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, 284 insertions, 0 deletions

diff --git a/drivers/phy/intel/phy-intel-lgm-emmc.c b/drivers/phy/intel/phy-intel-lgm-emmc.c
new file mode 100644
index 000000000..703aeb122
--- /dev/null
+++ b/drivers/phy/intel/phy-intel-lgm-emmc.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel eMMC PHY driver
+ * Copyright (C) 2019 Intel, Corp.
+ */
+
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* eMMC phy register definitions */
+#define EMMC_PHYCTRL0_REG	0xa8
+#define DR_TY_MASK		GENMASK(30, 28)
+#define DR_TY_SHIFT(x)		(((x) << 28) & DR_TY_MASK)
+#define OTAPDLYENA		BIT(14)
+#define OTAPDLYSEL_MASK		GENMASK(13, 10)
+#define OTAPDLYSEL_SHIFT(x)	(((x) << 10) & OTAPDLYSEL_MASK)
+
+#define EMMC_PHYCTRL1_REG	0xac
+#define PDB_MASK		BIT(0)
+#define PDB_SHIFT(x)		(((x) << 0) & PDB_MASK)
+#define ENDLL_MASK		BIT(7)
+#define ENDLL_SHIFT(x)		(((x) << 7) & ENDLL_MASK)
+
+#define EMMC_PHYCTRL2_REG	0xb0
+#define FRQSEL_25M		0
+#define FRQSEL_50M		1
+#define FRQSEL_100M		2
+#define FRQSEL_150M		3
+#define FRQSEL_MASK		GENMASK(24, 22)
+#define FRQSEL_SHIFT(x)		(((x) << 22) & FRQSEL_MASK)
+
+#define EMMC_PHYSTAT_REG	0xbc
+#define CALDONE_MASK		BIT(9)
+#define DLLRDY_MASK		BIT(8)
+#define IS_CALDONE(x)	((x) & CALDONE_MASK)
+#define IS_DLLRDY(x)	((x) & DLLRDY_MASK)
+
+struct intel_emmc_phy {
+	struct regmap *syscfg;
+	struct clk *emmcclk;
+};
+
+static int intel_emmc_phy_power(struct phy *phy, bool on_off)
+{
+	struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+	unsigned int caldone;
+	unsigned int dllrdy;
+	unsigned int freqsel;
+	unsigned long rate;
+	int ret, quot;
+
+	/*
+	 * Keep phyctrl_pdb and phyctrl_endll low to allow
+	 * initialization of CALIO state M/C DFFs
+	 */
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL1_REG, PDB_MASK,
+				 PDB_SHIFT(0));
+	if (ret) {
+		dev_err(&phy->dev, "CALIO power down bar failed: %d\n", ret);
+		return ret;
+	}
+
+	/* Already finish power_off above */
+	if (!on_off)
+		return 0;
+
+	rate = clk_get_rate(priv->emmcclk);
+	quot = DIV_ROUND_CLOSEST(rate, 50000000);
+	if (quot > FRQSEL_150M)
+		dev_warn(&phy->dev, "Unsupported rate: %lu\n", rate);
+	freqsel = clamp_t(int, quot, FRQSEL_25M, FRQSEL_150M);
+
+	/*
+	 * According to the user manual, calpad calibration
+	 * cycle takes more than 2us without the minimal recommended
+	 * value, so we may need a little margin here
+	 */
+	udelay(5);
+
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL1_REG, PDB_MASK,
+				 PDB_SHIFT(1));
+	if (ret) {
+		dev_err(&phy->dev, "CALIO power down bar failed: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * According to the user manual, it asks driver to wait 5us for
+	 * calpad busy trimming. However it is documented that this value is
+	 * PVT(A.K.A process,voltage and temperature) relevant, so some
+	 * failure cases are found which indicates we should be more tolerant
+	 * to calpad busy trimming.
+	 */
+	ret = regmap_read_poll_timeout(priv->syscfg, EMMC_PHYSTAT_REG,
+				       caldone, IS_CALDONE(caldone),
+				       0, 50);
+	if (ret) {
+		dev_err(&phy->dev, "caldone failed, ret=%d\n", ret);
+		return ret;
+	}
+
+	/* Set the frequency of the DLL operation */
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL2_REG, FRQSEL_MASK,
+				 FRQSEL_SHIFT(freqsel));
+	if (ret) {
+		dev_err(&phy->dev, "set the frequency of dll failed:%d\n", ret);
+		return ret;
+	}
+
+	/* Turn on the DLL */
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL1_REG, ENDLL_MASK,
+				 ENDLL_SHIFT(1));
+	if (ret) {
+		dev_err(&phy->dev, "turn on the dll failed: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * After enabling analog DLL circuits docs say that we need 10.2 us if
+	 * our source clock is at 50 MHz and that lock time scales linearly
+	 * with clock speed.  If we are powering on the PHY and the card clock
+	 * is super slow (like 100 kHZ) this could take as long as 5.1 ms as
+	 * per the math: 10.2 us * (50000000 Hz / 100000 Hz) => 5.1 ms
+	 * Hopefully we won't be running at 100 kHz, but we should still make
+	 * sure we wait long enough.
