In APEI firmware first mode, hardware error is reported by hardware to firmware firstly, then firmware reports the error to Linux in a GHES error record via POLL/SCI/IRQ/NMI etc. This may result in some issues if OS has no full APEI support. So some firmware implementation will work in a back-compatible mode by default. Where firmware will only notify OS in old-fashion, without GHES record. For example, for a fatal hardware error, only NMI is signaled, no GHES record. To gain full APEI power on these machines, a special APEI _OSC needs to be evaluated to tell firmware that Linux has full APEI support. This patch add the APEI _OSC support. Signed-off-by: Huang Ying <ying.huang@xxxxxxxxx> --- drivers/acpi/apei/apei-base.c | 42 ++++++++++++++++++++++++++++++++++++++ drivers/acpi/apei/apei-internal.h | 2 + drivers/acpi/apei/ghes.c | 8 +++++++ 3 files changed, 52 insertions(+) --- a/drivers/acpi/apei/apei-base.c +++ b/drivers/acpi/apei/apei-base.c @@ -603,3 +603,45 @@ struct dentry *apei_get_debugfs_dir(void return dapei; } EXPORT_SYMBOL_GPL(apei_get_debugfs_dir); + +enum { + APEI_OSC_SETUP_UNKNOWN, + APEI_OSC_SETUP_FAILED, + APEI_OSC_SETUP_SUCCEEDED, +}; + +int apei_osc_setup(void) +{ + /* Prevent _OSC to be evaluated simultaneously */ + static DEFINE_MUTEX(mutex); + static int status = APEI_OSC_SETUP_UNKNOWN; + static u8 apei_uuid_str[] = "ed855e0c-6c90-47bf-a62a-26de0fc5ad5c"; + acpi_handle handle; + u32 capbuf[3]; + struct acpi_osc_context context = { + .uuid_str = apei_uuid_str, + .rev = 1, + .cap.length = sizeof(capbuf), + .cap.pointer = capbuf, + }; + + mutex_lock(&mutex); + if (status == APEI_OSC_SETUP_UNKNOWN) { + capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE; + capbuf[OSC_SUPPORT_TYPE] = 0; + capbuf[OSC_CONTROL_TYPE] = 0; + + if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)) + || ACPI_FAILURE(acpi_run_osc(handle, &context))) { + pr_err(APEI_PFX "APEI _OSC failed!\n"); + status = APEI_OSC_SETUP_FAILED; + } else { + kfree(context.ret.pointer); + status = APEI_OSC_SETUP_SUCCEEDED; + } + } + mutex_unlock(&mutex); + + return status == APEI_OSC_SETUP_SUCCEEDED ? 0 : -EIO; +} +EXPORT_SYMBOL_GPL(apei_osc_setup); --- a/drivers/acpi/apei/apei-internal.h +++ b/drivers/acpi/apei/apei-internal.h @@ -113,4 +113,6 @@ void apei_estatus_print(const char *pfx, const struct acpi_hest_generic_status *estatus); int apei_estatus_check_header(const struct acpi_hest_generic_status *estatus); int apei_estatus_check(const struct acpi_hest_generic_status *estatus); + +int apei_osc_setup(void); #endif --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -687,6 +687,8 @@ static unsigned long ghes_esource_preall return prealloc_size; } +static int ghes_remove(struct platform_device *ghes_dev); + static int __devinit ghes_probe(struct platform_device *ghes_dev) { struct acpi_hest_generic *generic; @@ -770,6 +772,12 @@ static int __devinit ghes_probe(struct p } platform_set_drvdata(ghes_dev, ghes); + rc = apei_osc_setup(); + if (rc) { + ghes_remove(ghes_dev); + return rc; + } + return 0; err: if (ghes) { -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html