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author | Herbert Xu <herbert@gondor.apana.org.au> | 2017-01-12 16:10:00 +0800 |
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committer | Herbert Xu <herbert@gondor.apana.org.au> | 2017-01-12 16:10:00 +0800 |
commit | 4cf0662888026d5c1b62ed3fa8dc048a2ff2e124 (patch) | |
tree | a5c92c5024c599a00bfd8d402d2b7b0a619b0259 /drivers/acpi/sysfs.c | |
parent | c821f6ab2e47946f35ee2f30781c5185e5d07f65 (diff) | |
parent | a121103c922847ba5010819a3f250f1f7fc84ab8 (diff) | |
download | op-kernel-dev-4cf0662888026d5c1b62ed3fa8dc048a2ff2e124.zip op-kernel-dev-4cf0662888026d5c1b62ed3fa8dc048a2ff2e124.tar.gz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
Merging 4.10-rc3 so that the cryptodev tree builds on ARM64.
Diffstat (limited to 'drivers/acpi/sysfs.c')
-rw-r--r-- | drivers/acpi/sysfs.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index 703c26e..cf05ae9 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -708,6 +708,62 @@ end: return result ? result : size; } +/* + * A Quirk Mechanism for GPE Flooding Prevention: + * + * Quirks may be needed to prevent GPE flooding on a specific GPE. The + * flooding typically cannot be detected and automatically prevented by + * ACPI_GPE_DISPATCH_NONE check because there is a _Lxx/_Exx prepared in + * the AML tables. This normally indicates a feature gap in Linux, thus + * instead of providing endless quirk tables, we provide a boot parameter + * for those who want this quirk. For example, if the users want to prevent + * the GPE flooding for GPE 00, they need to specify the following boot + * parameter: + * acpi_mask_gpe=0x00 + * The masking status can be modified by the following runtime controlling + * interface: + * echo unmask > /sys/firmware/acpi/interrupts/gpe00 + */ + +/* + * Currently, the GPE flooding prevention only supports to mask the GPEs + * numbered from 00 to 7f. + */ +#define ACPI_MASKABLE_GPE_MAX 0x80 + +static u64 __initdata acpi_masked_gpes; + +static int __init acpi_gpe_set_masked_gpes(char *val) +{ + u8 gpe; + + if (kstrtou8(val, 0, &gpe) || gpe > ACPI_MASKABLE_GPE_MAX) + return -EINVAL; + acpi_masked_gpes |= ((u64)1<<gpe); + + return 1; +} +__setup("acpi_mask_gpe=", acpi_gpe_set_masked_gpes); + +void __init acpi_gpe_apply_masked_gpes(void) +{ + acpi_handle handle; + acpi_status status; + u8 gpe; + + for (gpe = 0; + gpe < min_t(u8, ACPI_MASKABLE_GPE_MAX, acpi_current_gpe_count); + gpe++) { + if (acpi_masked_gpes & ((u64)1<<gpe)) { + status = acpi_get_gpe_device(gpe, &handle); + if (ACPI_SUCCESS(status)) { + pr_info("Masking GPE 0x%x.\n", gpe); + (void)acpi_mask_gpe(handle, gpe, TRUE); + } + } + } +} + void acpi_irq_stats_init(void) { acpi_status status; |