From: Peng Fan <peng....@nxp.com>
This patch provides a driver for i.MX Messaging Unit (MU) using the
commom mailbox framework.
This is ported from Linux (v6.12.8) driver
drivers/mailbox/imx-mailbox.c. Its commit SHA is:
39d7d6177f0c ("mailbox: imx: use device name in interrupt name")
Signed-off-by: Viorel Suman <viorel.su...@nxp.com>
Signed-off-by: Peng Fan <peng....@nxp.com>
Signed-off-by: Alice Guo <alice....@nxp.com>
Reviewed-by: Ye Li <ye...@nxp.com>
---
Changes for v1:
- separate this patch from the patch set "add i.MX95 support"
- add support for i.MX7ULP and i.MX8ULP
MAINTAINERS | 1 +
drivers/mailbox/Kconfig | 7 +
drivers/mailbox/Makefile | 1 +
drivers/mailbox/imx-mailbox.c | 456 ++++++++++++++++++++++++++++++++++
4 files changed, 465 insertions(+)
create mode 100644 drivers/mailbox/imx-mailbox.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 687262b355..f13629bc87 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -315,6 +315,7 @@ F: board/freescale/*mx*/
F: board/freescale/common/
F: common/spl/spl_imx_container.c
F: doc/imx/
+F: drivers/mailbox/imx-mailbox.c
F: drivers/serial/serial_mxc.c
F: include/imx_container.h
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
index 67d5ac1a74..4d9f004eba 100644
--- a/drivers/mailbox/Kconfig
+++ b/drivers/mailbox/Kconfig
@@ -21,6 +21,13 @@ config APPLE_MBOX
such as the System Management Controller (SMC) and NVMe and this
driver is required to get that functionality up and running.
+config IMX_MU_MBOX
+ bool "Enable i.MX MU MBOX support"
+ depends on DM_MAILBOX
+ help
+ Enable support for i.MX Messaging Unit for communication with other
+ processors on the SoC using mailbox interface
+
config SANDBOX_MBOX
bool "Enable the sandbox mailbox test driver"
depends on DM_MAILBOX && SANDBOX
diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
index 6072fa1956..574add6000 100644
--- a/drivers/mailbox/Makefile
+++ b/drivers/mailbox/Makefile
@@ -5,6 +5,7 @@
obj-$(CONFIG_$(XPL_)DM_MAILBOX) += mailbox-uclass.o
obj-$(CONFIG_APPLE_MBOX) += apple-mbox.o
+obj-$(CONFIG_IMX_MU_MBOX) += imx-mailbox.o
obj-$(CONFIG_SANDBOX_MBOX) += sandbox-mbox.o
obj-$(CONFIG_SANDBOX_MBOX) += sandbox-mbox-test.o
obj-$(CONFIG_STM32_IPCC) += stm32-ipcc.o
diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c
new file mode 100644
index 0000000000..e774cbb1dc
--- /dev/null
+++ b/drivers/mailbox/imx-mailbox.c
@@ -0,0 +1,456 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2025 NXP
+ */
+
+#include <asm/io.h>
+#include <dm.h>
+#include <dm/device_compat.h>
+#include <mailbox-uclass.h>
+#include <linux/bitfield.h>
+#include <linux/bug.h>
+#include <linux/iopoll.h>
+#include <linux/compat.h>
+
+/* This driver only exposes the status bits to keep with the
+ * polling methodology of u-boot.
