Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 456 insertions, 0 deletions

diff --git a/drivers/devfreq/imx8m-ddrc.c b/drivers/devfreq/imx8m-ddrc.c
new file mode 100644
index 000000000..52beeb5b7
--- /dev/null
+++ b/drivers/devfreq/imx8m-ddrc.c
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/devfreq.h>
+#include <linux/pm_opp.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/arm-smccc.h>
+
+#define IMX_SIP_DDR_DVFS			0xc2000004
+
+/* Query available frequencies. */
+#define IMX_SIP_DDR_DVFS_GET_FREQ_COUNT		0x10
+#define IMX_SIP_DDR_DVFS_GET_FREQ_INFO		0x11
+
+/*
+ * This should be in a 1:1 mapping with devicetree OPPs but
+ * firmware provides additional info.
+ */
+struct imx8m_ddrc_freq {
+	unsigned long rate;
+	unsigned long smcarg;
+	int dram_core_parent_index;
+	int dram_alt_parent_index;
+	int dram_apb_parent_index;
+};
+
+/* Hardware limitation */
+#define IMX8M_DDRC_MAX_FREQ_COUNT 4
+
+/*
+ * i.MX8M DRAM Controller clocks have the following structure (abridged):
+ *
+ * +----------+       |\            +------+
+ * | dram_pll |-------|M| dram_core |      |
+ * +----------+       |U|---------->| D    |
+ *                 /--|X|           |  D   |
+ *   dram_alt_root |  |/            |   R  |
+ *                 |                |    C |
+ *            +---------+           |      |
+ *            |FIX DIV/4|           |      |
+ *            +---------+           |      |
+ *  composite:     |                |      |
+ * +----------+    |                |      |
+ * | dram_alt |----/                |      |
+ * +----------+                     |      |
+ * | dram_apb |-------------------->|      |
+ * +----------+                     +------+
+ *
+ * The dram_pll is used for higher rates and dram_alt is used for lower rates.
+ *
+ * Frequency switching is implemented in TF-A (via SMC call) and can change the
+ * configuration of the clocks, including mux parents. The dram_alt and
+ * dram_apb clocks are "imx composite" and their parent can change too.
+ *
+ * We need to prepare/enable the new mux parents head of switching and update
+ * their information afterwards.
+ */
+struct imx8m_ddrc {
+	struct devfreq_dev_profile profile;
+	struct devfreq *devfreq;
+
+	/* For frequency switching: */
+	struct clk *dram_core;
+	struct clk *dram_pll;
+	struct clk *dram_alt;
+	struct clk *dram_apb;
+
+	int freq_count;
+	struct imx8m_ddrc_freq freq_table[IMX8M_DDRC_MAX_FREQ_COUNT];
+};
+
+static struct imx8m_ddrc_freq *imx8m_ddrc_find_freq(struct imx8m_ddrc *priv,
+						    unsigned long rate)
+{
+	struct imx8m_ddrc_freq *freq;
+	int i;
+
+	/*
+	 * Firmware reports values in MT/s, so we round-down from Hz
+	 * Rounding is extra generous to ensure a match.
+	 */
+	rate = DIV_ROUND_CLOSEST(rate, 250000);
+	for (i = 0; i < priv->freq_count; ++i) {
+		freq = &priv->freq_table[i];
+		if (freq->rate == rate ||
+				freq->rate + 1 == rate ||
+				freq->rate - 1 == rate)
+			return freq;
+	}
+
+	return NULL;
+}
+
+static void imx8m_ddrc_smc_set_freq(int target_freq)
+{
+	struct arm_smccc_res res;
+	u32 online_cpus = 0;
+	int cpu;
+
+	local_irq_disable();
+
+	for_each_online_cpu(cpu)
+		online_cpus |= (1 << (cpu * 8));
+
+	/* change the ddr freqency */
+	arm_smccc_smc(IMX_SIP_DDR_DVFS, target_freq, online_cpus,
+			0, 0, 0, 0, 0, &res);
+
+	local_irq_enable();
+}
+
+static struct clk *clk_get_parent_by_index(struct clk *clk, int index)
+{
+	struct clk_hw *hw;
+
+	hw = clk_hw_get_parent_by_index(__clk_get_hw(clk), index);
+
+	return hw ? hw->clk : NULL;
+}
+
+static int imx8m_ddrc_set_freq(struct device *dev, struct imx8m_ddrc_freq *freq)
+{
+	struct imx8m_ddrc *priv = dev_get_drvdata(dev);
+	struct clk *new_dram_core_parent;
+	struct clk *new_dram_alt_parent;
+	struct clk *new_dram_apb_parent;
+	int ret;
+
+	/*
+	 * Fetch new parents
+	 *
+	 * new_dram_alt_parent and new_dram_apb_parent are optional but
+	 * new_dram_core_parent is not.
