Merge branch 'pci/host/brcmstb'

- Declare bitmap correctly for use by bitmap interfaces (Christophe
  JAILLET)

- Clean up computation of legacy and non-legacy MSI bitmasks (Florian
  Fainelli)

- Update suspend/resume/remove error handling to warn about errors and not
  fail the operation (Jim Quinlan)

- Correct the "pcie" and "msi" interrupt descriptions in DT binding (Jim
  Quinlan)

- Add DT bindings for endpoint voltage regulators (Jim Quinlan)

- Split brcm_pcie_setup() into two functions (Jim Quinlan)

- Add mechanism for turning on voltage regulators for connected devices
  (Jim Quinlan)

- Turn voltage regulators for connected devices on/off when bus is added or
  removed (Jim Quinlan)

- When suspending, don't turn off voltage regulators for wakeup devices
  (Jim Quinlan)

* pci/host/brcmstb:
  PCI: brcmstb: Do not turn off WOL regulators on suspend
  PCI: brcmstb: Add control of subdevice voltage regulators
  PCI: brcmstb: Add mechanism to turn on subdev regulators
  PCI: brcmstb: Split brcm_pcie_setup() into two funcs
  dt-bindings: PCI: Add bindings for Brcmstb EP voltage regulators
  dt-bindings: PCI: Correct brcmstb interrupts, interrupt-map.
  PCI: brcmstb: Fix function return value handling
  PCI: brcmstb: Do not use __GENMASK
  PCI: brcmstb: Declare 'used' as bitmap, not unsigned long

1 files changed, 263 insertions, 41 deletions

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 1fc7bd49a7ad..1cba6e668150 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -24,6 +24,7 @@
 #include <linux/pci.h>
 #include <linux/pci-ecam.h>
 #include <linux/printk.h>
+#include <linux/regulator/consumer.h>
 #include <linux/reset.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
@@ -144,6 +145,9 @@
 #define BRCM_INT_PCI_MSI_NR		32
 #define BRCM_INT_PCI_MSI_LEGACY_NR	8
 #define BRCM_INT_PCI_MSI_SHIFT		0
+#define BRCM_INT_PCI_MSI_MASK		GENMASK(BRCM_INT_PCI_MSI_NR - 1, 0)
+#define BRCM_INT_PCI_MSI_LEGACY_MASK	GENMASK(31, \
+						32 - BRCM_INT_PCI_MSI_LEGACY_NR)
 
 /* MSI target addresses */
 #define BRCM_MSI_TARGET_ADDR_LT_4GB	0x0fffffffcULL
@@ -191,6 +195,8 @@ static inline void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie,
 static inline void brcm_pcie_perst_set_4908(struct brcm_pcie *pcie, u32 val);
 static inline void brcm_pcie_perst_set_7278(struct brcm_pcie *pcie, u32 val);
 static inline void brcm_pcie_perst_set_generic(struct brcm_pcie *pcie, u32 val);
+static int brcm_pcie_linkup(struct brcm_pcie *pcie);
+static int brcm_pcie_add_bus(struct pci_bus *bus);
 
 enum {
 	RGR1_SW_INIT_1,
@@ -257,6 +263,14 @@ static const struct pcie_cfg_data bcm2711_cfg = {
 	.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,
 };
 
+struct subdev_regulators {
+	unsigned int num_supplies;
+	struct regulator_bulk_data supplies[];
+};
+
+static int pci_subdev_regulators_add_bus(struct pci_bus *bus);
+static void pci_subdev_regulators_remove_bus(struct pci_bus *bus);
+
 struct brcm_msi {
 	struct device		*dev;
 	void __iomem		*base;
@@ -266,8 +280,7 @@ struct brcm_msi {
 	struct mutex		lock; /* guards the alloc/free operations */
 	u64			target_addr;
 	int			irq;
-	/* used indicates which MSI interrupts have been alloc'd */
-	unsigned long		used;
+	DECLARE_BITMAP(used, BRCM_INT_PCI_MSI_NR);
 	bool			legacy;
 	/* Some chips have MSIs in bits [31..24] of a shared register. */
 	int			legacy_shift;
@@ -295,6 +308,9 @@ struct brcm_pcie {
 	u32			hw_rev;
 	void			(*perst_set)(struct brcm_pcie *pcie, u32 val);
 	void			(*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
+	bool			refusal_mode;
+	struct subdev_regulators *sr;
+	bool			ep_wakeup_capable;
 };
 
