From dc332fdf9f373a87b1e2f423b5b004b2a3c37e1a Mon Sep 17 00:00:00 2001 From: Jonathan Nieder Date: Sun, 8 Jul 2012 21:55:14 +0200 Subject: [PATCH] ACPI / PM: Leave Bus Master Arbitration enabled for suspend/resume This is an old suspend/resume lockup fix: commit 2780cc4660e1 Author: Len Brown Date: Thu Dec 23 13:43:30 2004 -0500 [ACPI] Fix suspend/resume lockup issue by leaving Bus Master Arbitration enabled. The ACPI spec mandates it be disabled only for C3. http://bugzilla.kernel.org/show_bug.cgi?id=3599 Signed-off-by: David Shaohua Li Signed-off-by: Len Brown The bug snuck back in in commit 2feec47d4c5f (ACPICA: ACPI 5: Support for new FADT SleepStatus, SleepControl registers, 2012-02-14), presumably by copy/pasting a copy of the code without that fix for the legacy case. On affected machines, after that commit, the machine locks up hard on resume from suspend. The same fix as seven years ago still works. Addresses . Reported-bisected-and-tested-by: Octavio Alvarez Reported-by: Adrian Knoth Signed-off-by: Jonathan Nieder Cc: stable@vger.kernel.org Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/hwsleep.c | 22 ---------------------- 1 file changed, 22 deletions(-) diff --git a/drivers/acpi/acpica/hwsleep.c b/drivers/acpi/acpica/hwsleep.c index 0ed85cac3231..615996a36bed 100644 --- a/drivers/acpi/acpica/hwsleep.c +++ b/drivers/acpi/acpica/hwsleep.c @@ -95,18 +95,6 @@ acpi_status acpi_hw_legacy_sleep(u8 sleep_state, u8 flags) return_ACPI_STATUS(status); } - if (sleep_state != ACPI_STATE_S5) { - /* - * Disable BM arbitration. This feature is contained within an - * optional register (PM2 Control), so ignore a BAD_ADDRESS - * exception. - */ - status = acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); - if (ACPI_FAILURE(status) && (status != AE_BAD_ADDRESS)) { - return_ACPI_STATUS(status); - } - } - /* * 1) Disable/Clear all GPEs * 2) Enable all wakeup GPEs @@ -364,16 +352,6 @@ acpi_status acpi_hw_legacy_wake(u8 sleep_state, u8 flags) [ACPI_EVENT_POWER_BUTTON]. status_register_id, ACPI_CLEAR_STATUS); - /* - * Enable BM arbitration. This feature is contained within an - * optional register (PM2 Control), so ignore a BAD_ADDRESS - * exception. - */ - status = acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); - if (ACPI_FAILURE(status) && (status != AE_BAD_ADDRESS)) { - return_ACPI_STATUS(status); - } - acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING); return_ACPI_STATUS(status); } -- 2.39.5