1 files changed, 480 insertions, 0 deletions
diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
new file mode 100644
index 000000000000..5f885196f4d0
--- /dev/null
+++ b/drivers/soc/qcom/qcom_aoss.c
@@ -0,0 +1,480 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019, Linaro Ltd
+ */
+#include <dt-bindings/power/qcom-aoss-qmp.h>
+#include <linux/clk-provider.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+
+#define QMP_DESC_MAGIC			0x0
+#define QMP_DESC_VERSION		0x4
+#define QMP_DESC_FEATURES		0x8
+
+/* AOP-side offsets */
+#define QMP_DESC_UCORE_LINK_STATE	0xc
+#define QMP_DESC_UCORE_LINK_STATE_ACK	0x10
+#define QMP_DESC_UCORE_CH_STATE		0x14
+#define QMP_DESC_UCORE_CH_STATE_ACK	0x18
+#define QMP_DESC_UCORE_MBOX_SIZE	0x1c
+#define QMP_DESC_UCORE_MBOX_OFFSET	0x20
+
+/* Linux-side offsets */
+#define QMP_DESC_MCORE_LINK_STATE	0x24
+#define QMP_DESC_MCORE_LINK_STATE_ACK	0x28
+#define QMP_DESC_MCORE_CH_STATE		0x2c
+#define QMP_DESC_MCORE_CH_STATE_ACK	0x30
+#define QMP_DESC_MCORE_MBOX_SIZE	0x34
+#define QMP_DESC_MCORE_MBOX_OFFSET	0x38
+
+#define QMP_STATE_UP			GENMASK(15, 0)
+#define QMP_STATE_DOWN			GENMASK(31, 16)
+
+#define QMP_MAGIC			0x4d41494c /* mail */
+#define QMP_VERSION			1
+
+/* 64 bytes is enough to store the requests and provides padding to 4 bytes */
+#define QMP_MSG_LEN			64
+
+/**
+ * struct qmp - driver state for QMP implementation
+ * @msgram: iomem referencing the message RAM used for communication
+ * @dev: reference to QMP device
+ * @mbox_client: mailbox client used to ring the doorbell on transmit
+ * @mbox_chan: mailbox channel used to ring the doorbell on transmit
+ * @offset: offset within @msgram where messages should be written
+ * @size: maximum size of the messages to be transmitted
+ * @event: wait_queue for synchronization with the IRQ
+ * @tx_lock: provides synchronization between multiple callers of qmp_send()
+ * @qdss_clk: QDSS clock hw struct
+ * @pd_data: genpd data
+ */
+struct qmp {
+	void __iomem *msgram;
+	struct device *dev;
+
+	struct mbox_client mbox_client;
+	struct mbox_chan *mbox_chan;
+
+	size_t offset;
+	size_t size;
+
+	wait_queue_head_t event;
+
+	struct mutex tx_lock;
+
+	struct clk_hw qdss_clk;
+	struct genpd_onecell_data pd_data;
+};
+
+struct qmp_pd {
+	struct qmp *qmp;
+	struct generic_pm_domain pd;
+};
+
+#define to_qmp_pd_resource(res) container_of(res, struct qmp_pd, pd)
+
+static void qmp_kick(struct qmp *qmp)
+{
+	mbox_send_message(qmp->mbox_chan, NULL);
+	mbox_client_txdone(qmp->mbox_chan, 0);
+}
+
+static bool qmp_magic_valid(struct qmp *qmp)
+{
+	return readl(qmp->msgram + QMP_DESC_MAGIC) == QMP_MAGIC;
+}
+
+static bool qmp_link_acked(struct qmp *qmp)
+{
+	return readl(qmp->msgram + QMP_DESC_MCORE_LINK_STATE_ACK) == QMP_STATE_UP;
+}
+
+static bool qmp_mcore_channel_acked(struct qmp *qmp)
