> -----Original Message----- > From: Oleksij Rempel [mailto:o.rempel@xxxxxxxxxxxxxx] > Sent: Friday, June 15, 2018 5:51 PM > To: Shawn Guo <shawnguo@xxxxxxxxxx>; Fabio Estevam > <fabio.estevam@xxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>; Mark > Rutland <mark.rutland@xxxxxxx>; A.s. Dong <aisheng.dong@xxxxxxx> > Cc: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>; kernel@xxxxxxxxxxxxxx; > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > clk@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx> > Subject: [PATCH v2 4/4] mailbox: Add support for i.MX7D messaging unit > > The Mailbox controller is able to send messages (up to 4 32 bit words) > between the endpoints. > > This driver was tested using the mailbox-test driver sending messages > between the Cortex-A7 and the Cortex-M4. > > Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> > --- > drivers/mailbox/Kconfig | 6 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/imx-mailbox.c | 288 > ++++++++++++++++++++++++++++++++++ > 3 files changed, 296 insertions(+) > create mode 100644 drivers/mailbox/imx-mailbox.c > > diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index > a2bb27446dce..e1d2738a2e4c 100644 > --- a/drivers/mailbox/Kconfig > +++ b/drivers/mailbox/Kconfig > @@ -15,6 +15,12 @@ config ARM_MHU > The controller has 3 mailbox channels, the last of which can be > used in Secure mode only. > > +config IMX_MBOX > + tristate "iMX Mailbox" > + depends on SOC_IMX7D || COMPILE_TEST > + help > + Mailbox implementation for iMX7D Messaging Unit (MU). > + > config PLATFORM_MHU > tristate "Platform MHU Mailbox" > depends on OF > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index > cc23c3a43fcd..ba2fe1b6dd62 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -7,6 +7,8 @@ obj-$(CONFIG_MAILBOX_TEST) += mailbox-test.o > > obj-$(CONFIG_ARM_MHU) += arm_mhu.o > > +obj-$(CONFIG_IMX_MBOX) += imx-mailbox.o > + > obj-$(CONFIG_PLATFORM_MHU) += platform_mhu.o > > obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o > diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c > new file mode 100644 index 000000000000..e3f621cb1d30 > --- /dev/null > +++ b/drivers/mailbox/imx-mailbox.c > @@ -0,0 +1,288 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2018 Pengutronix, Oleksij Rempel > +<o.rempel@xxxxxxxxxxxxxx> */ > + > +#include <linux/clk.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_device.h> > + > +/* Transmit Register */ > +#define IMX_MU_xTRn(x) (0x00 + 4 * (x)) > +/* Receive Register */ > +#define IMX_MU_xRRn(x) (0x10 + 4 * (x)) > +/* Status Register */ > +#define IMX_MU_xSR 0x20 > +#define IMX_MU_xSR_TEn(x) BIT(20 + (x)) > +#define IMX_MU_xSR_RFn(x) BIT(24 + (x)) > +#define IMX_MU_xSR_BRDIP BIT(9) > + > +/* Control Register */ > +#define IMX_MU_xCR 0x24 > +/* Transmit Interrupt Enable */ > +#define IMX_MU_xCR_TIEn(x) BIT(20 + (x)) > +/* Receive Interrupt Enable */ > +#define IMX_MU_xCR_RIEn(x) BIT(24 + (x)) > + > +#define IMX_MU_MAX_CHANS 4u > + > +struct imx_mu_priv; > + > +struct imx_mu_cfg { > + unsigned int chans; > + void (*init_hw)(struct imx_mu_priv *priv); }; > + > +struct imx_mu_con_priv { > + int irq; > + unsigned int bidx; > + unsigned int idx; > +}; > + > +struct imx_mu_priv { > + struct device *dev; > + const struct imx_mu_cfg *dcfg; > + void __iomem *base; > + > + struct mbox_controller mbox; > + struct mbox_chan mbox_chans[IMX_MU_MAX_CHANS]; > + > + struct imx_mu_con_priv