+ */
+DECLARE_GLOBAL_DATA_PTR;
+
+#define IMX_MU_CHANS 24
+
+#define IMX_MU_V2_PAR_OFF 0x4
+#define IMX_MU_V2_TR_MASK GENMASK(7, 0)
+#define IMX_MU_V2_RR_MASK GENMASK(15, 8)
+
+enum imx_mu_chan_type {
+ IMX_MU_TYPE_TX = 0, /* Tx */
+ IMX_MU_TYPE_RX = 1, /* Rx */
+ IMX_MU_TYPE_TXDB = 2, /* Tx doorbell */
+ IMX_MU_TYPE_RXDB = 3, /* Rx doorbell */
+ IMX_MU_TYPE_RST = 4, /* Reset */
+ IMX_MU_TYPE_TXDB_V2 = 5, /* Tx doorbell with S/W ACK */
+};
+
+enum imx_mu_xcr {
+ IMX_MU_CR,
+ IMX_MU_GIER,
+ IMX_MU_GCR,
+ IMX_MU_TCR,
+ IMX_MU_RCR,
+ IMX_MU_xCR_MAX,
+};
+
+enum imx_mu_xsr {
+ IMX_MU_SR,
+ IMX_MU_GSR,
+ IMX_MU_TSR,
+ IMX_MU_RSR,
+ IMX_MU_xSR_MAX,
+};
+
+struct imx_mu_con_priv {
+ unsigned int idx;
+ enum imx_mu_chan_type type;
+ struct mbox_chan *chan;
+};
+
+enum imx_mu_type {
+ IMX_MU_V1,
+ IMX_MU_V2 = BIT(1),
+ IMX_MU_V2_S4 = BIT(15),
+ IMX_MU_V2_IRQ = BIT(16),
+};
+
+struct imx_mu {
+ void __iomem *base;
+ const struct imx_mu_dcfg *dcfg;
+ u32 num_tr;
+ u32 num_rr;
+ /* use pointers to channel as a way to reserve channels */
+ struct mbox_chan *channels[IMX_MU_CHANS];
+ struct imx_mu_con_priv con_priv[IMX_MU_CHANS];
+};
+
+struct imx_mu_dcfg {
+ int (*tx)(struct imx_mu *plat, struct imx_mu_con_priv *cp, const void
*data);
+ int (*rx)(struct imx_mu *plat, struct imx_mu_con_priv *cp);
+ int (*rxdb)(struct imx_mu *plat, struct imx_mu_con_priv *cp);
+ int (*init)(struct imx_mu *plat);
+ int (*of_xlate)(struct mbox_chan *chan, struct ofnode_phandle_args
*args);
+ enum imx_mu_type type;
+ u32 xTR; /* Transmit Register0 */
+ u32 xRR; /* Receive Register0 */
+ u32 xSR[IMX_MU_xSR_MAX]; /* Status Registers */
+ u32 xCR[IMX_MU_xCR_MAX]; /* Control Registers */
+};
+
+#define IMX_MU_xSR_GIPn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 -
(x))))
+#define IMX_MU_xSR_RFn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 -
(x))))
+#define IMX_MU_xSR_TEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 -
(x))))
+
+/* General Purpose Interrupt Enable */
+#define IMX_MU_xCR_GIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(28 + (3 -
(x))))
+/* Receive Interrupt Enable */
+#define IMX_MU_xCR_RIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(24 + (3 -
(x))))
+/* Transmit Interrupt Enable */
+#define IMX_MU_xCR_TIEn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(20 + (3 -
(x))))
+/* General Purpose Interrupt Request */
+#define IMX_MU_xCR_GIRn(type, x) (type & IMX_MU_V2 ? BIT(x) : BIT(16 + (3 -
(x))))
+/* MU reset */
+#define IMX_MU_xCR_RST(type) (type & IMX_MU_V2 ? BIT(0) : BIT(5))
+#define IMX_MU_xSR_RST(type) (type & IMX_MU_V2 ? BIT(0) : BIT(7))
+
+static void imx_mu_write(struct imx_mu *plat, u32 val, u32 offs)
+{
+ iowrite32(val, plat->base + offs);
+}
+
+static u32 imx_mu_read(struct imx_mu *plat, u32 offs)
+{
+ return ioread32(plat->base + offs);
+}
+
