |
| 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> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/devfreq/rk3399_dmc.c | 42 +++++++++++++++++++++++------------------- |
| 1 file changed, 23 insertions(+), 19 deletions(-) |
| |
| --- a/drivers/devfreq/rk3399_dmc.c |
| +++ b/drivers/devfreq/rk3399_dmc.c |
| @@ -95,18 +95,20 @@ static int rk3399_dmcfreq_target(struct |
| |
| 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 p |
| } |
| |
| 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 p |
| goto err_edev; |
| }; |
| |
| +no_pmu: |
| arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0, |
| ROCKCHIP_SIP_CONFIG_DRAM_INIT, |
| 0, 0, 0, 0, &res); |