From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
This driver adds support for the single mailbox channel of the MSS
system controller on the Microchip PolarFire SoC.
Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
---
drivers/mailbox/Kconfig | 12 ++
drivers/mailbox/Makefile | 2 +
drivers/mailbox/mailbox-mpfs.c | 296 +++++++++++++++++++++++++++++++++
3 files changed, 310 insertions(+)
create mode 100644 drivers/mailbox/mailbox-mpfs.c
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 05b1009e2820..4881a519683a 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -153,6 +153,18 @@ config MAILBOX_TEST
Test client to help with testing new Controller driver
implementations.
+config MPFS_MBOX
+ tristate "MPFS Mailbox"
+ depends on HAS_IOMEM
+ depends on SOC_MICROCHIP_POLARFIRE
+ help
+ This driver adds support for the Polarfire SoC mailbox controller.
+
+ To compile this driver as a module, choose M here. the
+ module will be called mailbox-mpfs.
+
+ If unsure, say Y.
+
config QCOM_APCS_IPC
tristate "Qualcomm APCS IPC driver"
depends on ARCH_QCOM || COMPILE_TEST
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 2e06e02b2e03..63f49b5bcc43 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -39,6 +39,8 @@ obj-$(CONFIG_BCM_PDC_MBOX) += bcm-pdc-mailbox.o
obj-$(CONFIG_BCM_FLEXRM_MBOX) += bcm-flexrm-mailbox.o
+obj-$(CONFIG_MPFS_MBOX) += mailbox-mpfs.o
+
obj-$(CONFIG_QCOM_APCS_IPC) += qcom-apcs-ipc-mailbox.o
obj-$(CONFIG_TEGRA_HSP_MBOX) += tegra-hsp.o
diff --git a/drivers/mailbox/mailbox-mpfs.c b/drivers/mailbox/mailbox-mpfs.c
new file mode 100644
index 000000000000..686ccd3317f9
--- /dev/null
+++ b/drivers/mailbox/mailbox-mpfs.c
@@ -0,0 +1,296 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Microchip MPFS system controller/mailbox controller driver
+ *
+ * Copyright (c) 2020 Microchip Corporation. All rights reserved.
+ *
+ * Author: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
+ *
+ */
+
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/mailbox_controller.h>
+#include <soc/microchip/mpfs.h>
+
+#define SERVICES_CR_OFFSET 0x50u
+#define SERVICES_SR_OFFSET 0x54u
+#define MAILBOX_REG_OFFSET 0x800u
+#define MSS_SYS_SUCCESS 0u
+#define MSS_SYS_BUSY 0xefu
+#define MSS_SYS_PARAM_ERR 0xffu
+#define MSS_SYS_MAILBOX_DATA_OFFSET 0u
+
+/***************SCBCTRL SERVICES_CR register*************************/
+
+#define SCBCTRL_SERVICESCR_REQ (0u)
+#define SCBCTRL_SERVICESCR_REQ_MASK BIT(SCBCTRL_SERVICESCR_REQ)
+
+#define SCBCTRL_SERVICESCR_BUSY (1u)
+#define SCBCTRL_SERVICESCR_BUSY_MASK BIT(SCBCTRL_SERVICESCR_BUSY)
+
+#define SCBCTRL_SERVICESCR_ABORT (2u)
+#define SCBCTRL_SERVICESCR_ABORT_MASK BIT(SCBCTRL_SERVICESCR_ABORT)
+
+#define SCBCTRL_SERVICESCR_NOTIFY (3u)
+#define SCBCTRL_SERVICESCR_NOTIFY_MASK BIT(SCBCTRL_SERVICESCR_NOTIFY)
+
+#define SCBCTRL_SERVICESCR_COMMAND (16u)
+#define SCBCTRL_SERVICESCR_COMMAND_MASK (0xffffu << SCBCTRL_SERVICESCR_COMMAND)
+
+/***************SCBCTRL SERVICES_SR registers*************************/
+
+#define SCBCTRL_SERVICESSR_REQ (0u)
+#define SCBCTRL_SERVICESSR_REQ_MASK BIT(SCBCTRL_SERVICESSR_REQ)
+
+#define SCBCTRL_SERVICESSR_BUSY (1u)
+#define SCBCTRL_SERVICESSR_BUSY_MASK BIT(SCBCTRL_SERVICESSR_BUSY)
