[PATCH v11 3/5] PCI: Move pci_clear_and_set_dword() helper to PCI header

Shuai Xue xueshuai at linux.alibaba.com
Mon Nov 20 17:33:58 PST 2023


The clear and set pattern is commonly used for accessing PCI config,
move the helper pci_clear_and_set_dword() from aspm.c into PCI header.
In addition, rename to pci_clear_and_set_config_dword() to retain the
"config" information and match the other accessors.

No functional change intended.

Signed-off-by: Shuai Xue <xueshuai at linux.alibaba.com>
Acked-by: Bjorn Helgaas <bhelgaas at google.com>
Tested-by: Ilkka Koskinen <ilkka at os.amperecomputing.com>
---
 drivers/pci/access.c    | 12 ++++++++
 drivers/pci/pcie/aspm.c | 65 +++++++++++++++++++----------------------
 include/linux/pci.h     |  2 ++
 3 files changed, 44 insertions(+), 35 deletions(-)

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 6554a2e89d36..6449056b57dd 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -598,3 +598,15 @@ int pci_write_config_dword(const struct pci_dev *dev, int where,
 	return pci_bus_write_config_dword(dev->bus, dev->devfn, where, val);
 }
 EXPORT_SYMBOL(pci_write_config_dword);
+
+void pci_clear_and_set_config_dword(const struct pci_dev *dev, int pos,
+				    u32 clear, u32 set)
+{
+	u32 val;
+
+	pci_read_config_dword(dev, pos, &val);
+	val &= ~clear;
+	val |= set;
+	pci_write_config_dword(dev, pos, val);
+}
+EXPORT_SYMBOL(pci_clear_and_set_config_dword);
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 1bf630059264..9dbc4d3c2591 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -423,17 +423,6 @@ static void pcie_aspm_check_latency(struct pci_dev *endpoint)
 	}
 }
 
-static void pci_clear_and_set_dword(struct pci_dev *pdev, int pos,
-				    u32 clear, u32 set)
-{
-	u32 val;
-
-	pci_read_config_dword(pdev, pos, &val);
-	val &= ~clear;
-	val |= set;
-	pci_write_config_dword(pdev, pos, val);
-}
-
 /* Calculate L1.2 PM substate timing parameters */
 static void aspm_calc_l12_info(struct pcie_link_state *link,
 				u32 parent_l1ss_cap, u32 child_l1ss_cap)
@@ -494,10 +483,12 @@ static void aspm_calc_l12_info(struct pcie_link_state *link,
 	cl1_2_enables = cctl1 & PCI_L1SS_CTL1_L1_2_MASK;
 
 	if (pl1_2_enables || cl1_2_enables) {
-		pci_clear_and_set_dword(child, child->l1ss + PCI_L1SS_CTL1,
-					PCI_L1SS_CTL1_L1_2_MASK, 0);
-		pci_clear_and_set_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
-					PCI_L1SS_CTL1_L1_2_MASK, 0);
+		pci_clear_and_set_config_dword(child,
+					       child->l1ss + PCI_L1SS_CTL1,
+					       PCI_L1SS_CTL1_L1_2_MASK, 0);
+		pci_clear_and_set_config_dword(parent,
+					       parent->l1ss + PCI_L1SS_CTL1,
+					       PCI_L1SS_CTL1_L1_2_MASK, 0);
 	}
 
 	/* Program T_POWER_ON times in both ports */
@@ -505,22 +496,26 @@ static void aspm_calc_l12_info(struct pcie_link_state *link,
 	pci_write_config_dword(child, child->l1ss + PCI_L1SS_CTL2, ctl2);
 
 	/* Program Common_Mode_Restore_Time in upstream device */
-	pci_clear_and_set_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_CM_RESTORE_TIME, ctl1);
+	pci_clear_and_set_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_CM_RESTORE_TIME, ctl1);
 
 	/* Program LTR_L1.2_THRESHOLD time in both ports */
-	pci_clear_and_set_dword(parent,	parent->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_LTR_L12_TH_VALUE |
-				PCI_L1SS_CTL1_LTR_L12_TH_SCALE, ctl1);
-	pci_clear_and_set_dword(child, child->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_LTR_L12_TH_VALUE |
-				PCI_L1SS_CTL1_LTR_L12_TH_SCALE, ctl1);
+	pci_clear_and_set_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_LTR_L12_TH_VALUE |
+				       PCI_L1SS_CTL1_LTR_L12_TH_SCALE,
+				       ctl1);
+	pci_clear_and_set_config_dword(child, child->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_LTR_L12_TH_VALUE |
+				       PCI_L1SS_CTL1_LTR_L12_TH_SCALE,
+				       ctl1);
 
 	if (pl1_2_enables || cl1_2_enables) {
-		pci_clear_and_set_dword(parent, parent->l1ss + PCI_L1SS_CTL1, 0,
-					pl1_2_enables);
-		pci_clear_and_set_dword(child, child->l1ss + PCI_L1SS_CTL1, 0,
-					cl1_2_enables);
+		pci_clear_and_set_config_dword(parent,
+					       parent->l1ss + PCI_L1SS_CTL1, 0,
+					       pl1_2_enables);
+		pci_clear_and_set_config_dword(child,
+					       child->l1ss + PCI_L1SS_CTL1, 0,
+					       cl1_2_enables);
 	}
 }
 
@@ -680,10 +675,10 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
 	 */
 
 	/* Disable all L1 substates */
-	pci_clear_and_set_dword(child, child->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_L1SS_MASK, 0);
-	pci_clear_and_set_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_L1SS_MASK, 0);
+	pci_clear_and_set_config_dword(child, child->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_L1SS_MASK, 0);
+	pci_clear_and_set_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_L1SS_MASK, 0);
 	/*
 	 * If needed, disable L1, and it gets enabled later
 	 * in pcie_config_aspm_link().
@@ -706,10 +701,10 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
 		val |= PCI_L1SS_CTL1_PCIPM_L1_2;
 
 	/* Enable what we need to enable */
-	pci_clear_and_set_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_L1SS_MASK, val);
-	pci_clear_and_set_dword(child, child->l1ss + PCI_L1SS_CTL1,
-				PCI_L1SS_CTL1_L1SS_MASK, val);
+	pci_clear_and_set_config_dword(parent, parent->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_L1SS_MASK, val);
+	pci_clear_and_set_config_dword(child, child->l1ss + PCI_L1SS_CTL1,
+				       PCI_L1SS_CTL1_L1SS_MASK, val);
 }
 
 static void pcie_config_aspm_dev(struct pci_dev *pdev, u32 val)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 8c7c2c3c6c65..72b0fb82a820 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1213,6 +1213,8 @@ int pci_read_config_dword(const struct pci_dev *dev, int where, u32 *val);
 int pci_write_config_byte(const struct pci_dev *dev, int where, u8 val);
 int pci_write_config_word(const struct pci_dev *dev, int where, u16 val);
 int pci_write_config_dword(const struct pci_dev *dev, int where, u32 val);
+void pci_clear_and_set_config_dword(const struct pci_dev *dev, int pos,
+				    u32 clear, u32 set);
 
 int pcie_capability_read_word(struct pci_dev *dev, int pos, u16 *val);
 int pcie_capability_read_dword(struct pci_dev *dev, int pos, u32 *val);
-- 
2.39.3




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