Commit e38e8a07 authored by Bob Moore's avatar Bob Moore Committed by Andi Kleen
Browse files

Make GPE disable more robust 

Implemented another change for the GPE disable. We now perform a
read-change-write of the enable register instead of simply writing out the
cached enable mask. This will prevent inadvertent enabling of GPEs if a rogue
GPE is received during initialization (before GPE handlers are installed.)

http://bugzilla.kernel.org/show_bug.cgi?id=6217



Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
Signed-off-by: default avatarLin Ming <ming.m.lin@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
parent 87dc5e32

drivers/acpi/events/evgpe.c

+14 −4
Original line number Diff line number Diff line
@@ -256,7 +256,7 @@ acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info) 
		return_ACPI_STATUS(status);

	}



	/* Mark wake-disabled or HW disable, or both */

	/* Clear the appropriate enabled flags for this GPE */



	switch (gpe_event_info->flags & ACPI_GPE_TYPE_MASK) {

	case ACPI_GPE_TYPE_WAKE:
@@ -273,13 +273,23 @@ acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info) 
		/* Disable the requested runtime GPE */



		ACPI_CLEAR_BIT(gpe_event_info->flags, ACPI_GPE_RUN_ENABLED);



		/* fallthrough */

		break;



	default:

		acpi_hw_write_gpe_enable_reg(gpe_event_info);

		break;

	}



	/*

	 * Even if we don't know the GPE type, make sure that we always

	 * disable it. low_disable_gpe will just clear the enable bit for this

	 * GPE and write it. It will not write out the current GPE enable mask,

	 * since this may inadvertently enable GPEs too early, if a rogue GPE has

	 * come in during ACPICA initialization - possibly as a result of AML or

	 * other code that has enabled the GPE.

	 */

	status = acpi_hw_low_disable_gpe(gpe_event_info);

	return_ACPI_STATUS(status);



	return_ACPI_STATUS(AE_OK);

}

drivers/acpi/hardware/hwgpe.c

+49 −1
Original line number Diff line number Diff line
@@ -53,6 +53,54 @@ static acpi_status 
acpi_hw_enable_wakeup_gpe_block(struct acpi_gpe_xrupt_info *gpe_xrupt_info,

				struct acpi_gpe_block_info *gpe_block);



/******************************************************************************

 *

 * FUNCTION:	acpi_hw_low_disable_gpe

 *

 * PARAMETERS:	gpe_event_info	    - Info block for the GPE to be disabled

 *

 * RETURN:	Status

 *

 * DESCRIPTION: Disable a single GPE in the enable register.

 *

 ******************************************************************************/



acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)

{

	struct acpi_gpe_register_info *gpe_register_info;

	acpi_status status;

	u32 enable_mask;



	/* Get the info block for the entire GPE register */



	gpe_register_info = gpe_event_info->register_info;

	if (!gpe_register_info) {

		return (AE_NOT_EXIST);

	}



	/* Get current value of the enable register that contains this GPE */



	status = acpi_hw_low_level_read(ACPI_GPE_REGISTER_WIDTH, &enable_mask,

					&gpe_register_info->enable_address);

	if (ACPI_FAILURE(status)) {

		return (status);

	}



	/* Clear just the bit that corresponds to this GPE */



	ACPI_CLEAR_BIT(enable_mask,

		       ((u32) 1 <<

			(gpe_event_info->gpe_number -

			 gpe_register_info->base_gpe_number)));



	/* Write the updated enable mask */



	status = acpi_hw_low_level_write(ACPI_GPE_REGISTER_WIDTH, enable_mask,

					 &gpe_register_info->enable_address);



	return (status);

}



/******************************************************************************

 *

 * FUNCTION:    acpi_hw_write_gpe_enable_reg

include/acpi/achware.h

+2 −0
Original line number Diff line number Diff line
@@ -87,6 +87,8 @@ acpi_status acpi_hw_clear_acpi_status(void); 
/*

 * hwgpe - GPE support

 */

acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info);



acpi_status

acpi_hw_write_gpe_enable_reg(struct acpi_gpe_event_info *gpe_event_info);

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