+	 */
+	new_dram_core_parent = clk_get_parent_by_index(
+			priv->dram_core, freq->dram_core_parent_index - 1);
+	if (!new_dram_core_parent) {
+		dev_err(dev, "failed to fetch new dram_core parent\n");
+		return -EINVAL;
+	}
+	if (freq->dram_alt_parent_index) {
+		new_dram_alt_parent = clk_get_parent_by_index(
+				priv->dram_alt,
+				freq->dram_alt_parent_index - 1);
+		if (!new_dram_alt_parent) {
+			dev_err(dev, "failed to fetch new dram_alt parent\n");
+			return -EINVAL;
+		}
+	} else
+		new_dram_alt_parent = NULL;
+
+	if (freq->dram_apb_parent_index) {
+		new_dram_apb_parent = clk_get_parent_by_index(
+				priv->dram_apb,
+				freq->dram_apb_parent_index - 1);
+		if (!new_dram_apb_parent) {
+			dev_err(dev, "failed to fetch new dram_apb parent\n");
+			return -EINVAL;
+		}
+	} else
+		new_dram_apb_parent = NULL;
+
+	/* increase reference counts and ensure clks are ON before switch */
+	ret = clk_prepare_enable(new_dram_core_parent);
+	if (ret) {
+		dev_err(dev, "failed to enable new dram_core parent: %d\n",
+			ret);
+		goto out;
+	}
+	ret = clk_prepare_enable(new_dram_alt_parent);
+	if (ret) {
+		dev_err(dev, "failed to enable new dram_alt parent: %d\n",
+			ret);
+		goto out_disable_core_parent;
+	}
+	ret = clk_prepare_enable(new_dram_apb_parent);
+	if (ret) {
+		dev_err(dev, "failed to enable new dram_apb parent: %d\n",
+			ret);
+		goto out_disable_alt_parent;
+	}
+
+	imx8m_ddrc_smc_set_freq(freq->smcarg);
+
+	/* update parents in clk tree after switch. */
+	ret = clk_set_parent(priv->dram_core, new_dram_core_parent);
+	if (ret)
+		dev_warn(dev, "failed to set dram_core parent: %d\n", ret);
+	if (new_dram_alt_parent) {
+		ret = clk_set_parent(priv->dram_alt, new_dram_alt_parent);
+		if (ret)
+			dev_warn(dev, "failed to set dram_alt parent: %d\n",
+				 ret);
+	}
+	if (new_dram_apb_parent) {
+		ret = clk_set_parent(priv->dram_apb, new_dram_apb_parent);
+		if (ret)
+			dev_warn(dev, "failed to set dram_apb parent: %d\n",
+				 ret);
+	}
+
+	/*
+	 * Explicitly refresh dram PLL rate.
+	 *
+	 * Even if it's marked with CLK_GET_RATE_NOCACHE the rate will not be
+	 * automatically refreshed when clk_get_rate is called on children.
+	 */
+	clk_get_rate(priv->dram_pll);
+
+	/*
+	 * clk_set_parent transfer the reference count from old parent.
