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-rw-r--r--drivers/pci/pcie/Kconfig2
-rw-r--r--drivers/pci/pcie/aer_inject.c2
-rw-r--r--drivers/pci/pcie/aspm.c182
-rw-r--r--drivers/pci/pcie/edr.c28
4 files changed, 108 insertions, 106 deletions
diff --git a/drivers/pci/pcie/Kconfig b/drivers/pci/pcie/Kconfig
index 8999fcebde6a..17919b99fa66 100644
--- a/drivers/pci/pcie/Kconfig
+++ b/drivers/pci/pcie/Kconfig
@@ -47,7 +47,7 @@ config PCIEAER_INJECT
error injection can fake almost all kinds of errors with the
help of a user space helper tool aer-inject, which can be
gotten from:
- https://git.kernel.org/cgit/linux/kernel/git/gong.chen/aer-inject.git/
+ https://github.com/intel/aer-inject.git
config PCIEAER_CXL
bool "PCI Express CXL RAS support"
diff --git a/drivers/pci/pcie/aer_inject.c b/drivers/pci/pcie/aer_inject.c
index 2dab275d252f..f81b2303bf6a 100644
--- a/drivers/pci/pcie/aer_inject.c
+++ b/drivers/pci/pcie/aer_inject.c
@@ -6,7 +6,7 @@
* trigger various real hardware errors. Software based error
* injection can fake almost all kinds of errors with the help of a
* user space helper tool aer-inject, which can be gotten from:
- * https://git.kernel.org/cgit/linux/kernel/git/gong.chen/aer-inject.git/
+ * https://github.com/intel/aer-inject.git
*
* Copyright 2009 Intel Corporation.
* Huang Ying <ying.huang@intel.com>
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 2428d278e015..9cbdebb933ee 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -8,6 +8,8 @@
*/
#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/build_bug.h>
#include <linux/kernel.h>
#include <linux/limits.h>
#include <linux/math.h>
@@ -189,21 +191,18 @@ void pci_restore_aspm_l1ss_state(struct pci_dev *pdev)
#endif
#define MODULE_PARAM_PREFIX "pcie_aspm."
-/* Note: those are not register definitions */
-#define ASPM_STATE_L0S_UP (1) /* Upstream direction L0s state */
-#define ASPM_STATE_L0S_DW (2) /* Downstream direction L0s state */
-#define ASPM_STATE_L1 (4) /* L1 state */
-#define ASPM_STATE_L1_1 (8) /* ASPM L1.1 state */
-#define ASPM_STATE_L1_2 (0x10) /* ASPM L1.2 state */
-#define ASPM_STATE_L1_1_PCIPM (0x20) /* PCI PM L1.1 state */
-#define ASPM_STATE_L1_2_PCIPM (0x40) /* PCI PM L1.2 state */
-#define ASPM_STATE_L1_SS_PCIPM (ASPM_STATE_L1_1_PCIPM | ASPM_STATE_L1_2_PCIPM)
-#define ASPM_STATE_L1_2_MASK (ASPM_STATE_L1_2 | ASPM_STATE_L1_2_PCIPM)
-#define ASPM_STATE_L1SS (ASPM_STATE_L1_1 | ASPM_STATE_L1_1_PCIPM |\
- ASPM_STATE_L1_2_MASK)
-#define ASPM_STATE_L0S (ASPM_STATE_L0S_UP | ASPM_STATE_L0S_DW)
-#define ASPM_STATE_ALL (ASPM_STATE_L0S | ASPM_STATE_L1 | \
- ASPM_STATE_L1SS)
+/* Note: these are not register definitions */