+static u32 imx_mu_xcr_rmw(struct imx_mu *plat, enum imx_mu_xcr type, u32 set,
u32 clr)
+{
+ u32 val;
+
+ val = imx_mu_read(plat, plat->dcfg->xCR[type]);
+ val &= ~clr;
+ val |= set;
+ imx_mu_write(plat, val, plat->dcfg->xCR[type]);
+
+ return val;
+}
+
+/* check that the channel is open or owned by caller */
+static int imx_mu_check_channel(struct mbox_chan *chan)
+{
+ struct imx_mu *plat = dev_get_plat(chan->dev);
+
+ if (plat->channels[chan->id]) {
+ /* if reserved check that caller owns */
+ if (plat->channels[chan->id] == chan)
+ return 1; /* caller owns the channel */
+
+ return -EACCES;
+ }
+
+ return 0; /* channel empty */
+}
+
+static int imx_mu_chan_request(struct mbox_chan *chan)
+{
+ struct imx_mu *plat = dev_get_plat(chan->dev);
+ struct imx_mu_con_priv *cp;
+ enum imx_mu_chan_type type;
+ int idx;
+
+ type = chan->id / 4;
+ idx = chan->id % 4;
+
+ if (imx_mu_check_channel(chan) < 0) /* check if channel already in use
*/
+ return -EPERM;
+
+ plat->channels[chan->id] = chan;
+ chan->con_priv = kcalloc(1, sizeof(struct imx_mu_con_priv), 0);
+ if (!chan->con_priv)
+ return -ENOMEM;
+ cp = chan->con_priv;
+ cp->idx = idx;
+ cp->type = type;
+ cp->chan = chan;
+
+ switch (type) {
+ case IMX_MU_TYPE_RX:
+ imx_mu_xcr_rmw(plat, IMX_MU_RCR,
IMX_MU_xCR_RIEn(plat->dcfg->type, idx), 0);
+ break;
+ case IMX_MU_TYPE_TXDB_V2:
+ case IMX_MU_TYPE_TXDB:
+ case IMX_MU_TYPE_RXDB:
+ imx_mu_xcr_rmw(plat, IMX_MU_GIER,
IMX_MU_xCR_GIEn(plat->dcfg->type, idx), 0);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int imx_mu_chan_free(struct mbox_chan *chan)
+{
+ struct imx_mu *plat = dev_get_plat(chan->dev);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+
+ if (imx_mu_check_channel(chan) <= 0) /* check that the channel is also
not empty */
+ return -EINVAL;
+
+ /* if you own channel and channel is NOT empty */
+ plat->channels[chan->id] = NULL;
+ switch (cp->type) {
+ case IMX_MU_TYPE_TX:
+ imx_mu_xcr_rmw(plat, IMX_MU_TCR, 0,
IMX_MU_xCR_TIEn(plat->dcfg->type, cp->idx));
+ break;
+ case IMX_MU_TYPE_RX:
+ imx_mu_xcr_rmw(plat, IMX_MU_RCR, 0,
IMX_MU_xCR_RIEn(plat->dcfg->type, cp->idx));
+ break;
+ case IMX_MU_TYPE_TXDB_V2:
+ case IMX_MU_TYPE_TXDB:
+ case IMX_MU_TYPE_RXDB:
+ imx_mu_xcr_rmw(plat, IMX_MU_GIER, 0,
IMX_MU_xCR_GIEn(plat->dcfg->type, cp->idx));
+ break;
+ default:
+ break;
+ }
+
+ kfree(cp);
+
+ return 0;
+}
+
+static int imx_mu_send(struct mbox_chan *chan, const void *data)
+{
+ struct imx_mu *plat = dev_get_plat(chan->dev);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+
+ if (imx_mu_check_channel(chan) < 1) /* return if channel isn't owned */
+ return -EPERM;
+
+ return plat->dcfg->tx(plat, cp, data);
+}
+
+static int imx_mu_recv(struct mbox_chan *chan, void *data)
+{
+ struct imx_mu *plat = dev_get_plat(chan->dev);
+ struct imx_mu_con_priv *cp = chan->con_priv;
+ u32 ctrl, val;
+
