Merge branch 'pci/controller/dwc-qcom'

- Set max OPP during resume so DBI register accesses don't fail with NoC
  errors (Qiang Yu)

- Add pci_host_common_d3cold_possible() to determine whether downstream
  devices are already in D3hot and wakeup-enabled devices are capable of
  generating PME from D3cold (Krishna Chaitanya Chundru)

- Add a .get_ltssm() callback to get the LTSSM status without DBI, since
  DBI may be inaccessible after PME_Turn_Off (Krishna Chaitanya Chundru)

- Power down PHY via PARF_PHY_CTRL before disabling rails/clocks to avoid
  power leakage (Krishna Chaitanya Chundru)

- Decide whether suspend should put the link in L2 and power down using
  pci_host_common_d3cold_possible() instead of checking whether ASPM L1 is
  enabled (Krishna Chaitanya Chundru)

- Add qcom D3cold support to tear down interconnect bandwidth and OPP votes
  (Krishna Chaitanya Chundru)

- Handle unsupported mixed PERST#/PHY DT configurations, e.g., PHY in RP
  node while PERST# is in the RC node, but warn about the DT issue (Qiang
  Yu)

- Add pcie_encode_t_power_on() to encode L1SS T_POWER_ON fields (Krishna
  Chaitanya Chundru)

- Add dw_pcie_program_t_power_on() to program T_POWER_ON (Krishna Chaitanya
  Chundru)

- Program qcom T_POWER_ON based on DT 't-power-on-us' property in case
  hardware advertises incorrect values (Krishna Chaitanya Chundru)

- Disable ASPM L0s for SA8775P (Shawn Guo)

- Initialize DWC MSI lock for firmware-managed ECAM hosts, which don't use
  the dw_pcie_host_init() path that initializes the lock (Yadu M G)

* pci/controller/dwc-qcom:
  PCI: qcom: Initialize DWC MSI lock for firmware-managed ECAM hosts
  PCI: qcom: Disable ASPM L0s for SA8775P
  PCI: qcom: Program T_POWER_ON
  PCI: dwc: Add dw_pcie_program_t_power_on() to program T_POWER_ON
  PCI/ASPM: Add pcie_encode_t_power_on() helper to encode L1SS T_POWER_ON fields
  PCI: qcom: Handle mixed PERST#/PHY DT configuration
  PCI: qcom: Add D3cold support
  PCI: dwc: Use common D3cold eligibility helper in suspend path
  PCI: qcom: Power down PHY via PARF_PHY_CTRL before disabling rails/clocks
  PCI: qcom: Add .get_ltssm() callback to query LTSSM status
  PCI: host-common: Add pci_host_common_d3cold_possible() helper
  PCI: qcom: Set max OPP before DBI access during resume

# Conflicts:
#	drivers/pci/controller/pci-host-common.c

drivers/pci/controller/dwc/pcie-designware-host.c

@@ -16,9 +16,11 @@
 #include <linux/msi.h>
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
+#include <linux/pci.h>
 #include <linux/pci_regs.h>
 #include <linux/platform_device.h>
 
+#include "../pci-host-common.h"
 #include "../../pci.h"
 #include "pcie-designware.h"
 
@@ -1218,18 +1220,14 @@ static int dw_pcie_pme_turn_off(struct dw_pcie *pci)
 
 int dw_pcie_suspend_noirq(struct dw_pcie *pci)
 {
-	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+	bool pme_capable = false;
 	int ret = 0;
 	u32 val;
 
 	if (!dw_pcie_link_up(pci))
 		goto stop_link;
 
-	/*
-	 * If L1SS is supported, then do not put the link into L2 as some
-	 * devices such as NVMe expect low resume latency.
-	 */
-	if (dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKCTL) & PCI_EXP_LNKCTL_ASPM_L1)
+	if (!pci_host_common_d3cold_possible(pci->pp.bridge, &pme_capable))
 		return 0;
 
 	if (pci->pp.ops->pme_turn_off) {
@@ -1273,6 +1271,15 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci)
 	udelay(1);
 
 stop_link:
+	/*
+	 * TODO: "pme_capable" means some downstream device is wakeup-
+	 * enabled and is capable of generating PME from D3cold, which
+	 * requires auxiliary power.  Instead of always skipping power off
+	 * if PME is supported from D3cold, query the pwrctrl core and skip
+	 * power off only if device supports PME from D3cold and Vaux is
+	 * not supported.
+	 */
+	pci->pp.skip_pwrctrl_off = pme_capable;
 	dw_pcie_stop_link(pci);
 	if (pci->pp.ops->deinit)
 		pci->pp.ops->deinit(&pci->pp);
@@ -1290,8 +1297,6 @@ int dw_pcie_resume_noirq(struct dw_pcie *pci)
 	if (!pci->suspended)
 		return 0;
 
