14e4:16bc SD card slot not working on Acer Aspire One 756

14e4:16bc SD card slot not working on Acer Aspire One 756

[Stefan Frings]

 14e4:16bc SD card slot not working on Acer Aspire One 756

 The memory card read (Broadcaom BCM57765) does not work on Aver Aspire 
 One 756 because Linux enabled ASPM L1 on the PCIe channel since a 
 related change in Kernel 3.0.20. Please change the code so that only 
 APSN L0s is enabled on that machine on the PCIe channel 00:1c.2.

 Until a solution is available, I use the following command as a 
 workaround: sudo setpci -s 00:1c.2 0x50.B=0x41

 Description of the change that introduced the problem: 
 https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=6cac12dfab9c57a4f76821412224b226a9b08dff

 The full problem description with log files and result of my bisecting 
 can be found in the Ubuntu Bug L#1178131.

 Link to the Ubuntu Bug report: 
 https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1178131

 The problem is still present in Kernel 3.10-rc1, rc2 and rc3.
 Kernels before 3.0.20 are NOT affected by the problem.
 The first problematic Linux version is 3.0.20.

 Steps to reproduce:

 - Boot Linux with any Kernel after 3.0.19 (Using Gnome 3 Desktop)
 - Insert any memory card into the card reader
 - Problem: nothing happens
 - Problem: In dmesg, the mmc driver reports communication timeouts for 
 the card reader
 - Remove the memory card
 - Enter sudo setpci -s 00:1c.2 0x50.B=0x41 (This disables ASPM L1)
 - Insert the memory card
 - Result: It gets detected immediately. Gnome pop-ups a related 
 notification window.
 - Remove the memory card
 - Enter sudo setpci -s 00:1c.2 0x50.B=0x43 (this is the value that the 
 Linux Kernel sets during boot)
 - Insert the memory card
 - Problem: The card is not detected

-- 
 Stefan Frings
 Markenstraße 12
 40227 Düsseldorf

Re: 14e4:16bc SD card slot not working on Acer Aspire One 756

[Yijing Wang]

[-- Attachment #1: Type: text/plain, Size: 2264 bytes --]

According to boot dmesg.
We found "ACPI FADT declares the system doesn't support PCIe ASPM, so disable it", so FADT dictate no aspm support in this platform.
Matthew pcie_clear_aspm() to acpi_pci_root_add() when acpi_pci_osc_control_set() return success.
Unfortunately in your machine, acpi_pci_osc_control_set() return failed, so system missing the pcie_clear_aspm();
So we should move pci_clear_aspm() out of ACPI_SUCCESS() check.

Stefan, can you help test the attached patch in 3.10-rcx?

Thanks!
Yijing.

On 2013/5/28 13:21, Stefan Frings wrote:
> 14e4:16bc SD card slot not working on Acer Aspire One 756
> 
> The memory card read (Broadcaom BCM57765) does not work on Aver Aspire One 756 because Linux enabled ASPM L1 on the PCIe channel since a related change in Kernel 3.0.20. Please change the code so that only APSN L0s is enabled on that machine on the PCIe channel 00:1c.2.
> 
> Until a solution is available, I use the following command as a workaround: sudo setpci -s 00:1c.2 0x50.B=0x41
> 
> Description of the change that introduced the problem: https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/commit/?id=6cac12dfab9c57a4f76821412224b226a9b08dff
> 
> The full problem description with log files and result of my bisecting can be found in the Ubuntu Bug L#1178131.
> 
> Link to the Ubuntu Bug report: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1178131
> 
> The problem is still present in Kernel 3.10-rc1, rc2 and rc3.
> Kernels before 3.0.20 are NOT affected by the problem.
> The first problematic Linux version is 3.0.20.
> 
> Steps to reproduce:
> 
> - Boot Linux with any Kernel after 3.0.19 (Using Gnome 3 Desktop)
> - Insert any memory card into the card reader
> - Problem: nothing happens
> - Problem: In dmesg, the mmc driver reports communication timeouts for the card reader
> - Remove the memory card
> - Enter sudo setpci -s 00:1c.2 0x50.B=0x41 (This disables ASPM L1)
> - Insert the memory card
> - Result: It gets detected immediately. Gnome pop-ups a related notification window.
> - Remove the memory card
> - Enter sudo setpci -s 00:1c.2 0x50.B=0x43 (this is the value that the Linux Kernel sets during boot)
> - Insert the memory card
> - Problem: The card is not detected
> 


-- 
Thanks!
Yijing

[-- Attachment #2: 0001-PCI-move-pcie_clear_aspm-out-of-ACPI_SUCCESS-checkin.patch --]
[-- Type: text/x-patch, Size: 1637 bytes --]

>From deec1ca8eb80cea58beadb1404abb163426956f3 Mon Sep 17 00:00:00 2001
From: Yijing Wang <wangyijing@huawei.com>
Date: Tue, 28 May 2013 16:02:55 +0800
Subject: [PATCH] PCI: move pcie_clear_aspm() out of ACPI_SUCCESS() checking

We should move pcie_clear_aspm() out of ACPI_SUCCESS() checking
in acpi_pci_root_add(), because if FADT dictate no aspm support,
and acpi_pci_osc_control_set() get _OSC control fail. We will
miss aspm clear here.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
---
 drivers/acpi/pci_root.c |   14 +++++++-------
 1 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index f6c0998..632c6e3 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -506,13 +506,6 @@ static int acpi_pci_root_add(struct acpi_device *device,
 		if (ACPI_SUCCESS(status)) {
 			dev_info(&device->dev,
 				"ACPI _OSC control (0x%02x) granted\n", flags);
-			if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
-				/*
-				 * We have ASPM control, but the FADT indicates
-				 * that it's unsupported. Clear it.
-				 */
-				pcie_clear_aspm(root->bus);
-			}
 		} else {
 			dev_info(&device->dev,
 				"ACPI _OSC request failed (%s), "
@@ -522,6 +515,13 @@ static int acpi_pci_root_add(struct acpi_device *device,
 				"disabling ASPM\n");
 			pcie_no_aspm();
 		}
+		if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
+			/*
+			 * We have ASPM control, but the FADT indicates
+			 * that it's unsupported. Clear it.
+			 */
+			pcie_clear_aspm(root->bus);
+		}
 	} else {
 		dev_info(&device->dev,
 			 "Unable to request _OSC control "
-- 
1.7.1