+ if (imx_mu_check_channel(chan) < 1) /* return if channel isn't owned */
+ return -EPERM;
+
+ switch (cp->type) {
+ case IMX_MU_TYPE_TXDB_V2:
+ case IMX_MU_TYPE_RXDB:
+ /* check if GSR[GIRn] bit is set */
+ if (readx_poll_timeout(ioread32, plat->base +
plat->dcfg->xSR[IMX_MU_GSR],
+ val, val & BIT(cp->idx), 1000000) < 0)
+ return -EBUSY;
+
+ ctrl = imx_mu_read(plat, plat->dcfg->xCR[IMX_MU_GIER]);
+ val = imx_mu_read(plat, plat->dcfg->xSR[IMX_MU_GSR]);
+ val &= IMX_MU_xSR_GIPn(plat->dcfg->type, cp->idx) &
+ (ctrl & IMX_MU_xCR_GIEn(plat->dcfg->type, cp->idx));
+ break;
+ default:
+ dev_warn(chan->dev, "Unhandled channel type %d\n", cp->type);
+ return -EOPNOTSUPP;
+ };
+
+ if (val == IMX_MU_xSR_GIPn(plat->dcfg->type, cp->idx))
+ plat->dcfg->rxdb(plat, cp);
+
+ return 0;
+}
+
+static int imx_mu_of_to_plat(struct udevice *dev)
+{
+ struct imx_mu *plat = dev_get_plat(dev);
+ fdt_addr_t addr;
+
+ addr = dev_read_addr(dev);
+ if (addr == FDT_ADDR_T_NONE)
+ return -ENODEV;
+
+ plat->base = (struct mu_type *)addr;
+
+ return 0;
+}
+
+static int imx_mu_init_generic(struct imx_mu *plat)
+{
+ unsigned int i;
+ unsigned int val;
+
+ if (plat->num_rr > 4 || plat->num_tr > 4) {
+ WARN_ONCE(true, "%s not support TR/RR larger than 4\n",
__func__);
+ return -EOPNOTSUPP;
+ }
+
+ /* Set default MU configuration */
+ for (i = 0; i < IMX_MU_xCR_MAX; i++)
+ imx_mu_write(plat, 0, plat->dcfg->xCR[i]);
+
+ /* Clear any pending GIP */
+ val = imx_mu_read(plat, plat->dcfg->xSR[IMX_MU_GSR]);
+ imx_mu_write(plat, val, plat->dcfg->xSR[IMX_MU_GSR]);
+
+ /* Clear any pending RSR */
+ for (i = 0; i < plat->num_rr; i++)
+ imx_mu_read(plat, plat->dcfg->xRR + i * 4);
+
+ return 0;
+}
+
+static int imx_mu_generic_of_xlate(struct mbox_chan *chan, struct
ofnode_phandle_args *args)
+{
+ enum imx_mu_chan_type type;
+ int idx, cid;
+
+ if (args->args_count != 2) {
+ dev_err(chan->dev, "Invalid argument count %d\n",
args->args_count);
+ return -EINVAL;
+ }
+
+ type = args->args[0]; /* channel type */
+ idx = args->args[1]; /* index */
+
+ cid = type * 4 + idx;
+ if (cid >= IMX_MU_CHANS) {
+ dev_err(chan->dev, "Not supported channel number: %d. (type:
%d, idx: %d)\n",
+ cid, type, idx);
+ return -EINVAL;
+ }
+
+ chan->id = cid;
+
+ return 0;
+}
+
+static int imx_mu_generic_tx(struct imx_mu *plat, struct imx_mu_con_priv *cp,
+ const void *data)
+{
+ switch (cp->type) {
+ case IMX_MU_TYPE_TXDB_V2:
+ imx_mu_xcr_rmw(plat, IMX_MU_GCR,
IMX_MU_xCR_GIRn(plat->dcfg->type, cp->idx), 0);
+ break;
+ default:
+ dev_warn(cp->chan->dev, "Send data on wrong channel type:
%d\n", cp->type);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int imx_mu_generic_rxdb(struct imx_mu *plat, struct imx_mu_con_priv *cp)
+{
+ imx_mu_write(plat, IMX_MU_xSR_GIPn(plat->dcfg->type, cp->idx),
+ plat->dcfg->xSR[IMX_MU_GSR]);
+
+ return 0;
+}
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
