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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, 27 Jul 2022 at 23:59, Bhupesh Sharma wrote: > > > > On 7/28/22 2:26 AM, Dmitry Baryshkov wrote: > > On Wed, 27 Jul 2022 at 23:55, Bhupesh Sharma wrote: > >> > >> > >> > >> On 7/28/22 2:23 AM, Dmitry Baryshkov wrote: > >>> On Wed, 27 Jul 2022 at 23:15, Bhupesh Sharma wrote: > >>>> > >>>> Hi Dmitry, > >>>> > >>>> On 7/28/22 1:39 AM, Dmitry Baryshkov wrote: > >>>>> To ease debugging of PSCI supported features, add debugfs file called > >>>>> 'psci' describing PSCI and SMC CC versions, enabled features and > >>>>> options. > >>>>> > >>>>> Signed-off-by: Dmitry Baryshkov > >>>>> --- > >>>>> drivers/firmware/psci/psci.c | 112 ++++++++++++++++++++++++++++++++++- > >>>>> include/uapi/linux/psci.h | 9 +++ > >>>>> 2 files changed, 120 insertions(+), 1 deletion(-) > >>>>> > >>>>> diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c > >>>>> index b907768eea01..6595cc964635 100644 > >>>>> --- a/drivers/firmware/psci/psci.c > >>>>> +++ b/drivers/firmware/psci/psci.c > >>>>> @@ -9,6 +9,7 @@ > >>>>> #include > >>>>> #include > >>>>> #include > >>>>> +#include > >>>>> #include > >>>>> #include > >>>>> #include > >>>>> @@ -324,12 +325,121 @@ static void psci_sys_poweroff(void) > >>>>> invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); > >>>>> } > >>>>> > >>>>> -static int __init psci_features(u32 psci_func_id) > >>>>> +static int psci_features(u32 psci_func_id) > >>>> > >>>> This change doesn't seem related to the patch $SUBJECT. > >>>> Also is it really needed? If yes, probably this should be a separate patch. > >>> > >>> It is related and I don't think it should be moved to a separate > >>> patch. Removing the __init annotation from psci_features() is > >>> necessary to allow using psci_features() from psci_debufs_read(), > >>> which is definitely not an __init code. Otherwise reading from > >>> debugfs/psci would cause null pointer exceptions. > >> > >> Ok, and what is the behavior with CONFIG_DEBUG_FS = n? > >> Does your patch work well in that case? > > > > Yes. Any particular reasons for the question? > > Your debugfs changes in this patch are protected with CONFIG_DEBUG_FS, > while the __init code change is not. Yes. I'm _removing_ the __init. Making the function available after kernel frees the __init memory. I'd have understood your questions if I were making an opposite change, marking the function with __init. But in this case I doubt it makes any difference. > So, IMO its not really needed if CONFIG_DEBUG_FS is set to =n (hence > probably needs to be a separate patch). An overhead is pretty minimal. And all the troubles to make __init annotation depend on CONFIG_DEBUG_FS overweight this overhead. > > Thanks. > > >>>>> { > >>>>> return invoke_psci_fn(PSCI_1_0_FN_PSCI_FEATURES, > >>>>> psci_func_id, 