--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * rWTM BIU Mailbox driver for Armada 37xx
+ *
+ * Author: Marek Behun <marek.behun@nic.cz>
+ */
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_controller.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/armada-37xx-rwtm-mailbox.h>
+
+#define DRIVER_NAME "armada-37xx-rwtm-mailbox"
+
+/* relative to rWTM BIU Mailbox Registers */
+#define RWTM_MBOX_PARAM(i) (0x0 + ((i) << 2))
+#define RWTM_MBOX_COMMAND 0x40
+#define RWTM_MBOX_RETURN_STATUS 0x80
+#define RWTM_MBOX_STATUS(i) (0x84 + ((i) << 2))
+#define RWTM_MBOX_FIFO_STATUS 0xc4
+#define FIFO_STS_RDY 0x100
+#define FIFO_STS_CNTR_MASK 0x7
+#define FIFO_STS_CNTR_MAX 4
+
+#define RWTM_HOST_INT_RESET 0xc8
+#define RWTM_HOST_INT_MASK 0xcc
+#define SP_CMD_COMPLETE BIT(0)
+#define SP_CMD_QUEUE_FULL_ACCESS BIT(17)
+#define SP_CMD_QUEUE_FULL BIT(18)
+
+struct a37xx_mbox {
+ struct device *dev;
+ struct mbox_controller controller;
+ void __iomem *base;
+ int irq;
+};
+
+static void a37xx_mbox_receive(struct mbox_chan *chan)
+{
+ struct a37xx_mbox *mbox = chan->con_priv;
+ struct armada_37xx_rwtm_rx_msg rx_msg;
+ int i;
+
+ rx_msg.retval = readl(mbox->base + RWTM_MBOX_RETURN_STATUS);
+ for (i = 0; i < 16; ++i)
+ rx_msg.status[i] = readl(mbox->base + RWTM_MBOX_STATUS(i));
+
+ mbox_chan_received_data(chan, &rx_msg);
+}
+
+static irqreturn_t a37xx_mbox_irq_handler(int irq, void *data)
+{
+ struct mbox_chan *chan = data;
+ struct a37xx_mbox *mbox = chan->con_priv;
+ u32 reg;
+
+ reg = readl(mbox->base + RWTM_HOST_INT_RESET);
+
+ if (reg & SP_CMD_COMPLETE)
+ a37xx_mbox_receive(chan);
+
+ if (reg & (SP_CMD_QUEUE_FULL_ACCESS | SP_CMD_QUEUE_FULL))
+ dev_err(mbox->dev, "Secure processor command queue full\n");
+
+ writel(reg, mbox->base + RWTM_HOST_INT_RESET);
+ if (reg)
+ mbox_chan_txdone(chan, 0);
+
+ return reg ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static int a37xx_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+ struct a37xx_mbox *mbox = chan->con_priv;
+ struct armada_37xx_rwtm_tx_msg *msg = data;
+ int i;
+ u32 reg;
+
+ if (!data)
+ return -EINVAL;
+
+ reg = readl(mbox->base + RWTM_MBOX_FIFO_STATUS);
+ if (!(reg & FIFO_STS_RDY))
+ dev_warn(mbox->dev, "Secure processor not ready\n");
+
+ if ((reg & FIFO_STS_CNTR_MASK) >= FIFO_STS_CNTR_MAX) {
+ dev_err(mbox->dev, "Secure processor command queue full\n");
+ return -EBUSY;
+ }
+
+ for (i = 0; i < 16; ++i)
+ writel(msg->args[i], mbox->base + RWTM_MBOX_PARAM(i));
+ writel(msg->command, mbox->base + RWTM_MBOX_COMMAND);
+
+ return 0;
+}
+
+static int a37xx_mbox_startup(struct mbox_chan *chan)
+{
+ struct a37xx_mbox *mbox = chan->con_priv;
+ u32 reg;
+ int ret;
+
+ ret = devm_request_irq(mbox->dev, mbox->irq, a37xx_mbox_irq_handler, 0,
+ DRIVER_NAME, chan);
+ if (ret < 0) {
+ dev_err(mbox->dev, "Cannot request irq\n");
+ return ret;
+ }
+
