[RFC PATCH v1 2/4] PCI/ASPM: Remove struct pcie_link_state.clkpm_capable

Saheed O. Bolarinwa
2021-09-29T00:44:20Z

From: "Bolarinwa O. Saheed" <refactormyself@gmail.com>

The clkpm_capable member of the struct pcie_link_state indicates
if the device is Clock PM capable. This can be calculated when
it is needed.

This patch:
- removes clkpm_capable from struct pcie_link_state
- moves the calculation of clkpm_capable into
pcie_is_clkpm_capable()
- replaces references to clkpm_capable with a call to
pcie_is_clkpm_capable()

Signed-off-by: Bolarinwa O. Saheed <refactormyself@gmail.com>
---
drivers/pci/pcie/aspm.c | 39 ++++++++++++++++++++++-----------------
1 file changed, 22 insertions(+), 17 deletions(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index c23da9a4e2fb..9e65da9a22dd 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -61,7 +61,6 @@ struct pcie_link_state {
u32 aspm_disable:7; /* Disabled ASPM state */

/* Clock PM state */
- u32 clkpm_capable:1; /* Clock PM capable? */
u32 clkpm_enabled:1; /* Current Clock PM state */
u32 clkpm_disable:1; /* Clock PM disabled */

@@ -146,6 +145,25 @@ static int pcie_get_clkpm_state(struct pci_dev *pdev)
return enabled;
}

+static int pcie_is_clkpm_capable(struct pci_dev *pdev)
+{
+ int capable = 1;
+ u32 reg32;
+ struct pci_dev *child;
+ struct pci_bus *linkbus = pdev->subordinate;
+
+ /* All functions should have the same cap state, take the worst */
+ list_for_each_entry(child, &linkbus->devices, bus_list) {
+ pcie_capability_read_dword(child, PCI_EXP_LNKCAP, &reg32);
+ if (!(reg32 & PCI_EXP_LNKCAP_CLKPM)) {
+ capable = 0;
+ break;
+ }
+ }
+
+ return capable;
+}
+
static int policy_to_clkpm_state(struct pcie_link_state *link)
{
switch (aspm_policy) {
@@ -177,11 +195,12 @@ static void pcie_set_clkpm_nocheck(struct pcie_link_state *link, int enable)

static void pcie_set_clkpm(struct pcie_link_state *link, int enable)
{
+ int capable = pcie_is_clkpm_capable(link->pdev);
/*
* Don't enable Clock PM if the link is not Clock PM capable
* or Clock PM is disabled
*/
- if (!link->clkpm_capable || link->clkpm_disable)
+ if (!capable || link->clkpm_disable)
enable = 0;
/* Need nothing if the specified equals to current state */
if (link->clkpm_enabled == enable)
@@ -191,21 +210,7 @@ static void pcie_set_clkpm(struct pcie_link_state *link, int enable)

static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist)
{
- int capable = 1;
- u32 reg32;
- struct pci_dev *child;
- struct pci_bus *linkbus = link->pdev->subordinate;
-
- /* All functions should have the same cap and state, take the worst */
- list_for_each_entry(child, &linkbus->devices, bus_list) {
- pcie_capability_read_dword(child, PCI_EXP_LNKCAP, &reg32);
- if (!(reg32 & PCI_EXP_LNKCAP_CLKPM)) {
- capable = 0;
- break;
- }
- }
link->clkpm_enabled = pcie_get_clkpm_state(link->pdev);
- link->clkpm_capable = capable;
link->clkpm_disable = blacklist ? 1 : 0;
}

@@ -1346,7 +1351,7 @@ static umode_t aspm_ctrl_attrs_are_visible(struct kobject *kobj,
return 0;

if (n == 0)
- return link->clkpm_capable ? a->mode : 0;
+ return pcie_is_clkpm_capable(link->pdev) ? a->mode : 0;

return link->aspm_capable & aspm_state_map[n - 1] ? a->mode : 0;
}
--
2.20.1