From: Sinan Kaya <okaya@kernel.org>
To: linux-pci@vger.kernel.org
Cc: Sinan Kaya <okaya@kernel.org>,
Bjorn Helgaas <bhelgaas@google.com>,
"Rafael J. Wysocki" <rjw@rjwysocki.net>,
Len Brown <lenb@kernel.org>,
linux-acpi@vger.kernel.org (open list:ACPI),
linux-kernel@vger.kernel.org (open list)
Subject: [PATCH 2/2] PCI/ACPI: allow _OSC presence to be optional for PCI
Date: Thu, 9 Aug 2018 18:46:23 +0000 [thread overview]
Message-ID: <1533840383-7841-2-git-send-email-okaya@kernel.org> (raw)
In-Reply-To: <1533840383-7841-1-git-send-email-okaya@kernel.org>
ACPI Spec 6.0 Section 6.2.11.3 OSC Implementation Example for PCI
Host Bridge Devices:
For a host bridge device that originates a PCI Express hierarchy,
the _OSC interface defined in this section is required.
For a host bridge device that originates a PCI/PCI-X bus hierarchy,
inclusion of an _OSC object is optional.
Allow PCI host bridges to bail out silently if _OSC is not found.
Signed-off-by: Sinan Kaya <okaya@kernel.org>
Reported-by: Michael Kelley <mikelley@microsoft.com>
---
drivers/acpi/pci_root.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 9d738e2..c94ed01 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -421,7 +421,8 @@ acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
}
EXPORT_SYMBOL(acpi_pci_osc_control_set);
-static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
+static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
+ bool is_pcie)
{
u32 support, control, requested;
acpi_status status;
@@ -460,9 +461,14 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
if (pcie_aspm_support_enabled())
aspm_msg = "; disabling ASPM";
- dev_info(&device->dev, "_OSC failed (%s) %s\n",
- acpi_format_exception(status), aspm_msg);
*no_aspm = 1;
+
+ /* _OSC is optional for PCI host bridges */
+ if ((status == AE_NOT_FOUND) && !is_pcie)
+ return;
+
+ dev_info(&device->dev, "_OSC failed (%s) %s\n",
+ acpi_format_exception(status), aspm_msg);
return;
}
@@ -538,6 +544,7 @@ static int acpi_pci_root_add(struct acpi_device *device,
acpi_handle handle = device->handle;
int no_aspm = 0;
bool hotadd = system_state == SYSTEM_RUNNING;
+ bool is_pcie;
root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
if (!root)
@@ -595,7 +602,8 @@ static int acpi_pci_root_add(struct acpi_device *device,
root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
- negotiate_os_control(root, &no_aspm);
+ is_pcie = strcmp(acpi_device_hid(device), "PNP0A08") == 0;
+ negotiate_os_control(root, &no_aspm, is_pcie);
/*
* TBD: Need PCI interface for enumeration/configuration of roots.
--
2.7.4
next prev parent reply other threads:[~2018-08-09 18:46 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-08-09 18:46 [PATCH 1/2] PCI/ACPI: correct error message for ASPM disabling Sinan Kaya
2018-08-09 18:46 ` Sinan Kaya [this message]
2018-08-10 0:27 ` Joe Perches
2018-08-10 2:15 ` Sinan Kaya
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1533840383-7841-2-git-send-email-okaya@kernel.org \
--to=okaya@kernel.org \
--cc=bhelgaas@google.com \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=rjw@rjwysocki.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).