+ /* enable IRQ generation */
+ reg = readl(mbox->base + RWTM_HOST_INT_MASK);
+ reg &= ~(SP_CMD_COMPLETE | SP_CMD_QUEUE_FULL_ACCESS | SP_CMD_QUEUE_FULL);
+ writel(reg, mbox->base + RWTM_HOST_INT_MASK);
+
+ return 0;
+}
+
+static void a37xx_mbox_shutdown(struct mbox_chan *chan)
+{
+ u32 reg;
+ struct a37xx_mbox *mbox = chan->con_priv;
+
+ /* disable interrupt generation */
+ reg = readl(mbox->base + RWTM_HOST_INT_MASK);
+ reg |= SP_CMD_COMPLETE | SP_CMD_QUEUE_FULL_ACCESS | SP_CMD_QUEUE_FULL;
+ writel(reg, mbox->base + RWTM_HOST_INT_MASK);
+
+ devm_free_irq(mbox->dev, mbox->irq, chan);
+}
+
+static const struct mbox_chan_ops a37xx_mbox_ops = {
+ .send_data = a37xx_mbox_send_data,
+ .startup = a37xx_mbox_startup,
+ .shutdown = a37xx_mbox_shutdown,
+};
+
+static int armada_37xx_mbox_probe(struct platform_device *pdev)
+{
+ struct a37xx_mbox *mbox;
+ struct resource *regs;
+ struct mbox_chan *chans;
+ int ret;
+
+ mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL);
+ if (!mbox)
+ return -ENOMEM;
+
+ /* Allocated one channel */
+ chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL);
+ if (!chans)
+ return -ENOMEM;
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ mbox->base = devm_ioremap_resource(&pdev->dev, regs);
+ if (IS_ERR(mbox->base)) {
+ dev_err(&pdev->dev, "ioremap failed\n");
+ return PTR_ERR(mbox->base);
+ }
+
+ mbox->irq = platform_get_irq(pdev, 0);
+ if (mbox->irq < 0) {
+ dev_err(&pdev->dev, "Cannot get irq\n");
+ return mbox->irq;
+ }
+
+ mbox->dev = &pdev->dev;
+
+ /* Hardware supports only one channel. */
+ chans[0].con_priv = mbox;
+ mbox->controller.dev = mbox->dev;
+ mbox->controller.num_chans = 1;
+ mbox->controller.chans = chans;
+ mbox->controller.ops = &a37xx_mbox_ops;
+ mbox->controller.txdone_irq = true;
+
+ ret = mbox_controller_register(&mbox->controller);
+ if (ret) {
+ dev_err(&pdev->dev, "Could not register mailbox controller\n");
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, mbox);
+ return ret;
+}
+
+static int armada_37xx_mbox_remove(struct platform_device *pdev)
+{
+ struct a37xx_mbox *mbox = platform_get_drvdata(pdev);
+
+ if (!mbox)
+ return -EINVAL;
+
+ mbox_controller_unregister(&mbox->controller);
+
+ return 0;
+}
+
+static const struct of_device_id armada_37xx_mbox_match[] = {
+ { .compatible = "marvell,armada-3700-rwtm-mailbox" },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, armada_37xx_mbox_match);
+
+static struct platform_driver armada_37xx_mbox_driver = {
+ .probe = armada_37xx_mbox_probe,
+ .remove = armada_37xx_mbox_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = armada_37xx_mbox_match,
+ },
+};
+
+module_platform_driver(armada_37xx_mbox_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("rWTM BIU Mailbox driver for Armada 37xx");
+MODULE_AUTHOR("Marek Behun <marek.behun@nic.cz>");
projects / linux-2.6-microblaze.git / commitdiff