 /*
@@ -406,6 +422,99 @@ static int brcm_pcie_set_ssc(struct brcm_pcie *pcie)
 	return ssc && pll ? 0 : -EIO;
 }
 
+static void *alloc_subdev_regulators(struct device *dev)
+{
+	static const char * const supplies[] = {
+		"vpcie3v3",
+		"vpcie3v3aux",
+		"vpcie12v",
+	};
+	const size_t size = sizeof(struct subdev_regulators)
+		+ sizeof(struct regulator_bulk_data) * ARRAY_SIZE(supplies);
+	struct subdev_regulators *sr;
+	int i;
+
+	sr = devm_kzalloc(dev, size, GFP_KERNEL);
+	if (sr) {
+		sr->num_supplies = ARRAY_SIZE(supplies);
+		for (i = 0; i < ARRAY_SIZE(supplies); i++)
+			sr->supplies[i].supply = supplies[i];
+	}
+
+	return sr;
+}
+
+static int pci_subdev_regulators_add_bus(struct pci_bus *bus)
+{
+	struct device *dev = &bus->dev;
+	struct subdev_regulators *sr;
+	int ret;
+
+	if (!dev->of_node || !bus->parent || !pci_is_root_bus(bus->parent))
+		return 0;
+
+	if (dev->driver_data)
+		dev_err(dev, "dev.driver_data unexpectedly non-NULL\n");
+
+	sr = alloc_subdev_regulators(dev);
+	if (!sr)
+		return -ENOMEM;
+
+	dev->driver_data = sr;
+	ret = regulator_bulk_get(dev, sr->num_supplies, sr->supplies);
+	if (ret)
+		return ret;
+
+	ret = regulator_bulk_enable(sr->num_supplies, sr->supplies);
+	if (ret) {
+		dev_err(dev, "failed to enable regulators for downstream device\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int brcm_pcie_add_bus(struct pci_bus *bus)
+{
+	struct device *dev = &bus->dev;
+	struct brcm_pcie *pcie = (struct brcm_pcie *) bus->sysdata;
+	int ret;
+
+	if (!dev->of_node || !bus->parent || !pci_is_root_bus(bus->parent))
+		return 0;
+
+	ret = pci_subdev_regulators_add_bus(bus);
+	if (ret)
+		return ret;
+
+	/* Grab the regulators for suspend/resume */
+	pcie->sr = bus->dev.driver_data;
+
+	/*
+	 * If we have failed linkup there is no point to return an error as
+	 * currently it will cause a WARNING() from pci_alloc_child_bus().
+	 * We return 0 and turn on the "refusal_mode" so that any further
+	 * accesses to the pci_dev just get 0xffffffff
+	 */
+	if (brcm_pcie_linkup(pcie) != 0)
+		pcie->refusal_mode = true;
+
+	return 0;
+}
+
+static void pci_subdev_regulators_remove_bus(struct pci_bus *bus)
+{
+	struct device *dev = &bus->dev;
+	struct subdev_regulators *sr = dev->driver_data;
+
+	if (!sr || !bus->parent || !pci_is_root_bus(bus->parent))
+		return;
+
+	if (regulator_bulk_disable(sr->num_supplies, sr->supplies))
+		dev_err(dev, "failed to disable regulators for downstream device\n");
+	dev->driver_data = NULL;
+}
+
 /* Limits operation to a specific generation (1, 2, or 3) */
 static void brcm_pcie_set_gen(struct brcm_pcie *pcie, int gen)
 {
@@ -534,7 +643,7 @@ static int brcm_msi_alloc(struct brcm_msi *msi)
 	int hwirq;
 