+#define PCIE_LINK_STATE_L0S_UP BIT(0) /* Upstream direction L0s state */
+#define PCIE_LINK_STATE_L0S_DW BIT(1) /* Downstream direction L0s state */
+static_assert(PCIE_LINK_STATE_L0S == (PCIE_LINK_STATE_L0S_UP | PCIE_LINK_STATE_L0S_DW));
+
+#define PCIE_LINK_STATE_L1_SS_PCIPM (PCIE_LINK_STATE_L1_1_PCIPM |\
+ PCIE_LINK_STATE_L1_2_PCIPM)
+#define PCIE_LINK_STATE_L1_2_MASK (PCIE_LINK_STATE_L1_2 |\
+ PCIE_LINK_STATE_L1_2_PCIPM)
+#define PCIE_LINK_STATE_L1SS (PCIE_LINK_STATE_L1_1 |\
+ PCIE_LINK_STATE_L1_1_PCIPM |\
+ PCIE_LINK_STATE_L1_2_MASK)
struct pcie_link_state {
struct pci_dev *pdev; /* Upstream component of the Link */
@@ -275,10 +274,10 @@ static int policy_to_aspm_state(struct pcie_link_state *link)
return 0;
case POLICY_POWERSAVE:
/* Enable ASPM L0s/L1 */
- return (ASPM_STATE_L0S | ASPM_STATE_L1);
+ return PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1;
case POLICY_POWER_SUPERSAVE:
/* Enable Everything */
- return ASPM_STATE_ALL;
+ return PCIE_LINK_STATE_ASPM_ALL;
case POLICY_DEFAULT:
return link->aspm_default;
}
@@ -581,14 +580,14 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint)
latency_dw_l1 = calc_l1_latency(lnkcap_dw);
/* Check upstream direction L0s latency */
- if ((link->aspm_capable & ASPM_STATE_L0S_UP) &&
+ if ((link->aspm_capable & PCIE_LINK_STATE_L0S_UP) &&
(latency_up_l0s > acceptable_l0s))
- link->aspm_capable &= ~ASPM_STATE_L0S_UP;
+ link->aspm_capable &= ~PCIE_LINK_STATE_L0S_UP;
/* Check downstream direction L0s latency */
- if ((link->aspm_capable & ASPM_STATE_L0S_DW) &&
+ if ((link->aspm_capable & PCIE_LINK_STATE_L0S_DW) &&
(latency_dw_l0s > acceptable_l0s))
- link->aspm_capable &= ~ASPM_STATE_L0S_DW;
+ link->aspm_capable &= ~PCIE_LINK_STATE_L0S_DW;
/*
* Check L1 latency.
* Every switch on the path to root complex need 1
@@ -603,9 +602,9 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint)
* substate latencies (and hence do not do any check).
*/
latency = max_t(u32, latency_up_l1, latency_dw_l1);
- if ((link->aspm_capable & ASPM_STATE_L1) &&
+ if ((link->aspm_capable & PCIE_LINK_STATE_L1) &&
(latency + l1_switch_latency > acceptable_l1))
- link->aspm_capable &= ~ASPM_STATE_L1;
+ link->aspm_capable &= ~PCIE_LINK_STATE_L1;
l1_switch_latency += NSEC_PER_USEC;
link = link->parent;
@@ -741,13 +740,13 @@ static void aspm_l1ss_init(struct pcie_link_state *link)
child_l1ss_cap &= ~PCI_L1SS_CAP_ASPM_L1_2;
if (parent_l1ss_cap & child_l1ss_cap & PCI_L1SS_CAP_ASPM_L1_1)
- link->aspm_support |= ASPM_STATE_L1_1;
+ link->aspm_support |= PCIE_LINK_STATE_L1_1;
if (parent_l1ss_cap & child_l1ss_cap & PCI_L1SS_CAP_ASPM_L1_2)
- link->aspm_support |= ASPM_STATE_L1_2;
