The AOSS QMP driver is used to communicate with the AOSS for certain side-channel requests, that are not enabled through the RPMh interface. The communication is a very simple synchronous mechanism of messages being written in message RAM and a doorbell in the AOSS is rung. As the AOSS has processed the message length is cleared and an interrupt is fired by the AOSS as acknowledgment. Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> --- Changes since v1: - Skip check in send for empty TX buffer - Don't follow WARN_ON() with dev_err() - Register platform_device rather than populate based on of-children drivers/soc/qcom/Kconfig | 9 + drivers/soc/qcom/Makefile | 1 + drivers/soc/qcom/aoss-qmp.c | 313 ++++++++++++++++++++++++++++++ include/linux/soc/qcom/aoss-qmp.h | 12 ++ 4 files changed, 335 insertions(+) create mode 100644 drivers/soc/qcom/aoss-qmp.c create mode 100644 include/linux/soc/qcom/aoss-qmp.h diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig index a51458022d21..dda19471057f 100644 --- a/drivers/soc/qcom/Kconfig +++ b/drivers/soc/qcom/Kconfig @@ -3,6 +3,15 @@ # menu "Qualcomm SoC drivers" +config QCOM_AOSS_QMP + tristate "Qualcomm AOSS Messaging Driver" + depends on ARCH_QCOM || COMPILE_TEST + depends on MAILBOX + help + This driver provides the means for communicating with the + micro-controller in the AOSS, using QMP, to control certain resource + that are not exposed through RPMh. + config QCOM_COMMAND_DB bool "Qualcomm Command DB" depends on ARCH_QCOM || COMPILE_TEST diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile index 67cb85d0373c..d0d7fdc94d9a 100644 --- a/drivers/soc/qcom/Makefile +++ b/drivers/soc/qcom/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 CFLAGS_rpmh-rsc.o := -I$(src) +obj-$(CONFIG_QCOM_AOSS_QMP) += aoss-qmp.o obj-$(CONFIG_QCOM_GENI_SE) += qcom-geni-se.o obj-$(CONFIG_QCOM_COMMAND_DB) += cmd-db.o obj-$(CONFIG_QCOM_GLINK_SSR) += glink_ssr.o diff --git a/drivers/soc/qcom/aoss-qmp.c b/drivers/soc/qcom/aoss-qmp.c new file mode 100644 index 000000000000..de52703b96b6 --- /dev/null +++ b/drivers/soc/qcom/aoss-qmp.c @@ -0,0 +1,313 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018, Linaro Ltd + */ +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/soc/qcom/aoss-qmp.h> + +#define QMP_DESC_MAGIC 0x0 +#define QMP_DESC_VERSION 0x4 +#define QMP_DESC_FEATURES 0x8 + +#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 + +#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 0x0000ffff +#define QMP_STATE_DOWN 0xffff0000 + +#define QMP_MAGIC 0x4d41494c +#define QMP_VERSION 1 + +/** + * 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 syncrhonization between multiple callers of qmp_send() + * @pd_pdev: platform device for the power-domain child device + */ +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 platform_device *pd_pdev; +}; + +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; + + ret = wait_event_timeout(qmp->event, qmp_magic_valid(qmp), HZ); + if (!ret) { + dev_err(qmp->dev, "QMP magic doesn't match\n"); + return -ETIMEDOUT; + } + + 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 0x%zx\n", qmp->size); + 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); + + 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 */ + val = readl(qmp->msgram + QMP_DESC_UCORE_CH_STATE); + writel(val, 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 + */ +int qmp_send(struct qmp *qmp, const void *data, size_t len) +{ + 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); + + ret = wait_event_interruptible_timeout(qmp->event, + qmp_message_empty(qmp), HZ); + if (!ret) { + 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; +} +EXPORT_SYMBOL(qmp_send); + +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"); + return ret; + } + + ret = qmp_open(qmp); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, qmp); + + if (of_property_read_bool(pdev->dev.of_node, "#power-domain-cells")) { + qmp->pd_pdev = platform_device_register_data(&pdev->dev, + "aoss_qmp_pd", + PLATFORM_DEVID_NONE, + NULL, 0); + if (IS_ERR(qmp->pd_pdev)) + dev_err(&pdev->dev, "failed to register AOSS PD\n"); + } + + return 0; +} + +static int qmp_remove(struct platform_device *pdev) +{ + struct qmp *qmp = platform_get_drvdata(pdev); + + platform_device_unregister(qmp->pd_pdev); + + qmp_close(qmp); + + 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 = "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"); diff --git a/include/linux/soc/qcom/aoss-qmp.h b/include/linux/soc/qcom/aoss-qmp.h new file mode 100644 index 000000000000..32ccaa091a9f --- /dev/null +++ b/include/linux/soc/qcom/aoss-qmp.h @@ -0,0 +1,12 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2018, Linaro Ltd + */ +#ifndef __AOP_QMP_H__ +#define __AOP_QMP_H__ + +struct qmp; + +int qmp_send(struct qmp *qmp, const void *data, size_t len); + +#endif -- 2.18.0