-	pci->suspended = false;
-
 	if (pci->pp.ops->init) {
 		ret = pci->pp.ops->init(&pci->pp);
 		if (ret) {
@@ -1313,6 +1318,8 @@ int dw_pcie_resume_noirq(struct dw_pcie *pci)
 	if (pci->pp.ops->post_init)
 		pci->pp.ops->post_init(&pci->pp);
 
+	pci->suspended = false;
+
 	return 0;
 
 err_stop_link:

drivers/pci/controller/dwc/pcie-designware.c

@@ -1253,6 +1253,34 @@ void dw_pcie_hide_unsupported_l1ss(struct dw_pcie *pci)
 	dw_pcie_writel_dbi(pci, l1ss + PCI_L1SS_CAP, l1ss_cap);
 }
 
+/* TODO: Need to handle multi Root Ports */
+void dw_pcie_program_t_power_on(struct dw_pcie *pci, u32 t_power_on)
+{
+	u8 scale, value;
+	u16 offset;
+	u32 val;
+
+	if (!t_power_on)
+		return;
+
+	offset = dw_pcie_find_ext_capability(pci, PCI_EXT_CAP_ID_L1SS);
+	if (!offset)
+		return;
+
+	pcie_encode_t_power_on(t_power_on, &scale, &value);
+
+	dw_pcie_dbi_ro_wr_en(pci);
+
+	val = dw_pcie_readl_dbi(pci, offset + PCI_L1SS_CAP);
+	val &= ~(PCI_L1SS_CAP_P_PWR_ON_SCALE | PCI_L1SS_CAP_P_PWR_ON_VALUE);
+	FIELD_MODIFY(PCI_L1SS_CAP_P_PWR_ON_SCALE, &val, scale);
+	FIELD_MODIFY(PCI_L1SS_CAP_P_PWR_ON_VALUE, &val, value);
+
+	dw_pcie_writel_dbi(pci, offset + PCI_L1SS_CAP, val);
+
+	dw_pcie_dbi_ro_wr_dis(pci);
+}
+
 void dw_pcie_setup(struct dw_pcie *pci)
 {
 	u32 val;

drivers/pci/controller/dwc/pcie-designware.h

@@ -451,6 +451,7 @@ struct dw_pcie_rp {
 	bool			ecam_enabled;
 	bool			native_ecam;
 	bool                    skip_l23_ready;
+	bool			skip_pwrctrl_off;
 };
 
 struct dw_pcie_ep_ops {
@@ -608,6 +609,7 @@ int dw_pcie_prog_ep_inbound_atu(struct dw_pcie *pci, u8 func_no, int index,
 				u8 bar, size_t size);
 void dw_pcie_disable_atu(struct dw_pcie *pci, u32 dir, int index);
 void dw_pcie_hide_unsupported_l1ss(struct dw_pcie *pci);
+void dw_pcie_program_t_power_on(struct dw_pcie *pci, u32 t_power_on);
 void dw_pcie_setup(struct dw_pcie *pci);
 void dw_pcie_iatu_detect(struct dw_pcie *pci);
 int dw_pcie_edma_detect(struct dw_pcie *pci);

drivers/pci/controller/pci-host-common.c

@@ -186,6 +186,10 @@ err_cleanup:
 }
 EXPORT_SYMBOL_GPL(pci_host_common_parse_ports);
 
+#define PCI_HOST_D3COLD_ALLOWED        BIT(0)
+#define PCI_HOST_PME_D3COLD_CAPABLE    BIT(1)
+
+
 static void gen_pci_unmap_cfg(void *ptr)
 {
 	pci_ecam_free((struct pci_config_window *)ptr);
@@ -279,5 +283,64 @@ void pci_host_common_remove(struct platform_device *pdev)
 }
 EXPORT_SYMBOL_GPL(pci_host_common_remove);
 
