Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 332 insertions, 0 deletions

diff --git a/drivers/phy/qualcomm/phy-qcom-pcie2.c b/drivers/phy/qualcomm/phy-qcom-pcie2.c
new file mode 100644
index 000000000..11a2bb958
--- /dev/null
+++ b/drivers/phy/qualcomm/phy-qcom-pcie2.c
@@ -0,0 +1,332 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2014-2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2019, Linaro Ltd.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/phy/phy.h>
+
+#define PCIE20_PARF_PHY_STTS         0x3c
+#define PCIE2_PHY_RESET_CTRL         0x44
+#define PCIE20_PARF_PHY_REFCLK_CTRL2 0xa0
+#define PCIE20_PARF_PHY_REFCLK_CTRL3 0xa4
+#define PCIE20_PARF_PCS_SWING_CTRL1  0x88
+#define PCIE20_PARF_PCS_SWING_CTRL2  0x8c
+#define PCIE20_PARF_PCS_DEEMPH1      0x74
+#define PCIE20_PARF_PCS_DEEMPH2      0x78
+#define PCIE20_PARF_PCS_DEEMPH3      0x7c
+#define PCIE20_PARF_CONFIGBITS       0x84
+#define PCIE20_PARF_PHY_CTRL3        0x94
+#define PCIE20_PARF_PCS_CTRL         0x80
+
+#define TX_AMP_VAL                   120
+#define PHY_RX0_EQ_GEN1_VAL          0
+#define PHY_RX0_EQ_GEN2_VAL          4
+#define TX_DEEMPH_GEN1_VAL           24
+#define TX_DEEMPH_GEN2_3_5DB_VAL     26
+#define TX_DEEMPH_GEN2_6DB_VAL       36
+#define PHY_TX0_TERM_OFFST_VAL       0
+
+struct qcom_phy {
+	struct device *dev;
+	void __iomem *base;
+
+	struct regulator_bulk_data vregs[2];
+
+	struct reset_control *phy_reset;
+	struct reset_control *pipe_reset;
+	struct clk *pipe_clk;
+};
+
+static int qcom_pcie2_phy_init(struct phy *phy)
+{
+	struct qcom_phy *qphy = phy_get_drvdata(phy);
+	int ret;
+
+	ret = reset_control_deassert(qphy->phy_reset);
+	if (ret) {
+		dev_err(qphy->dev, "cannot deassert pipe reset\n");
+		return ret;
+	}
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(qphy->vregs), qphy->vregs);
+	if (ret)
+		reset_control_assert(qphy->phy_reset);
+
+	return ret;
+}
+
+static int qcom_pcie2_phy_power_on(struct phy *phy)
+{
+	struct qcom_phy *qphy = phy_get_drvdata(phy);
+	int ret;
+	u32 val;
+
+	/* Program REF_CLK source */
+	val = readl(qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2);
+	val &= ~BIT(1);
+	writel(val, qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2);
+
+	usleep_range(1000, 2000);
+
+	/* Don't use PAD for refclock */
+	val = readl(qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2);
+	val &= ~BIT(0);
+	writel(val, qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL2);
+
+	/* Program SSP ENABLE */
+	val = readl(qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL3);
+	val |= BIT(0);
+	writel(val, qphy->base + PCIE20_PARF_PHY_REFCLK_CTRL3);
+
+	usleep_range(1000, 2000);
+
+	/* Assert Phy SW Reset */
+	val = readl(qphy->base + PCIE2_PHY_RESET_CTRL);
+	val |= BIT(0);
+	writel(val, qphy->base + PCIE2_PHY_RESET_CTRL);
+
+	/* Program Tx Amplitude */
+	val = readl(qphy->base + PCIE20_PARF_PCS_SWING_CTRL1);
+	val &= ~0x7f;
+	val |= TX_AMP_VAL;
+	writel(val, qphy->base + PCIE20_PARF_PCS_SWING_CTRL1);