+
+#define SCBCTRL_SERVICESSR_ABORT (2u)
+#define SCBCTRL_SERVICESSR_ABORT_MASK BIT(SCBCTRL_SERVICESSR_ABORT)
+
+#define SCBCTRL_SERVICESSR_NOTIFY (3u)
+#define SCBCTRL_SERVICESSR_NOTIFY_MASK BIT(SCBCTRL_SERVICESSR_NOTIFY)
+
+#define SCBCTRL_SERVICESSR_STATUS (16u)
+#define SCBCTRL_SERVICESSR_STATUS_MASK (0xffffu << SCBCTRL_SERVICESSR_STATUS)
+
+struct mpfs_mbox {
+ struct mbox_controller controller;
+ struct device *dev;
+ int irq;
+ void __iomem *mailbox_base;
+ void __iomem *int_reg;
+ struct mbox_chan *chan;
+ u16 response_size;
+ u16 response_offset;
+};
+
+static int mpfs_mbox_busy(struct mpfs_mbox *mbox)
+{
+ u32 status;
+
+ status = readl_relaxed(mbox->mailbox_base + SERVICES_SR_OFFSET);
+
+ return status & SCBCTRL_SERVICESSR_BUSY_MASK;
+}
+
+static struct mpfs_mbox *mbox_chan_to_mpfs_mbox(struct mbox_chan *chan)
+{
+ if (!chan || !chan->con_priv)
+ return NULL;
+
+ return (struct mpfs_mbox *)chan->con_priv;
+}
+
+static int mpfs_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+ u32 index;
+ u32 *word_buf;
+ u8 *byte_buf;
+ u8 byte_off;
+ u8 byte_index;
+ u32 mailbox_val = 0u;
+ u16 mb_offset;
+ u16 mbox_options_select;
+ u32 mbox_tx_trigger;
+
+ struct mpfs_mss_msg *msg = data;
+
+ struct mpfs_mbox *mbox = mbox_chan_to_mpfs_mbox(chan);
+
+ mb_offset = msg->mailbox_offset;
+ mbox->response_size = msg->response_size;
+ mbox->response_offset = msg->response_offset;
+
+ mbox_options_select = ((mb_offset << 7u) | (msg->cmd_opcode & 0x7fu));
+ mbox_tx_trigger = (((mbox_options_select << SCBCTRL_SERVICESCR_COMMAND) &
+ SCBCTRL_SERVICESCR_COMMAND_MASK) |
+ SCBCTRL_SERVICESCR_REQ_MASK | SCBCTRL_SERVICESSR_NOTIFY_MASK);
+
+ if (mpfs_mbox_busy(mbox))
+ return MSS_SYS_BUSY;
+
+ /* Code for MSS_SYS_PARAM_ERR is not implemented with this version of driver. */
+
+ writel_relaxed(0x0U, mbox->int_reg);
+
+ if (msg->cmd_data_size > 0u) {
+ byte_buf = (u8 *)(msg->cmd_data);
+
+ for (index = 0u; index < (msg->cmd_data_size / 4u); index++) {
+ writel_relaxed(word_buf[index],
+ mbox->mailbox_base + MAILBOX_REG_OFFSET + index);
+ }
+
+ if ((msg->cmd_data_size % 4u) > 0u) {
+ byte_off = (((msg->cmd_data_size / 4u) * 4u));
+ byte_buf = (u8 *)(msg->cmd_data + byte_off);
+
+ mailbox_val = readl_relaxed(mbox->mailbox_base +
+ MAILBOX_REG_OFFSET + index);
+
+ for (byte_index = 0u;
+ byte_index < (msg->cmd_data_size % 4u);
+ byte_index++) {
+ mailbox_val &= ~(0xffu << (byte_index * 8u));
+ mailbox_val |= (byte_buf[byte_index]
+ << (byte_index * 8u));
+ }
+
+ writel_relaxed(mailbox_val,
+ mbox->mailbox_base + MAILBOX_REG_OFFSET + index);
+ }
+ }
+
+ writel_relaxed(mbox_tx_trigger, mbox->mailbox_base + SERVICES_CR_OFFSET);
+
+ return MSS_SYS_SUCCESS;
+}
+
+static inline int mpfs_mbox_pending(struct mpfs_mbox *mbox)
+{
+ u32 status;
+
+ status = readl_relaxed(mbox->mailbox_base + SERVICES_SR_OFFSET);
+
+ return !(status & SCBCTRL_SERVICESSR_BUSY_MASK);
+}
+
+static void mpfs_mbox_rx_data(struct mbox_chan *chan)
+{
+ struct mpfs_mbox *mbox = mbox_chan_to_mpfs_mbox(chan);
+ u32 *data;
+ u32 index;
+ u32 response_limit;
+
+ data = devm_kzalloc(mbox->dev, sizeof(*data) * mbox->response_size,
+ GFP_ATOMIC);
+