+{
+	return readl(qmp->msgram + QMP_DESC_MCORE_CH_STATE_ACK) == QMP_STATE_UP;
+}
+
+static bool qmp_ucore_channel_up(struct qmp *qmp)
+{
+	return readl(qmp->msgram + QMP_DESC_UCORE_CH_STATE) == QMP_STATE_UP;
+}
+
+static int qmp_open(struct qmp *qmp)
+{
+	int ret;
+	u32 val;
+
+	if (!qmp_magic_valid(qmp)) {
+		dev_err(qmp->dev, "QMP magic doesn't match\n");
+		return -EINVAL;
+	}
+
+	val = readl(qmp->msgram + QMP_DESC_VERSION);
+	if (val != QMP_VERSION) {
+		dev_err(qmp->dev, "unsupported QMP version %d\n", val);
+		return -EINVAL;
+	}
+
+	qmp->offset = readl(qmp->msgram + QMP_DESC_MCORE_MBOX_OFFSET);
+	qmp->size = readl(qmp->msgram + QMP_DESC_MCORE_MBOX_SIZE);
+	if (!qmp->size) {
+		dev_err(qmp->dev, "invalid mailbox size\n");
+		return -EINVAL;
+	}
+
+	/* Ack remote core's link state */
+	val = readl(qmp->msgram + QMP_DESC_UCORE_LINK_STATE);
+	writel(val, qmp->msgram + QMP_DESC_UCORE_LINK_STATE_ACK);
+
+	/* Set local core's link state to up */
+	writel(QMP_STATE_UP, qmp->msgram + QMP_DESC_MCORE_LINK_STATE);
+
+	qmp_kick(qmp);
+
+	ret = wait_event_timeout(qmp->event, qmp_link_acked(qmp), HZ);
+	if (!ret) {
+		dev_err(qmp->dev, "ucore didn't ack link\n");
+		goto timeout_close_link;
+	}
+
+	writel(QMP_STATE_UP, qmp->msgram + QMP_DESC_MCORE_CH_STATE);
+
+	qmp_kick(qmp);
+
+	ret = wait_event_timeout(qmp->event, qmp_ucore_channel_up(qmp), HZ);
+	if (!ret) {
+		dev_err(qmp->dev, "ucore didn't open channel\n");
+		goto timeout_close_channel;
+	}
+
+	/* Ack remote core's channel state */
+	writel(QMP_STATE_UP, qmp->msgram + QMP_DESC_UCORE_CH_STATE_ACK);
+
+	qmp_kick(qmp);
+
+	ret = wait_event_timeout(qmp->event, qmp_mcore_channel_acked(qmp), HZ);
+	if (!ret) {
+		dev_err(qmp->dev, "ucore didn't ack channel\n");
+		goto timeout_close_channel;
+	}
+
+	return 0;
+
+timeout_close_channel:
+	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_CH_STATE);
+
+timeout_close_link:
+	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_LINK_STATE);
+	qmp_kick(qmp);
+
+	return -ETIMEDOUT;
+}
+
+static void qmp_close(struct qmp *qmp)
+{
+	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_CH_STATE);
+	writel(QMP_STATE_DOWN, qmp->msgram + QMP_DESC_MCORE_LINK_STATE);
+	qmp_kick(qmp);
+}
+
+static irqreturn_t qmp_intr(int irq, void *data)
+{
+	struct qmp *qmp = data;
+
+	wake_up_interruptible_all(&qmp->event);
+
+	return IRQ_HANDLED;
+}
+
+static bool qmp_message_empty(struct qmp *qmp)
+{
+	return readl(qmp->msgram + qmp->offset) == 0;
+}
+
+/**
+ * qmp_send() - send a message to the AOSS
+ * @qmp: qmp context
+ * @data: message to be sent
+ * @len: length of the message
+ *
+ * Transmit @data to AOSS and wait for the AOSS to acknowledge the message.
+ * @len must be a multiple of 4 and not longer than the mailbox size. Access is
+ * synchronized by this implementation.