+
+	val = readl(qphy->base + PCIE20_PARF_PCS_SWING_CTRL2);
+	val &= ~0x7f;
+	val |= TX_AMP_VAL;
+	writel(val, qphy->base + PCIE20_PARF_PCS_SWING_CTRL2);
+
+	/* Program De-Emphasis */
+	val = readl(qphy->base + PCIE20_PARF_PCS_DEEMPH1);
+	val &= ~0x3f;
+	val |= TX_DEEMPH_GEN2_6DB_VAL;
+	writel(val, qphy->base + PCIE20_PARF_PCS_DEEMPH1);
+
+	val = readl(qphy->base + PCIE20_PARF_PCS_DEEMPH2);
+	val &= ~0x3f;
+	val |= TX_DEEMPH_GEN2_3_5DB_VAL;
+	writel(val, qphy->base + PCIE20_PARF_PCS_DEEMPH2);
+
+	val = readl(qphy->base + PCIE20_PARF_PCS_DEEMPH3);
+	val &= ~0x3f;
+	val |= TX_DEEMPH_GEN1_VAL;
+	writel(val, qphy->base + PCIE20_PARF_PCS_DEEMPH3);
+
+	/* Program Rx_Eq */
+	val = readl(qphy->base + PCIE20_PARF_CONFIGBITS);
+	val &= ~0x7;
+	val |= PHY_RX0_EQ_GEN2_VAL;
+	writel(val, qphy->base + PCIE20_PARF_CONFIGBITS);
+
+	/* Program Tx0_term_offset */
+	val = readl(qphy->base + PCIE20_PARF_PHY_CTRL3);
+	val &= ~0x1f;
+	val |= PHY_TX0_TERM_OFFST_VAL;
+	writel(val, qphy->base + PCIE20_PARF_PHY_CTRL3);
+
+	/* disable Tx2Rx Loopback */
+	val = readl(qphy->base + PCIE20_PARF_PCS_CTRL);
+	val &= ~BIT(1);
+	writel(val, qphy->base + PCIE20_PARF_PCS_CTRL);
+
+	/* De-assert Phy SW Reset */
+	val = readl(qphy->base + PCIE2_PHY_RESET_CTRL);
+	val &= ~BIT(0);
+	writel(val, qphy->base + PCIE2_PHY_RESET_CTRL);
+
+	usleep_range(1000, 2000);
+
+	ret = reset_control_deassert(qphy->pipe_reset);
+	if (ret) {
+		dev_err(qphy->dev, "cannot deassert pipe reset\n");
+		goto out;
+	}
+
+	clk_set_rate(qphy->pipe_clk, 250000000);
+
+	ret = clk_prepare_enable(qphy->pipe_clk);
+	if (ret) {
+		dev_err(qphy->dev, "failed to enable pipe clock\n");
+		goto out;
+	}
+
+	ret = readl_poll_timeout(qphy->base + PCIE20_PARF_PHY_STTS, val,
+				 !(val & BIT(0)), 1000, 10);
+	if (ret)
+		dev_err(qphy->dev, "phy initialization failed\n");
+
+out:
+	return ret;
+}
+
+static int qcom_pcie2_phy_power_off(struct phy *phy)
+{
+	struct qcom_phy *qphy = phy_get_drvdata(phy);
+	u32 val;
+
+	val = readl(qphy->base + PCIE2_PHY_RESET_CTRL);
+	val |= BIT(0);
+	writel(val, qphy->base + PCIE2_PHY_RESET_CTRL);
+
+	clk_disable_unprepare(qphy->pipe_clk);
+	reset_control_assert(qphy->pipe_reset);
+
+	return 0;
+}
+
+static int qcom_pcie2_phy_exit(struct phy *phy)
+{
+	struct qcom_phy *qphy = phy_get_drvdata(phy);
+
+	regulator_bulk_disable(ARRAY_SIZE(qphy->vregs), qphy->vregs);
+	reset_control_assert(qphy->phy_reset);
+
+	return 0;
+}
+
+static const struct phy_ops qcom_pcie2_ops = {
+	.init = qcom_pcie2_phy_init,
+	.power_on = qcom_pcie2_phy_power_on,
+	.power_off = qcom_pcie2_phy_power_off,
+	.exit = qcom_pcie2_phy_exit,
+	.owner = THIS_MODULE,
+};
+
+/*
+ * Register a fixed rate pipe clock.
+ *
+ * The <s>_pipe_clksrc generated by PHY goes to the GCC that gate
+ * controls it. The <s>_pipe_clk coming out of the GCC is requested
+ * by the PHY driver for its operations.
+ * We register the <s>_pipe_clksrc here. The gcc driver takes care
+ * of assigning this <s>_pipe_clksrc as parent to <s>_pipe_clk.
