diff options
author | Daniel Drake <drake@endlessm.com> | 2018-09-27 15:47:33 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-13 09:18:54 +0200 |
commit | 4c4cad25a9a6056a8d67a8f06d431f89fcc179b4 (patch) | |
tree | 1c5c3accdd87010f81facae127e77f83eff89cbe /drivers/pci | |
parent | 1bdd5e26bf24e0d8228d722e6e2af3e1c2340f32 (diff) |
PCI: Reprogram bridge prefetch registers on resume
commit 083874549fdfefa629dfa752785e20427dde1511 upstream.
On 38+ Intel-based ASUS products, the NVIDIA GPU becomes unusable after S3
suspend/resume. The affected products include multiple generations of
NVIDIA GPUs and Intel SoCs. After resume, nouveau logs many errors such
as:
fifo: fault 00 [READ] at 0000005555555000 engine 00 [GR] client 04
[HUB/FE] reason 4a [] on channel -1 [007fa91000 unknown]
DRM: failed to idle channel 0 [DRM]
Similarly, the NVIDIA proprietary driver also fails after resume (black
screen, 100% CPU usage in Xorg process). We shipped a sample to NVIDIA for
diagnosis, and their response indicated that it's a problem with the parent
PCI bridge (on the Intel SoC), not the GPU.
Runtime suspend/resume works fine, only S3 suspend is affected.
We found a workaround: on resume, rewrite the Intel PCI bridge
'Prefetchable Base Upper 32 Bits' register (PCI_PREF_BASE_UPPER32). In the
cases that I checked, this register has value 0 and we just have to rewrite
that value.
Linux already saves and restores PCI config space during suspend/resume,
but this register was being skipped because upon resume, it already has
value 0 (the correct, pre-suspend value).
Intel appear to have previously acknowledged this behaviour and the
requirement to rewrite this register:
https://bugzilla.kernel.org/show_bug.cgi?id=116851#c23
Based on that, rewrite the prefetch register values even when that appears
unnecessary.
We have confirmed this solution on all the affected models we have in-hands
(X542UQ, UX533FD, X530UN, V272UN).
Additionally, this solves an issue where r8169 MSI-X interrupts were broken
after S3 suspend/resume on ASUS X441UAR. This issue was recently worked
around in commit 7bb05b85bc2d ("r8169: don't use MSI-X on RTL8106e"). It
also fixes the same issue on RTL6186evl/8111evl on an Aimfor-tech laptop
that we had not yet patched. I suspect it will also fix the issue that was
worked around in commit 7c53a722459c ("r8169: don't use MSI-X on
RTL8168g").
Thomas Martitz reports that this change also solves an issue where the AMD
Radeon Polaris 10 GPU on the HP Zbook 14u G5 is unresponsive after S3
suspend/resume.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=201069
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-By: Peter Wu <peter@lekensteyn.nl>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/pci.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6b3c5c4cbb37..ccbbd4cde0f1 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1114,12 +1114,12 @@ int pci_save_state(struct pci_dev *dev) EXPORT_SYMBOL(pci_save_state); static void pci_restore_config_dword(struct pci_dev *pdev, int offset, - u32 saved_val, int retry) + u32 saved_val, int retry, bool force) { u32 val; pci_read_config_dword(pdev, offset, &val); - if (val == saved_val) + if (!force && val == saved_val) return; for (;;) { @@ -1138,25 +1138,36 @@ static void pci_restore_config_dword(struct pci_dev *pdev, int offset, } static void pci_restore_config_space_range(struct pci_dev *pdev, - int start, int end, int retry) + int start, int end, int retry, + bool force) { int index; for (index = end; index >= start; index--) pci_restore_config_dword(pdev, 4 * index, pdev->saved_config_space[index], - retry); + retry, force); } static void pci_restore_config_space(struct pci_dev *pdev) { if (pdev->hdr_type == PCI_HEADER_TYPE_NORMAL) { - pci_restore_config_space_range(pdev, 10, 15, 0); + pci_restore_config_space_range(pdev, 10, 15, 0, false); /* Restore BARs before the command register. */ - pci_restore_config_space_range(pdev, 4, 9, 10); - pci_restore_config_space_range(pdev, 0, 3, 0); + pci_restore_config_space_range(pdev, 4, 9, 10, false); + pci_restore_config_space_range(pdev, 0, 3, 0, false); + } else if (pdev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { + pci_restore_config_space_range(pdev, 12, 15, 0, false); + + /* + * Force rewriting of prefetch registers to avoid S3 resume + * issues on Intel PCI bridges that occur when these + * registers are not explicitly written. + */ + pci_restore_config_space_range(pdev, 9, 11, 0, true); + pci_restore_config_space_range(pdev, 0, 8, 0, false); } else { - pci_restore_config_space_range(pdev, 0, 15, 0); + pci_restore_config_space_range(pdev, 0, 15, 0, false); } } |