con_priv[IMX_MU_MAX_CHANS]; > + struct clk *clk; > +}; > + > +static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox) > +{ > + return container_of(mbox, struct imx_mu_priv, mbox); } > + > +static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs) { > + iowrite32(val, priv->base + offs); > +} > + > +static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs) { > + return ioread32(priv->base + offs); > +} > + > +static u32 imx_mu_rmw(struct imx_mu_priv *priv, u32 offs, u32 set, u32 > +clr) { > + u32 val; > + > + val = imx_mu_read(priv, offs); > + val &= ~clr; > + val |= set; > + imx_mu_write(priv, val, offs); > + > + return val; > +} > + > +static irqreturn_t imx_mu_isr(int irq, void *p) { > + struct mbox_chan *chan = p; > + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); > + struct imx_mu_con_priv *cp = chan->con_priv; > + > + u32 val, dat; > + > + val = imx_mu_read(priv, IMX_MU_xSR); > + val &= IMX_MU_xSR_TEn(cp->bidx) | IMX_MU_xSR_RFn(cp->bidx); > + if (!val) > + return IRQ_NONE; > + > + if (val & IMX_MU_xSR_TEn(cp->bidx)) { I'm wondering whether this can work properly for multi consumers at the same time. Because xSR_TEn is 1 by default and four virtual channels actually are using the same interrupt. That means channel 1 interrupt may cause channel 2 believe it's txdone. Have we tested such using? > + imx_mu_rmw(priv, IMX_MU_xCR, 0, IMX_MU_xCR_TIEn(cp- > >bidx)); > + mbox_chan_txdone(chan, 0); > + } > + > + if (val & IMX_MU_xSR_RFn(cp->bidx)) { > + dat = imx_mu_read(priv, IMX_MU_xRRn(cp->idx)); > + mbox_chan_received_data(chan, (void *)&dat); > + } > + > + return IRQ_HANDLED; > +} > + > +static bool imx_mu_last_tx_done(struct mbox_chan *chan) { > + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); > + struct imx_mu_con_priv *cp = chan->con_priv; > + u32 val; > + > + val = imx_mu_read(priv, IMX_MU_xSR); > + /* test if transmit register is empty */ > + return (!!(val & IMX_MU_xSR_TEn(cp->bidx))); } > + > +static int imx_mu_send_data(struct mbox_chan *chan, void *data) { > + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); > + struct imx_mu_con_priv *cp = chan->con_priv; > + u32 *arg = data; > + > + if (!imx_mu_last_tx_done(chan)) > + return -EBUSY; > + > + imx_mu_write(priv, *arg, IMX_MU_xTRn(cp->idx)); > + imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xSR_TEn(cp->bidx), 0); > + > + return 0; > +} Since Sascha is requesting to write a generic MU mailbox driver for both SCU MU and M4 case, the current way using virtual channels in this patch only send one word a time obviously can't fit for SCU MU clients well. Do you think if we can refer to TI case to design a generic data transfer protocol to allow send multi words which is more close to SCU? include/linux/soc/ti/ti-msgmgr.h struct ti_msgmgr_message { size_t len; u8 *buf; }; Or we try to support both type transfer protocols in this driver? That may introduce much complexities, personally I'm not quite like that. Regards Dong Aisheng > + > +static int imx_mu_startup(struct mbox_chan *chan) { > + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); > + struct imx_mu_con_priv *cp = chan->con_priv; > + int ret; > + > + ret = request_irq(cp->irq, imx_mu_isr, > + IRQF_SHARED, "imx_mu_chan", chan); > + if (ret) { > + dev_err(chan->mbox->dev, > + "Unable to acquire IRQ %d\n", cp->irq); > + return ret; > + } > + > + imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xCR_RIEn(cp->bidx), 0); > + > + return 0; > +} > + > +static