0, 0); > >>>>> } > >>>>> > >>>>> +#ifdef CONFIG_DEBUG_FS > >>>>> + > >>>>> +#define PSCI_ID(ver, _name) \ > >>>>> + { .fn = PSCI_##ver##_FN_##_name, .name = #_name, } > >>>>> +#define PSCI_ID_NATIVE(ver, _name) \ > >>>>> + { .fn = PSCI_FN_NATIVE(ver, _name), .name = #_name, } > >>>>> + > >>>>> +/* A table of all optional functions */ > >>>>> +static const struct { > >>>>> + u32 fn; > >>>>> + const char *name; > >>>>> +} psci_fn_ids[] = { > >>>>> + PSCI_ID_NATIVE(0_2, MIGRATE), > >>>>> + PSCI_ID(0_2, MIGRATE_INFO_TYPE), > >>>>> + PSCI_ID_NATIVE(0_2, MIGRATE_INFO_UP_CPU), > >>>>> + PSCI_ID(1_0, CPU_FREEZE), > >>>>> + PSCI_ID_NATIVE(1_0, CPU_DEFAULT_SUSPEND), > >>>>> + PSCI_ID_NATIVE(1_0, NODE_HW_STATE), > >>>>> + PSCI_ID_NATIVE(1_0, SYSTEM_SUSPEND), > >>>>> + PSCI_ID(1_0, SET_SUSPEND_MODE), > >>>>> + PSCI_ID_NATIVE(1_0, STAT_RESIDENCY), > >>>>> + PSCI_ID_NATIVE(1_0, STAT_COUNT), > >>>>> + PSCI_ID_NATIVE(1_1, SYSTEM_RESET2), > >>>>> +}; > >>>>> + > >>>>> +static int psci_debugfs_read(struct seq_file *s, void *data) > >>>>> +{ > >>>>> + int feature, type, i; > >>>>> + u32 ver; > >>>>> + > >>>>> + ver = psci_ops.get_version(); > >>>>> + seq_printf(s, "PSCIv%d.%d\n", > >>>>> + PSCI_VERSION_MAJOR(ver), > >>>>> + PSCI_VERSION_MINOR(ver)); > >>>>> + > >>>>> + /* PSCI_FEATURES is available only starting from 1.0 */ > >>>>> + if (PSCI_VERSION_MAJOR(ver) < 1) > >>>>> + return 0; > >>>>> + > >>>>> + feature = psci_features(ARM_SMCCC_VERSION_FUNC_ID); > >>>>> + if (feature != PSCI_RET_NOT_SUPPORTED) { > >>>>> + ver = invoke_psci_fn(ARM_SMCCC_VERSION_FUNC_ID, 0, 0, 0); > >>>>> + seq_printf(s, "SMC Calling Convention v%d.%d\n", > >>>>> + PSCI_VERSION_MAJOR(ver), > >>>>> + PSCI_VERSION_MINOR(ver)); > >>>>> + } else { > >>>>> + seq_printf(s, "SMC Calling Convention v1.0 is assumed\n"); > >>>>> + } > >>>>> + > >>>>> + feature = psci_features(PSCI_FN_NATIVE(0_2, CPU_SUSPEND)); > >>>>> + if (feature < 0) { > >>>>> + seq_printf(s, "PSCI_FEATURES(CPU_SUSPEND) error (%d)\n", feature); > >>>>> + } else { > >>>>> + seq_printf(s, "OSI is %ssupported\n", > >>>>> + (feature & BIT(0)) ? "" : "not "); > >>>>> + seq_printf(s, "%s StateID format is used\n", > >>>>> + (feature & BIT(1)) ? "Extended" : "Original"); > >>>>> + } > >>>>> + > >>>>> + type = psci_ops.migrate_info_type(); > >>>>> + if (type == PSCI_0_2_TOS_UP_MIGRATE || > >>>>> + type == PSCI_0_2_TOS_UP_NO_MIGRATE) { > >>>>> + unsigned long cpuid; > >>>>> + > >>>>> + seq_printf(s, "Trusted OS %smigrate capable\n", > >>>>> + type == PSCI_0_2_TOS_UP_NO_MIGRATE ? "not " : ""); > >>>>> + cpuid = psci_migrate_info_up_cpu(); > >>>>> + seq_printf(s, "Trusted OS resident on physical CPU 0x%lx (#%d)\n", cpuid, resident_cpu); > >>>>> + } else if (type == PSCI_0_2_TOS_MP) { > >>>>> + seq_printf(s, "Trusted OS migration not