+ *
+ * Return: 0 on success, negative errno on failure
+ */
+static int qmp_send(struct qmp *qmp, const void *data, size_t len)
+{
+	long time_left;
+	int ret;
+
+	if (WARN_ON(len + sizeof(u32) > qmp->size))
+		return -EINVAL;
+
+	if (WARN_ON(len % sizeof(u32)))
+		return -EINVAL;
+
+	mutex_lock(&qmp->tx_lock);
+
+	/* The message RAM only implements 32-bit accesses */
+	__iowrite32_copy(qmp->msgram + qmp->offset + sizeof(u32),
+			 data, len / sizeof(u32));
+	writel(len, qmp->msgram + qmp->offset);
+	qmp_kick(qmp);
+
+	time_left = wait_event_interruptible_timeout(qmp->event,
+						     qmp_message_empty(qmp), HZ);
+	if (!time_left) {
+		dev_err(qmp->dev, "ucore did not ack channel\n");
+		ret = -ETIMEDOUT;
+
+		/* Clear message from buffer */
+		writel(0, qmp->msgram + qmp->offset);
+	} else {
+		ret = 0;
+	}
+
+	mutex_unlock(&qmp->tx_lock);
+
+	return ret;
+}
+
+static int qmp_qdss_clk_prepare(struct clk_hw *hw)
+{
+	static const char buf[QMP_MSG_LEN] = "{class: clock, res: qdss, val: 1}";
+	struct qmp *qmp = container_of(hw, struct qmp, qdss_clk);
+
+	return qmp_send(qmp, buf, sizeof(buf));
+}
+
+static void qmp_qdss_clk_unprepare(struct clk_hw *hw)
+{
+	static const char buf[QMP_MSG_LEN] = "{class: clock, res: qdss, val: 0}";
+	struct qmp *qmp = container_of(hw, struct qmp, qdss_clk);
+
+	qmp_send(qmp, buf, sizeof(buf));
+}
+
+static const struct clk_ops qmp_qdss_clk_ops = {
+	.prepare = qmp_qdss_clk_prepare,
+	.unprepare = qmp_qdss_clk_unprepare,
+};
+
+static int qmp_qdss_clk_add(struct qmp *qmp)
+{
+	static const struct clk_init_data qdss_init = {
+		.ops = &qmp_qdss_clk_ops,
+		.name = "qdss",
+	};
+	int ret;
+
+	qmp->qdss_clk.init = &qdss_init;
+	ret = clk_hw_register(qmp->dev, &qmp->qdss_clk);
+	if (ret < 0) {
+		dev_err(qmp->dev, "failed to register qdss clock\n");
+		return ret;
+	}
+
+	ret = of_clk_add_hw_provider(qmp->dev->of_node, of_clk_hw_simple_get,
+				     &qmp->qdss_clk);
+	if (ret < 0) {
+		dev_err(qmp->dev, "unable to register of clk hw provider\n");
+		clk_hw_unregister(&qmp->qdss_clk);
+	}
+
+	return ret;
+}
+
+static void qmp_qdss_clk_remove(struct qmp *qmp)
+{
+	of_clk_del_provider(qmp->dev->of_node);
+	clk_hw_unregister(&qmp->qdss_clk);
+}
+
+static int qmp_pd_power_toggle(struct qmp_pd *res, bool enable)
+{
+	char buf[QMP_MSG_LEN] = {};
+
+	snprintf(buf, sizeof(buf),
+		 "{class: image, res: load_state, name: %s, val: %s}",
+		 res->pd.name, enable ? "on" : "off");
+	return qmp_send(res->qmp, buf, sizeof(buf));
+}
+
+static int qmp_pd_power_on(struct generic_pm_domain *domain)
+{
+	return qmp_pd_power_toggle(to_qmp_pd_resource(domain), true);
+}
+
+static int qmp_pd_power_off(struct generic_pm_domain *domain)
+{
+	return qmp_pd_power_toggle(to_qmp_pd_resource(domain), false);
+}
+
+static const char * const sdm845_resources[] = {
+	[AOSS_QMP_LS_CDSP] = "cdsp",
+	[AOSS_QMP_LS_LPASS] = "adsp",
+	[AOSS_QMP_LS_MODEM] = "modem",
+	[AOSS_QMP_LS_SLPI] = "slpi",
+	[AOSS_QMP_LS_SPSS] = "spss",
+	[AOSS_QMP_LS_VENUS] = "venus",
+};
+
+static int qmp_pd_add(struct qmp *qmp)
+{
+	struct genpd_onecell_data *data = &qmp->pd_data;
+	struct device *dev = qmp->dev;
+	struct qmp_pd *res;
+	size_t num = ARRAY_SIZE(sdm845_resources);