 	mutex_lock(&msi->lock);
-	hwirq = bitmap_find_free_region(&msi->used, msi->nr, 0);
+	hwirq = bitmap_find_free_region(msi->used, msi->nr, 0);
 	mutex_unlock(&msi->lock);
 
 	return hwirq;
@@ -543,7 +652,7 @@ static int brcm_msi_alloc(struct brcm_msi *msi)
 static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq)
 {
 	mutex_lock(&msi->lock);
-	bitmap_release_region(&msi->used, hwirq, 0);
+	bitmap_release_region(msi->used, hwirq, 0);
 	mutex_unlock(&msi->lock);
 }
 
@@ -619,7 +728,8 @@ static void brcm_msi_remove(struct brcm_pcie *pcie)
 
 static void brcm_msi_set_regs(struct brcm_msi *msi)
 {
-	u32 val = __GENMASK(31, msi->legacy_shift);
+	u32 val = msi->legacy ? BRCM_INT_PCI_MSI_LEGACY_MASK :
+				BRCM_INT_PCI_MSI_MASK;
 
 	writel(val, msi->intr_base + MSI_INT_MASK_CLR);
 	writel(val, msi->intr_base + MSI_INT_CLR);
@@ -661,6 +771,12 @@ static int brcm_pcie_enable_msi(struct brcm_pcie *pcie)
 	msi->irq = irq;
 	msi->legacy = pcie->hw_rev < BRCM_PCIE_HW_REV_33;
 
+	/*
+	 * Sanity check to make sure that the 'used' bitmap in struct brcm_msi
+	 * is large enough.
+	 */
+	BUILD_BUG_ON(BRCM_INT_PCI_MSI_LEGACY_NR > BRCM_INT_PCI_MSI_NR);
+
 	if (msi->legacy) {
 		msi->intr_base = msi->base + PCIE_INTR2_CPU_BASE;
 		msi->nr = BRCM_INT_PCI_MSI_LEGACY_NR;
@@ -711,6 +827,18 @@ static void __iomem *brcm_pcie_map_conf(struct pci_bus *bus, unsigned int devfn,
 	/* Accesses to the RC go right to the RC registers if slot==0 */
 	if (pci_is_root_bus(bus))
 		return PCI_SLOT(devfn) ? NULL : base + where;
+	if (pcie->refusal_mode) {
+		/*
+		 * At this point we do not have link.  There will be a CPU
+		 * abort -- a quirk with this controller --if Linux tries
+		 * to read any config-space registers besides those
+		 * targeting the host bridge.  To prevent this we hijack
+		 * the address to point to a safe access that will return
+		 * 0xffffffff.
+		 */
+		writel(0xffffffff, base + PCIE_MISC_RC_BAR2_CONFIG_HI);
+		return base + PCIE_MISC_RC_BAR2_CONFIG_HI + (where & 0x3);
+	}
 
 	/* For devices, write to the config space index register */
 	idx = PCIE_ECAM_OFFSET(bus->number, devfn, 0);
@@ -722,6 +850,8 @@ static struct pci_ops brcm_pcie_ops = {
 	.map_bus = brcm_pcie_map_conf,
 	.read = pci_generic_config_read,
 	.write = pci_generic_config_write,
+	.add_bus = brcm_pcie_add_bus,
+	.remove_bus = pci_subdev_regulators_remove_bus,
 };
 
 static inline void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie, u32 val)
@@ -863,16 +993,9 @@ static inline int brcm_pcie_get_rc_bar2_size_and_offset(struct brcm_pcie *pcie,
 
 static int brcm_pcie_setup(struct brcm_pcie *pcie)
 {
-	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
 	u64 rc_bar2_offset, rc_bar2_size;
 	void __iomem *base = pcie->base;
-	struct device *dev = pcie->dev;
-	struct resource_entry *entry;
-	bool ssc_good = false;
-	struct resource *res;
-	int num_out_wins = 0;
-	u16 nlw, cls, lnksta;
-	int i, ret, memc;
+	int ret, memc;
 	u32 tmp, burst, aspm_support;
 
