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authorBjorn Helgaas <bhelgaas@google.com>2022-01-13 18:57:46 +0300
committerBjorn Helgaas <bhelgaas@google.com>2022-01-13 18:57:46 +0300
commitc5f62d30e99cc0d111bfba9d33ed05d576b3f7ee (patch)
tree01fa3a34ded15dcf3188cdfce4ac91d3efd84e1d /drivers/pci
parent3164f27b5fd692ef6e0a5464b31534d09cc73949 (diff)
parent11ed8b8624b8085f706864b4addcd304b1e4fc38 (diff)
downloadlinux-c5f62d30e99cc0d111bfba9d33ed05d576b3f7ee.tar.xz
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
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/controller/pcie-brcmstb.c304
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 = {