[PATCH v2 3/7] PCI/ASPM: Compute the value of aspm_register_info.support directly

From: "Saheed O. Bolarinwa" <refactormyself@gmail.com>
To: helgaas@kernel.org
Cc: "Saheed O. Bolarinwa" <refactormyself@gmail.com>,
	linux-pci@vger.kernel.org
Subject: [PATCH v2 3/7] PCI/ASPM: Compute the value of aspm_register_info.support directly
Date: Thu, 24 Sep 2020 16:24:39 +0200	[thread overview]
Message-ID: <20200924142443.260861-4-refactormyself@gmail.com> (raw)
In-Reply-To: <20200924142443.260861-1-refactormyself@gmail.com>

 - Calculate aspm_register_info.support inside aspm_support()
 - Replace references to aspm_register_info.support with aspm_support().
 - In pcie_get_aspm_reg() remove assignment to aspm_register_info.support
 - Remove aspm_register_info.support

Signed-off-by: Saheed O. Bolarinwa <refactormyself@gmail.com>
---
 drivers/pci/pcie/aspm.c | 22 +++++++++++++---------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 5f7cf47b6a40..321b328347c1 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -383,7 +383,6 @@ static void encode_l12_threshold(u32 threshold_us, u32 *scale, u32 *value)
 }
 
 struct aspm_register_info {
-	u32 support:2;
 	u32 enabled:2;
 
 	/* L1 substates */
@@ -396,12 +395,10 @@ struct aspm_register_info {
 static void pcie_get_aspm_reg(struct pci_dev *pdev,
 			      struct aspm_register_info *info)
 {
-	u16 reg16;
-	u32 reg32 = pdev->lnkcap;
+	u16 ctl;
 
-	info->support = (reg32 & PCI_EXP_LNKCAP_ASPMS) >> 10;
-	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &reg16);
-	info->enabled = reg16 & PCI_EXP_LNKCTL_ASPMC;
+	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &ctl);
+	info->enabled = ctl & PCI_EXP_LNKCTL_ASPMC;
 
 	/* Read L1 PM substate capabilities */
 	info->l1ss_cap = info->l1ss_ctl1 = info->l1ss_ctl2 = 0;
@@ -540,6 +537,11 @@ static void aspm_calc_l1ss_info(struct pcie_link_state *link,
 	link->l1ss.ctl1 |= t_common_mode << 8 | scale << 29 | value << 16;
 }
 
+static void aspm_support(struct pci_dev *pdev)
+{
+	return (pdev->lnkcap & PCI_EXP_LNKCAP_ASPMS) >> 10;
+}
+
 static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
 {
 	struct pci_dev *child = link->downstream, *parent = link->pdev;
@@ -561,7 +563,7 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
 	 * If ASPM not supported, don't mess with the clocks and link,
 	 * bail out now.
 	 */
-	if (!(upreg.support & dwreg.support))
+	if (!(aspm_support(parent) & aspm_support(child)))
 		return;
 
 	/* Configure common clock before checking latencies */
@@ -581,8 +583,9 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
 	 * given link unless components on both sides of the link each
 	 * support L0s.
 	 */
-	if (dwreg.support & upreg.support & PCIE_LINK_STATE_L0S)
+	if (aspm_support(parent) & aspm_support(child) & PCIE_LINK_STATE_L0S)
 		link->aspm_support |= ASPM_STATE_L0S;
+
 	if (dwreg.enabled & PCIE_LINK_STATE_L0S)
 		link->aspm_enabled |= ASPM_STATE_L0S_UP;
 	if (upreg.enabled & PCIE_LINK_STATE_L0S)
@@ -591,8 +594,9 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist)
 	link->latency_dw.l0s = calc_l0s_latency(child);
 
 	/* Setup L1 state */
-	if (upreg.support & dwreg.support & PCIE_LINK_STATE_L1)
+	if (aspm_support(parent) & aspm_support(child) & PCIE_LINK_STATE_L1)
 		link->aspm_support |= ASPM_STATE_L1;
+
 	if (upreg.enabled & dwreg.enabled & PCIE_LINK_STATE_L1)
 		link->aspm_enabled |= ASPM_STATE_L1;
 	link->latency_up.l1 = calc_l1_latency(parent);
-- 
2.18.4