void imx_mu_shutdown(struct mbox_chan *chan) { > + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); > + struct imx_mu_con_priv *cp = chan->con_priv; > + > + imx_mu_rmw(priv, IMX_MU_xCR, 0, > + IMX_MU_xCR_TIEn(cp->bidx) | IMX_MU_xCR_RIEn(cp- > >bidx)); > + > + free_irq(cp->irq, chan); > +} > + > +static const struct mbox_chan_ops imx_mu_ops = { > + .send_data = imx_mu_send_data, > + .startup = imx_mu_startup, > + .shutdown = imx_mu_shutdown, > +}; > + > +static int imx_mu_probe(struct platform_device *pdev) { > + struct device *dev = &pdev->dev; > + struct resource *iomem; > + struct imx_mu_priv *priv; > + const struct imx_mu_cfg *dcfg; > + unsigned int i, chans; > + int irq, ret; > + > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + dcfg = of_device_get_match_data(dev); > + if (!dcfg) > + return -EINVAL; > + > + priv->dcfg = dcfg; > + priv->dev = dev; > + > + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + priv->base = devm_ioremap_resource(&pdev->dev, iomem); > + if (IS_ERR(priv->base)) > + return PTR_ERR(priv->base); > + > + irq = platform_get_irq(pdev, 0); > + if (irq <= 0) > + return irq < 0 ? irq : -EINVAL; > + > + priv->clk = devm_clk_get(dev, NULL); > + if (IS_ERR(priv->clk)) { > + if (PTR_ERR(priv->clk) == -ENOENT) { > + priv->clk = NULL; > + } else { > + dev_err(dev, "Failed to get clock\n"); > + return PTR_ERR(priv->clk); > + } > + } > + > + ret = clk_prepare_enable(priv->clk); > + if (ret) { > + dev_err(dev, "Failed to enable clock\n"); > + return ret; > + } > + > + chans = min(dcfg->chans, IMX_MU_MAX_CHANS); > + /* Initialize channel identifiers */ > + for (i = 0; i < chans; i++) { > + struct imx_mu_con_priv *cp = &priv->con_priv[i]; > + > + cp->bidx = 3 - i; > + cp->idx = i; > + cp->irq = irq; > + priv->mbox_chans[i].con_priv = cp; > + } > + > + priv->mbox.dev = dev; > + priv->mbox.ops = &imx_mu_ops; > + priv->mbox.chans = priv->mbox_chans; > + priv->mbox.num_chans = chans; > + priv->mbox.txdone_irq = true; > + > + platform_set_drvdata(pdev, priv); > + > + if (priv->dcfg->init_hw) > + priv->dcfg->init_hw(priv); > + > + return mbox_controller_register(&priv->mbox); > +} > + > +static int imx_mu_remove(struct platform_device *pdev) { > + struct imx_mu_priv *priv = platform_get_drvdata(pdev); > + > + mbox_controller_unregister(&priv->mbox); > + clk_disable_unprepare(priv->clk); > + > + return 0; > +} > + > + > +static void imx_mu_init_imx7d_a(struct imx_mu_priv *priv) { > + /* Set default config */ > + imx_mu_write(priv, 0, IMX_MU_xCR); > +} > + > +static const struct imx_mu_cfg imx_mu_cfg_imx7d_a = { > + .chans = IMX_MU_MAX_CHANS, > + .init_hw = imx_mu_init_imx7d_a, > +}; > + > +static const struct imx_mu_cfg imx_mu_cfg_imx7d_b = { > + .chans = IMX_MU_MAX_CHANS, > +}; > + > +static const struct of_device_id imx_mu_dt_ids[] = { > + { .compatible = "fsl,imx7s-mu-a", .data = &imx_mu_cfg_imx7d_a }, > + { .compatible = "fsl,imx7s-mu-b", .data = &imx_mu_cfg_imx7d_b }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, imx_mu_dt_ids); > + > +static struct platform_driver imx_mu_driver = { > + .probe = imx_mu_probe, > + .remove = imx_mu_remove, > + .driver = { > + .name = "imx_mu", > + .of_match_table = imx_mu_dt_ids, > + }, > +}; > +module_platform_driver(imx_mu_driver); > + > +MODULE_AUTHOR("Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Message Unit driver for i.MX"); > MODULE_LICENSE("GPL > +v2"); > -- > 2.17.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
