PCI/ASPM: Consolidate link state defines

The linux/pci.h and aspm.c files define their own sets of link state
related defines which are almost the same.

Consolidate the use of defines into those defined by linux/pci.h and expand
PCIE_LINK_STATE_L0S to match earlier ASPM_STATE_L0S that includes both
upstream and downstream bits. Rename also the defines that are internal to
aspm.c to start with PCIE_LINK_STATE for consistency.

While the PCIE_LINK_STATE_L0S BIT(0) -> (BIT(0) | BIT(1)) transformation is
not 1:1, in practice aspm.c already used ASPM_STATE_L0S that has both bits
enabled except during mapping.

While at it, place the PCIE_LINK_STATE_CLKPM define last to have more
logical grouping.

Use static_assert() to ensure PCIE_LINK_STATE_L0S is strictly equal to the
combination of PCIE_LINK_STATE_L0S_UP/DW.

Link: https://lore.kernel.org/r/20240322123952.6384-2-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 77 insertions, 78 deletions

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 2428d278e015..994b283b6a0f 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;
@@ -1347,18 +1346,18 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool locked
 		down_read(&pci_bus_sem);
 	mutex_lock(&aspm_lock);
 	if (state & PCIE_LINK_STATE_L0S)
-		link->aspm_disable |= ASPM_STATE_L0S;
+		link->aspm_disable |= PCIE_LINK_STATE_L0S;
 	if (state & PCIE_LINK_STATE_L1)
 		/* L1 PM substates require L1 */
-		link->aspm_disable |= ASPM_STATE_L1 | ASPM_STATE_L1SS;
+		link->aspm_disable |= PCIE_LINK_STATE_L1 | PCIE_LINK_STATE_L1SS;
 	if (state & PCIE_LINK_STATE_L1_1)
-		link->aspm_disable |= ASPM_STATE_L1_1;
+		link->aspm_disable |= PCIE_LINK_STATE_L1_1;
 	if (state & PCIE_LINK_STATE_L1_2)
-		link->aspm_disable |= ASPM_STATE_L1_2;
+		link->aspm_disable |= PCIE_LINK_STATE_L1_2;
 	if (state & PCIE_LINK_STATE_L1_1_PCIPM)
-		link->aspm_disable |= ASPM_STATE_L1_1_PCIPM;
+		link->aspm_disable |= PCIE_LINK_STATE_L1_1_PCIPM;
 	if (state & PCIE_LINK_STATE_L1_2_PCIPM)
-		link->aspm_disable |= ASPM_STATE_L1_2_PCIPM;
+		link->aspm_disable |= PCIE_LINK_STATE_L1_2_PCIPM;
 	pcie_config_aspm_link(link, policy_to_aspm_state(link));
 
 	if (state & PCIE_LINK_STATE_CLKPM)
@@ -1416,18 +1415,18 @@ static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked)
 	mutex_lock(&aspm_lock);
 	link->aspm_default = 0;
 	if (state & PCIE_LINK_STATE_L0S)
-		link->aspm_default |= ASPM_STATE_L0S;
+		link->aspm_default |= PCIE_LINK_STATE_L0S;
 	if (state & PCIE_LINK_STATE_L1)
-		link->aspm_default |= ASPM_STATE_L1;
+		link->aspm_default |= PCIE_LINK_STATE_L1;
 	/* L1 PM substates require L1 */
 	if (state & PCIE_LINK_STATE_L1_1)
-		link->aspm_default |= ASPM_STATE_L1_1 | ASPM_STATE_L1;
+		link->aspm_default |= PCIE_LINK_STATE_L1_1 | PCIE_LINK_STATE_L1;
 	if (state & PCIE_LINK_STATE_L1_2)
-		link->aspm_default |= ASPM_STATE_L1_2 | ASPM_STATE_L1;
+		link->aspm_default |= PCIE_LINK_STATE_L1_2 | PCIE_LINK_STATE_L1;
 	if (state & PCIE_LINK_STATE_L1_1_PCIPM)
-		link->aspm_default |= ASPM_STATE_L1_1_PCIPM | ASPM_STATE_L1;
+		link->aspm_default |= PCIE_LINK_STATE_L1_1_PCIPM | PCIE_LINK_STATE_L1;
 	if (state & PCIE_LINK_STATE_L1_2_PCIPM)
-		link->aspm_default |= ASPM_STATE_L1_2_PCIPM | ASPM_STATE_L1;
+		link->aspm_default |= PCIE_LINK_STATE_L1_2_PCIPM | PCIE_LINK_STATE_L1;
 	pcie_config_aspm_link(link, policy_to_aspm_state(link));
 
 	link->clkpm_default = (state & PCIE_LINK_STATE_CLKPM) ? 1 : 0;
@@ -1563,12 +1562,12 @@ 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 +1581,12 @@ 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 +1653,12 @@ 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)