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PCI/ACPI: Check for _OSC support in acpi_pci_osc_control_set()

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Get rid of acpi_pci_osc_support() and check for _OSC supported features
directly in acpi_pci_osc_control_set(). There is no point in doing an
unconditional _OSC query with control=0 even when the kernel later wants to
take control over more features.

This saves one _OSC query and simplifies the code by getting rid of the
acpi_pci_osc_support() function. As a side effect, the !control checks in
acpi_pci_query_osc() can also be removed.

Link: https://lore.kernel.org/r/20210824122054.29481-5-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
This commit is contained in:
Joerg Roedel 2021-08-24 14:20:54 +02:00 committed by Bjorn Helgaas
parent 87f1f87a16
commit 6bc779ee05
1 changed files with 32 additions and 49 deletions
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81
drivers/acpi/pci_root.c
View File

@ -203,26 +203,16 @@ static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root,
capbuf[OSC_QUERY_DWORD] = OSC_QUERY_ENABLE;
capbuf[OSC_SUPPORT_DWORD] = support;
if (control)
capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
else
/* Run _OSC query only with existing controls. */
capbuf[OSC_CONTROL_DWORD] = root->osc_control_set;
capbuf[OSC_CONTROL_DWORD] = *control | root->osc_control_set;
status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
if (ACPI_SUCCESS(status)) {
root->osc_support_set = support;
if (control)
*control = result;
*control = result;
}
return status;
}
static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
{
return acpi_pci_query_osc(root, flags, NULL);
}
struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
{
struct acpi_pci_root *root;
@ -345,8 +335,9 @@ EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
* _OSC bits the BIOS has granted control of, but its contents are meaningless
* on failure.
**/
static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 req)
static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 support)
{
u32 req = OSC_PCI_EXPRESS_CAPABILITY_CONTROL;
struct acpi_pci_root *root;
acpi_status status;
u32 ctrl, capbuf[3];
@ -354,22 +345,16 @@ static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 r
if (!mask)
return AE_BAD_PARAMETER;
ctrl = *mask;
if ((ctrl & req) != req)
return AE_TYPE;
root = acpi_pci_find_root(handle);
if (!root)
return AE_NOT_EXIST;
*mask = ctrl | root->osc_control_set;
/* No need to evaluate _OSC if the control was already granted. */
if ((root->osc_control_set & ctrl) == ctrl)
return AE_OK;
ctrl = *mask;
*mask |= root->osc_control_set;
/* Need to check the available controls bits before requesting them. */
while (*mask) {
status = acpi_pci_query_osc(root, root->osc_support_set, mask);
do {
status = acpi_pci_query_osc(root, support, mask);
if (ACPI_FAILURE(status))
return status;
if (ctrl == *mask)
@ -377,7 +362,11 @@ static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 r
decode_osc_control(root, "platform does not support",
ctrl & ~(*mask));
ctrl = *mask;
}
} while (*mask);
/* No need to request _OSC if the control was already granted. */
if ((root->osc_control_set & ctrl) == ctrl)
return AE_OK;
if ((ctrl & req) != req) {
decode_osc_control(root, "not requesting control; platform does not support",
@ -470,7 +459,7 @@ static bool os_control_query_checks(struct acpi_pci_root *root, u32 support)
static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
bool is_pcie)
{
u32 support, control, requested;
u32 support, control = 0, requested = 0;
acpi_status status;
struct acpi_device *device = root->device;
acpi_handle handle = device->handle;
@ -490,28 +479,15 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
support = calculate_support();
decode_osc_support(root, "OS supports", support);
status = acpi_pci_osc_support(root, support);
if (ACPI_FAILURE(status)) {
*no_aspm = 1;
/* _OSC is optional for PCI host bridges */
if ((status == AE_NOT_FOUND) && !is_pcie)
return;
if (os_control_query_checks(root, support))
requested = control = calculate_control();
dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
acpi_format_exception(status));
return;
}
if (!os_control_query_checks(root, support))
return;
requested = control = calculate_control();
status = acpi_pci_osc_control_set(handle, &control,
OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
status = acpi_pci_osc_control_set(handle, &control, support);
if (ACPI_SUCCESS(status)) {
decode_osc_control(root, "OS now controls", control);
if (control)
decode_osc_control(root, "OS now controls", control);
if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
/*
* We have ASPM control, but the FADT indicates that
@ -522,11 +498,6 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
*no_aspm = 1;
}
} else {
decode_osc_control(root, "OS requested", requested);
decode_osc_control(root, "platform willing to grant", control);
dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
acpi_format_exception(status));
/*
* We want to disable ASPM here, but aspm_disabled
* needs to remain in its state from boot so that we
@ -535,6 +506,18 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
* root scan.
*/
*no_aspm = 1;
/* _OSC is optional for PCI host bridges */
if ((status == AE_NOT_FOUND) && !is_pcie)
return;
if (control) {
decode_osc_control(root, "OS requested", requested);
decode_osc_control(root, "platform willing to grant", control);
}
dev_info(&device->dev, "_OSC: platform retains control of PCIe features (%s)\n",
acpi_format_exception(status));
}
}