 	/* Reset the bridge */
@@ -957,6 +1080,40 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
 	if (pcie->gen)
 		brcm_pcie_set_gen(pcie, pcie->gen);
 
+	/* Don't advertise L0s capability if 'aspm-no-l0s' */
+	aspm_support = PCIE_LINK_STATE_L1;
+	if (!of_property_read_bool(pcie->np, "aspm-no-l0s"))
+		aspm_support |= PCIE_LINK_STATE_L0S;
+	tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
+	u32p_replace_bits(&tmp, aspm_support,
+		PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK);
+	writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
+
+	/*
+	 * For config space accesses on the RC, show the right class for
+	 * a PCIe-PCIe bridge (the default setting is to be EP mode).
+	 */
+	tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
+	u32p_replace_bits(&tmp, 0x060400,
+			  PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
+	writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
+
+	return 0;
+}
+
+static int brcm_pcie_linkup(struct brcm_pcie *pcie)
+{
+	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
+	struct device *dev = pcie->dev;
+	void __iomem *base = pcie->base;
+	struct resource_entry *entry;
+	struct resource *res;
+	int num_out_wins = 0;
+	u16 nlw, cls, lnksta;
+	bool ssc_good = false;
+	u32 tmp;
+	int ret, i;
+
 	/* Unassert the fundamental reset */
 	pcie->perst_set(pcie, 0);
 
@@ -994,24 +1151,6 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
 		num_out_wins++;
 	}
 
-	/* Don't advertise L0s capability if 'aspm-no-l0s' */
-	aspm_support = PCIE_LINK_STATE_L1;
-	if (!of_property_read_bool(pcie->np, "aspm-no-l0s"))
-		aspm_support |= PCIE_LINK_STATE_L0S;
-	tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
-	u32p_replace_bits(&tmp, aspm_support,
-		PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK);
-	writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
-
-	/*
-	 * For config space accesses on the RC, show the right class for
-	 * a PCIe-PCIe bridge (the default setting is to be EP mode).
-	 */
-	tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
-	u32p_replace_bits(&tmp, 0x060400,
-			  PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
-	writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
-
 	if (pcie->ssc) {
 		ret = brcm_pcie_set_ssc(pcie);
 		if (ret == 0)
@@ -1140,17 +1279,60 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie)
 	pcie->bridge_sw_init_set(pcie, 1);
 }
 
+static int pci_dev_may_wakeup(struct pci_dev *dev, void *data)
+{
+	bool *ret = data;
+
+	if (device_may_wakeup(&dev->dev)) {
+		*ret = true;
+		dev_info(&dev->dev, "disable cancelled for wake-up device\n");
+	}
+	return (int) *ret;
+}
+
 static int brcm_pcie_suspend(struct device *dev)
 {
 	struct brcm_pcie *pcie = dev_get_drvdata(dev);
+	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
 	int ret;
 
 	brcm_pcie_turn_off(pcie);
-	ret = brcm_phy_stop(pcie);
-	reset_control_rearm(pcie->rescal);
+	/*
+	 * If brcm_phy_stop() returns an error, just dev_err(). If we
+	 * return the error it will cause the suspend to fail and this is a
+	 * forgivable offense that will probably be erased on resume.
+	 */
+	if (brcm_phy_stop(pcie))
+		dev_err(dev, "Could not stop phy for suspend\n");
+
+	ret = reset_control_rearm(pcie->rescal);
+	if (ret) {
+		dev_err(dev, "Could not rearm rescal reset\n");
+		return ret;
+	}
+
+	if (pcie->sr) {
+		/*
+		 * Now turn off the regulators, but if at least one
+		 * downstream device is enabled as a wake-up source, do not
+		 * turn off regulators.
+		 */
+		pcie->ep_wakeup_capable = false;
+		pci_walk_bus(bridge->bus, pci_dev_may_wakeup,
+			     &pcie->ep_wakeup_capable);
+		if (!pcie->ep_wakeup_capable) {
+			ret = regulator_bulk_disable(pcie->sr->num_supplies,
+						     pcie->sr->supplies);
+			if (ret) {
+				dev_err(dev, "Could not turn off regulators\n");
+				reset_control_reset(pcie->rescal);
+				return ret;
+			}
+		}
+	}
 	clk_disable_unprepare(pcie->clk);
 
