ACPICA: Fix for resource descriptor optimization issues for _CRS/_SRC

Fixed a problem where resource descriptor size optimization
could cause a problem when a _CRS resource template is passed
to a _SRS method. The _SRS resource template must use the same
descriptors (with the same size) as returned from _CRS. This
change affects the following resource descriptors: IRQ/IRQNoFlags
and StartDependendentFn/StartDependentFnNoPri.

http://bugzilla.kernel.org/show_bug.cgi?id=9487

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 37 insertions, 2 deletions

diff --git a/drivers/acpi/resources/rsio.c b/drivers/acpi/resources/rsio.c
index b297bc3e4419..50f3acdd9c8e 100644
--- a/drivers/acpi/resources/rsio.c
+++ b/drivers/acpi/resources/rsio.c
@@ -185,7 +185,7 @@ struct acpi_rsconvert_info acpi_rs_convert_end_tag[2] = {
  *
  ******************************************************************************/
 
-struct acpi_rsconvert_info acpi_rs_get_start_dpf[5] = {
+struct acpi_rsconvert_info acpi_rs_get_start_dpf[6] = {
 	{ACPI_RSC_INITGET, ACPI_RESOURCE_TYPE_START_DEPENDENT,
 	 ACPI_RS_SIZE(struct acpi_resource_start_dependent),
 	 ACPI_RSC_TABLE_SIZE(acpi_rs_get_start_dpf)},
@@ -196,6 +196,12 @@ struct acpi_rsconvert_info acpi_rs_get_start_dpf[5] = {
 	 ACPI_ACCEPTABLE_CONFIGURATION,
 	 2},
 
+	/* Get the descriptor length (0 or 1 for Start Dpf descriptor) */
+
+	{ACPI_RSC_1BITFLAG, ACPI_RS_OFFSET(data.start_dpf.descriptor_length),
+	 AML_OFFSET(start_dpf.descriptor_type),
+	 0},
+
 	/* All done if there is no flag byte present in the descriptor */
 
 	{ACPI_RSC_EXIT_NE, ACPI_RSC_COMPARE_AML_LENGTH, 0, 1},
@@ -219,7 +225,9 @@ struct acpi_rsconvert_info acpi_rs_get_start_dpf[5] = {
  *
  ******************************************************************************/
 
-struct acpi_rsconvert_info acpi_rs_set_start_dpf[6] = {
+struct acpi_rsconvert_info acpi_rs_set_start_dpf[10] = {
+	/* Start with a default descriptor of length 1 */
+
 	{ACPI_RSC_INITSET, ACPI_RESOURCE_NAME_START_DEPENDENT,
 	 sizeof(struct aml_resource_start_dependent),
 	 ACPI_RSC_TABLE_SIZE(acpi_rs_set_start_dpf)},
@@ -236,6 +244,33 @@ struct acpi_rsconvert_info acpi_rs_set_start_dpf[6] = {
 	 AML_OFFSET(start_dpf.flags),
 	 2},
 	/*
+	 * All done if the output descriptor length is required to be 1
+	 * (i.e., optimization to 0 bytes cannot be attempted)
+	 */
+	{ACPI_RSC_EXIT_EQ, ACPI_RSC_COMPARE_VALUE,
+	 ACPI_RS_OFFSET(data.start_dpf.descriptor_length),
+	 1},
+
+	/* Set length to 0 bytes (no flags byte) */
+
+	{ACPI_RSC_LENGTH, 0, 0,
+	 sizeof(struct aml_resource_start_dependent_noprio)},
+
+	/*
+	 * All done if the output descriptor length is required to be 0.
+	 *
+	 * TBD: Perhaps we should check for error if input flags are not
+	 * compatible with a 0-byte descriptor.
+	 */
+	{ACPI_RSC_EXIT_EQ, ACPI_RSC_COMPARE_VALUE,
+	 ACPI_RS_OFFSET(data.start_dpf.descriptor_length),
+	 0},
+
+	/* Reset length to 1 byte (descriptor with flags byte) */
+
+	{ACPI_RSC_LENGTH, 0, 0, sizeof(struct aml_resource_irq)},
+
+	/*
 	 * All done if flags byte is necessary -- if either priority value
 	 * is not ACPI_ACCEPTABLE_CONFIGURATION
 	 */