+ .tx = imx_mu_generic_tx,
+ .rxdb = imx_mu_generic_rxdb,
+ .init = imx_mu_init_generic,
+ .of_xlate = imx_mu_generic_of_xlate,
+ .type = IMX_MU_V1,
+ .xTR = 0x0,
+ .xRR = 0x10,
+ .xSR = {0x20, 0x20, 0x20, 0x20},
+ .xCR = {0x24, 0x24, 0x24, 0x24, 0x24},
+};
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
+ .tx = imx_mu_generic_tx,
+ .rxdb = imx_mu_generic_rxdb,
+ .init = imx_mu_init_generic,
+ .of_xlate = imx_mu_generic_of_xlate,
+ .type = IMX_MU_V1,
+ .xTR = 0x20,
+ .xRR = 0x40,
+ .xSR = {0x60, 0x60, 0x60, 0x60},
+ .xCR = {0x64, 0x64, 0x64, 0x64, 0x64},
+};
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx8ulp = {
+ .tx = imx_mu_generic_tx,
+ .rxdb = imx_mu_generic_rxdb,
+ .init = imx_mu_init_generic,
+ .of_xlate = imx_mu_generic_of_xlate,
+ .type = IMX_MU_V2,
+ .xTR = 0x200,
+ .xRR = 0x280,
+ .xSR = {0xC, 0x118, 0x124, 0x12C},
+ .xCR = {0x8, 0x110, 0x114, 0x120, 0x128},
+};
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx95 = {
+ .tx = imx_mu_generic_tx,
+ .rxdb = imx_mu_generic_rxdb,
+ .init = imx_mu_init_generic,
+ .of_xlate = imx_mu_generic_of_xlate,
+ .type = IMX_MU_V2,
+ .xTR = 0x200,
+ .xRR = 0x280,
+ .xSR = {0xC, 0x118, 0x124, 0x12C},
+ .xCR = {0x8, 0x110, 0x114, 0x120, 0x128},
+};
+
+static const struct udevice_id ids[] = {
+ { .compatible = "fsl,imx6sx-mu", .data = (ulong)&imx_mu_cfg_imx6sx },
+ { .compatible = "fsl,imx7ulp-mu", .data = (ulong)&imx_mu_cfg_imx7ulp },
+ { .compatible = "fsl,imx8ulp-mu", .data = (ulong)&imx_mu_cfg_imx8ulp },
+ { .compatible = "fsl,imx95-mu", .data = (ulong)&imx_mu_cfg_imx95 },
+ { }
+};
+
+int imx_mu_of_xlate(struct mbox_chan *chan, struct ofnode_phandle_args *args)
+{
+ struct imx_mu *plat = dev_get_plat(chan->dev);
+
+ return plat->dcfg->of_xlate(chan, args);
+}
+
+struct mbox_ops imx_mu_ops = {
+ .of_xlate = imx_mu_of_xlate,
+ .request = imx_mu_chan_request,
+ .rfree = imx_mu_chan_free,
+ .send = imx_mu_send,
+ .recv = imx_mu_recv,
+};
+
+static void imx_mu_get_tr_rr(struct imx_mu *plat)
+{
+ u32 val;
+
+ if (plat->dcfg->type & IMX_MU_V2) {
+ val = imx_mu_read(plat, IMX_MU_V2_PAR_OFF);
+ plat->num_tr = FIELD_GET(IMX_MU_V2_TR_MASK, val);
+ plat->num_rr = FIELD_GET(IMX_MU_V2_RR_MASK, val);
+ } else {
+ plat->num_tr = 4;
+ plat->num_rr = 4;
+ }
+}
+
+static int imx_mu_probe(struct udevice *dev)
+{
+ struct imx_mu *plat = dev_get_plat(dev);
+ int ret;
+
+ debug("%s(dev=%p)\n", __func__, dev);
+
+ plat->dcfg = (void *)dev_get_driver_data(dev);
+
+ imx_mu_get_tr_rr(plat);
+
+ ret = plat->dcfg->init(plat);
+ if (ret) {
+ dev_err(dev, "Failed to init MU\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+U_BOOT_DRIVER(imx_mu) = {
+ .name = "imx-mu",
+ .id = UCLASS_MAILBOX,
+ .of_match = ids,
+ .of_to_plat = imx_mu_of_to_plat,
+ .plat_auto = sizeof(struct imx_mu),
+ .probe = imx_mu_probe,
+ .ops = &imx_mu_ops,
+ .flags = DM_FLAG_PRE_RELOC,
+};
--
2.43.0
