[RFC PATCH v5 4/4] PCI/ASPM: Remove struct aspm_latency

Saheed O. Bolarinwa
2021-11-19T19:39:37Z

The struct aspm_latency is now used only inside pcie_aspm_check_latency().

- replace struct aspm_latency variables with u32 variables
- remove struct aspm_latency

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
---
drivers/pci/pcie/aspm.c | 32 +++++++++++++-------------------
1 file changed, 13 insertions(+), 19 deletions(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index a8821fe1ffe7..e29611080a90 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -41,11 +41,6 @@
#define ASPM_STATE_ALL (ASPM_STATE_L0S | ASPM_STATE_L1 | \
ASPM_STATE_L1SS)

-struct aspm_latency {
- u32 l0s; /* L0s latency (nsec) */
- u32 l1; /* L1 latency (nsec) */
-};
-
struct pcie_link_state {
struct pci_dev *pdev; /* Upstream component of the Link */
struct pci_dev *downstream; /* Downstream component, function 0 */
@@ -384,9 +379,9 @@ static void encode_l12_threshold(u32 threshold_us, u32 *scale, u32 *value)
static void pcie_aspm_check_latency(struct pci_dev *endpoint)
{
u32 reg32, latency, encoding, lnkcap_up, lnkcap_dw;
- u32 l1_switch_latency = 0;
- struct aspm_latency latency_up, latency_dw;
- struct aspm_latency *acceptable;
+ u32 l1_switch_latency = 0, latency_up_l0s;
+ u32 latency_up_l1, latency_dw_l0s, latency_dw_l1;
+ u32 acceptable_l0s, acceptable_l1;
struct pcie_link_state *link;

/* Device not in D0 doesn't need latency check */
@@ -398,10 +393,10 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint)
pcie_capability_read_dword(endpoint, PCI_EXP_DEVCAP, &reg32);
/* Calculate endpoint L0s acceptable latency */
encoding = (reg32 & PCI_EXP_DEVCAP_L0S) >> 6;
- acceptable->l0s = calc_l0s_acceptable(encoding);
+ acceptable_l0s = calc_l0s_acceptable(encoding);
/* Calculate endpoint L1 acceptable latency */
encoding = (reg32 & PCI_EXP_DEVCAP_L1) >> 9;
- acceptable->l1 = calc_l1_acceptable(encoding);
+ acceptable_l1 = calc_l1_acceptable(encoding);

while (link) {
struct pci_dev *dev = pci_function_0(
@@ -414,19 +409,19 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint)
pcie_capability_read_dword(dev,
PCI_EXP_LNKCAP,
&lnkcap_dw);
- latency_up.l0s = calc_l0s_latency(lnkcap_up);
- latency_up.l1 = calc_l1_latency(lnkcap_up);
- latency_dw.l0s = calc_l0s_latency(lnkcap_dw);
- latency_dw.l1 = calc_l1_latency(lnkcap_dw);
+ latency_up_l0s = calc_l0s_latency(lnkcap_up);
+ latency_up_l1 = calc_l1_latency(lnkcap_up);
+ latency_dw_l0s = calc_l0s_latency(lnkcap_dw);
+ latency_dw_l1 = calc_l1_latency(lnkcap_dw);

/* Check upstream direction L0s latency */
if ((link->aspm_capable & ASPM_STATE_L0S_UP) &&
- (latency_up.l0s > acceptable->l0s))
+ (latency_up_l0s > acceptable_l0s))
link->aspm_capable &= ~ASPM_STATE_L0S_UP;

/* Check downstream direction L0s latency */
if ((link->aspm_capable & ASPM_STATE_L0S_DW) &&
- (latency_dw.l0s > acceptable->l0s))
+ (latency_dw_l0s > acceptable_l0s))
link->aspm_capable &= ~ASPM_STATE_L0S_DW;
/*
* Check L1 latency.
@@ -441,9 +436,9 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint)
* L1 exit latencies advertised by a device include L1
* substate latencies (and hence do not do any check).
*/
- latency = max_t(u32, latency_up.l1, latency_dw.l1);
+ latency = max_t(u32, latency_up_l1, latency_dw_l1);
if ((link->aspm_capable & ASPM_STATE_L1) &&
- (latency + l1_switch_latency > acceptable->l1))
+ (latency + l1_switch_latency > acceptable_l1))
link->aspm_capable &= ~ASPM_STATE_L1;
l1_switch_latency += 1000;

@@ -670,7 +665,6 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)

/* Get and check endpoint acceptable latencies */
list_for_each_entry(child, &linkbus->devices, bus_list) {
-
if (pci_pcie_type(child) != PCI_EXP_TYPE_ENDPOINT &&
pci_pcie_type(child) != PCI_EXP_TYPE_LEG_END)
continue;
--
2.20.1