+ link->aspm_support |= PCIE_LINK_STATE_L1_2;
if (parent_l1ss_cap & child_l1ss_cap & PCI_L1SS_CAP_PCIPM_L1_1)
- link->aspm_support |= ASPM_STATE_L1_1_PCIPM;
+ link->aspm_support |= PCIE_LINK_STATE_L1_1_PCIPM;
if (parent_l1ss_cap & child_l1ss_cap & PCI_L1SS_CAP_PCIPM_L1_2)
- link->aspm_support |= ASPM_STATE_L1_2_PCIPM;
+ link->aspm_support |= PCIE_LINK_STATE_L1_2_PCIPM;
if (parent_l1ss_cap)
pci_read_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
@@ -757,15 +756,15 @@ static void aspm_l1ss_init(struct pcie_link_state *link)
&child_l1ss_ctl1);
if (parent_l1ss_ctl1 & child_l1ss_ctl1 & PCI_L1SS_CTL1_ASPM_L1_1)
- link->aspm_enabled |= ASPM_STATE_L1_1;
+ link->aspm_enabled |= PCIE_LINK_STATE_L1_1;
if (parent_l1ss_ctl1 & child_l1ss_ctl1 & PCI_L1SS_CTL1_ASPM_L1_2)
- link->aspm_enabled |= ASPM_STATE_L1_2;
+ link->aspm_enabled |= PCIE_LINK_STATE_L1_2;
if (parent_l1ss_ctl1 & child_l1ss_ctl1 & PCI_L1SS_CTL1_PCIPM_L1_1)
- link->aspm_enabled |= ASPM_STATE_L1_1_PCIPM;
+ link->aspm_enabled |= PCIE_LINK_STATE_L1_1_PCIPM;
if (parent_l1ss_ctl1 & child_l1ss_ctl1 & PCI_L1SS_CTL1_PCIPM_L1_2)
- link->aspm_enabled |= ASPM_STATE_L1_2_PCIPM;
+ link->aspm_enabled |= PCIE_LINK_STATE_L1_2_PCIPM;
- if (link->aspm_support & ASPM_STATE_L1_2_MASK)
+ if (link->aspm_support & PCIE_LINK_STATE_L1_2_MASK)
aspm_calc_l12_info(link, parent_l1ss_cap, child_l1ss_cap);
}
@@ -778,8 +777,8 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
if (blacklist) {
/* Set enabled/disable so that we will disable ASPM later */
- link->aspm_enabled = ASPM_STATE_ALL;
- link->aspm_disable = ASPM_STATE_ALL;
+ link->aspm_enabled = PCIE_LINK_STATE_ASPM_ALL;
+ link->aspm_disable = PCIE_LINK_STATE_ASPM_ALL;
return;
}
@@ -814,19 +813,19 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
* support L0s.
*/
if (parent_lnkcap & child_lnkcap & PCI_EXP_LNKCAP_ASPM_L0S)
- link->aspm_support |= ASPM_STATE_L0S;
+ link->aspm_support |= PCIE_LINK_STATE_L0S;
if (child_lnkctl & PCI_EXP_LNKCTL_ASPM_L0S)
- link->aspm_enabled |= ASPM_STATE_L0S_UP;
+ link->aspm_enabled |= PCIE_LINK_STATE_L0S_UP;
if (parent_lnkctl & PCI_EXP_LNKCTL_ASPM_L0S)
- link->aspm_enabled |= ASPM_STATE_L0S_DW;
+ link->aspm_enabled |= PCIE_LINK_STATE_L0S_DW;
/* Setup L1 state */
if (parent_lnkcap & child_lnkcap & PCI_EXP_LNKCAP_ASPM_L1)
- link->aspm_support |= ASPM_STATE_L1;
+ link->aspm_support |= PCIE_LINK_STATE_L1;
if (parent_lnkctl & child_lnkctl & PCI_EXP_LNKCTL_ASPM_L1)
- link->aspm_enabled |= ASPM_STATE_L1;
+ link->aspm_enabled |= PCIE_LINK_STATE_L1;
aspm_l1ss_init(link);
@@ -876,7 +875,7 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
* If needed, disable L1, and it gets enabled later
* in pcie_config_aspm_link().