+	 * now we drop extra reference counts used during the switch
+	 */
+	clk_disable_unprepare(new_dram_apb_parent);
+out_disable_alt_parent:
+	clk_disable_unprepare(new_dram_alt_parent);
+out_disable_core_parent:
+	clk_disable_unprepare(new_dram_core_parent);
+out:
+	return ret;
+}
+
+static int imx8m_ddrc_target(struct device *dev, unsigned long *freq, u32 flags)
+{
+	struct imx8m_ddrc *priv = dev_get_drvdata(dev);
+	struct imx8m_ddrc_freq *freq_info;
+	struct dev_pm_opp *new_opp;
+	unsigned long old_freq, new_freq;
+	int ret;
+
+	new_opp = devfreq_recommended_opp(dev, freq, flags);
+	if (IS_ERR(new_opp)) {
+		ret = PTR_ERR(new_opp);
+		dev_err(dev, "failed to get recommended opp: %d\n", ret);
+		return ret;
+	}
+	dev_pm_opp_put(new_opp);
+
+	old_freq = clk_get_rate(priv->dram_core);
+	if (*freq == old_freq)
+		return 0;
+
+	freq_info = imx8m_ddrc_find_freq(priv, *freq);
+	if (!freq_info)
+		return -EINVAL;
+
+	/*
+	 * Read back the clk rate to verify switch was correct and so that
+	 * we can report it on all error paths.
+	 */
+	ret = imx8m_ddrc_set_freq(dev, freq_info);
+
+	new_freq = clk_get_rate(priv->dram_core);
+	if (ret)
+		dev_err(dev, "ddrc failed freq switch to %lu from %lu: error %d. now at %lu\n",
+			*freq, old_freq, ret, new_freq);
+	else if (*freq != new_freq)
+		dev_err(dev, "ddrc failed freq update to %lu from %lu, now at %lu\n",
+			*freq, old_freq, new_freq);
+	else
+		dev_dbg(dev, "ddrc freq set to %lu (was %lu)\n",
+			*freq, old_freq);
+
+	return ret;
+}
+
+static int imx8m_ddrc_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+	struct imx8m_ddrc *priv = dev_get_drvdata(dev);
+
+	*freq = clk_get_rate(priv->dram_core);
+
+	return 0;
+}
+
+static int imx8m_ddrc_init_freq_info(struct device *dev)
+{
+	struct imx8m_ddrc *priv = dev_get_drvdata(dev);
+	struct arm_smccc_res res;
+	int index;
+
+	/* An error here means DDR DVFS API not supported by firmware */
+	arm_smccc_smc(IMX_SIP_DDR_DVFS, IMX_SIP_DDR_DVFS_GET_FREQ_COUNT,
+			0, 0, 0, 0, 0, 0, &res);
+	priv->freq_count = res.a0;
+	if (priv->freq_count <= 0 ||
+			priv->freq_count > IMX8M_DDRC_MAX_FREQ_COUNT)
+		return -ENODEV;
+
+	for (index = 0; index < priv->freq_count; ++index) {
+		struct imx8m_ddrc_freq *freq = &priv->freq_table[index];
+
+		arm_smccc_smc(IMX_SIP_DDR_DVFS, IMX_SIP_DDR_DVFS_GET_FREQ_INFO,
+			      index, 0, 0, 0, 0, 0, &res);
+		/* Result should be strictly positive */
+		if ((long)res.a0 <= 0)
+			return -ENODEV;
+
+		freq->rate = res.a0;
+		freq->smcarg = index;
+		freq->dram_core_parent_index = res.a1;
+		freq->dram_alt_parent_index = res.a2;
+		freq->dram_apb_parent_index = res.a3;
+
+		/* dram_core has 2 options: dram_pll or dram_alt_root */
+		if (freq->dram_core_parent_index != 1 &&
+				freq->dram_core_parent_index != 2)
+			return -ENODEV;
+		/* dram_apb and dram_alt have exactly 8 possible parents */
+		if (freq->dram_alt_parent_index > 8 ||
+				freq->dram_apb_parent_index > 8)
+			return -ENODEV;
+		/* dram_core from alt requires explicit dram_alt parent */
+		if (freq->dram_core_parent_index == 2 &&
+				freq->dram_alt_parent_index == 0)
+			return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int imx8m_ddrc_check_opps(struct device *dev)
+{