+	int ret;
+	int i;
+
+	res = devm_kcalloc(dev, num, sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return -ENOMEM;
+
+	data->domains = devm_kcalloc(dev, num, sizeof(*data->domains),
+				     GFP_KERNEL);
+	if (!data->domains)
+		return -ENOMEM;
+
+	for (i = 0; i < num; i++) {
+		res[i].qmp = qmp;
+		res[i].pd.name = sdm845_resources[i];
+		res[i].pd.power_on = qmp_pd_power_on;
+		res[i].pd.power_off = qmp_pd_power_off;
+
+		ret = pm_genpd_init(&res[i].pd, NULL, true);
+		if (ret < 0) {
+			dev_err(dev, "failed to init genpd\n");
+			goto unroll_genpds;
+		}
+
+		data->domains[i] = &res[i].pd;
+	}
+
+	data->num_domains = i;
+
+	ret = of_genpd_add_provider_onecell(dev->of_node, data);
+	if (ret < 0)
+		goto unroll_genpds;
+
+	return 0;
+
+unroll_genpds:
+	for (i--; i >= 0; i--)
+		pm_genpd_remove(data->domains[i]);
+
+	return ret;
+}
+
+static void qmp_pd_remove(struct qmp *qmp)
+{
+	struct genpd_onecell_data *data = &qmp->pd_data;
+	struct device *dev = qmp->dev;
+	int i;
+
+	of_genpd_del_provider(dev->of_node);
+
+	for (i = 0; i < data->num_domains; i++)
+		pm_genpd_remove(data->domains[i]);
+}
+
+static int qmp_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct qmp *qmp;
+	int irq;
+	int ret;
+
+	qmp = devm_kzalloc(&pdev->dev, sizeof(*qmp), GFP_KERNEL);
+	if (!qmp)
+		return -ENOMEM;
+
+	qmp->dev = &pdev->dev;
+	init_waitqueue_head(&qmp->event);
+	mutex_init(&qmp->tx_lock);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	qmp->msgram = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(qmp->msgram))
+		return PTR_ERR(qmp->msgram);
+
+	qmp->mbox_client.dev = &pdev->dev;
+	qmp->mbox_client.knows_txdone = true;
+	qmp->mbox_chan = mbox_request_channel(&qmp->mbox_client, 0);
+	if (IS_ERR(qmp->mbox_chan)) {
+		dev_err(&pdev->dev, "failed to acquire ipc mailbox\n");
+		return PTR_ERR(qmp->mbox_chan);
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	ret = devm_request_irq(&pdev->dev, irq, qmp_intr, IRQF_ONESHOT,
+			       "aoss-qmp", qmp);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to request interrupt\n");
+		goto err_free_mbox;
+	}
+
+	ret = qmp_open(qmp);
+	if (ret < 0)
+		goto err_free_mbox;
+
+	ret = qmp_qdss_clk_add(qmp);
+	if (ret)
+		goto err_close_qmp;
+
+	ret = qmp_pd_add(qmp);
+	if (ret)
+		goto err_remove_qdss_clk;
+
+	platform_set_drvdata(pdev, qmp);
+
+	return 0;
+
+err_remove_qdss_clk:
+	qmp_qdss_clk_remove(qmp);
+err_close_qmp:
+	qmp_close(qmp);
+err_free_mbox:
+	mbox_free_channel(qmp->mbox_chan);
+
+	return ret;
+}
+
+static int qmp_remove(struct platform_device *pdev)
+{
+	struct qmp *qmp = platform_get_drvdata(pdev);
+
+	qmp_qdss_clk_remove(qmp);
+	qmp_pd_remove(qmp);
+
+	qmp_close(qmp);
+	mbox_free_channel(qmp->mbox_chan);
+
+	return 0;
+}
+
+static const struct of_device_id qmp_dt_match[] = {
+	{ .compatible = "qcom,sdm845-aoss-qmp", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, qmp_dt_match);
+
+static struct platform_driver qmp_driver = {
+	.driver = {
+		.name		= "qcom_aoss_qmp",
+		.of_match_table	= qmp_dt_match,
+	},
+	.probe = qmp_probe,
+	.remove	= qmp_remove,
+};
+module_platform_driver(qmp_driver);
+
+MODULE_DESCRIPTION("Qualcomm AOSS QMP driver");
+MODULE_LICENSE("GPL v2");