*/
- if (enable_req & (ASPM_STATE_L1_1 | ASPM_STATE_L1_2)) {
+ if (enable_req & (PCIE_LINK_STATE_L1_1 | PCIE_LINK_STATE_L1_2)) {
pcie_capability_clear_word(child, PCI_EXP_LNKCTL,
PCI_EXP_LNKCTL_ASPM_L1);
pcie_capability_clear_word(parent, PCI_EXP_LNKCTL,
@@ -884,13 +883,13 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
}
val = 0;
- if (state & ASPM_STATE_L1_1)
+ if (state & PCIE_LINK_STATE_L1_1)
val |= PCI_L1SS_CTL1_ASPM_L1_1;
- if (state & ASPM_STATE_L1_2)
+ if (state & PCIE_LINK_STATE_L1_2)
val |= PCI_L1SS_CTL1_ASPM_L1_2;
- if (state & ASPM_STATE_L1_1_PCIPM)
+ if (state & PCIE_LINK_STATE_L1_1_PCIPM)
val |= PCI_L1SS_CTL1_PCIPM_L1_1;
- if (state & ASPM_STATE_L1_2_PCIPM)
+ if (state & PCIE_LINK_STATE_L1_2_PCIPM)
val |= PCI_L1SS_CTL1_PCIPM_L1_2;
/* Enable what we need to enable */
@@ -916,29 +915,29 @@ static void pcie_config_aspm_link(struct pcie_link_state *link, u32 state)
state &= (link->aspm_capable & ~link->aspm_disable);
/* Can't enable any substates if L1 is not enabled */
- if (!(state & ASPM_STATE_L1))
- state &= ~ASPM_STATE_L1SS;
+ if (!(state & PCIE_LINK_STATE_L1))
+ state &= ~PCIE_LINK_STATE_L1SS;
/* Spec says both ports must be in D0 before enabling PCI PM substates*/
if (parent->current_state != PCI_D0 || child->current_state != PCI_D0) {
- state &= ~ASPM_STATE_L1_SS_PCIPM;
- state |= (link->aspm_enabled & ASPM_STATE_L1_SS_PCIPM);
+ state &= ~PCIE_LINK_STATE_L1_SS_PCIPM;
+ state |= (link->aspm_enabled & PCIE_LINK_STATE_L1_SS_PCIPM);
}
/* Nothing to do if the link is already in the requested state */
if (link->aspm_enabled == state)
return;
/* Convert ASPM state to upstream/downstream ASPM register state */
- if (state & ASPM_STATE_L0S_UP)
+ if (state & PCIE_LINK_STATE_L0S_UP)
dwstream |= PCI_EXP_LNKCTL_ASPM_L0S;
- if (state & ASPM_STATE_L0S_DW)
+ if (state & PCIE_LINK_STATE_L0S_DW)
upstream |= PCI_EXP_LNKCTL_ASPM_L0S;
- if (state & ASPM_STATE_L1) {
+ if (state & PCIE_LINK_STATE_L1) {
upstream |= PCI_EXP_LNKCTL_ASPM_L1;
dwstream |= PCI_EXP_LNKCTL_ASPM_L1;
}
- if (link->aspm_capable & ASPM_STATE_L1SS)
+ if (link->aspm_capable & PCIE_LINK_STATE_L1SS)
pcie_config_aspm_l1ss(link, state);
/*
@@ -947,11 +946,11 @@ static void pcie_config_aspm_link(struct pcie_link_state *link, u32 state)
* upstream component first and then downstream, and vice
* versa for disabling ASPM L1. Spec doesn't mention L0S.