+	 *
+	 * NOTE: There appear to be corner cases where the DLL seems to take
+	 * extra long to lock for reasons that aren't understood.  In some
+	 * extreme cases we've seen it take up to over 10ms (!).  We'll be
+	 * generous and give it 50ms.
+	 */
+	ret = regmap_read_poll_timeout(priv->syscfg,
+				       EMMC_PHYSTAT_REG,
+				       dllrdy, IS_DLLRDY(dllrdy),
+				       0, 50 * USEC_PER_MSEC);
+	if (ret) {
+		dev_err(&phy->dev, "dllrdy failed. ret=%d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int intel_emmc_phy_init(struct phy *phy)
+{
+	struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+
+	/*
+	 * We purposely get the clock here and not in probe to avoid the
+	 * circular dependency problem. We expect:
+	 * - PHY driver to probe
+	 * - SDHCI driver to start probe
+	 * - SDHCI driver to register it's clock
+	 * - SDHCI driver to get the PHY
+	 * - SDHCI driver to init the PHY
+	 *
+	 * The clock is optional, so upon any error just return it like
+	 * any other error to user.
+	 *
+	 */
+	priv->emmcclk = clk_get_optional(&phy->dev, "emmcclk");
+	if (IS_ERR(priv->emmcclk)) {
+		dev_err(&phy->dev, "ERROR: getting emmcclk\n");
+		return PTR_ERR(priv->emmcclk);
+	}
+
+	return 0;
+}
+
+static int intel_emmc_phy_exit(struct phy *phy)
+{
+	struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+
+	clk_put(priv->emmcclk);
+
+	return 0;
+}
+
+static int intel_emmc_phy_power_on(struct phy *phy)
+{
+	struct intel_emmc_phy *priv = phy_get_drvdata(phy);
+	int ret;
+
+	/* Drive impedance: 50 Ohm */
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL0_REG, DR_TY_MASK,
+				 DR_TY_SHIFT(6));
+	if (ret) {
+		dev_err(&phy->dev, "ERROR set drive-impednce-50ohm: %d\n", ret);
+		return ret;
+	}
+
+	/* Output tap delay: disable */
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL0_REG, OTAPDLYENA,
+				 0);
+	if (ret) {
+		dev_err(&phy->dev, "ERROR Set output tap delay : %d\n", ret);
+		return ret;
+	}
+
+	/* Output tap delay */
+	ret = regmap_update_bits(priv->syscfg, EMMC_PHYCTRL0_REG,
+				 OTAPDLYSEL_MASK, OTAPDLYSEL_SHIFT(4));
+	if (ret) {
+		dev_err(&phy->dev, "ERROR: output tap dly select: %d\n", ret);
+		return ret;
+	}
+
+	/* Power up eMMC phy analog blocks */
+	return intel_emmc_phy_power(phy, true);
+}
+
+static int intel_emmc_phy_power_off(struct phy *phy)
+{
+	/* Power down eMMC phy analog blocks */
+	return intel_emmc_phy_power(phy, false);
+}
+
+static const struct phy_ops ops = {
+	.init		= intel_emmc_phy_init,
+	.exit		= intel_emmc_phy_exit,
+	.power_on	= intel_emmc_phy_power_on,
+	.power_off	= intel_emmc_phy_power_off,
+	.owner		= THIS_MODULE,
+};
+
+static int intel_emmc_phy_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct intel_emmc_phy *priv;
+	struct phy *generic_phy;
+	struct phy_provider *phy_provider;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	/* Get eMMC phy (accessed via chiptop) regmap */
+	priv->syscfg = syscon_regmap_lookup_by_phandle(np, "intel,syscon");
+	if (IS_ERR(priv->syscfg)) {
+		dev_err(dev, "failed to find syscon\n");
+		return PTR_ERR(priv->syscfg);
+	}
+
+	generic_phy = devm_phy_create(dev, np, &ops);
+	if (IS_ERR(generic_phy)) {
+		dev_err(dev, "failed to create PHY\n");
+		return PTR_ERR(generic_phy);
+	}
+
+	phy_set_drvdata(generic_phy, priv);
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id intel_emmc_phy_dt_ids[] = {
+	{ .compatible = "intel,lgm-emmc-phy" },
+	{}
+};
+
+MODULE_DEVICE_TABLE(of, intel_emmc_phy_dt_ids);
+
+static struct platform_driver intel_emmc_driver = {
+	.probe		= intel_emmc_phy_probe,
+	.driver		= {
+		.name	= "intel-emmc-phy",
+		.of_match_table = intel_emmc_phy_dt_ids,
+	},
+};
+
+module_platform_driver(intel_emmc_driver);
+
+MODULE_AUTHOR("Peter Harliman Liem <peter.harliman.liem@intel.com>");
+MODULE_DESCRIPTION("Intel eMMC PHY driver");
+MODULE_LICENSE("GPL v2");