+static int __pci_host_common_d3cold_possible(struct pci_dev *pdev,
+					     void *userdata)
+{
+	u32 *flags = userdata;
+
+	if (!pdev->dev.driver && !pci_is_enabled(pdev))
+		return 0;
+
+	if (pdev->current_state != PCI_D3hot)
+		goto exit;
+
+	if (device_may_wakeup(&pdev->dev)) {
+		if (!pci_pme_capable(pdev, PCI_D3cold))
+			goto exit;
+		else
+			*flags |= PCI_HOST_PME_D3COLD_CAPABLE;
+	}
+
+	return 0;
+
+exit:
+	*flags &= ~PCI_HOST_D3COLD_ALLOWED;
+
+	return -EOPNOTSUPP;
+}
+
+/**
+ * pci_host_common_d3cold_possible - Determine whether the host bridge can
+ *				     transition the devices into D3cold.
+ *
+ * @bridge: PCI host bridge to check
+ * @pme_capable: Pointer to update if there is any device capable of generating
+ *		 PME from D3cold.
+ *
+ * Walk downstream PCIe endpoint devices and determine whether the host bridge
+ * is permitted to transition the devices into D3cold.
+ *
+ * Devices under host bridge can enter D3cold only if all active PCIe
+ * endpoints are in PCI_D3hot and any wakeup-enabled endpoint is capable of
+ * generating PME from D3cold.  Inactive endpoints are ignored.
+ *
+ * The @pme_capable output allows PCIe controller drivers to apply
+ * platform-specific handling to preserve wakeup functionality.
+ *
+ * Return: %true if the host bridge may enter D3cold, otherwise %false.
+ */
+bool pci_host_common_d3cold_possible(struct pci_host_bridge *bridge,
+				     bool *pme_capable)
+{
+	u32 flags = PCI_HOST_D3COLD_ALLOWED;
+
+	pci_walk_bus(bridge->bus, __pci_host_common_d3cold_possible, &flags);
+
+	*pme_capable = !!(flags & PCI_HOST_PME_D3COLD_CAPABLE);
+
+	return !!(flags & PCI_HOST_D3COLD_ALLOWED);
+}
+EXPORT_SYMBOL_GPL(pci_host_common_d3cold_possible);
+
 MODULE_DESCRIPTION("Common library for PCI host controller drivers");
 MODULE_LICENSE("GPL v2");

drivers/pci/controller/pci-host-common.h

@@ -48,4 +48,7 @@ void pci_host_common_remove(struct platform_device *pdev);
 
 struct pci_config_window *pci_host_common_ecam_create(struct device *dev,
 	struct pci_host_bridge *bridge, const struct pci_ecam_ops *ops);
+
+bool pci_host_common_d3cold_possible(struct pci_host_bridge *bridge,
+				     bool *pme_capable);
 #endif

drivers/pci/pci.h

@@ -1094,6 +1094,7 @@ void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked);
 void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
 void pci_configure_ltr(struct pci_dev *pdev);
 void pci_bridge_reconfigure_ltr(struct pci_dev *pdev);
+void pcie_encode_t_power_on(u32 t_power_on_us, u8 *scale, u8 *value);
 #else
 static inline void pcie_aspm_remove_cap(struct pci_dev *pdev, u32 lnkcap) { }
 static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { }
@@ -1102,6 +1103,11 @@ static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked)
 static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
 static inline void pci_configure_ltr(struct pci_dev *pdev) { }
 static inline void pci_bridge_reconfigure_ltr(struct pci_dev *pdev) { }
+static inline void pcie_encode_t_power_on(u32 t_power_on_us, u8 *scale, u8 *value)
+{
+	*scale = 0;
+	*value = 0;
+}
 #endif
 
 #ifdef CONFIG_PCIE_ECRC

drivers/pci/pcie/aspm.c

@@ -525,6 +525,46 @@ static u32 calc_l12_pwron(struct pci_dev *pdev, u32 scale, u32 val)
 	return 0;
 }
 
+/**
+ * pcie_encode_t_power_on - Encode T_POWER_ON into scale and value fields
+ * @t_power_on_us: T_POWER_ON time in microseconds
+ * @scale: Encoded T_POWER_ON Scale (0..2)
+ * @value: Encoded T_POWER_ON Value
+ *
+ * T_POWER_ON is encoded as:
+ *   T_POWER_ON(us) = scale_unit(us) * value
+ *
+ * where scale_unit is selected by @scale:
+ *   0: 2us
+ *   1: 10us
+ *   2: 100us
+ *
+ * If @t_power_on_us exceeds the maximum representable value, the result
+ * is clamped to the largest encodable T_POWER_ON.
+ *
+ * See PCIe r7.0, sec 7.8.3.2.
+ */
+void pcie_encode_t_power_on(u32 t_power_on_us, u8 *scale, u8 *value)
+{
+	u8 maxv = FIELD_MAX(PCI_L1SS_CAP_P_PWR_ON_VALUE);
+
+	/* T_POWER_ON_Value ("value") is a 5-bit field with max value of 31. */
+	if (t_power_on_us <= 2 * maxv) {
+		*scale = 0; /* Value times 2us */
+		*value = DIV_ROUND_UP(t_power_on_us, 2);
+	} else if (t_power_on_us <= 10 * maxv) {
+		*scale = 1; /* Value times 10us */
+		*value = DIV_ROUND_UP(t_power_on_us, 10);
+	} else if (t_power_on_us <= 100 * maxv) {
+		*scale = 2; /* value times 100us */
+		*value = DIV_ROUND_UP(t_power_on_us, 100);
+	} else {
+		*scale = 2;
+		*value = maxv;
+	}
+}
+EXPORT_SYMBOL(pcie_encode_t_power_on);
+
 /*
  * Encode an LTR_L1.2_THRESHOLD value for the L1 PM Substates Control 1
  * register.  Ports enter L1.2 when the most recent LTR value is greater