+ * Below picture shows this relationship.
+ *
+ *         +---------------+
+ *         |   PHY block   |<<---------------------------------------+
+ *         |               |                                         |
+ *         |   +-------+   |                   +-----+               |
+ *   I/P---^-->|  PLL  |---^--->pipe_clksrc--->| GCC |--->pipe_clk---+
+ *    clk  |   +-------+   |                   +-----+
+ *         +---------------+
+ */
+static int phy_pipe_clksrc_register(struct qcom_phy *qphy)
+{
+	struct device_node *np = qphy->dev->of_node;
+	struct clk_fixed_rate *fixed;
+	struct clk_init_data init = { };
+	int ret;
+
+	ret = of_property_read_string(np, "clock-output-names", &init.name);
+	if (ret) {
+		dev_err(qphy->dev, "%s: No clock-output-names\n", np->name);
+		return ret;
+	}
+
+	fixed = devm_kzalloc(qphy->dev, sizeof(*fixed), GFP_KERNEL);
+	if (!fixed)
+		return -ENOMEM;
+
+	init.ops = &clk_fixed_rate_ops;
+
+	/* controllers using QMP phys use 250MHz pipe clock interface */
+	fixed->fixed_rate = 250000000;
+	fixed->hw.init = &init;
+
+	ret = devm_clk_hw_register(qphy->dev, &fixed->hw);
+	if (ret < 0)
+		return ret;
+
+	return devm_of_clk_add_hw_provider(qphy->dev, of_clk_hw_simple_get, &fixed->hw);
+}
+
+static int qcom_pcie2_phy_probe(struct platform_device *pdev)
+{
+	struct phy_provider *phy_provider;
+	struct qcom_phy *qphy;
+	struct device *dev = &pdev->dev;
+	struct phy *phy;
+	int ret;
+
+	qphy = devm_kzalloc(dev, sizeof(*qphy), GFP_KERNEL);
+	if (!qphy)
+		return -ENOMEM;
+
+	qphy->dev = dev;
+	qphy->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(qphy->base))
+		return PTR_ERR(qphy->base);
+
+	ret = phy_pipe_clksrc_register(qphy);
+	if (ret) {
+		dev_err(dev, "failed to register pipe_clk\n");
+		return ret;
+	}
+
+	qphy->vregs[0].supply = "vdda-vp";
+	qphy->vregs[1].supply = "vdda-vph";
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(qphy->vregs), qphy->vregs);
+	if (ret < 0)
+		return ret;
+
+	qphy->pipe_clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(qphy->pipe_clk)) {
+		dev_err(dev, "failed to acquire pipe clock\n");
+		return PTR_ERR(qphy->pipe_clk);
+	}
+
+	qphy->phy_reset = devm_reset_control_get_exclusive(dev, "phy");
+	if (IS_ERR(qphy->phy_reset)) {
+		dev_err(dev, "failed to acquire phy reset\n");
+		return PTR_ERR(qphy->phy_reset);
+	}
+
+	qphy->pipe_reset = devm_reset_control_get_exclusive(dev, "pipe");
+	if (IS_ERR(qphy->pipe_reset)) {
+		dev_err(dev, "failed to acquire pipe reset\n");
+		return PTR_ERR(qphy->pipe_reset);
+	}
+
+	phy = devm_phy_create(dev, dev->of_node, &qcom_pcie2_ops);
+	if (IS_ERR(phy)) {
+		dev_err(dev, "failed to create phy\n");
+		return PTR_ERR(phy);
+	}
+
+	phy_set_drvdata(phy, qphy);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+	if (IS_ERR(phy_provider))
+		dev_err(dev, "failed to register phy provider\n");
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id qcom_pcie2_phy_match_table[] = {
+	{ .compatible = "qcom,pcie2-phy" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, qcom_pcie2_phy_match_table);
+
+static struct platform_driver qcom_pcie2_phy_driver = {
+	.probe = qcom_pcie2_phy_probe,
+	.driver = {
+		.name = "phy-qcom-pcie2",
+		.of_match_table = qcom_pcie2_phy_match_table,
+	},
+};
+
+module_platform_driver(qcom_pcie2_phy_driver);
+
+MODULE_DESCRIPTION("Qualcomm PCIe PHY driver");
+MODULE_LICENSE("GPL v2");