*/
- if (state & ASPM_STATE_L1)
+ if (state & PCIE_LINK_STATE_L1)
pcie_config_aspm_dev(parent, upstream);
list_for_each_entry(child, &linkbus->devices, bus_list)
pcie_config_aspm_dev(child, dwstream);
- if (!(state & ASPM_STATE_L1))
+ if (!(state & PCIE_LINK_STATE_L1))
pcie_config_aspm_dev(parent, upstream);
link->aspm_enabled = state;
@@ -1324,6 +1323,28 @@ static struct pcie_link_state *pcie_aspm_get_link(struct pci_dev *pdev)
return bridge->link_state;
}
+static u8 pci_calc_aspm_disable_mask(int state)
+{
+ state &= ~PCIE_LINK_STATE_CLKPM;
+
+ /* L1 PM substates require L1 */
+ if (state & PCIE_LINK_STATE_L1)
+ state |= PCIE_LINK_STATE_L1SS;
+
+ return state;
+}
+
+static u8 pci_calc_aspm_enable_mask(int state)
+{
+ state &= ~PCIE_LINK_STATE_CLKPM;
+
+ /* L1 PM substates require L1 */
+ if (state & PCIE_LINK_STATE_L1SS)
+ state |= PCIE_LINK_STATE_L1;
+
+ return state;
+}
+
static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool locked)
{
struct pcie_link_state *link = pcie_aspm_get_link(pdev);
@@ -1346,19 +1367,7 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool locked
if (!locked)
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
- if (state & PCIE_LINK_STATE_L0S)
- link->aspm_disable |= ASPM_STATE_L0S;
- if (state & PCIE_LINK_STATE_L1)
- /* L1 PM substates require L1 */
- link->aspm_disable |= ASPM_STATE_L1 | ASPM_STATE_L1SS;
- if (state & PCIE_LINK_STATE_L1_1)
- link->aspm_disable |= ASPM_STATE_L1_1;
- if (state & PCIE_LINK_STATE_L1_2)
- link->aspm_disable |= ASPM_STATE_L1_2;
- if (state & PCIE_LINK_STATE_L1_1_PCIPM)
- link->aspm_disable |= ASPM_STATE_L1_1_PCIPM;
- if (state & PCIE_LINK_STATE_L1_2_PCIPM)
- link->aspm_disable |= ASPM_STATE_L1_2_PCIPM;
+ link->aspm_disable |= pci_calc_aspm_disable_mask(state);
pcie_config_aspm_link(link, policy_to_aspm_state(link));
if (state & PCIE_LINK_STATE_CLKPM)
@@ -1414,20 +1423,7 @@ static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked)
if (!locked)
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
- link->aspm_default = 0;
- if (state & PCIE_LINK_STATE_L0S)
- link->aspm_default |= ASPM_STATE_L0S;
- if (state & PCIE_LINK_STATE_L1)
- link->aspm_default |= ASPM_STATE_L1;
- /* L1 PM substates require L1 */
- if (state & PCIE_LINK_STATE_L1_1)
- link->aspm_default |= ASPM_STATE_L1_1 | ASPM_STATE_L1;
- if (state & PCIE_LINK_STATE_L1_2)
- link->aspm_default |= ASPM_STATE_L1_2 | ASPM_STATE_L1;
- if (state & PCIE_LINK_STATE_L1_1_PCIPM)
- link->aspm_default |= ASPM_STATE_L1_1_PCIPM | ASPM_STATE_L1;
- if (state & PCIE_LINK_STATE_L1_2_PCIPM)
- link->aspm_default |= ASPM_STATE_L1_2_PCIPM | ASPM_STATE_L1;
+ link->aspm_default = pci_calc_aspm_enable_mask(state);
pcie_config_aspm_link(link, policy_to_aspm_state(link));
link->clkpm_default = (state & PCIE_LINK_STATE_CLKPM) ? 1 : 0;
@@ -1563,12 +1559,12 @@ static ssize_t aspm_attr_store_common(struct device *dev,
if (state_enable) {
link->aspm_disable &= ~state;
/* need to enable L1 for substates */
- if (state & ASPM_STATE_L1SS)
- link->aspm_disable &= ~ASPM_STATE_L1;
+ if (state & PCIE_LINK_STATE_L1SS)
+ link->aspm_disable &= ~PCIE_LINK_STATE_L1;
} else {
link->aspm_disable |= state;
- if (state & ASPM_STATE_L1)
- link->aspm_disable |= ASPM_STATE_L1SS;
+ if (state & PCIE_LINK_STATE_L1)
+ link->aspm_disable |= PCIE_LINK_STATE_L1SS;
}