+ response_limit = (mbox->response_size) + (mbox->response_offset);
+ if (mpfs_mbox_pending(mbox) && mbox->response_size > 0U) {
+ for (index = (mbox->response_offset); index < response_limit;
+ index++) {
+ data[index - (mbox->response_offset)] =
+ readl_relaxed(mbox->mailbox_base + MAILBOX_REG_OFFSET +
+ index * 0x4);
+ }
+ }
+
+ mbox_chan_received_data(chan, (void *)data);
+ devm_kfree(mbox->dev, data);
+}
+
+static irqreturn_t mpfs_mbox_inbox_isr(int irq, void *data)
+{
+ struct mbox_chan *chan = (struct mbox_chan *)data;
+ struct mpfs_mbox *mbox = mbox_chan_to_mpfs_mbox(chan);
+
+ writel_relaxed(0x0U, mbox->int_reg);
+
+ mpfs_mbox_rx_data(chan);
+
+ mbox_chan_txdone(chan, 0);
+ return IRQ_HANDLED;
+}
+
+static int mpfs_mbox_startup(struct mbox_chan *chan)
+{
+ struct mpfs_mbox *mbox = mbox_chan_to_mpfs_mbox(chan);
+ int ret = 0;
+
+ if (!mbox)
+ return -EINVAL;
+ ret = devm_request_irq(mbox->dev, mbox->irq, mpfs_mbox_inbox_isr, 0,
+ "mpfs-mailbox", chan);
+ if (unlikely(ret)) {
+ dev_err(mbox->dev, "failed to register mailbox interrupt:%d\n",
+ ret);
+ return ret;
+ }
+
+ return ret;
+}
+
+static void mpfs_mbox_shutdown(struct mbox_chan *chan)
+{
+ struct mpfs_mbox *mbox = mbox_chan_to_mpfs_mbox(chan);
+
+ devm_free_irq(mbox->dev, mbox->irq, chan);
+}
+
+static const struct mbox_chan_ops mpfs_mbox_ops = {
+ .send_data = mpfs_mbox_send_data,
+ .startup = mpfs_mbox_startup,
+ .shutdown = mpfs_mbox_shutdown,
+};
+
+static int mpfs_mbox_probe(struct platform_device *pdev)
+{
+ struct mpfs_mbox *mbox;
+ struct resource *regs;
+ struct mbox_chan *chans;
+ int ret;
+
+ mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), GFP_KERNEL);
+ if (!mbox)
+ return -ENOMEM;
+
+ chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL);
+ if (!chans)
+ return -ENOMEM;
+
+ mbox->mailbox_base = devm_platform_get_and_ioremap_resource(pdev, 0, ®s);
+ if (IS_ERR(mbox->mailbox_base))
+ return PTR_ERR(mbox->mailbox_base);
+
+ mbox->int_reg = devm_platform_get_and_ioremap_resource(pdev, 1, ®s);
+ if (IS_ERR(mbox->int_reg))
+ return PTR_ERR(mbox->int_reg);
+
+ mbox->irq = platform_get_irq(pdev, 0);
+
+ mbox->dev = &pdev->dev;
+
+ chans[0].con_priv = mbox;
+ mbox->controller.dev = mbox->dev;
+ mbox->controller.num_chans = 1;
+ mbox->controller.chans = chans;
+ mbox->controller.ops = &mpfs_mbox_ops;
+ mbox->controller.txdone_irq = true;
+
+ ret = devm_mbox_controller_register(&pdev->dev, &mbox->controller);
+ if (ret) {
+ dev_err(&pdev->dev, "Registering MPFS mailbox controller failed\n");
+ return -1;
+ }
+ dev_info(&pdev->dev, "Registered MPFS mailbox controller driver\n");
+
+ return 0;
+}
+
+static const struct of_device_id mpfs_mbox_of_match[] = {
+ {
+ .compatible = "microchip,polarfire-soc-mailbox",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mpfs_mbox_of_match);
+
+static struct platform_driver mpfs_mbox_driver = {
+ .driver = {
+ .name = "mpfs-mailbox",
+ .of_match_table = mpfs_mbox_of_match,
+ },
+ .probe = mpfs_mbox_probe,
+};
+module_platform_driver(mpfs_mbox_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Conor Dooley <conor.dooley@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("MPFS mailbox controller driver");
--
2.17.1
