On Sunday 07 of October 2012 21:00:09 Ondrej Zary wrote: > On Sunday 07 October 2012 15:13:27 Ondrej Zary wrote: > > Hello, > > Intel D845BG board comes out of S3 with PS/2 keyboard and mouse completely > > dead. The machine works otherwise (with USB keyboard or over network). When > > rebooted in this state, the BIOS hangs with blank screen. I have the latest > > BIOS installed (P08). > > > > Old kernels worked. Bisection pointed to commit: > > b6dacf63e9fb2e7a1369843d6cef332f76fca6a3 > > (ACPI: Unconditionally set SCI_EN on resume) > > > > Commenting out this line in drivers/acpi/sleep.c: > > acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1); > > fixes the problem. > > > > Any ideas why this breaks on this system? > > Added acpi_read_bit_register there and it seems that SCI_EN is already set! > > This patch fixes the problem here. I wonder how this affects systems that > require SCI_EN to be set. I'm not sure if reading SCI_EN is actually safe on all systems. Matthew, what do you think? Rafael > --- a/drivers/acpi/sleep.c > +++ b/drivers/acpi/sleep.c > @@ -271,6 +271,7 @@ static int acpi_suspend_enter(suspend_state_t pm_state) > acpi_status status = AE_OK; > u32 acpi_state = acpi_target_sleep_state; > int error; > + u32 sci_enabled; > > ACPI_FLUSH_CPU_CACHE(); > > @@ -289,7 +290,9 @@ static int acpi_suspend_enter(suspend_state_t pm_state) > } > > /* This violates the spec but is required for bug compatibility. */ > - acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1); > + acpi_read_bit_register(ACPI_BITREG_SCI_ENABLE, &sci_enabled); > + if (!sci_enabled) > + acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1); > > /* Reprogram control registers */ > acpi_leave_sleep_state_prep(acpi_state); > > -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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