-	return ret;
+	return 0;
 }
 
 static int brcm_pcie_resume(struct device *dev)
@@ -1161,11 +1343,32 @@ static int brcm_pcie_resume(struct device *dev)
 	int ret;
 
 	base = pcie->base;
-	clk_prepare_enable(pcie->clk);
+	ret = clk_prepare_enable(pcie->clk);
+	if (ret)
+		return ret;
+
+	if (pcie->sr) {
+		if (pcie->ep_wakeup_capable) {
+			/*
+			 * We are resuming from a suspend.  In the suspend we
+			 * did not disable the power supplies, so there is
+			 * no need to enable them (and falsely increase their
+			 * usage count).
+			 */
+			pcie->ep_wakeup_capable = false;
+		} else {
+			ret = regulator_bulk_enable(pcie->sr->num_supplies,
+						    pcie->sr->supplies);
+			if (ret) {
+				dev_err(dev, "Could not turn on regulators\n");
+				goto err_disable_clk;
+			}
+		}
+	}
 
 	ret = reset_control_reset(pcie->rescal);
 	if (ret)
-		goto err_disable_clk;
+		goto err_regulator;
 
 	ret = brcm_phy_start(pcie);
 	if (ret)
@@ -1186,6 +1389,10 @@ static int brcm_pcie_resume(struct device *dev)
 	if (ret)
 		goto err_reset;
 
+	ret = brcm_pcie_linkup(pcie);
+	if (ret)
+		goto err_reset;
+
 	if (pcie->msi)
 		brcm_msi_set_regs(pcie->msi);
 
@@ -1193,6 +1400,9 @@ static int brcm_pcie_resume(struct device *dev)
 
 err_reset:
 	reset_control_rearm(pcie->rescal);
+err_regulator:
+	if (pcie->sr)
+		regulator_bulk_disable(pcie->sr->num_supplies, pcie->sr->supplies);
 err_disable_clk:
 	clk_disable_unprepare(pcie->clk);
 	return ret;
@@ -1202,8 +1412,10 @@ static void __brcm_pcie_remove(struct brcm_pcie *pcie)
 {
 	brcm_msi_remove(pcie);
 	brcm_pcie_turn_off(pcie);
-	brcm_phy_stop(pcie);
-	reset_control_rearm(pcie->rescal);
+	if (brcm_phy_stop(pcie))
+		dev_err(pcie->dev, "Could not stop phy\n");
+	if (reset_control_rearm(pcie->rescal))
+		dev_err(pcie->dev, "Could not rearm rescal reset\n");
 	clk_disable_unprepare(pcie->clk);
 }
 
@@ -1320,7 +1532,17 @@ static int brcm_pcie_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, pcie);
 
-	return pci_host_probe(bridge);
+	ret = pci_host_probe(bridge);
+	if (!ret && !brcm_pcie_link_up(pcie))
+		ret = -ENODEV;
+
+	if (ret) {
+		brcm_pcie_remove(pdev);
+		return ret;
+	}
+
+	return 0;
+
 fail:
 	__brcm_pcie_remove(pcie);
 	return ret;
@@ -1329,8 +1551,8 @@ fail:
 MODULE_DEVICE_TABLE(of, brcm_pcie_match);
 
 static const struct dev_pm_ops brcm_pcie_pm_ops = {
-	.suspend = brcm_pcie_suspend,
-	.resume = brcm_pcie_resume,
+	.suspend_noirq = brcm_pcie_suspend,
+	.resume_noirq = brcm_pcie_resume,
 };
 
 static struct platform_driver brcm_pcie_driver = {