pcie_config_aspm_link(link, policy_to_aspm_state(link));
@@ -1582,12 +1578,12 @@ static ssize_t aspm_attr_store_common(struct device *dev,
#define ASPM_ATTR(_f, _s) \
static ssize_t _f##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
-{ return aspm_attr_show_common(dev, attr, buf, ASPM_STATE_##_s); } \
+{ return aspm_attr_show_common(dev, attr, buf, PCIE_LINK_STATE_##_s); } \
\
static ssize_t _f##_store(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t len) \
-{ return aspm_attr_store_common(dev, attr, buf, len, ASPM_STATE_##_s); }
+{ return aspm_attr_store_common(dev, attr, buf, len, PCIE_LINK_STATE_##_s); }
ASPM_ATTR(l0s_aspm, L0S)
ASPM_ATTR(l1_aspm, L1)
@@ -1654,12 +1650,12 @@ static umode_t aspm_ctrl_attrs_are_visible(struct kobject *kobj,
struct pci_dev *pdev = to_pci_dev(dev);
struct pcie_link_state *link = pcie_aspm_get_link(pdev);
static const u8 aspm_state_map[] = {
- ASPM_STATE_L0S,
- ASPM_STATE_L1,
- ASPM_STATE_L1_1,
- ASPM_STATE_L1_2,
- ASPM_STATE_L1_1_PCIPM,
- ASPM_STATE_L1_2_PCIPM,
+ PCIE_LINK_STATE_L0S,
+ PCIE_LINK_STATE_L1,
+ PCIE_LINK_STATE_L1_1,
+ PCIE_LINK_STATE_L1_2,
+ PCIE_LINK_STATE_L1_1_PCIPM,
+ PCIE_LINK_STATE_L1_2_PCIPM,
};
if (aspm_disabled || !link)
diff --git a/drivers/pci/pcie/edr.c b/drivers/pci/pcie/edr.c
index 5f4914d313a1..e86298dbbcff 100644
--- a/drivers/pci/pcie/edr.c
+++ b/drivers/pci/pcie/edr.c
@@ -32,10 +32,10 @@ static int acpi_enable_dpc(struct pci_dev *pdev)
int status = 0;
/*
- * Behavior when calling unsupported _DSM functions is undefined,
- * so check whether EDR_PORT_DPC_ENABLE_DSM is supported.
+ * Per PCI Firmware r3.3, sec 4.6.12, EDR_PORT_DPC_ENABLE_DSM is
+ * optional. Return success if it's not implemented.
*/
- if (!acpi_check_dsm(adev->handle, &pci_acpi_dsm_guid, 5,
+ if (!acpi_check_dsm(adev->handle, &pci_acpi_dsm_guid, 6,
1ULL << EDR_PORT_DPC_ENABLE_DSM))
return 0;
@@ -46,12 +46,7 @@ static int acpi_enable_dpc(struct pci_dev *pdev)
argv4.package.count = 1;
argv4.package.elements = &req;
- /*
- * Per Downstream Port Containment Related Enhancements ECN to PCI
- * Firmware Specification r3.2, sec 4.6.12, EDR_PORT_DPC_ENABLE_DSM is
- * optional. Return success if it's not implemented.
- */
- obj = acpi_evaluate_dsm(adev->handle, &pci_acpi_dsm_guid, 5,
+ obj = acpi_evaluate_dsm(adev->handle, &pci_acpi_dsm_guid, 6,
EDR_PORT_DPC_ENABLE_DSM, &argv4);
if (!obj)
return 0;
@@ -85,8 +80,9 @@ static struct pci_dev *acpi_dpc_port_get(struct pci_dev *pdev)
u16 port;
/*
- * Behavior when calling unsupported _DSM functions is undefined,
- * so check whether EDR_PORT_DPC_ENABLE_DSM is supported.
+ * If EDR_PORT_LOCATE_DSM is not implemented under the target of
+ * EDR, the target is the port that experienced the containment
+ * event (PCI Firmware r3.3, sec 4.6.13).
*/
if (!acpi_check_dsm(adev->handle, &pci_acpi_dsm_guid, 5,
1ULL << EDR_PORT_LOCATE_DSM))
@@ -104,6 +100,16 @@ static struct pci_dev *acpi_dpc_port_get(struct pci_dev *pdev)
}
/*
+ * Bit 31 represents the success/failure of the operation. If bit
+ * 31 is set, the operation failed.
+ */
+ if (obj->integer.value & BIT(31)) {
+ ACPI_FREE(obj);
+ pci_err(pdev, "Locate Port _DSM failed\n");
+ return NULL;
+ }
+
+ /*
* Firmware returns DPC port BDF details in following format:
* 15:8 = bus
* 7:3 = device
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 01:55:25 +0100