From: Cristian Marussi cristian.marussi@arm.com
[ Upstream commit e0f1a30cf184821499eeb67daedd7a3f21bbcb0b ]
When, at probe time, an SCMI communication failure inhibits the capacity to query power domains states, such domains should be skipped.
Registering partially initialized SCMI power domains with genpd will causes kernel panic.
arm-scmi timed out in resp(caller: scmi_power_state_get+0xa4/0xd0) scmi-power-domain scmi_dev.2: failed to get state for domain 9 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000009f3691000 [0000000000000000] pgd=00000009f1ca0003, p4d=00000009f1ca0003, pud=00000009f35ea003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP CPU: 2 PID: 381 Comm: bash Not tainted 5.8.0-rc1-00011-gebd118c2cca8 #2 Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Jan 3 2020 Internal error: Oops: 96000006 [#1] PREEMPT SMP pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--) pc : of_genpd_add_provider_onecell+0x98/0x1f8 lr : of_genpd_add_provider_onecell+0x48/0x1f8 Call trace: of_genpd_add_provider_onecell+0x98/0x1f8 scmi_pm_domain_probe+0x174/0x1e8 scmi_dev_probe+0x90/0xe0 really_probe+0xe4/0x448 driver_probe_device+0xfc/0x168 device_driver_attach+0x7c/0x88 bind_store+0xe8/0x128 drv_attr_store+0x2c/0x40 sysfs_kf_write+0x4c/0x60 kernfs_fop_write+0x114/0x230 __vfs_write+0x24/0x50 vfs_write+0xbc/0x1e0 ksys_write+0x70/0xf8 __arm64_sys_write+0x24/0x30 el0_svc_common.constprop.3+0x94/0x160 do_el0_svc+0x2c/0x98 el0_sync_handler+0x148/0x1a8 el0_sync+0x158/0x180
Do not register any power domain that failed to be queried with genpd.
Fixes: 898216c97ed2 ("firmware: arm_scmi: add device power domain support using genpd") Link: https://lore.kernel.org/r/20200619220330.12217-1-cristian.marussi@arm.com Signed-off-by: Cristian Marussi cristian.marussi@arm.com Signed-off-by: Sudeep Holla sudeep.holla@arm.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/firmware/arm_scmi/scmi_pm_domain.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/firmware/arm_scmi/scmi_pm_domain.c index 87f737e01473c..041f8152272bf 100644 --- a/drivers/firmware/arm_scmi/scmi_pm_domain.c +++ b/drivers/firmware/arm_scmi/scmi_pm_domain.c @@ -85,7 +85,10 @@ static int scmi_pm_domain_probe(struct scmi_device *sdev) for (i = 0; i < num_domains; i++, scmi_pd++) { u32 state;
- domains[i] = &scmi_pd->genpd; + if (handle->power_ops->state_get(handle, i, &state)) { + dev_warn(dev, "failed to get state for domain %d\n", i); + continue; + }
scmi_pd->domain = i; scmi_pd->handle = handle; @@ -94,13 +97,10 @@ static int scmi_pm_domain_probe(struct scmi_device *sdev) scmi_pd->genpd.power_off = scmi_pd_power_off; scmi_pd->genpd.power_on = scmi_pd_power_on;
- if (handle->power_ops->state_get(handle, i, &state)) { - dev_warn(dev, "failed to get state for domain %d\n", i); - continue; - } - pm_genpd_init(&scmi_pd->genpd, NULL, state == SCMI_POWER_STATE_GENERIC_OFF); + + domains[i] = &scmi_pd->genpd; }
scmi_pd_data->domains = domains;