required\n"); > >>>>> + } else { > >>>>> + if (type != PSCI_RET_NOT_SUPPORTED) > >>>>> + seq_printf(s, "MIGRATE_INFO_TYPE returned unknown type (%d)\n", type); > >>>>> + } > >>>>> + > >>>>> + for (i = 0; i < ARRAY_SIZE(psci_fn_ids); i++) { > >>>>> + feature = psci_features(psci_fn_ids[i].fn); > >>>>> + if (feature == PSCI_RET_NOT_SUPPORTED) > >>>>> + continue; > >>>>> + if (feature < 0) > >>>>> + seq_printf(s, "PSCI_FEATURES(%s) error (%d)\n", psci_fn_ids[i].name, feature); > >>>>> + else > >>>>> + seq_printf(s, "%s is supported\n", psci_fn_ids[i].name); > >>>>> + } > >>>>> + > >>>>> + return 0; > >>>>> +} > >>>>> + > >>>>> +static int psci_debugfs_open(struct inode *inode, struct file *f) > >>>>> +{ > >>>>> + return single_open(f, psci_debugfs_read, NULL); > >>>>> +} > >>>>> + > >>>>> +static const struct file_operations psci_debugfs_ops = { > >>>>> + .owner = THIS_MODULE, > >>>>> + .open = psci_debugfs_open, > >>>>> + .release = single_release, > >>>>> + .read = seq_read, > >>>>> + .llseek = seq_lseek > >>>>> +}; > >>>>> + > >>>>> +static int __init psci_debugfs_init(void) > >>>>> +{ > >>>>> + return PTR_ERR_OR_ZERO(debugfs_create_file("psci", S_IRUGO, NULL, NULL, > >>>>> + &psci_debugfs_ops)); > >>>>> +} > >>>>> +late_initcall(psci_debugfs_init) > >>>>> +#endif > >>>>> + > >>>>> #ifdef CONFIG_CPU_IDLE > >>>>> static int psci_suspend_finisher(unsigned long state) > >>>>> { > >>>>> diff --git a/include/uapi/linux/psci.h b/include/uapi/linux/psci.h > >>>>> index 2bf93c0d6354..f6f0bad5858b 100644 > >>>>> --- a/include/uapi/linux/psci.h > >>>>> +++ b/include/uapi/linux/psci.h > >>>>> @@ -48,11 +48,20 @@ > >>>>> #define PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU PSCI_0_2_FN64(7) > >>>>> > >>>>> #define PSCI_1_0_FN_PSCI_FEATURES PSCI_0_2_FN(10) > >>>>> +#define PSCI_1_0_FN_CPU_FREEZE PSCI_0_2_FN(11) > >>>>> +#define PSCI_1_0_FN_CPU_DEFAULT_SUSPEND PSCI_0_2_FN(12) > >>>>> +#define PSCI_1_0_FN_NODE_HW_STATE PSCI_0_2_FN(13) > >>>>> #define PSCI_1_0_FN_SYSTEM_SUSPEND PSCI_0_2_FN(14) > >>>>> #define PSCI_1_0_FN_SET_SUSPEND_MODE PSCI_0_2_FN(15) > >>>>> +#define PSCI_1_0_FN_STAT_RESIDENCY PSCI_0_2_FN(16) > >>>>> +#define PSCI_1_0_FN_STAT_COUNT PSCI_0_2_FN(17) > >>>>> #define PSCI_1_1_FN_SYSTEM_RESET2 PSCI_0_2_FN(18) > >>>>> > >>>>> +#define PSCI_1_0_FN64_CPU_DEFAULT_SUSPEND PSCI_0_2_FN64(12) > >>>>> +#define PSCI_1_0_FN64_NODE_HW_STATE PSCI_0_2_FN64(13) > >>>>> #define PSCI_1_0_FN64_SYSTEM_SUSPEND PSCI_0_2_FN64(14) > >>>>> +#define PSCI_1_0_FN64_STAT_RESIDENCY PSCI_0_2_FN64(16) > >>>>> +#define PSCI_1_0_FN64_STAT_COUNT PSCI_0_2_FN64(17) > >>>>> #define PSCI_1_1_FN64_SYSTEM_RESET2 PSCI_0_2_FN64(18) > >>>>> > >>>>> /* PSCI v0.2 power state encoding for CPU_SUSPEND function */ > >>> > >>> > >>> > > > > > > -- With best wishes Dmitry _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel