[BISECTED] Was Re: acpi/suspend - irq 9: nobody cared

[Bob Copeland <me@bobcopeland.com>]

On Tue, May 12, 2009 at 01:01:06PM -0600, Bjorn Helgaas wrote:
> Even if you can't bisect this, can you please open a bugzilla at
> http://bugzilla.kernel.org? 

Done: http://bugzilla.kernel.org/show_bug.cgi?id=13289

I have bisected it.  I don't know if it's related, but I have a 
"MacBook 1,1" which in sleep.c has a quirk related to SCI_EN, and I
see that this patch changed ACPI_PM1_CONTROL_PRESERVED_BITS to include
SCI_EN.  I have verified that reverting the patch on top of latest -rc
prevents irq 9 from being disabled.

commit 20869dcfde204e1c21b642608d708d82472fee2b
Author: Bob Moore <robert.moore@intel.com>
Date:   Fri Mar 13 09:10:46 2009 +0800

    ACPICA: Preserve all PM control reserved and ignored bits
    
    As per the ACPI specification, preserve (read/modify/write) all
    bits that are defined as either reserved or ignored (PM control
    control registers only.)
    
    Signed-off-by: Bob Moore <robert.moore@intel.com>
    Signed-off-by: Lin Ming <ming.m.lin@intel.com>
    Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/acpica/aclocal.h b/drivers/acpi/acpica/aclocal.h
index 18a8d96..f01e155 100644
--- a/drivers/acpi/acpica/aclocal.h
+++ b/drivers/acpi/acpica/aclocal.h
@@ -780,7 +780,15 @@ struct acpi_bit_register_info {
  * must be preserved.
  */
 #define ACPI_PM1_STATUS_PRESERVED_BITS          0x0800	/* Bit 11 */
-#define ACPI_PM1_CONTROL_PRESERVED_BITS         0x0200	/* Bit 9 (whatever) */
+
+/* For control registers, both ignored and reserved bits must be preserved */
+
+#define ACPI_PM1_CONTROL_IGNORED_BITS           0x0201	/* Bits 9, 0(SCI_EN) */
+#define ACPI_PM1_CONTROL_RESERVED_BITS          0xC1F8	/* Bits 14-15, 3-8 */
+#define ACPI_PM1_CONTROL_PRESERVED_BITS \
+	       (ACPI_PM1_CONTROL_IGNORED_BITS | ACPI_PM1_CONTROL_RESERVED_BITS)
+
+#define ACPI_PM2_CONTROL_PRESERVED_BITS         0xFFFFFFFE	/* All except bit 0 */
 
 /*
  * Register IDs
diff --git a/drivers/acpi/acpica/hwregs.c b/drivers/acpi/acpica/hwregs.c
index fd7abe2..6117362 100644
--- a/drivers/acpi/acpica/hwregs.c
+++ b/drivers/acpi/acpica/hwregs.c
@@ -328,6 +328,21 @@ acpi_status acpi_hw_register_write(u32 register_id, u32 value)
 
 	case ACPI_REGISTER_PM2_CONTROL:	/* 8-bit access */
 
+		/*
+		 * For control registers, all reserved bits must be preserved,
+		 * as per the ACPI spec.
+		 */
+		status =
+		    acpi_read(&read_value, &acpi_gbl_FADT.xpm2_control_block);
+		if (ACPI_FAILURE(status)) {
+			goto exit;
+		}
+
+		/* Insert the bits to be preserved */
+
+		ACPI_INSERT_BITS(value, ACPI_PM2_CONTROL_PRESERVED_BITS,
+				 read_value);
+
 		status = acpi_write(value, &acpi_gbl_FADT.xpm2_control_block);
 		break;
 


-- 
Bob Copeland %% www.bobcopeland.com