+	struct imx8m_ddrc *priv = dev_get_drvdata(dev);
+	struct imx8m_ddrc_freq *freq_info;
+	struct dev_pm_opp *opp;
+	unsigned long freq;
+	int i, opp_count;
+
+	/* Enumerate DT OPPs and disable those not supported by firmware */
+	opp_count = dev_pm_opp_get_opp_count(dev);
+	if (opp_count < 0)
+		return opp_count;
+	for (i = 0, freq = 0; i < opp_count; ++i, ++freq) {
+		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
+		if (IS_ERR(opp)) {
+			dev_err(dev, "Failed enumerating OPPs: %ld\n",
+				PTR_ERR(opp));
+			return PTR_ERR(opp);
+		}
+		dev_pm_opp_put(opp);
+
+		freq_info = imx8m_ddrc_find_freq(priv, freq);
+		if (!freq_info) {
+			dev_info(dev, "Disable unsupported OPP %luHz %luMT/s\n",
+					freq, DIV_ROUND_CLOSEST(freq, 250000));
+			dev_pm_opp_disable(dev, freq);
+		}
+	}
+
+	return 0;
+}
+
+static void imx8m_ddrc_exit(struct device *dev)
+{
+	dev_pm_opp_of_remove_table(dev);
+}
+
+static int imx8m_ddrc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct imx8m_ddrc *priv;
+	const char *gov = DEVFREQ_GOV_USERSPACE;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, priv);
+
+	ret = imx8m_ddrc_init_freq_info(dev);
+	if (ret) {
+		dev_err(dev, "failed to init firmware freq info: %d\n", ret);
+		return ret;
+	}
+
+	priv->dram_core = devm_clk_get(dev, "core");
+	if (IS_ERR(priv->dram_core)) {
+		ret = PTR_ERR(priv->dram_core);
+		dev_err(dev, "failed to fetch core clock: %d\n", ret);
+		return ret;
+	}
+	priv->dram_pll = devm_clk_get(dev, "pll");
+	if (IS_ERR(priv->dram_pll)) {
+		ret = PTR_ERR(priv->dram_pll);
+		dev_err(dev, "failed to fetch pll clock: %d\n", ret);
+		return ret;
+	}
+	priv->dram_alt = devm_clk_get(dev, "alt");
+	if (IS_ERR(priv->dram_alt)) {
+		ret = PTR_ERR(priv->dram_alt);
+		dev_err(dev, "failed to fetch alt clock: %d\n", ret);
+		return ret;
+	}
+	priv->dram_apb = devm_clk_get(dev, "apb");
+	if (IS_ERR(priv->dram_apb)) {
+		ret = PTR_ERR(priv->dram_apb);
+		dev_err(dev, "failed to fetch apb clock: %d\n", ret);
+		return ret;
+	}
+
+	ret = dev_pm_opp_of_add_table(dev);
+	if (ret < 0) {
+		dev_err(dev, "failed to get OPP table\n");
+		return ret;
+	}
+
+	ret = imx8m_ddrc_check_opps(dev);
+	if (ret < 0)
+		goto err;
+
+	priv->profile.target = imx8m_ddrc_target;
+	priv->profile.exit = imx8m_ddrc_exit;
+	priv->profile.get_cur_freq = imx8m_ddrc_get_cur_freq;
+	priv->profile.initial_freq = clk_get_rate(priv->dram_core);
+
+	priv->devfreq = devm_devfreq_add_device(dev, &priv->profile,
+						gov, NULL);
+	if (IS_ERR(priv->devfreq)) {
+		ret = PTR_ERR(priv->devfreq);
+		dev_err(dev, "failed to add devfreq device: %d\n", ret);
+		goto err;
+	}
+
+	return 0;
+
+err:
+	dev_pm_opp_of_remove_table(dev);
+	return ret;
+}
+
+static const struct of_device_id imx8m_ddrc_of_match[] = {
+	{ .compatible = "fsl,imx8m-ddrc", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, imx8m_ddrc_of_match);
+
+static struct platform_driver imx8m_ddrc_platdrv = {
+	.probe		= imx8m_ddrc_probe,
+	.driver = {
+		.name	= "imx8m-ddrc-devfreq",
+		.of_match_table = imx8m_ddrc_of_match,
+	},
+};
+module_platform_driver(imx8m_ddrc_platdrv);
+
+MODULE_DESCRIPTION("i.MX8M DDR Controller frequency driver");
+MODULE_AUTHOR("Leonard Crestez <leonard.crestez@nxp.com>");
+MODULE_LICENSE("GPL v2");